CHEAP AND RENEWABLE?: A new analysis shows that geothermal power plants might produce electricity more cheaply than burning coal.
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Although the environmental benefits of burning less fossil fuel by using renewable sources of energy—such as geothermal, hydropower, solar and wind—are clear, there's been a serious roadblock in their adoption: cost per kilowatt-hour.
That barrier may be opening, however—at least for one of these sources. Two recent reports, among others, suggest that geothermal may actually be cheaper than every other source, including coal. Geothermal power plants work by pumping hot water from deep beneath Earth's surface, which can either be used to turn steam turbines directly or to heat a second, more volatile liquid such as isobutane (which then turns a steam turbine).
Combine a new U.S. president pushing a stimulus package that includes $28 billion in direct subsidies for renewable energy with another $13 billion for research and development, and the picture for renewable energy—geothermal power among the options—is brightening. The newest report, from international investment bank Credit Suisse, says geothermal power costs 3.6 cents per kilowatt-hour, versus 5.5 cents per kilowatt-hour for coal.
That does not mean companies are rushing to build geothermal plants: There are a number of assumptions in the geothermal figure. First, there are the tax incentives, which save about 1.9 cents per kilowatt-hour. Those won't necessarily last forever, however—although the stimulus bill extended them through 2013.
Second, the Credit Suisse analysis relied on what is called the "levelized [sic] cost of energy," or the total cost to produce a given unit of energy. Embedded within this figure is an assumption that the money to build a new geothermal plant is available at reasonable interest rates—on the order of 8 percent.
In today's economic climate, that just isn't the case. "In general, there is financing out there for geothermal, but it's difficult to get and it's expensive," Geothermal Energy Association director Karl Gawell told ScientificAmerican.com recently. "You have to have a really premium project to get even credit card interest rates."
That means very high up-front costs. As a result, companies are more likely to spend money on things with lower front-end costs, like natural gas–powered plants, which are cheap to build but relatively expensive to operate because of the cost of the fuel needed to run them.
"Natural gas is popular for this reason," says Kevin Kitz, an engineer at Boise, Idaho–based U.S. Geothermal, Inc, which owns and operates three geothermal sites. "It has a low capital cost, and even if you project cost of natural gas to be high in future, if you use a high [interest rate in your model] that doesn't matter very much."
Natural gas, which came in at 5.2 cents per kilowatt-hour in the analysis, is also popular because it can be deployed anywhere, whereas only 13 U.S. states have identified geothermal resources. Although this limits the scalability of geothermal power, a 2008 survey by the U.S. Geological Survey estimates that the U.S. possesses 40,000 megawatts of geothermal energy that could be exploited using today's technology. (For comparison, the average coal-fired power plant in the U.S. has a capacity of more than 500 MW.)
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Add CommentWith President Obama's stimulus package, there is no excuse not to build geothermal power plants in every state. What you save in the cost of health and the environment, in a short time, the geothermal plant will pay for itself. West Virginia wants to spend 3 billion dollars to build one coal to liquid plant that will increase pollution by nearly 400%. West Virginia could use that 3 billion to build two geothermal power plants with 20 turbines in each plant and generate enough power to supply 140 million homes and businesses. West Virginia has been blinded by coal dust and cannot see the profit in using that 3 billion to build geothermal power plants. West Virginia can benefit themselves by getting a different governor that has not been bought off by big coal.
Reply | Report Abuse | Link to thisThe discussion about how to progress with the world's future energy sources is imho tainted, and information is presented in an untrue manner.
Reply | Report Abuse | Link to thisFighting the figures you presented is futile, but I believe they only present part of the picture.
There is imho no possible way to explain that nuclear energy can be cheaper than CSP solar power.
Once you have a plant up and running, the energy carrier is FREE. The technology is not overwhelmingly complex and easy to standardize.
The technology has been tested and has proven to function satsifactorily. There are examples in Spain and USA that show it works.
Start large-scale use of CSP's and I cannot see why prices shouldn't drop considerably in comparison to the figures you presented in the chart.
(I doubt that these figures can be right, if you scale in the absolutely mind-blasting investments made into nuclear research!)
