Talk:Geothermal energy

Earthquakes

doesn't show much inddication of credible opinion of causaulity. All that is provided is a link to an earthquake map that shows lots of earthquakes near a geothermal plant. Correlation does not prove causaulity or the direction of causality, if it exists. But does geothermal water injection cause earthquakes or are earthquake zones prefered sites for geothermal plants (seismic activity is considered benificial for geothermal plants as it cracks the rock). Injecting water might conceivably influence siesmic activity but the effect might be benificial rather than harmful. Assume that earthquakes induced by geothermal activity are due to lubrication of seismic plates and that the energy comes from the motion of the seismic plates not from the steam itself. If we imagine the steam/water lubricating the plates so they can slide freely, the result could be more frequent but less severe earthquakes - which is exactly what you want. Reduce the stored energy in the system and you reduce the potential for catastrophic damage. In the short term, you might stimulate the early release of the "big one" - though that earthquake is inevitable and the severity would be lessened slightly by premature release. Whitis 27 August 2005

I did some searching, and, as far as I can tell, the earthquakes are more of a concern with Enhanced Geothermal Systems, because they involve drilling deeper holes in the earth than the other types of plants, sometimes in areas that are not as earthquake-prone as areas that are ideal for other types of geothermal plants. and they also involve injecting water into the earth that wasn't there in the first place. I haven't found anything that says specifically that drilling wells into geothermal reservoirs causes earthquakes, and anyway, as you said, such areas have frequent earthquakes anyway.

I will try to edit the article accordingly. - Tea and crumpets 18:30, 11 September 2007 (UTC)

There still is not any mention of earthquakes in the disadantages section. The problem with earthquakes has to do with the amount of water pumped underground (or so says the Discovery Channel). I believe this is relevent with the new geothermal plants in nevada and the quakes in Reno (Discovery has yet to back me up on that one). The whole planet is prone to earthquakes, the importance to the article is that there is a measureable difference when they build a new plant or run heavy loads. Any adverse effect should be included in the text. Thanks. LD 5/20/08 —Preceding unsigned comment added by 12.104.204.212 (talk) 22:07, 20 May 2008 (UTC)

Still needed, as well as subsidence, as of April 2009.--Yannick (talk) 16:50, 10 April 2009 (UTC)

Geothermic Energy - Should there be a total separate page for it

From: [2] A new renewable energy technology could truly revolutionize the way energy is produced around the world for a fraction of the cost of what we all pay for electricity now. There are zero emissions, zero heat loss to atmosphere, and this energy can last indefinitely into the future with no damage to local or larger ecosystems. It is called "GEOthermic Energy" (as opposed to Geothermal) and it uses the deep crust (lithosphere) heat. As far as I understand it refers to totally different approach of obtaining energy ... YordanGeorgiev (talk) 14:44, 11 January 2009 (UTC)

The project as described in the reference is daft in two ways. Firstly, the technology to produce a hole twelve miles deep is unclear and sounds unlikely (a mining engineer might have stronger words) and secondly, even if the hole is made, the thermal conductivity of rock is low, and the heat content not all that great, so extracting large amounts of energy (2,000 megawatts for years on end?) means contact with a vast volume of rock. This is why proponents of ordinary geothermal systems talk about shattering or fracturing the rock at depth so that the heat-absorbing fluid can contact large areas. In natural geothermal systems, the rock is already fractured and fissured (allowing water circulation) due to volcanic eruptions. And just to be petty, hoisting the rock out of a ten-feet diameter hole from twelve miles down takes rather a lot of energy. NickyMcLean (talk) 20:13, 11 January 2009 (UTC)

It doesn't matter if the idea is feasible or not; that's not up to us to judge. The issue is Notability. We need to find significant coverage of the idea in reliable sources before we can include it.--Yannick (talk) 16:50, 10 April 2009 (UTC)

