Environment & Energy
Related: About this forumIntermittency Of Renewables?… Not So Much
http://cleantechnica.com/2013/07/21/intermittency-of-renewable-energy/Below was a great summary (if a bit simplified in parts) comment from one of our readers on one of our posts last week. I thought it deserved a few more eyes. Also, I happened to go back to a roundtable discussion of utility CEOs today that supports the overall “the ‘intermittency’ of renewable energy issue is overhyped” argument. More on that below the reader comment.
<snip>
First, the then CEO and President of Florida Power & Light, Armando Olivera, chimed in. “I spent a lot of time in operations in our company. Of all the things that I worry about, regulating using solar, or renewables, really doesn’t worry me. I think you gotta be at a really huge scale of solar before that becomes an issue. And in the meantime, we’ve got a lot of enabling technology going into these grids… about half of the meters at FPL are already automated devices. We are learning a huge… we’re seeing benefits that we didn’t fully anticipate in terms of managing the grid. We’re also putting in a lot of smart technology that can adjust at a very local level whenever there’s a problem. So, you know, I think there’s a huge foundation that’s being laid out today that will facilitate all of these technologies….”
Doyle Beneby, President & CEO of CPS Energy, backed him up. ”Yeah, I would agree with Armando, I don’t worry about that at all…. Generally, if you’ve got automated meters, if you’ve got the means for a home area network, I think you can easily reduce demand to follow — I call it load-following — for solar. What we found, also, is that there are a very discreet set of customers out there who would volunteer to have their load reduced to follow the drop in output for solar…. So I think that’s a big opportunity out (there) for us. I really think concerns about the grid, so to speak, and even to a degree intermittency, should not at all impede the progress of solar.”
Robert Powers, President of AEP Utilities, also chimed in and said, “I agree with my colleague that near-term there’s no, no issue with grid stability with deploying solar.”
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cprise
(8,445 posts)Sustainability isn't all about waiting for technology to give us drop-in replacements for fossil fuels. There are people who recognize the need to change our daily routines to reduce our impact on the environment; there should be more effort put into enabling them.
BlueStreak
(8,377 posts)I don't see why anybody would have to be discreet about being on the leading edge of using solar power wisely.
PamW
(1,825 posts)jpak,
Once again, jpak; you demonstrate that you don't understand the issue of intermittency with regard to non-dispatchable renewables.
As long as the non-dispatchable renewables are a small portion of the generators on the grid; less than 20; there is no problem with the intermittency of the renewables.
If non-dispatchable renewables are <20% of the generating capacity; then the dispachable generators are >80% of the generation capacity.
Unlike non-dispatchable renewables; the dispatchable generators have a feedback mechanism controlling the generator's "throttle", and hence are designed to compensate for variations in the demand/load. The variation of due to the intermittency of the non-dispatchable renewables looks like a fluctuation in the demand/load which the dispatchable generators are designed to compensate for.
As with most electric systems, the percentage of non-dispatchable renewables in the FPL system is small. Therefore, the dispatchable generators in the FPL system can compensate for the variability of the non-dispatchable renewables and Mr. Olivera presently doesn't have a problem, and states so.
Evidently, jpak doesn't understand that the problem does NOT surface now when non-dispatchable renewables are such a meager portion of the energy supply mix. The problem is one to be faced in the FUTURE when non-dispatchable renewables are a larger component of the energy generation mix.
Both energy CEOs ALLUDE to this FUTURE problem:
"I think you gotta be at a really huge scale of solar before that becomes an issue."
-- Armando Olivera
“I agree with my colleague that near-term there’s no, no issue with grid stability with deploying solar.”
-- Robert Powers
Both CEOs are saying that near-term, when non-dispatchable renewables are a meager component of the energy generation system; there is no problem because the dispatchable generators can compensate for the non-dispatchable renewables, as they ( the dispatchables ) are designed to do.
The problem with the variation in the output of non-dispatchable renewables comes in the FUTURE if we follow the lame suggestions to go "100% non-dispatchable renewable", as some here advocate.
THEN you don't have the dispatchable generators, coal, gas, hydro, and nuclear; to rely on for correcting the spurious variations in the output of non-dispatchable renewables.
Mischaracterizing the problem by stating that there is no problem when non-dispatchable renewables are a small component of the generating capacity, and thereby ERRONEOUSLY concluding that non-dispatchable renewable variability won't be a problem when non-dispatchable renewables are a higher percentage of the energy mix; is NOT HELPFUL for the forum readers, and FALSELY trivializes a future obstacle to the use of non-dispatchable renewables as a high percentage of our energy supply.
PamW
kristopher
(29,798 posts)There is some information compiled here to assist readers in putting PamGreg's ravings into a broader context:
http://www.democraticunderground.com/?com=view_post&forum=1127&pid=48646
PamW
(1,825 posts)Last edited Mon Jul 29, 2013, 10:16 AM - Edit history (1)
Once again kristopher is spreading his oft repeated LIE that I am one and the same as another member that was banned from this forum; and he offers the following as "evidence":
http://www.democraticunderground.com/?com=view_post&forum=1127&pid=48646
I have perused this LAME so-called "evidence" and find it to be more of a litany of the scientific ERRORS and MISUNDERSTANDINGS of kristoper.
For example, let's take the following post from the discussion of electric cars vs. internal combustion engines, which contains a quote from kristopher followed by a rebuttal from Dr. Gregory:
http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=115x258338#258993
in which kristopher makes the following statement:
For example, did you know that for our personal transportation fleet, about 80% of the energy in the petroleum fuel doesn't even need to be replaced as it is simply wasted as heat and serves no functional purpose?
ERROR!!! ERROR!! ERROR!!!
The statement above unambiguously shows that kristopher does NOT UNDERSTAND the 2nd Law of Thermodynamics. Waste heat DOES SERVE an important purpose. If kristopher had bothered to attempt to educate himself by following the link that Dr. Gregory provided, he would see, courtesy of the Physics Department at Georgia State University:
http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/seclaw.html#c2
Second Law of Thermodynamics: It is impossible to extract an amount of heat QH from a hot reservoir and use it all to do work W . Some amount of heat QC must be exhausted to a cold reservoir. This precludes a perfect heat engine.
The heat "QC" is the "waste heat", and the 2nd Law of Thermodynamics says ( as quoted above ) "MUST be exhausted to cold reservoir"
Contrary to kristopher's ill-considered statement, "waste heat" serves a very NECESSARY purpose. (Waste heat serves as the necessary sink for entropy; more on that later)
Evidently, kristopher wants heat engines with no waste heat ( because he doesn't want to replace that portion ), and therefore is proposing a thermodynamic cycle as depicted in the right half of the diagram. That's a thermodynamic cycle in which heat energy "QH" is 100% converted into work "W", which would constitute a "perfect heat engine".
However the Georgia State University Physics Department website states the following about this cycle:
Extracting heat QH and using it all to do work W would constitute a perfect heat engine FORBIDDEN by the second law.
Evidently, kristopher can't fathom the "why" and "how" of the 2nd Law of Thermodynamics.
However, there do exist people with the high intellect and prodigious mental horsepower that CAN fathom the "why" and "how" of the 2nd Law of Thermodynamics. Those people are the Physicists, like those on staff at the national laboratories ( me ), and the Professors of Physics at Universities around the world, and, in particular; at the Physics Department of Georgia State University.
Those physicists say that the "perfect heat engine" envisioned by kristopher is FORBIDDEN by the 2nd Law.
One may not be able to comprehend the "why"; but one should surely be able to understand the implications of the 2nd Law of Thermodynamics when pointed out by University Professors, or their website; which states that the "perfect heat engine" with no waste heat is FORBIDDEN by the 2nd Law of Thermodynamics.
I understand that this doesn't sit well with so-called "progressives", who are always attempting to attain 100% efficiency and eliminate any type of waste. Unfortunately, Mother Nature is NOT a "progressive". She doesn't maintain the same value system that "progressives" do.