A problem mentioned is the need for long transmission lines. Modern HVDC run at a 3% loss over 1000 km. Sure, it's an investment, and if we only could start thinking longterm, we would make them even more expensive by putting them 10 feet underground, making them terror-proof. If they can stay there for 50-100 years, it will pay off.
Geothermal energy: San Fransisco has been running on geothermal energy since the early 60's. Iceland uses plenty of it. Other places use it with great succes. The technology has been tested and has proven to be both reliable, clean and safe. The entire western part of the US has geothermal potential, and I believe the USGS has a good overview where to drill. The Yellowstone hotspot has in itself the potential to supply the entire world with energy for hundreds of thousands of years.
I would like to propose mankind starts to think longterm. We NEED to cut the CO2. Not to pleasure the likes of Mr. Gore or the IPCC. But think purely scientific: we are emitting insane amounts of a biologically active gass in our atmosphere. That will have biological consequences. I don't want to think about how bad that can be. It's nourishment not only to plants, but also to bacteria and virusses.
Nuclear energy is not the cure, however. It is a technology that involves a huge and toxic infrastructure. If we want to set an example for the rest of the world, making it a safer place, we need to look into a different direction. Solar energy alone can supply the entire world with sufficient energy for as long as earth is habitable. Geothermal is a good second. I do not see any sensible longterm alternative.
That table is in $/MW-h, right? ($10/MW-h = 1�/kW-h.)
Reply | Report Abuse | Link to thisAgree, I think Geothermal is a great idea. But we don't here much talk about it in the media. And I also agree with fellow blogger who said, "Nuclear is Not the cure". In fact, I don't like nuclear at all. Amory Lovins-RMI.Org testified that nuclear was too costly, and incouraged solar, wind, and I don't remember if he supported Geothermal as well.
Reply | Report Abuse | Link to thisBut WHY not promote and foster solar and low profile wind turbines for buildings and homes???????????? If people were more self sufficient, we wouldn't have to build big expensive power plants. Another suggestion; what about incorporating neighborhood solar and wind power stations for individual neighborhoods, or communities coupled with homes who are also able to generate their own individual power through wind and/or solar?? Why doesn't anybody talk about that???!!!
Any thoughts??
Ok Ronwer; you mentioned transmission lines as a problem. My idea sounds even better..... transmission lines would not be a problem.
Reply | Report Abuse | Link to thisJamesDavis; And remember, people are always afraid of change.
Reply | Report Abuse | Link to thisThe people of WV just need to know that geothermal can work for them. And will geothermal provide jobs. They are a state with an economy dependent of coal. Get a new governor, one with vision, and a plan to build a more diversified state economy.
I agree entirely. But it wasn't me who considered investing a $60 billion a problem. See SciAm no. 5, 2009 page 32.
Reply | Report Abuse | Link to thisConsidering current budget deficits, it's peanuts. Considering the urgent need for new jobs, it seems to me a smart move. It will create plenty of relatively low-tech jobs for which many workers should qualify, with or without a short course.
Long before the US has a new generation nuclear plants up and running, you could have plenty of megawats solar and geothemal energy installed.
Purr09
Reply | Report Abuse | Link to thisThere are many problems with large scale use of home energy systems if you don't have large power plants and/or a large scale reliable energy system to back them up. These problems are:
1. Energy storage - how do you effectively store the energy in your house, or neighborhood for the overcast, windless day.
2. System Frequency - the large energy systems regulate their power output to 60 Hz plus or minus 0.2 Hz by adding dropping power generation as required. This keeps all your clocks, motors, etc. etc. running at the speed required. This is very hard to do when you only have solar/wind on a small scale, which is not connected to a large grid.
3. Reserve Power - This is required when everyone comes home at 5 PM, and turns on their oven/TV/etc. If you are the only person on the grid, it's your problem to install enough solar panels/battery storage/etc. to meet these requirements. If you are one of 20 homes, you have to institute who is responsible for, and how much energy margin is required.
4. Cost - The cost of solar is still prohibitive (as shown by the above article), but could be used on a smaller scale.
5. Efficiency - In general, efficiencies at large plants are higher than efficiencies on individual homes or groups of homes. Solar (photoelectric) is only 15 -20% efficient; wind is only 50% efficient compared with hydroelectric power plants at 85% efficiency (These were not included in the above study!?) and fossil fueled plants at 40 - 50% efficiency. Wind parks require the same transmission lines that large power plants do; so the main benefit is they are pollution free.
