Lots of interest in energy it seems on this Silent Fitzmas Eve.
So, high time I reformatted
this for DU.
Let's turn the "get off the grid" discussion upside-down, shall we?
It's nice to see people actually looking at improving power in their house... most people focus on vehicles, which is understandable since gas prices are something we have to face up to on a weekly basis or worse. Our home energy bills, though, only hit us once a month and often someone else in the household handles them. We don't get the jolt as often.
In addition a lot of folks focus on electricity. While your electricity bill may be higher, here are some very good reasons why your attention needs to be on hot water, winter heating, and air conditioning instead.
You shouldn't try to get off the grid... yet.
Let's take a look at where our energy goes in the residential sector:
...most of it to HVAC and water heating.
Even when we look at just electricity use, ignoring oil and natural gas:
...still a good portion of what we do with electricity is turn it into heat or cold.
I know, yawn, right? Don't give up on this post yet. These may just be graphs to you but these numbers have huge consequences both to your own wallet and to the and to the environment and economy.
Here's why:
- No technical "fix" is needed for renewables here. The technology to utilize both sun and ground heat is, well, at least as old as glass and rubber (in fact even older.) Yes, there are technical innovations that help -- high admittance glass, vacuum heat tubes, freeze-proof rubber tubes, better heat pumps -- but people have literally been doing these things for ages. Heck, even cavemen knew how to use caves to keep warm/cool, (not to offend the cavemen.)
- There is a fast payback on these systems. You can take out a home equity loan and the savings from the system will most often pay its own interest for the life of the loan, as well as add equity value to your house (you just have to get an evaluation by someone qualified to estimate the system.)
- The basic engineering is so simple that your random backwoods "Cooter" type regularly builds their own from scrap. The Internet has plenty of pages describing home-built systems, and that's just the guys who own a computer.
So what are these technologies? Well, I would be remiss if I didn't mention that before you bother with installing a special system for HVAC, you can get more return on your dollar by general efficiency improvements -- better insulation, large south facing "Heat Mirror" windows with a tree or awning, ceiling fans, economy shower heads, and if possible a duct from the top ceiling to the bottom floorboard to blow risen hot air down for reuse before it floats out the attic. Don't neglect these things.
But anyway, the two major technologies to be looking at for a quick payback these days are solar hot water and geothermal heat banking/heat pumps.
Solar hot water is the cheaper option of the two. Maybe you are tempted to scoff that this will not make a signifigant dent -- untrue. Look back up at the chart. Water heating represents 16% of our average energy use. Economy shower heads looking a bit less silly to you now?
Solar hot water works best when combined with an upgrade to an old water heater -- just the upgrade itself (to either tankless/minitank or to point of use tankless) can be well worth doing. But since you have the plumbing torn out anyway, and in some cases you have a spare old water tank from your old system available for free, it is a good time to think solar.
Unlike PV electric panels, solar heat panels collect a lot more useful energy (when "useful" means heat.) That's because it is fantastically easy to convert sunlight to heat -- all you need is a black surface and a glazing that traps heat radiation. They also have less issues with reduced output on cloudy days than PV panels. Many solar hot water installations even have to have built-in measures to prevent overheating.
If you don't try to cover all your water heat needs, a solar water system can be installed for a few thousand dollars.
http://www.solarroofs.com/ (just one of many links, no endorsement implied.)
DIY is not recommended for your average suburbian/exurbian home, though, if you do not have time to learn about these systems thoroughly... practically becoming a pro yourself... there is a lot that can go wrong.
http://www.fsec.ucf.edu/Solar/apps/sdhw/trouble.htmThe second technology helps with indoor heating
and air conditioning and is known variously as a "ground source" system, a "geothermal banking" system, a "geoexchange" system, or a "heat pump" system (though not all "heat pumps" are "geothermal".) A brand name "slinky coil" is also helpful when researching them.
But wait, wasn't the subject of this post "solar power"? Yep, I only did that so you'd look.These systems range from $10K to $30K depending on many factors about your house, your lot of land, where you are, and your current heating system. They are pretty much turnkey systems and would be very difficult to DIY properly, so consult a well recommended professional.
Essentially these systems bring the age-old cave up to you, so you don't have to live down in it.
(Oh, and a preemptive please, no comments to the tune of "that's not geothermal" -- the term is regularly used for both heat banking and deep drilling by people in the industry. Times change, and so do words.)
http://www.waterfurnace.com/ (again, no endorsement implied.)
Now some bad news. The market is full of gougers. You'll find various companies charging a wide variety of prices, and some of them are unconscionable rip-offs.
In fact, there is a technology I skipped here and the only reason I skipped it is that it is impossible to buy it at a reasonable price: Solar air heat. As a DIY project solar air heat can be very inexpensive and with a good amount of scavanging for salvage, I would not be surprised if one could not manage payback periods of less than a year.
I've written about this before, and you may want to check out this link where a small-volume local operation is actually bothering to fabricate solar air units at a decent price:
http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=115&topic_id=31258&mesg_id=31258...but look at what some of the other people are charging:
http://www.solarunlimited.net/prices.htmlhttp://shop.altenergystore.com/items~Cname~Solarsheat+Recirculating+Air+Heating+Sys~Cc~SOLARSHEATG~iTpStatus~0~Tp~~Bc~.htmhttp://shop.altenergystore.com/items~Cname~Cansolair+Recirculating+Solar+Air+Heater~Cc~CANSOLAIR~iTpStatus~0~Tp~~Bc~.htm...shameful. That last one is even made out of soda cans -- recycling is nice and all but not at over a grand!
Granted the above systems are nice and large and have all the needed gizmos included, but a message to people in this business -- it isn't supposed to be about charging the customer a large percentage of what they would save (or in republi-speak "what the market will bear") but making enough profit to sustain the business and scale up production. The mere presence of products so grossly overpriced is bad for the renewables business, scaring off potential customers.
As an aside, another "no duh" technology that sounds simple but is not even available anymore, AFAIK, nevermind cheap, is a refrigerator that uses outdoor air when it is cold. Go figure.
http://www.sunfrost.com/passive_refrig.html Or how about holding bathwater for a short time after use in a drainage tank so it heats the house. Or preheats clean water.
If we were smart about heat, we wouldn't use a lot of the power we consume today. The question is definitely not "do we have the technology"? The questions are "do we have the will?" and "do we have the clout?" to get this done on a massive scale.
Further reading:
http://www.eere.energy.gov/consumer/http://www.pathnet.org/sp.asp?id=13076Finally to address electricity, the following is extremely graphics heavy, but gives you a quick look at energy savings including the "watt":
http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=115x28899