Contrary to the wishes and "sensibilities" of "progressives"; the 2nd Law of Thermodynamics imposes an upper limit on the efficiency that can be attained with a heat engine; which is called the "Carnot Efficiency".
In my experience, when confronted with this this scientific truth, the progressives protest, "But I know of heat engines that are rated at 98% efficiency; so how can the 2nd Law of Thermodynamics impose an efficiency limit?"
Here again, the "progressive" is misled by their lack of understanding. When an efficiency of 98% is quoted for a heat engine; that is an isentropic efficiency.
http://en.wikipedia.org/wiki/Steam_turbine
Suppose for the temperature conditions, the Carnot Efficiency was 70%. Scientists and engineers realize that they can not attain heat engine efficiencies that are higher than the Carnot Efficiency. However, they would like a metric as to how close they are to the theoretical maximum. So the "isentropic efficiency" is the actual efficiency divided by the theoretical maximum which is the Carnot Efficiency.
In this case an efficiency that equals the theoretical maximum, would be an isentropic efficiency of 100% In the above case, the heat engine that has an isentropic efficiency of 98% when the Carnot Efficiency is 70%; has an actual efficiency of 68.6% so that it doesn't violate the theoretical maximum.
Still, I often hear the "progressives" make the flawed comparison; "This heat engine has an efficiency of 98%; which is greater than the Carnot Efficiency of 70%; so you are wrong about the Carnot Efficiency being the maximum attainable" ( Everyone see the FLAWED "logic" in the above statement? )
If the 2nd Law of Thermodynamics says that "waste heat" has a purpose; then what is it? In a nutshell; the purpose of the waste heat is to "conserve" entropy. The 1st Law of Thermodynamics is Conservation of Energy tells us that QH = QC + W. That is the energy from the hot reservoir equals the sum of the "waste heat", QC, and the useful work, W.
That isn't enough to uniquely specify the cycle. There's another quantity that must be reckoned with; the entropy. The 2nd Law of Thermodynamics tells us that the entropy is either conserved, or it may increase. The heat engine is most efficient if the entropy is conserved, as opposed to being increased.
Suppose we look at the flow of entropy in kristopher's ill-conceived perfect heat engine with no waste heat. There is entropy associated with the hot reservoir energy QH. There is ZERO entropy associated with the useful work W. If the only thing that happens is that QH is converted to work W; then entropy has been destroyed! That is in strict VIOLATION of the 2nd Law of Thermodynamics; which is why we can NEVER have a heat engine that does what kristopher wants; which is to have no waste heat.
The purpose of the waste heat is to carry off entropy.
In the best possible, most efficient heat engine; the entropy carried off by the waste heat exactly equals the input entropy.
That is why kristopher's statement that waste heat serves no functional purpose is JUST PLAIN 100% WRONG.
That statement merely serves to highlight kristopher's LACK of UNDERSTANDING of the Laws of Physics. Dr. Gregory was COMPLETELY CORRECT on that one.
Or let's take the question of thermal pollution from a solar power plant. The fact that there IS thermal pollution from solar power plants is well known among scientists; but not the general public, as well as many of the denizens of this forum. From an examination of the thread referenced by kristopher, it appears that he and his supporters do not know about the Stefan-Bolzmann Law, and thermal radiation. They believe objects just absorb; and don't radiate. Anyone who has ever seen the view from a FLIR or nightscope has seen the radiant energy from humans. Well, ALL objects radiate depending on their temperature; even those that are not as hot as human bodies. They just radiate at lower frequencies.
So an object placed in the sunlight will not just keep absorbing energy and rising in temperature. An object will reach equilibrium temperature when the rate of energy influx from the sun equals the rate of energy outflux due to both reflection and reradiation:
Solar influx rate = Reflection outflux rate + Reradiation outflux rate
S = (alpha_e) S + b (T_e)^4
where S is the solar energy influx rate, (alpha_e) is the albedo of the environment, and "b" is a factor that includes the Stephan-Boltzmann constant, the surface area,...but the actual value isn't germane to the argument, just the fact that b is positive; b > 0.
Now suppose we put solar cells down over our environment. There are two modifications to the above equation. The albedo changes to (alpha_c), the albedo of a solar collector. Solar collectors are made to be DARK so that they don't reflect the sun's energy. So (alpha_c) < (alpha_e). The other is that there is another way that energy is removed from the system, and that is in the form of electricity. The generation rate will be equal to the product of the efficiency (e_c) of the solar collector and the non-reflected solar influx ( 1 - alpha_c ) S. So for the solar collector, the balance equation for equilibrium is:
S = (alpha_c) S + (e_c)(1 - alpha_c)S + b (T_c)^4
Since both right hand sides equal the solar influx rate, we can set them equal to each other and solve for the difference in reradiation rates which is proportional to the difference in the fourth-powers of the temperatures. Thus we can determine the sign ( + or - ) of the difference between the temperature without the collectors (T_e) and the temperature with the solar collectors (T_c):
b ( (T_c)^4 - (T_e)^4 ) = ( alpha_e - alpha_c - (e_c)( 1 - alpha_c ) ) S
We know that alpha_e > alpha_c; and the efficiency of solar collectors is rather small. So the right hand side of the above equation is positive; which means that T_c > T_e or that the environmental temperature will be HOTTER in the case WITH the solar collectors.
If the reader has a hard time following that; consider the following courtesy of North Carolina State University:
http://www.nc-climate.ncsu.edu/edu/k12/.albedo
OK, progressives; put your "thinking caps" on and follow along. Note the example of putting a black tarp over plants to help keep them warm. The low albedo of the black tarp minimizes the amount of energy reflected away, so it can be used to keep the plants warm. The albedo of a solar collector is also low, because we don't want to reflect energy away; we want to capture it so we have a chance of changing it into electricity. So like the case with the plants, we are capturing MORE energy with either the black tarp or solar collector in place than would be the case if we didn't have either.
Now, if solar collectors were 100% efficient, we would turn all that extra captured solar energy into electricity and send it somewhere else, so it can't thermally pollute our solar collector site. However, solar cells are NOT 100% efficient; they are 20% to 30% efficient. Therefore, 70% - 80% of that extra captured energy is NOT sent offsite, it shows up as waste heat from the solar collector; and is the source of thermal pollution from the solar collector.
Q.E.D. - Dr. Gregory was CORRECT -- AGAIN.
An objective, intelligent examination of the threads cited by kristopher, conclusively shows that Dr. Gregory has the SUPERIOR intellect, the SUPERIOR powers of reason, and the SUPERIOR scientific knowledge.
Now to kristopher's "logic" that concludes that Dr. Gregory and I are one and the same. Evidently, kristoper "thinks" that the principles espoused by Dr. Gregory in the cited posts, and my current posts are just a bunch of right-wing fabrications to denigrate non-dispatchable renewables. Evidently, kristopher believes that only a single person could concoct this particular mix of "right-wing fabrications". Since Dr. Gregory and I both espouse this particular mix of "right-wing fabrications"; then Dr. Gregory and I must be the same person.
The CONCLUSIVELY DEMONSTRATED FLAW in kristopher's "logic" is that these are NOT "right-wing fabrications" to denigrate non-dispatchable renewables. They are, in truth; SCIENTIFIC FACTS.
The reason Dr. Gregory and I sound so similar to kristopher is NOT because we are the same person; but rather, Dr. Gregory and I are evidently BOTH SCIENTISTS. Two SCIENTISTS are going to sound similar because they are both giving you the SCIENTIFIC TRUTH.
What is distressing is that evidently this forum BANNED a scientist merely for speaking the SCIENTIFIC TRUTH.
Now kristopher is calling for me to be banned:
http://www.democraticunderground.com/112748437#post18
"You need to be out of here."
That's not the hallmark of an enlightened group that values diversity!! That's CENSORSHIP.
Kristopher calls it "editorial control".
Is that what the denizens of this forum want; an "editorial control" that sanctions only a pablum of falsehoods; pseudo-science masquerading as real science, and "seasoned" to fit the tastes of progressives; and all that real science is to be DAMNED and BANNED just because you don't "like" it?