In summary, I'm highly in favor of more geothermal, wind, solar, hydro and any other zero emission generation system; and home generation can be a minor part of that scheme. However, it will never be a major part because frequency regulation/reserve power/energy storage can only be effectively instituted on a larger scale.
Not covered in this article is the geothermal mechanization termed EGS - Extended Geothermal Systems which do not rely on finding "hot water" but use hot rocks and pump water in to be heated. The beauty of this technology is that it has the capcity to become the backbone of our electric grid if its economics can be driven to be viable.
Reply | Report Abuse | Link to thisComments on this would be appreciated.
David, these issues can all be addressed with relative ease. Especially if you're using a combination of wind and solar.
Reply | Report Abuse | Link to this1. Battery systems may be expensive, but they work. Electricity needs during the night are fairly low anyhow. During the day excess energy is charging deep cycle batteries, during the night the home is powered by wind and the batteries. If the batteries are full, the energy is pumped into the grid. The grid still exists to help distribute power, especially if someone has an equipment failure.
2. The battery system solves this. Extra power needed can be pulled from the batteries, surplus power is stored in the batteries. So long as you produce 10% more energy from your solar/wind systems than the average need you should be fine. Being connected to a peer-powered grid further alleviates this.
3. Batteries again.
4. If homes were built to the maximum of efficiency, they wouldn't need all that energy. It is possible to build a home for about the same price as building a standard home and have it use only 80% less energy than a standard home. This means that the solar/wind system could be 80% smaller than the average system and still provide 100% of the energy needs for the home. If people would just build homes CORRECTLY, it would solve a ton of problems... especially when you consider that heating/cooling accounts for 40% of the US energy consumption.
5. With more efficient homes, this isn't as big of a deal. But you're right, the efficiencies do need to improve. They will only do so if they become mass produced, take off, and are more widely used. Once the technology gets out there and sees widespread use, they will be able to spend more on R&D. By the time your system wears out, in 25-50 years, you will be able to buy a new system that is much more efficient for a fraction of the cost.
I don't like the idea of centralized power at all. While it would be great to use to supplement a distributed system, I think that centralized power is too much of a security risk. If less than five power plants where knocked out in the US, the entire US would experience rolling blackouts and a complete loss of power very quickly. If the system was distributed, and every home produced their own power, then it wouldn't matter one bit if one house suddenly lost power.
Also, because of the amount of power lost in transmission, it makes more sense to generate power as close to the point of use as possible. I would imagine that the efficiencies gained by a large power plant are lost in transmission resulting in no gain.
I disagree with your point 4).
Reply | Report Abuse | Link to thisStudies in Europe have shown that CSP solar energy is cheaper than fossil fuels. Of course, you need large scale application! This study was done in connection with German plans to build a CSP plant in Algeria. Additionally a cable between Algeria and Aachen in Germany is constructed.
That is why I called this study "tainted" in my first comment. I refuse to accept these figures.
The beauty of geothermal energy is that it is on demand. But so are modern CSP plants. The energy is stored in molten salt in large underground containers. That way you can also generate power during the night.
But for many areas in the USA local solutions would be preferable. Many western states and southern states have plenty of sun. Just keep yourself connected to the grid, but install PV panels on your roof. It seems that PV is on the verge of becoming really mature with new technologies able to use a higher percentage of the sunlight. But storage at a small scale seems indeed to be futile.
In the US you would need to allocate a few desert regions for large scale production of solar energy. Sure, it would require a major effort from both the workers doing the job, and politicians planning it all, but I would think you could get rid of all fossil fuels and nuclear energy within 50 years. But then your politicians must stop acting like an extension piece of Big Business. It's OUR world too. If I had the choice what I leave behind for future generations, then it is definitely NOT a society with lots of toxic, radioactive infrastructure and waste products that need taking care off for many dozens to several thousands of years. And it wouldn't be a world where excessive CO2 emissions cause both the climate AND the evolution to go haywire. Whether or not there are creationists among SciAm readers, the increase in CO2 levels will still per definition have the potential to alter the course of evolution. What superficially might seem beneficial -more vegetation- can actually become the single greatest threath to humanity. Because also bacteria, virusses, insects etc. will thrive, mutating faster, spreading faster, potentially causing pandemics to which we have no defense.