This article needs work

The article mainly contains statistics and does not include very much simply-explained, basic information for the casual reader. The sections aren't arranged very nicely, and it might benefit from some sort of map or diagram. A glance at the layout of the Hydroelectricity article makes me think we should arrange this article in a similar fashion. If anyone wants to assist me in doing this, feel free to do so. --Tea and crumpets 16:48, 23 August 2007 (UTC)

Okay, here's what I think is a better outline for this article:

1. Electricity Generation (How geothermal heat is used to generate electricity)
2. Advantages
3. Disadvantages
4. Comparison with other methods of power generation
5. Potential (including map of geothermal “hot spots”)
6. Power plants (including table listing power plants)
7. History of development
8. (any other interesting information)
9. See also
10. References
11. External links

Got any feedback? --Tea and crumpets 22:11, 24 August 2007 (UTC)

I rearranged the page, but it still needs work. No one else seems to care much about this article, so I guess I'm taking the helm. --Tea and crumpets 20:51, 30 August 2007 (UTC)

Most of the article seems to be about near surface geothermal systems, but the 'Potential' section is mostly about hot dry rock geothermal energy. Perhaps we could reorganise by technology or by the temperate of the source they exploit. Rod57 (talk) 02:08, 1 September 2008 (UTC)

Is there a link that someone can post here as to why we are not doing this everywhere and all of the time. I am so confused.

I've tried to clean up a lot of this confusion with a major rewrite. See what you think.--Yannick (talk) 16:50, 10 April 2009 (UTC)

Dry Steam

What the heck is dry steam?? This needs to be explained in the article. —Preceding unsigned comment added by Shniken1 (talk • contribs) 12:13, 25 November 2007 (UTC)

Hmm. I didn't know what it was, either. I just figured it meant they used steam as opposed to water. I looked it up, and I was only partially right. I added the explanation to the article. The source I found it at explains it a little more thoroughly. -Tea and crumpets ^{(t c)} 05:57, 2 January 2008 (UTC)

Dry steam is single phase steam without liquid droplets. Wet stem is a mixture of steam and liquid water. —Preceding unsigned comment added by Jochum (talk • contribs) 14:09, 15 February 2009 (UTC)

what r the 3 types of geothermal energy

Yes if you know the 3 types of geothermal enery u r so lucky because iv been looking and cant find anything so if u know please i need your help.... thanks —Preceding unsigned comment added by 63.215.28.181 (talk) 00:51, 20 February 2008 (UTC)

Advertising?

One of the sentences in the article seemed a little odd to me for some reason:

Since the activities of one geothermal plant affects those nearby, the consolidation plant ownership at The Geysers has been beneficial because the plants operate cooperatively instead of in their own short-term interest.

At the least, it seems like it ought to be either supported or reworded, as its current form doesn't seem to add much to the article and appears very biased in favor of the company owning the majority of the plants. For now, I've put a fact tag on it, but I'm not really sure what, if anything, ought to be done with that text.Ricree101 (talk) 07:03, 30 March 2008 (UTC)

Passage removed as of April 2009. (Not by me.)--Yannick (talk) 16:50, 10 April 2009 (UTC)

disadvantages

The following sentence from the article is not logical; the previous sentence refers to mercury, arsenic, antimony, etc, while the second half of this sentence refers to carbon emissions. These are not the same.

"However, geothermal plants can be built with emissions-controlling systems that can inject these substances back into the earth, thereby reducing carbon emissions to less than 0.1% of those from fossil fuel power plants."