Do you know what that sounds like? That sounds like the tactics of CLIMATE DENIERS. They don't like real science either, because it says that they are polluting and/or making money off of polluting. They can't acknowledge that. So they disown and deny the science. Don't we call the climate deniers STUPID and DISHONEST because they don't want what scientists tell them to be in their midst?
So what words do we use for the "flip side" of the coin; people that also want scientists banned; the only difference being a different political agenda. Does having the "correct" political agenda give you a "pass" to engage in anti-scientific censorship?
PamW
Quite the spirited defense of a TS'ed ex-DUer. 
kristopher
(29,798 posts)Also repeats to a T the same red herrings and strawmen he originally used.
jpak
(41,755 posts)Germany and Portugal and Denmark and Iowa and Spain generate 20-50% of their power from non-dispatchable renewable sources all the fucking time.
Lyndon LaRouche still sucks...
ass.
YUP
kristopher
(29,798 posts)The National Academy of Sciences concluded that we'll need to enact policies that favor renewable integration to enable a penetration into the 50% range, and that above that, we'd need to restructure the nature of the grid so that it is centered around the generating characteristics of renewables instead of centralized generator. In sum these changes mean a computerized "smart grid" that can watch power flow down to the single kilowatt level and the bolstering of technologies that can ramp up and down quickly - specially designed turbine generators (that can run off of either natural gas or biomethane) and various forms of storage fit this need.
See also:
Cost-minimized combinations of wind power, solar power and electrochemical storage, powering the grid up to 99.9% of the time
Open Access Article
Abstract
We model many combinations of renewable electricity sources (inland wind, offshore wind, and photovoltaics) with electrochemical storage (batteries and fuel cells), incorporated into a large grid system (72 GW).
The purpose is twofold:
1) although a single renewable generator at one site produces intermittent power, we seek combinations of diverse renewables at diverse sites, with storage, that are not intermittent and satisfy need a given fraction of hours. And
2) we seek minimal cost, calculating true cost of electricity without subsidies and with inclusion of external costs.
Our model evaluated over 28 billion combinations of renewables and storage, each tested over 35,040 h (four years) of load and weather data.
We find that the least cost solutions yield seemingly-excessive generation capacity — at times, almost three times the electricity needed to meet electrical load. This is because diverse renewable generation and the excess capacity together meet electric load with less storage, lowering total system cost.
At 2030 technology costs and with excess electricity displacing natural gas, we find that the electric system can be powered 90%–99.9% of hours entirely on renewable electricity, at costs comparable to today's—but only if we optimize the mix of generation and storage technologies.
Full article available http://www.sciencedirect.com/science/article/pii/S0378775312014759
PamW
(1,825 posts)Above, kristopher state:
In sum these changes mean a computerized "smart grid" that can watch power flow down to the single kilowatt level
As per always, kristopher is just "blowing smoke", in his statement above. First, kristopher identifies the need to watch power flow "down to the single kilowatt level", in essence hypothesizing an potential error of a single kilowatt.
BZZZZT!! WRONG!! ERROR!!! ERROR!!!
If the error in your measurement is 1 kilowatt, then that means the system would allow a mismatch of generation to load and loss of a killowatt. In a single second, that would mean the system would either create or destroy 1000 Joules of energy - depending on whether generation lagged or exceeded demand/loss.
Do you honestly "think" that Mother Nature will let you get away with either creating or destroying 1000 Joules?
The Law of Conservation of Energy does NOT allow a mismatch as large as 1000 Joules.
There are two failings that non-dispatchable renewables have relative to their dispatchable counterparts. One failing is the inability to sense load. Dispatchable generators like coal, gas, hydro, and nuclear; have generators that are "synched" to the power line, and hence can "sense" the load via Lenz's Law. ( Go look up Lenz's Law in any physics textbook ). If you want to pick up a bucket of rocks, you don't need an "app" on your iPhone that tells you how much the rocks weigh, and hence how much force you need to supply. You can "feel" the weight of the rocks when you pick them up; and provide the necessary level of force.
Non-dispatchable renewables like solar and wind do NOT have generators that are "syched" to the power line, and hence can't "feel" the load via Lenz's Law. That is not a fatal flaw; that issue can be addressed. That is what a "smart grid" is all about. The "smart grid" receives the electric energy demand from each of the loads on the grid and sums up those loads/demands to report to the generators on the grid. The "smart grid" is analogous to the iPhone app that tells you how much the rocks weigh above.
The other, more serious, failing of non-dispatchable renewables is the lack of a "throttle". If your "smart grid" or whatever reports the load that a given generator has to supply; how does one adjust the energy produced to match the demand.
Again, dispatchable generators have a feedback system that senses the load / demand via Lenz's Law; the added demand results in a great "back-torque" in the generator, and the plant has a feedback system to provide more power to the generator to compensate. The feedback system opens the throttle valve on the turbines, and in case of coal or gas, also regulates the fuel flow valve; and in the case of a reactor, inherent temperature feedbacks, principally the moderator/coolant temperature feedback adjusts reactor power.
Non-dispatchable renewables like wind and solar do NOT have throttles; which is why they are "non-dispatchable" by definition. How does one demand more energy from Mother Nature than what she is offering at the time?
When the renewables "engineers" accomplish their deluded attempt to make demands on Mother Nature; let me know.
PamW
kristopher
(29,798 posts)The present grid isn't "designed" to pay attention to generating sources smaller than the 1MW level.
There is some information compiled at the link below to assist readers in putting PamGreg's ravings into a broader context.
http://www.democraticunderground.com/?com=view_post&forum=1127&pid=48646
For example, did you know that, according to the physics of Pam/DrGreg the Earth reflects 90% of the Sun's energy? This is the post making the claim, those that follow (its the first sample at the page link above) explain the problem with the statement. It shows that Pam/DrGreg simply has no sense of shame when it comes claims that are demonstrated to be false.
not without energy storage. For half the 24 hour day the
solar plant doesn't see the sun - so produces ZERO.
2 Gigawatts is a BIG scale up. The largest solar plants built
to date are 2 Megawatts ( 1000X smaller ) and Spain is currently
building a 20 Megawatt plant ( 100X smaller )
Solar is less efficient than Rankine steam cycles. Also the
argument that the solar proponents give that the sunlight falls
there anyway is false.
A typical landscape REFLECTS about 90% of the suns energy. Only
10% is absorbed. A PV plant will absorb 100% of the energy if it
is efficient < black in color >, and will convert about 20% to
electricity and discharge 80% as heat.
So if we take a piece of land with 100 watts of sunlight falling
on it; then if we leave it alone - we will have 10 watts of solar
heating.
If we build a PV plant; then that same area will give us 20 watts,
and we will have 80 watts of heating.
If we built a Rankine steam cycle plant, of 40% efficiency; or
1.5 times as much waste heat as electricity; then for the same
20 watts, we would have 30 watts of waste heat, plus the 10 watts
from the sun or 40 watts of heat total.
That 40 watts is HALF of what a PV plant would discharge.
PamW
(1,825 posts)kristopher states:
The present grid isn't "designed" to pay attention to generating sources smaller than the 1MW level.
Kristopher has ABSOLUTELY NO IDEA of what I'm talking about.
I am talking about the generator speed controller that EVERY dispatchable power plant that has a rotating generator synched to the grid has.
Those speed controllers are VERY PRECISE, and in addition, the extremely high degree of power matching is guaranteed by the fact that the controller is in a feedback loop.
I see that once again, I have to spoon-feed the scientific truth to kristopher in small bites.
Suppose the system is starts in equilibrium; that is power of the generators equals the instantaneous demand including line losses.
Now suppose a large factory starts up and starts drawing current. The fact that the factory starts drawing current means that there is an increase in the current of the generator's armature coils. Because of Lenz's Law, a basic Law of Physics / Electrodynamics; the increased current flow in the armature coils creates an increase in the torque required to keep the generator spinning at its current speed. The turbine is not putting out this new higher torque; it's putting out the previous torque when the grid didn't have the factory drawing energy.