I see no no sense in anything else than a combination of geothermal and solar energy. It is sustainable and will last as long as this planet is habitable.
For crying out loud. Tax subsidies RAISE the cost, they don't lower it. Do you think the tax money comes from pixie dust?
Reply | Report Abuse | Link to thisLearn some basic economics, SA
Yes, you are absolutely right to point this out.
Reply | Report Abuse | Link to thisEGS is a promising technology. There has already been done a lot of research and as far as I know from publications available through the internet, the question is no longer whether or not it works. It does.
Just for fun I once calculated how much energy is stored in the Yellowstone hotspot. I lost the figures, but if you search the usenet groups of 6-8 years ago, you might find it back.
The conclusion was that Yellowstone alone could produce more energy the world needs yearly for many hundreds of thousands of years. Sure, not all that energy is harnassable.
But it is clear you could generate sufficient power to run most of the US on it. Let's be more conservative, let's say 25%. An additional 25% comes from other geothermal sources, and the remaining 50% comes from solar power.
You wouldn't need to think about your energy supply for the foreseeable future.
Build much more solar plants than strictly necessary for power production, and start large scale desalination of ocean water for the purpose of irrigation.
I cannot see why anyone is talking about an energy crisis when both the necessary resources and technology are available. You need to get serious about this.
Make the US independant from fossil fuels, abolish nuclear energy, and show the world a new direction. To speak with your current leader: "Can we do it? Yes we can!"
I believe Nathaniel's conclusions on our ultimate grid being driven by central supplies is correct. The issues scales of economy and storage are key.
Reply | Report Abuse | Link to thisThe question of the role of solar versus geothermal, I find to be an interesting one; geothermal in its EGS (extended geothermal system) implementation is a fascinating possibility of have a generally widely distributed resource used - probably in units of hundreds of mw generation as a real possibility - with the mix determned by economics over the next few decades.
Can anyone find the report by Credit Suisse where the LCOE table is taken from? It would be interesting to see how they came up with those numbers.
Reply | Report Abuse | Link to thisThe U.S. Coal industry (Old King Coal) is not going to sit down and let any renewable energy sources take the lead. Please, please prove me wrong!
Reply | Report Abuse | Link to thisI don't think that your second sentence is unambigious. You say: "The issues scales of economy and storage are key."
Reply | Report Abuse | Link to thisI am just a simple Dutchman, but don't tell me this is a correct sentence.
Regarding storage.
Geothermal energy is on demand. You can go from 0 to 100% in the shortest possible time.
Solar energy has evolved, and especially the CSP echnology has become mature. Storage of heath in huge containers with molten salt has proven to be a reasonable way of storing energy. But you need large-scale application of this technology to make it profitable.
The amount of energy available to the US with regards to renewables is so overwhelming, that it's a miracle you have avoided using it on a much larger scale for decades.
Good ol' San Fran has been runing on geothermal since the early 60's.
The total potential of the superficial deposits in the US alone, is enough for massive amounts of energy. And that means, sustainable for many centuries at a given yield per field. Which is a desirable norm anyway. We must harvest, not devour the source.
What the US needs is a new discussion. Open the eyes of your entire population for existing possibilities. Tell them that your natural resources will make you independant.
Anyway, the times of the fossil fuels is coming to an end.
We can continue current level of increase of use for a couple of hundreds of years, but hardly more.
The mere prospect is enough to make such fuels an unacceptable energy carrier.
We can imagine that future mankind might have use for large quantities of carbon. I believe there is a overwhelmingly good chance that future technology is predominantly based on carbon. Burning up the best deposits doens't make sense....
Drilling deeper will give you access to huge amounts of energy, enough for your entire country for many hundreds of thousands of years to come.
Imagine a energy carrier that doesn't cost you anything at all. You must only install the apparatus to harvest the energy. That is what solar and geothermal energy is about!
Initial costs may be high currently, but when such plants are up and running, they don't need much supervision. Reliability of such plants has proven to be extremely satisfactory.
