The definition of "baseload power plant" seems to be evolving.

[kristopher]

Apparently it is now one which load shapes around wind and solar...
"Another plus is that geothermal power, while renewable and low-carbon, can provide baseload electricity. That means it can be used to back up intermittent sources of renewable energy such as wind and sun."

Geothermal energy could meet a fifth of UK's power needs – report
The study found that subsidising geothermal technology initially would help to bring down costs rapidly as UK sites were developed

Fiona Harvey, guardian.co.uk, Wednesday 30 May 2012 13.52 EDT

...the report found that the current subsidy regime does not provide sufficient incentive to develop the technology in the UK - even as Charles Hendry, minister of state at the Department of Energy and Climate Change, flew to Iceland on Wednesday afternoon and signed a Memorandum of Understanding with his Icelandic counterpart Oddný G. Harðardóttir to explore a possible new interconnector that could be used to import geothermal electricity from the country's volcanoes.

Geothermal power stations use water pumped down to hot rocks under the earth that returns to the surface heated, fuelling electricity generation or to be used for space heating.

There are promising sites for geothermal power spread throughout the UK, from Cornwall to the Lake District, East Yorkshire, Northern Ireland and Scotland.

Another plus is that geothermal power, while renewable and low-carbon, can provide baseload electricity. That means it can be used to back up intermittent sources of renewable energy such as wind and sun. The study found geothermal could supply 9.5GW of electricity, about 20% of current demand, but also 100GW of heat, which would be enough for the whole of the UK's space heating needs. The government has struggled to encourage the take-up of renewable forms of heat, such as wood-fired boilers and underground heat pumps.

However, geothermal power receives a relatively low level of subsidy

http://www.guardian.co.uk/environment/2012/may/30/geothermal-energy-uk-power

[denverbill]

1. They should pump sea water down and create potable water at the same time.

I'm not sure if geo-thermal power is 'renewable' though. I know for all intents and purposes, it isn't getting used up any time soon, but the earth is gradually cooling.

[FBaggins]

3. Very clever, but probably not an option.

If you want to desalinate water by boiling, you maintain a careful temperature at the boiling point of water (but below that of anything else in the water that you don't want extract)... that's tough in a geothermal scenario.

More importantly, doing so would mean that you're pumping tons of salt down the hole and not taking it back out. That's going to clog things up pretty quickly.

And then most importantly... salt water is corrosive (and really hot saltwater is even more corrosive). This is why we all know that they had given up on saving the Fukushima reactors the moment they decided to start cooling attempts with salt water. That's not insurmountable if you plan for it, but it increases the cost of your materials (salt-resistant concrete, titanium, etc)

[FBaggins]

2. A bit of a stretch.

They've really cobbled together two different advantages of geothermal into one sentence. It's a baseload option and it could be a great option for backing up more variable renewables. Geothermal and Hydro both fit this model (solar/wind backup) well because they are reliable, can be turned on/off in a comparatively short time (and run at partial capacity), and have very low fuel costs.

It could do very well in areas where pumped hydro is not an option.

On edit - Of course I have to ask why would you use it this way? If you're going to use it to even out fluctuations in wind/solar generation, that nucessarily means that it has to generate less power when those alternatives are doing well, and then power up when they're generating less. Once you build a facility that can run 24/7 and has essentially no fuel costs... why would you ever turn it off/down? You would obviously do that with pumped storage, or even large hydro in areas where they might not have enough water to run year-round... but why would you not use geothermal whenever the plant was in service?

[kristopher]

4. "Cobbled together"? That is how language evolves.

I don't think the author has made a mistake - I've often said that "baseload" as it is used to define a power plant, is an economic concept, not a technical requirement for delivering power. The usage is consistent with that view.

Why would you use geothermal this way? Because it is less abundant than wind and solar and it proves more expensive power relative to W&S's eventual cost. The new technology that is being tapped into isn't able to be depleted as we understand the term, but it is able to be overused, which requires that particular well to sit idle for some prolonged period of time while the surrounding rocks reheat.

The value of the geothermal resource being discussed - as well as of the small scale hydro that hasn't been exploited - is both the load following capability offered (as you described above) and the fact that they are so widely distributed that they offer a standardized solution that scales.

[RobertEarl]

5. Baseload is an economic concept

Indeed, it is economic$.

Centralized power is about economics. Refusing to see its dangerous emissions, due to its bastardized focus on profit based economics, it is destroying the environment.

[FogerRox]

6. My understanding is California gets 5% of electricity from

geo thermal, 24/7/365.

[kristopher]

7. This is a different type of geothermal system.

Google /EGS geothermal/