That mismatch in torque would cause the generator to slow down; because the system is drawing kinetic energy from the generator in order to supply the energy the factory is drawing. Energy has to be conserved at all times. However, if this were to persist, the generator would get out of sync with the grid. Therefore, a very precise frequency measuring circuit detects the very slight slowing of the generator, and further opens the throttle valve on the turbine driving the generator. In the case of a hydro plant, that is all that is required. If the plant is coal or gas-fired, or nuclear; the feedback circuit also increases fuel flow in the coal or gas plant, and inherent temperature feedback due to the moderator / coolant reactivity temperature coefficient, serves to increase reactor power in a nuclear plant.
With both the prime mover and the turbine throttled up; the system is again in equilibrium, and if not - it adjusts until it IS in equilibrium.
What kristopher speaks about ignoring levels below 1 Mw is the software used by the load dispatchers. The load dispatchers only have to do a COARSE tuning of the grid, hence they can safely ignore small generator sources.
However, once the load dispatchers have done a COARSE tune of the grid; the speed controllers and their feedback circuits do the NECESSARY fine tuning automatically.
Admit it kristopher; until you read the above, you had ABSOLUTELY NO IDEA of the existence of the speed controllers, their feedback circuits, and how that functions to PRECISELY match generator supply and demand.
Where is it, again, that you studied electric power engineering, Kristopher?
I thought NOT!
PamW
kristopher
(29,798 posts)What you describe is one element in the design of the present grid. But PamGreg, there are others that are equally, if not more, important - such as the basic act of load balancing performed by the grid operators.
But going from the existence of that aspect of the present centralized grid, to the statement that we cannot achieve large scale renewable integration or build a 100% renewable grid (which is your entire point) is stark raving lunacy.
We balance load at many points in the system and in a fully renewable grid all of the present points will still be there, including "LENZ'S LAW" (quoting your shout).
We will still have thermal power generation, we will still have turbines (only they will be geothermal, hydro, biomass and biomethane) throttling up and down, but we will also be "COARSE tuning" down to the kilowatt level. And that is something we can't do with presently installed 'dumb' technology - the change is what the smart grid is all about.
We will have vastly more battery storage (instant reactive power) - especially in the electric vehicle fleet (V2G). There will be more end use applications that are designed to work on stored heat in order to take advantage of spilled wind and solar - in other words the smart grid will be able to selectively turn on demand in order to help balance load.
All of these and more (eg inverters) are elements of making a renewable grid work and each of them has a solid foundation in physics along with names for the properties they embody. Your focus on the obscure name of a single aspect as the be-all-end-all of everything is a true testament to your dedication to disrupting legitimate discussion on this forum.
PamW
(1,825 posts)kris,
The fact that you DO NOT UNDERSTAND the first 8 paragraphs doesn't mean it's BS.
Quit attempting to be a faux scientist.
You make claims about Lenz's Law; and you have ABSOLUTELY NO CLUE as to when / how it works. Lenz's Law operates with rotating generators that are synced to the line. That, the speed control feedback, and the prime mover throttles means that the plant is dispatchable and can regulate its power as the line demand.
I'm familiar with and have studied all the proposals for the "smart grid", and it doesn't offer anything that can't be done presently. It's merely a substitute for the information that present day generators can get from the power line itself. The load dispatchers in conjunction with power plant operators can throttle dispatchable plants at any level. Then the automatic controllers do the fine tuning based on the specifics of the demand.
Kris, don't use scientific terms that you don't understand; like referring to batteries as supplying "reactive power".
"Reactive power" is a specific term that applies ONLY to AC power lines, and NOT the DC lines of a battery:
http://en.wikipedia.org/wiki/Volt-ampere_reactive
Reactive power exists in an AC circuit when the current and voltage are not in phase.
So NO; the DC current from batteries is NOT "instant reactive power"; so STOP LYING.
As far as the mix of power from turbines that you postulate; have you any figures as to HOW MUCH the resource is for those options? For example, geothermal; how much geothermal power do you think we can harness; and why hasn't it been developed to that level?
Boy you really have zero acumen with science. You are so glib to dismiss something that plan glosses over, and then you criticize me for harping on it. Science doesn't work like that. What you "think" is some trivial concept that you can gloss over; is a MAJOR VIOLATION of the Laws of Physics; which means that Mother Nature will NOT LET YOUR PLAN WORK.
It's akin to saying the tail of an airplane; vertical and horizontal stabilizers; are just trivial things that some aerodynamic engineer keeps harping on for no apparent reason. But try flying without them.
Why all this BACK-PEDALING?? What has become of all your claims of 100% wind / solar grids.
PamW
kristopher
(29,798 posts)No one else. It is one of your favorite and most transparent red herrings. You trot them out so fast and so often it is truly remarkable. For example, you say that the smart grid doesn't offer anything that can't be done presently. No, it doesn't. But what it does is use technologies we have to upgrade the abilities of the grid to manage distributed generation. The type of duplicity these two examples offer constitutes one of your core strategies for misleading people.
http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=5744688&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D5744688
Abstract
More battery powered electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs) will be introduced to the market in 2013 and beyond. Since these vehicles have large batteries that need to be charged from an external power source or directly from the grid, their charging circuits and grid interconnection issues are garnering more attention.
It is possible to incorporate more than one operation mode in a charger by allowing the power to flow bidirectionally. Usually, the bidirectional power transfer stands for two-way transfer of active power between the charger and the grid. The general term of sending active power from the vehicle to the grid is called vehicle-to-grid (V2G).
While plug-in electric vehicles (PEVs) potentially have the capability to fulfill the energy storage needs of the electric grid, the degradation on the battery during this operation makes it less preferable by the auto manufacturers and consumers. On the other hand, the on-board chargers can also supply energy storage system applications such as reactive power compensation, voltage regulation, and power factor correction without the need of engaging the battery with the grid and thereby preserving its lifetime.
This study shows the effect of reactive power operation on the design and operation of single-phase on-board chargers that are suitable for reactive power support. It further introduces a classification of single-phase ac-dc converters that can be used in on-board PEV chargers based on their power transfer capabilities in addition to the currently available surveys.
A 3.3 kVA on-board bidirectional charger is designed to experimentally demonstrate reactive power operation of the charger. A single-phase ac-dc active front-end boost rectifier and a half-bridge bidirectional dc-dc converter are utilized for the charger design. Also, a new controller for active and reactive power command following for EV/PHEV bidirectional charger is designed and experimentally demonstrated.
Finally, the cost of supplying reactive power is also important to effectively evaluate reactive power operation using chargers. There are two major impacts: one is on the converter design (incremental costs) and the other is on the operating electricity costs. Their combination shows the total effect and cost of reactive power operation and can be compared with other options of the utility grid to supply reactive power. Two customer scenarios are investigated to have two options of reactive power support. Level 1 and Level 2 reactive power support are evaluated separately.
http://www.ee.hacettepe.edu.tr/documents/Kiskacoglu_Seminar_31052013.pdf
Poor Dr.Greg/Pam. All hat, no cattle.
PamW
(1,825 posts)kristopher states:
Poor Dr.Greg/Pam. All hat, no cattle.
Considering the source; a person that is ALWAYS 100% WRONG; I guess I should be flattered.
Holding true to form, kristopher is also 100% in ERROR about reactive power. He has been commenting on the "reactive power" that will come from using V2G - vehicle to grid inverters, but all the while he has been oblivious to something very important:
Reactive power is a measure of something BAD!!!
Reactive power represents waste, inefficiency, and pollution of our power transmission lines.
Perhaps, kristopher can educate himself here:
http://wiki.answers.com/Q/What_is_reactive_power
which states beginning at paragraph 4:
In other words, if your electrical appliance contains inductance or capacitance, then electrical energy will periodically return to the power plant, and it will flow back and forth across the power lines. This leads to an extra current in the power lines, a current which heats the power lines, but which isn't used to provide energy to the appliance.
and
This undesired "energy sloshing" effect can be eliminated. If an electrical load contains both a coil and capacitor, and if their resonant frequency is adjusted to exactly 60Hz, then the coil and capacitor like magic will begin to behave like a pure resistor.