These ideas need to be separated for clarity. Ngoshn (talk) 18:59, 21 July 2008 (UTC)

Well, whoever supplied the "0.1% of fossil fuel" is correct in saying that all emissions can be re-injected, because obviously, they can. Operators of actual plants do not make such comprehensive boasts. At Wairakei, only some of the waster water is re-injected, and none of the "non-condensing" gases are. Etc. It is not even clear that the comparison is with a fossil fuel plant of equivalent electrical production. Rather loose, then. NickyMcLean (talk) 21:37, 21 July 2008 (UTC)

There is a note saying "citation needed" at the statement that renewability is sometimes questioned. This paper Rybach et. al, 2002 discusses rates of heat recharge and how long it can take some installations to recover after heat extraction. It does not make a direct statement asserting renewability or otherwise, but does bear on the question, so it may be worth including instead of "citation needed." Quixote9 (talk) 23:38, 1 February 2009 (UTC)

The article concerns itself with shallow boreholes or near-surface heat reservoirs and is not in the scale of a 50+ megawatt power station. It defines "renewability" as being capable of operating at undiminished output for at least a century or more, because the rate of heat extraction/injection does not strain the capacity of the interacting volume. All fair enough. But it does not attend to large geothermal systems where groundwater is circulating through a large volume (miles in extent) and some is extracted and possibly pumped back, with putative replenishment of heat at some unknown rate from the vast heat source at greater depth. These notions strike me as obvious given the generalised model of the earth's crust, but someone wants a citation of the obvious, and I have yet to chance across such a statement of the obvious, though quantitative figures for an actual example location would be good. NickyMcLean (talk) 20:29, 2 February 2009 (UTC)

"Geothermal and biomass are the only two renewable resources which must be carefully managed in order to avoid local depletion." I know this is sited but should the word "only" really be in here? I would think that stating these two forms of renewable energy need to me monitored is enough. —Preceding unsigned comment added by Thestalkingwolf (talk • contribs) 15:19, 11 March 2009 (UTC)

The latest rewrite should provide a more neutral point of view, although this is a complicated topic that could deserve its own article.--Yannick (talk) 16:50, 10 April 2009 (UTC)

light bulbs

This article states that four light bulbs were originally powered by the Italian geothermal project in 1904. But another Wikipedia article focusing specifically on the region states there were originally five light bulbs. Anyone know which it is? [[3]]

Depends on the source used. Some say 4,[4] some say 5.[5][6][7]--Yannick (talk) 00:31, 14 April 2009 (UTC)

Corrosion

The corrosion of the equipment is caused the minerals and salts that is laced with the hot spring water. A leading statement into the disadvantage section is to say that geothermal pratices may not always be truly sustainable. (Jcoleman.39 (talk) 00:00, 6 November 2008 (UTC))

Jay Withgott and Scott Brennan. Essential Environment (The Science Behind the Stories). Copyright 2007. Pages 344-345.

Equipment breakdown is not considered in evaluations of sustainability. If it were, then the word would be meaningless, since everything always breaks down eventually.--Yannick (talk) 16:50, 10 April 2009 (UTC)

(edit semi-protected)

The last sentence under the "Potential" subheading, has the word Favorable spelled wrong.

Austinclark (talk) 15:54, 19 November 2008 (UTC)

---

Adding Links:

Can someone add our link to the External Links. We are Geothermal Resources Council located in Sacramento, CA. Our website is www.geothermal.org we would appreciate it if our website get added to your links. We have valuable information and upcoming conferences that are related geothermal power and energy. Thank You.GRCLib (talk) 17:43, 16 January 2009 (UTC)

Thanks for the suggestion, but Wikipedia's purpose is not to include a comprehensive list of external links related to each topic. You may be looking for the Open Directory Project.--Yannick (talk) 16:50, 10 April 2009 (UTC)

Electric vs heat plants and Denmark..