As stated above, the reactive power or "energy sloshing" is undesirable, and it heats the power lines, but isn't used to provide energy to the appliance. In the case of loads, the undesired "energy sloshing" can be eliminated, but not for sources like V2G inverters. V2G inverters will inherently be a source of inefficiency and disruption to the power lines. The papers that kristopher references deal with ways to minimize but not eliminate the undesirable reactive power.
Another analogy is due to Prof. Sauer of the University of Illinois, presented courtesy of the University of Wisconsin:
http://www.pserc.wisc.edu/.../special.../Sauer_Reactive_Power_Sep_2003.pdf?
The footnote at the bottom of page 3 gives another analogy for "reactive power":
Another analogy that says that reactive power is the "foam on the beer" is fairly good here because the space in the glass is taken up by the useless foam - leaving less room for the "real" beer.
All the while kristopher has been touting the benefits of "instantaneous reactive power" that will be provided by the V2G - Vehicle to Grid inverters. However, in reality "reactive power" is BAD - it denotes energy waste and inefficiency on the power transmission line.
What are you going to be hawking next kristopher; cola laced with "fabulous strychnine".
Why don't you restrict yourself to subjects that you understand, which leaves.....????
Again, where did you say you studied electric power engineering?
I thought NOT!
PamW
kristopher
(29,798 posts)Since I'm dealing with someone having no better arguments than falsehoods and trying to find 'gotchas' I guess I should have taken the time to write out "reactive power management" or "reactive power support".
I would have thought that anyone with the credentials you claim and who actually understands the potential role of battery energy storage to the distribution system would consider that verbiage unnecessary since the context was the ability of batteries to sell into a needed but as yet undeveloped "reactive power management" market for the distribution network much as there is an Ancillary Services market for transmission.
I didn't realize your limitations and shortcomings were so profound. My apologies.
PamW
(1,825 posts)kristopher,
I understand the potential of "reactive power"; as from V2G to COLLAPSE our power grid as Professor Sauer explains in his paper:
http://www.pserc.wisc.edu/.../special.../Sauer_Reactive_Power_Sep_2003.pdf?
starting on page 3 under the heading; How is reactive power related to the problem of voltage collapse, and that, quoting:
While there are "undervoltage relays", there are no relays in the system to directly sense the problem that the voltage is about to collapse
This threat to make the electric power grid more fragile and less robust has grown like topsy.
First, you add unreliable and intermittent non-dispatchable renewable power generators. In order to compensate for the failings and deficiencies of the non-dispatchable renewables; you have to add backup energy storage, as in terms of the V2G inverters. But the V2G inverters have their own failings and deficiencies in that they introduce "reactive power" and threaten voltage collapse. So the reactive power has to be mitigated by other add-on, and then the deficiencies of those must be addressed...
Rather than polluting a river, and then doing something to clean it, which has undesirable side effects, which must be cleaned up; and then there's the cleanup of the cleanup of the cleanup....; many environmentalists ask, "Why not just stop the original pollution?" Get rid of the stuff that creates the original problem.
I know very well the potential role of batteries; I see their potential of turning the electric power grid of the USA, one of the technical marvels of the 20th century, into a fragile and less robust power grid which more resembles the power grid of some 3rd world country.
That's the potential I see if we follow the ill-founded dreams of people who don't know the science behind the electric grid.
PamW
kristopher
(29,798 posts)Two articles on the use of V2G for reactive power support.
If you can't accept that evidence, then you are living in a world of fantasy and delusion or you simply have no grasp of the topic.
PamW
(1,825 posts)Kris,
I can read. In fact; I read the actual articles in the IEEE seminar.
However, although the techniques are clever; I don't believe they provide enough assurance against voltage collapse.
At least I have the scientific training and the degrees to prove it; to make my own assessment of scientific / engineering papers.
What are you going on; ideology?
Where was it again that you studied electric power engineering?
I thought NOT.
PamW
kristopher
(29,798 posts)Last edited Tue Jul 30, 2013, 01:08 PM - Edit history (1)
...and general horseshit as you try to hide the obvious lack of understanding. At least you're consistent - you start knowing nothing and end up proving you know less than that.
ETA: Just got this video in my email.
Inverters and Energy Storage Solutions Explained
http://www.renewableenergyworld.com/rea/video/view/inverters-and-energy-storage-solutions-explained?cmpid=SolarNL-Tuesday-July30-2013
oldhippie
(3,249 posts)PamW 1
kristopher 0
Where DID kris get that engineering degree?
kristopher
(29,798 posts)Times are tough all over.
BlueStreak
(8,377 posts)Last edited Tue Jul 30, 2013, 11:15 AM - Edit history (1)
after the nation has installed at least 50 times as much solar capacity as is currently installed.
And if we installed that much solar capacity in a nation that has essentially flat demand because of conservation, we would have LOADS of excess power, further making the issue a non-issue.
These executives are not stupid. They know that there is no issue whatsoever with solar in the mix at 1%, 2%, 5%, even 20% of our electrical supply. And by the time that we could install that much solar capacity (which would necessitate the shuttering of lots of nuke, gas, and coal plants -- which isn't going to happen very quickly because of the politics of plant ownership), we will have good technologies to store the excess power to smooth the cycles.
Why are you even arguing about this? It is ridiculous. You are arguing about a scenario that cannot possibly happen for 25 years, and then only if we do absolutely nothing to prepare for that.
kristopher
(29,798 posts)Pam/Greg has been kicked off the board once for his outrageous behavior, but he's dedicated himself to harassing me in an effort to make posting so disagreeable that I'll leave.
It isn't going to happen.
ETA: P/G claims to be a scientist, so here is a sample of the way he thinks. You decide if the values displayed are consistent with the values required for the pursuit of 'science'.
PawW/Dr.Greg's claim:
If electric generation is predominantly intermittent renewable power, using natural gas to firm the power would likely result in greenhouse gas emissions that would alone would exceed the 2050 target for the entire economy.
However, the report then says:
"Thus, development of a high percentage of intermittent resources would require concomitant development of zero-emisions load balancing (ZELB) to about (sic) these emissions and maintain system reliability. ZELB might be achieve with a combination of energy storage devices and smart-grid technology."
Making the complete quote this:
If electric generation is predominantly intermittent renewable power, using natural gas to firm the power would likely result in greenhouse gas emissions that would alone would exceed the 2050 target for the entire economy. Thus, development of a high percentage of intermittent resources would require concomitant development of zero-emisions load balancing (ZELB) to about these emissions and maintain system reliability. ZELB might be achieved with a combination of energy storage devices and smart-grid technology.
Now I ask, is A even remotely similar to B when being used to support this claim?
A:
B:
http://www.democraticunderground.com/112748437#post37
BlueStreak
(8,377 posts)Going back to the OP, it is clear that the big power companies have moved on. The last thing they ever wanted to see was a highly distributed generation system (PV shingles on every house) because that would theoretically put them out of business, leaving them nothing but the grid.
But realistically that isn't happening in any big way -- and they simply aren't worried about that anymore. In many cases, they have successfully got the laws rigged so that even if an individual generates surplus juice, the power company buys it more cheaply than they pay to generate electricity from coal or gas. And the big numbers aren't coming from mom and pop. They are coming from major solar and wind installations, many of which are controlled by these same power companies. And that's just fine. Regulated utilities have served the country well over the years, as long as the regulation is effective. And we need the muscle of big companies to make a real dent in the carbon numbers.
That part of the picture is looking very, very good (i.e. the wind and solar generation, as well as the grid improvements.) The part that is still a problem is the fact that we have an entrenched nuke and coal industry that will be very hard to displace. There are two basic facts that most people aren't aware of, and they are crucial:
1) Thanks to conservation, the US has been very nearly flat in its electricity consumption over the past 5 years or so.
2) We are bringing on new wind and solar capacity MUCH, MUCH faster than our national demand is increasing.
Add those two together, and there is absolutely no compelling reason ever to build (or extend) any nuclear or coal plant -- ever. Only political reasons.
kristopher
(29,798 posts)That is almost word for word what the recently retired Chair of the Federal Energy Regulatory Commission said in an interview.
"No new nuclear or coal plants may ever be needed in the United States… renewables like wind, solar and biomass will provide enough energy to meet baseload capacity and future energy demands"
link to video:
http://greenmonk.net/smart-grid-heavy-hitters-jon-wellinghoff-chair-of-us-federal-energy-regulatory- commission -part-1
http://greenmonk.net/smart-grid-heavy-hitters-jon-wellinghoff-chair-of-us-federal-energy-regulatory- commission -part-2
It's in the second half of the interview (the second link).
"Why it is a good thing for utilities that customers consume less electricity – 0:36
How smart grids help increase the penetration of renewables on the grid – 2:12
How electric vehicle owners are being paid up to $3,600 per annum to provide regulation services for utilities while charging! – 2:54
How renewable energy sources can be used as baseload power (no coal or nuclear baseload need ever be built) – 4:34"
Read more: http://greenmonk.net/smart-grid-heavy-hitters-jon-wellinghoff-chair-of-us-federal-energy- regulatory-commission-part-2/#ixzz1Jngo06xQ
BlueStreak
(8,377 posts)Let me say it one more time, just so people understand the simple truth.
1) Our national electricity demand has been nearly flat for the past half-decade due to conservation. There is no reason to believe demand will suddenly shoot up. Conservation efforts are ongoing.
2) The amount of new electricity we are bringing on to the grid every year is 100 times greater than any possible increase in national electrical demand. Therefore if we leave the existing production in place, we will end up with far more electricity than we need.
SO that means:
a) We NEVER have to build another dirty plant (with dirty meaning coal, natural gas, or nuke). Not this year. Not next year. Not ever.
b) We can start the decades-long process of shutting down the dirtiest and most dangerous plants. And we can start this today.
wercal
(1,370 posts)Doesn't evert battery have a finite number of charging cycles, before failure? If I owned an electric car, with an expensive battery, there is absolutely no way it gets used to power the grid.
I think too many people minimize the cost of battery storage...always relying on some future breakthrough that we don't have right now.
kristopher
(29,798 posts)It adds another layer of value to the battery that the EV owner is paying for. The way it works is that the car is programmed to "buy low" and "sell high" within a range set by the driver allocating capacity excess to driving needs as available for sale.
Power for ancillary services to the grid is some of the most expensive on the market, so the return available to the EV owner is potentially very high. Depending on the way the market develops the value of the electricity sold is estimated to be significantly more than the wear and tear on the battery.
No one will require you to participate, it would be strictly a choice; but it is one of those choices that is pretty much a no brainer once you have the numbers in front of you.
wercal
(1,370 posts)You are talking about a 'time of day' pricing structure that does not exist yet in most areas....so I don't have a firm basis of numbers to run. But, I'll assume the difference in wholesale vs retail in power where I'm at - 4 cents per kwh.
Using a 16 kwh Volt battery, which I believe can be completely discharged and recharged twice in one day, using the 14 kwh available for this. If I had my car plugged in all the time and never drove it, I would make $408.80 a year.
Since the warranty for these batteries is 8 years, I can assume that's about its serviceable life...8 years equals $3,270 in 'profit' from the power company. The batteries currently cost double that.
But I didn't need to run any numbers.
Seriously, ask yourself this question:
Why would the power company pay me more to use a battery than what it would cost them to buy their own battery?
The reality is that they won't. The only reason for a power company to use V2G is to pay a car owner LESS than what they would have to pay to own...which by definition means the car owner gets a raw deal.
I would neeeever do this. Now you believe its a 'no brainer'....so I assume you have run some numbers?
kristopher
(29,798 posts)It is the provision of ancillary services that is where the money is.
Since the time of day assumption you've taken isn't applicable, we can skip over that, but to address a couple of other questions:
The utility could and will buy storage. But the availability of a huge existing base of storage can't be ignored. The way the economics work is that the consumer pays for a car for transportation and makes the economic valuation on that basis alone.
But the batteries are expected to outlive the rest of the auto.
The use that the utility puts the battery to one where only a little is taken, there wouldn't be cases where deep discharges occur.
That means wear and tear isn't nearly what you might imagine.
When you stack that up against the value of ancillary services, the owner can come out (depending on assumptions) between $1500-$3500 per year to the good IIRC (I haven't read those research papers in several years).
Some survey work has been done where the numbers were presented and the extra layer of financial benefit that the EV owner can realize is generally very attractive.
The numbers have been run by several entities from utilities like PG&E and grid operator PJM to battery makers, electric car companies, NREL researchers and academic researchers.
You might try googling "Willet Kempton V2G" the whole thing is his idea and he offers most of his published papers on his University of Delaware website.
The Federal Energy Regulatory Commission (FERC) is the regulatory body responsible for the operational security of the nation's energy delivery systems. They are 110% behind widespread adoption of V2G.
wercal
(1,370 posts)"The use that the utility puts the battery to one where only a little is taken, there wouldn't be cases where deep discharges occur. That means wear and tear isn't nearly what you might imagine." I'm not sure why you are attributing more wear to 'deep discharges' than 'where only a little is taken'. The battery and car already protect themselves from a damaging discharge...and all discharges are equal. In aggregate, discharging and recharging 1 kwh a day for two weeks is exactly the same wear as one 14 kwh discharge in 12 hour period. But none of that matters anyway, as my example was only intended to demonstrate that the huge profits you see from selling battery power just aren't there....assuming maximum depletion/recharge 'opportunities' to make a 'profit'. If you want to reduce the discharge, the 'profit' is just thinned out.
"When you stack that up against the value of ancillary services, the owner can come out (depending on assumptions) between $1500-$3500 per year to the good IIRC (I haven't read those research papers in several years)." This is where you really need to back yourself up with numbers. Using that Volt battery, charged twice a day every day, a $3,500 'profit' implies a cost differential of 34 cents per kwh. Since it only costs 12 cents retail in the first place, where on earth are you going to get that differential? It just doesn't add up, and you shouldn't make such fantastical statements without backing it up with calculations. And no, I'm not going to go on a Google hunt...you make the claim, you should prove it.
Now you have poo-pood my notion that the cost differential is based on 'time of day' power price differentials...and vaguely talked about 'ancillary services'. So...where's the beef? How does an electric car owner get paid for selling battery capacity? And how on earth is it valued at 34 cents a kwh, which is almost triple the cost of power in the first place.
Pretend I am a car owner, who you are trying to convince to do this. Don't tell me too Google a study. Tell me why I should use my valuable battery life in terms that don't make me feel like a vacuum cleaner salesman is glossing over the fine print.
V2G is just a huge turn off to me...its perfect for 'dreamers', but I just don't see it ever happening in reality. (btw, my qualifications include being 1) and engineer and 2) a consumer and 3) an amateur auto mechanic). The very idea is predicated on a flawed notion of large scale penetration of electric vehicles into the auto market, which is not supported by current sales trends. But even if that happens, the next step involves conning car owners into participating...again, the power company only uses V2G if its cheaper than owning their own batteries, which means the car owner gets burned.
Fast forward 25 years from now - I guarantee you V2G will still be a novelty that a few people participate in, and it will have an almost immeasurably small impact on our electrical system. How do I know this with such certainty? Well, we each use 13,600 kwh per capita, per day....we have less than one vehicle per capita, but we'll make it one to give V2G the benefit of the doubt and simplify things. That means that a Volt could supply 0.21% of my daily energy needs. Is that really enough to serve as a buffer for intermittent power sources? How about a Tesla...85 kwh five times a day...3.13% of my daily energy needs. Even if the entire nation's vehicle fleet were top of the line Teslas, with rapid chargers, and we added another 60 million cars so there would be one per capita, V2G would only provide 3.13% of our daily energy needs. No study in the world is going to change that reality.
FBaggins
(26,714 posts)Hybrid/EV batteries don't "outlive" the car as batteries for the car... they lose too much utilitiy after many charge/discharge cycles and their effectiveness dramatically declines.