Shouldn't it be better specified whenever its just heating plants or electric power plants for certain countries? And maybe add/change/correct the part about Denmark? Denmark has 2 currently active geothermal plants, and two more planned to be built this year (2009). These are all exclusively for heating homes, not for producing electricity. Additionally they are not self powered and require external power to the pumps, meaning they need electricity elsewhere (primary powered by coal). (90.185.57.189 (talk) 03:16, 25 January 2009 (UTC))

Comment moved to Talk:Geothermal power in Denmark--Yannick (talk) 16:50, 10 April 2009 (UTC)

emissions free ?

with the geothermal steam we get gases which could be classified as emission. I would rather talk about low emission than emission free. —Preceding unsigned comment added by Jochum (talk • contribs) 14:39, 15 February 2009 (UTC)

Agreed and corrected.--Yannick (talk) 16:50, 10 April 2009 (UTC)

Geothermal energy is not limited to the edges of tectonic plates.

Geothermal energy is not limited to the edges of tectonic plates.

A lot of the heat pumps used for space heating uses heat out of the ground, and could be used widely. The hot rocks in Australia are not near to an edge. —Preceding unsigned comment added by Jochum (talk • contribs) 14:46, 15 February 2009 (UTC)

It's hard to talk about both electric production and direct use in the same article without confusing people, but I believe the latest rewrite addresses your concern.--Yannick (talk) 16:50, 10 April 2009 (UTC)

Binary cycle power plant

The article tells that Binary cycle power plant are the most used in geothermal for eletricity.Well, this site: http://www1.eere.energy.gov/geothermal/powerplants.html claims that Flash steam plants are the most used type of geothermal power generation plants, in operation today.Agre22 (talk) 23:45, 15 March 2009 (UTC)agre22

Fixed. Binary are the most common for new construction, but flash are still the most common in existence.--Yannick (talk) 16:50, 10 April 2009 (UTC)

Cool down the earth

Is anyone know whether use of such energy can eventually cool down the earth and whether the earth will become inhabitable ? Photnart (talk) 21:52, 24 March 2009 (UTC).

Long before that happened, geothermal stations would be abandoned for not producing any net power.

—WWoods (talk) 06:22, 8 April 2009 (UTC)

And long before that, the sun will burn out and we will have colonized other star systems. There are 10³¹ Joules of heat inside the earth, or ten billion times more than the annual global energy consumption, which is a thousand times more than the annual geothermal energy use.--Yannick (talk) 22:19, 8 April 2009 (UTC)

history of development update

Currently the Geysers are owned and operated by 4 companies. In addition to NCPA (Northern California Power Agency) and Calpine there is Bottlerock Power (with 1 power plant) and Western GeoPower (with several wells and plans for a power plant). I am currently working in the geysers geothermal field, but I don't have a registered account at wikipedia and can't edit the geothermal power page. —Preceding unsigned comment added by 173.16.183.175 (talk) 22:00, 27 March 2009 (UTC)

Thanks! Article updated.--Yannick (talk) 16:50, 10 April 2009 (UTC)

Good source to incorporate and cite

I just found a technical paper that gives a really wonderful overview of this whole topic with lots of numbers about current global status: [8] I don't have time to deal with it right away, but there's a lot of useful information here that could be incorporated into this article. So if anyone is looking for something to do... --Yannick (talk) 02:28, 6 April 2009 (UTC)

I've incorporated some of the key statistics, but there's still lots more information that could be mined out of this one.--Yannick (talk) 16:50, 10 April 2009 (UTC)

how many people use it —Preceding unsigned comment added by 199.185.67.176 (talk) 15:57, 10 June 2009 (UTC)

{{editsemiprotected}} Replace horrendously large OR template at top with {{Renewable energy sources}} 199.125.109.81 (talk) 13:20, 19 July 2009 (UTC)

Rate of Global Heat Flow

The established rate of Earth's global heat loss within the geophysical community is still 44.2 terawatts, from the compilation by Pollack, H. N., S. J. Hurter, and J. R. Johnson (1993), Heat Flow from the Earth's Interior: Analysis of the Global Data Set, Rev. Geophys., 31(3), 267–280. Please change the value of "40" given here to "44.2" and cite this reference.

Thanks, Michael Wysession Professor of Geophysics Department of Earth and Planetary Sciences Washington University St. Louis, MO 63130