But that doesn't mean they become useless. A battery that declines from being able to power an EV for 100 miles to only, say, 40... is still potentially quite effective in a home storage / load-shifting role.
wercal
(1,370 posts)The idea that you could sell your used battery to a utility company, to be incorporated into a bank of batteries.
But that is not what is being discussed here at all.
The subject at hand is 'Vehicle to Grid'...(ie the battery is still in a vehicle) where an unwitting electric car owner sells some of his battery's serviceable life to the power company.
BTW, the notion of selling your old battery to the power company may be somewhat flawed, as you may be able to get an equal amount of money as a 'trade in' where a new battery is purchased.
oldhippie
(3,249 posts).... you refuting his arguments.
Stand by for obfuscation, deflection, and being deluged with links to all his favorite *kris approved* websites backing his positions, in 5.....4.....3....2....1....
wercal
(1,370 posts)kristopher
(29,798 posts)That's fine. You also say I need to come up with some numbers - no I don't. really don't care if you want to participate in V2G markets or not. You've clearly made up your mind to reject the idea, and in spite of me giving you a point of entry into the research (Kempton) you show no inclination to educate yourself.
Yes, generally speaking, indications in the research are that the batteries are going to outlive the car as a propulsion unit - even with V2g. They will then probably have further utility as either replacement batteries in older cars or as stationary storage for energy, such as solar in homes or in large banks by corporations or utilities. Again, I really don't care if you accept that or not.
And frankly, your extremely impressive credentials notwithstanding, I'll take the information I've gleaned from talking directly to the involved researchers and large body of both published and unpublished literature available on the topic. For example, the norm for the for EV battery technology is, at present, 10,000 charge/discharge cycles. And developers are going beyond that. That is what, about 27 years worth of daily charging? And no, I'm not going to google "EV 10000 cycles" for you.
One final point and then I'll leave you to wallow in your contrariness - the idea that the battery must necessarily lose capacity over time is also one that is quickly becoming obsolete.
TTFN
wercal
(1,370 posts)Am I really wallowing in 'contrariness', as you claim...or am I just the ants at your picnic, with real world calculations.
You still haven't answered one very basic question: How do you make money on V2G?!?! What to you get paid per KWH, and who the hell pays it?
I suspect you aren't answering because you really don't know....
...and that should be your first clue that you shouldn't be making so many wild claims about the subject.
So how about it - how much will V2G pay the hapless sap who agrees to it?
BlueStreak
(8,377 posts)If I am Toyota, I don't cover any battery that is getting extra cycles just sitting in your garage.
The only scenario that makes sense to me is that the EV owner could make a choice to charge immediately at the market prices, or let the utility decide when to charge up (sometime overnight) and give me a break on the rates.
kristopher
(29,798 posts)V2G is going to require a bidirectional charger (bdc), not the unidirectional ones that are standard now so it isn't like the mfg isn't going to be part of the program.
Perhaps they could warrant the batteries and recoup the cost by marketing their V2G tech in bidirectional chargers through utilities. Then it becomes part of the utilities "sign up" incentive, like a cable box.
Or through coordination between mfgs and national regulators they make being V2G compatible equipment a standard part of every EV and work out a standardized, legislated process for warranty coverage. After all, there is strong national regulator support for V2g (see that video again) so I'd guess there will at least be action in that direction.
Or, maybe warranty coverage for V2G usage is an option sold to the EV owner through dealers or sold/provided through the utility.
However, if the customer can reduce ownership cost by providing high value added grid support with Mfg Alpha's vehicle, but Mfg Omega wants to charge extra for warranty coverage or not offer coverage at all, which Mfg will have a sales advantage?
Interesting, as you said.
BlueStreak
(8,377 posts)Last edited Wed Jul 31, 2013, 09:53 AM - Edit history (1)
The type of battery used in cars is not what the utility needs. They can put in their own, more scalable batteries at much lower cost than using the customer's batteries. In particular, flow batteries look like they should be very scalable for a utility substation where space is not a big limitation.
And no way I ever want electrons taken out of my car battery -- ever -- no way nohow. I want that battery at full charge any time I want to drive it. I don't care what incentives they offer, they aren't going to run down my battery. Why would I even have an EV if I couldn't count on having a full charge?
This is as goofy as that concept of intercontinental travel through maglev vacuum tubes. A bunch of nerds with way too much time on their hands and not a lick of common sense among them.
Now, the idea of having the option to charge my battery at off-peak times of the utility's choosing -- that makes sense -- as long as I can override that if I see a need to get a quick charge.
kristopher
(29,798 posts)Are you of the opinion that they drain them dry?
What if you could sell gasoline out of your tank and make a couple of thousand dollars per year? You can set it to keep however much you want in the tank, and most times it will have nearly as much or more gasoline in the tank as when you parked it, but you'll get a healthy check for the utility having used it.
Would you sell them gasoline?
I think part of the reason you are skeptical might be that you aren't familiar enough with the mechanics of the electrical system and perhaps don't appreciate the amount of potential power that the vehicle fleet represents. Consequently you seem to have a vision of massive draw requirements foisted onto a very limited amount of storage capacity.
You may want to look into ancillary services and reactive power (there is no market for reactive power support yet but it is a niche that has demand that will increase with renewable penetration). The way V2G is most valuable is as a stabilizing tool and when used that way it only takes sips of electricity and puts them back almost immediately. There are other services that will be be part of the program, but they won't pay as much for that power.
Remember, there are 200+ million registered light duty passenger vehicles in the US and at any given time and they are parked 20+ hours per day. You can play with the amount of available power at different penetrations of EVs and differing levels of participation to see what you come up with. For purposes of electric policy, as I recall, if 5% of an electric fleet is participating, any stability problems associated with a distributed generation grid is largely eliminated.
There is a lot of information on this online. ETA: Just found this:
How People Use Their Vehicles: Statistics from the 2009 National Household Travel Survey
http://research.microsoft.com/en-us/um/people/jckrumm/Publications%202012/2012-01-0489%20SAE%20published.pdf
wercal
(1,370 posts)"Remember, there are 200+ million registered light duty passenger vehicles in the US and at any given time and they are parked 20+ hours per day. You can play with the amount of available power at different penetrations of EVs and differing levels of participation to see what you come up with. For purposes of electric policy, as I recall, if 5% of an electric fleet is participating, any stability problems associated with a distributed generation grid is largely eliminated."
Ok, 5% of 460 million vehicles is 13 million...assume they all are top of the line 85 kwh Teslas that could cycle 4 times in a 20 hour period...that is 4.4 billion kwh.
Our nation uses 3,800 billion kwh a day.
So please explain to me how an energy sink that represents far less than 1% of our daily use makes this statement true:
"For purposes of electric policy, as I recall, if 5% of an electric fleet is participating, any stability problems associated with a distributed generation grid is largely eliminated."
You can't.
Heck, if you assume the entire vehicle fleet is electric, it still represents 2% of our energy use.
I don't think you have any idea of the scale of our electrical system...or any idea of how inefficient battery storage is. But you keep selling the snake oil.
BlueStreak
(8,377 posts)I do not accept that there is ANY storage problem when the intermittent renewables represent 5% of the supply, but certainly it can become an issue at some much higher level. And as you point out, the numbers are enormous in scale. Dinking around with car batteries is a complete waste of time -- a preposterous business and technical proposition.
More diversity of generation sources (waves, offshore wind) wil help. To make a serious dent in the storage problem you need something that can operate at a large scale. Flow batteries have this potential because they can scale to whatever size electrolyte tank you want to build. Pressurized air apparently works in certain geological situations. Pumping water uphill into reservoirs is scalable. There is some thought that specialized flywheel systems can be part of the solution. These are the things that serious thinkers are working on.
I don't believe it is a 2016 problem or even a 2020 problem. Maybe by 2025 it is a problem. It is a good problem to have because it means we will have made significant progress getting rid of carbon generators.
wercal
(1,370 posts)Another solution to intermittent problems is a better transmission system...so the wind doesn't have to necessarily be blowing near you....as long as its blowing somewhere.
Another (very inefficient) solution is using excess power to get hydrogen from water...and use the hydrogen as a fuel source when the wind stops blowing or its a cloudy day.
The pressurized air is intriguing. There are massive caverns cut out of salt deposits near Hutchinson, Kansas...and much of the region's natural gas supply is stored there (when you hear reports ahead of winter about 'gas supplies'...the report is referring to storage facilities like this). Its tremendously more cost efficient than building steel tanks or something similar. So I could see compressed air being stored in a similar situation...and maybe the heat let off during compression could be recaptured.
Or we could use every parked car, letting the air out of the tires to turn an impeller, but only use a little of it, and quickly air the tire back up. Oh wait...
BlueStreak
(8,377 posts)I don't know that the process of making hydrogen is that much less efficient than other storage schemes. You lose energy in all of these systems. Maybe hydrogen is a bigger loss than others, but it has a big advantage. The stored hydrogen can be used to power fuel cells, so there can be a dual purpose in converting excess energy to hydrogen. That would seem to offset the disadvantages of energy loss somewhat. In other words a storage medium that has multiple uses is intrinsically more valuable than a medium that can only really be used to put energy back into the grid.
wercal
(1,370 posts)...but a lot of that is heat, which could be captured for use. There are lots of experiments with catalysts to increase that efficiency...but I don't know if any of those could be economically scaled up to size.
I looked up pumped storage hydroelectric, and its 70-80% efficient:
https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity
Here is a version in the US:
https://en.wikipedia.org/wiki/Ludington_Pumped_Storage_Power_Plant
Biggest problem is that it takes a lot of real estate.
BlueStreak
(8,377 posts)If pumped storage is already cost effective, when using fossil fuels, it can only become more attractive when using wind and solar. If plants can absorb a 20% efficiency loss today and still make it worthwhile to run those systems powered by coal or gas, it becomes an economic no-brainer when the original electricity is essentially free (variable cost-wise).
But whether it is compressed air or pumped storage, you can't just do that anywhere you like. It would be hard to find good sites for pumped storage in the great plains, and there are limited places where compressed air will work.
Diversity is the answer. Diversity in generation and diversity in storage systems.
BlueStreak
(8,377 posts)These are the same people that fight like hell if a municipality tries to pass a law saying that they have to buy any excess electricity I produce, even if they only have to pay me one-fourth the rate that I have to pay them for electricity.
And no, if anybody tries to take gasoline out of my tank, I'm going to shoot them (*), even if they are holding a wad of cash. I put the gas in my tank for a reason -- because I need to get somewhere.
Re: draining the battery dry, what's the difference? If I have a vehicle that will go 50 miles on a full charge. I have to be able to count on that. If I know I have a 40-mile round trip the next morning, I will take the EV and give the gas car to my wife if she has a longer trip. And then I go out to my garage and find I'm only good for 35 miles? What kind of nonsense is that? These people are idiots if they thing that is going to fly.
* I don't actually have a gun, but I'd be angry enough to shoot them. That's why I don't own a gun.
kristopher
(29,798 posts)Then don't participate. No matter the screen name you use, you clearly don't care to judge the program by its merits. When you totally ignore the information presented in favor of baseless ignorance, then you remain ignorant.
TTFN
BlueStreak
(8,377 posts)Come on, man. You need to get a grip. I agree with you on some of these things. On others, I disagree. But I don't have a twin.
wercal
(1,370 posts)person.
But here we have yet another oppurtunity for Kristopher's self improvement.
You have made a baseless statement on the internet.
Ok - prove it.
If you can't...dont make the statement.
I hope you can translate this lesson to your other posts.
oldhippie
(3,249 posts).... or you may be banned from the group, as PamW just was. Don't run afoul of the "editorial control."
wercal
(1,370 posts)I just checked Pamw...and as far as I can tell, its still an active username? 
oldhippie
(3,249 posts)And PamW has not been PPRed from DU, but has been banned from this group (E&E).
Go to "About this Group" tab and scroll down to the bottom of that page to see the members that have been banned from E&E.
wercal
(1,370 posts)Pamw seemed to have a wealth of knowledge on the subject....I guess that's not allowed.
wercal
(1,370 posts)"This is as goofy as that concept of interconntinental travel through maglev vacuum tubes. A bunch of nerds with way too much time on their hands and not a lick of common sense among them."
quadrature
(2,049 posts)if the cost to the grid of renewables is
low enough,
the technical issues are manageable.
kristopher
(29,798 posts)Open Access Article
Abstract
We model many combinations of renewable electricity sources (inland wind, offshore wind, and photovoltaics) with electrochemical storage (batteries and fuel cells), incorporated into a large grid system (72 GW).
The purpose is twofold:
1) although a single renewable generator at one site produces intermittent power, we seek combinations of diverse renewables at diverse sites, with storage, that are not intermittent and satisfy need a given fraction of hours. And
2) we seek minimal cost, calculating true cost of electricity without subsidies and with inclusion of external costs.
Our model evaluated over 28 billion combinations of renewables and storage, each tested over 35,040 h (four years) of load and weather data.
We find that the least cost solutions yield seemingly-excessive generation capacity — at times, almost three times the electricity needed to meet electrical load. This is because diverse renewable generation and the excess capacity together meet electric load with less storage, lowering total system cost.
At 2030 technology costs and with excess electricity displacing natural gas, we find that the electric system can be powered 90%–99.9% of hours entirely on renewable electricity, at costs comparable to today's—but only if we optimize the mix of generation and storage technologies.
Full article available http://www.sciencedirect.com/science/article/pii/S0378775312014759
BlueStreak
(8,377 posts)You wouldn't build 20% more coal of nuke plants than you need because you would still have huge maintenance and fuel costs. But with wind and solar, there are no fuel costs at all, and most of the money is initial capital (plus some ongoing maintenance). Because of this, there is no reason to try to plan for 100% capacity. It is no big deal to plan for 105% or 110% and simply not use the juice when you don't need it. You didn't pay anything for the wind or sun, so if you have to dump those electrons, you haven't lost anything.
And if you go for 110%, it is almost impossible to have a load balancing problem. Instead of dumping the excess, you can turn it into hydrogen to power fuel cells. Or you can use it to run desalinization plants, filling up large storage containers with fresh water during times of excess power.
FBaggins
(26,714 posts)If you actually read the "study" (really an exercise in backfitting) kris linked, they actually have to target closer to 300% in order to come close to meeting the demand. Not 105% or 110%. And even then... they really fail.
But it's wrong to say "it's no big deal" because the initial capital isn't something you can ignore. That's like saying that you can increase the reliability of a Yugo by buying three of them. So when one breaks down, you still have a working car available.
As you start to hit at the end of the post, the solution is more flexible demand and more robust storage systems... no dramatically overbuilding.
BlueStreak
(8,377 posts)Yes, if we wanted to generate everything entirely from wind and solar, then 100% isn't nearly enough. No question about that. But the reality is that we have LOTS of other sources, including hydro and geothermal, which are very predictable, in addition to the dirty sources that will not be phased out overnight. Even n the most aggressive scenario, we'll still have some nukes and a lot of coal/gas plants in operation in 2040. Not because we will need them, but because those are powerful industries with a lot of political power.
That being the reality, there simply isn't any leveling problem in the next 25 years.
The problem with these academic studies is that most of them talk in the abstract instead of talking about a practical course that reflects our political realities.
kristopher
(29,798 posts)"Talking in the abstract" isn't a problem. It is an essential part of solving problems. It is studies like the one referred to that give us the boundaries to guide our future efforts. For example, no matter what percentage of overbuilding occurs when we limit our selection of resources to wind and solar, we know that the end result can be accomplished economically - delivering electricity at a price comparable to what we have today.
The next step involves improving on that with whatever local resources are most suitable - an act that may be done by an expanded large scale modeling effort following on the method in the solar/wind study, or it may be a large number of market driven studies of specific profit opportunities as they present themselves. But make no mistake, a lot of the people who will be involved in making the transition to carbon free energy happen are aware of that study and its implications.