The US can show the world a new way. A completely new future regarding energy production. You can be completely independant within a few decades. And thereby improve on technologies that are of great interest to the rest of the world.
Can you steer us to anyplace where there is some description of EGS work actually done - i.e., drilling and ciruclating water? And any analysis of capitial cost to drill - for this is most likely the primary driver on economics.
Reply | Report Abuse | Link to thisSome general information about solar energy:
Reply | Report Abuse | Link to thishttp://www.trec-uk.org.uk/articles/gdn_061127_ber_27_15216508.pdf
A report on EGS:
Reply | Report Abuse | Link to thishttp://geothermal.inel.gov/publications/future_of_geothermal_energy.pdf
All of the shortcomings you mention do not apply to geothermal.
Reply | Report Abuse | Link to thisNathaniel
Reply | Report Abuse | Link to thisBatteries work on small energy systems, but are not good for larger systems (over 10 MW) because they are:
1. Expensive
2. Short Life (10 to 15 years) with a limited number of recharges
3. Inefficient. Approx. 50% efficiency (chemical to electrical)
4. Create disposable/environmental waste problems when implemented on a large scale.
5. Temperature sensitive to obtain your maximum output/recharge values.
6. High maintenance costs
I was involved in the installation of numerous battery systems at power plants (battery sizes were from 100 AHr to 2000 AHr); and know there are many problems with battery storage systems. However, as an emergency back-up to critical systems, they are the only way to go for small scale, dependendable power.
I also have technical literature on the 40 MW NiCad (3,400 Nickel Cadmium batteries) system commissioned in Alaska in 2003 to serve over 90,000 people. This was required because the municipal utility was on an electrical island with only one outside power connection. They would have preferred a small pumped storage plant, but it was not possible. There are numerous problems (maintenance costs, anticipated replacement costs, etc.) becoming evident in this system that were not so evident initially.
And finally, one last plug for hydroelectric pumped storage as an energy storage system. It has the following benefits:
1. Inexpensive (approx. $2000/kw vs battery systems $3,000/kw plus)
2. Long life (75 to 100 years vs a battery systems 10 to 15 years)
3. High efficiency (over 72% round trip efficiency)
4. Low maintenance costs.
5. Able to store 10 MW to 2000 MW of energy
6. Not temperature sensitive. Functions in any environment.
7. No toxic elements to dispose of at the end of life.
In summary, battery energy storage systems have their place; but it is not in large energy storage. And, if you're talking individual house battery systems, I would ask you to consider the quantities involved, and environmental disposal questions for a 1 million households.
Nathaniel
Reply | Report Abuse | Link to thisYour assumption that the efficiencies gained by large power plants are lost in transmission is wrong. Standard transmission line are designed to have losses not exceed 10%. Hydroelectric power plant efficiencies are more than 85%, fossil fueled plants in the 40 to 50% range. Consequently, a 10% transmission loss would still make your hydro plant 75% efficient over all compared to a solar/wind generator at your house that is 20% and 50% efficient respectively.
With wind power being 50% efficient, and renewable; it is a possibility. Solar is still too inefficient and costly.
Regarding energy storage.
Reply | Report Abuse | Link to this1) Check following link:
http://www.shpegs.org/
2) Another thought is to use extra capacity during the summer to fill up large reservoirs with water, which can be tapped off during the night and winter.
The article speaks of the problems of contaminants that are present in the subsurface water that is used for geothermal energy. Furthermore, there is difficulty to locate appropriate sites. My question is why not use technology from the oilfield to do the following?...
Reply | Report Abuse | Link to this1) Drill two boreholes to an appropriate depth, using existing directional drilling technology to join those boreholes at the bottom. Some more horizontal drilling at the bottom would increase the desired heat exposure.
2) Run steel casing in both boreholes to seal them. These two casing strings will have an opening between them at the bottom (perhaps some minor development to implement that reliably).
3) Pump clean water down one well, and the resulting hot water/steam comes out the other well. After passing through the surface generator steam turbines, the condensed water goes back into the downward well. The difference in pressure (steam lighter than water) makes the water movement self-sustaining.
Because it is a sealed system, contaminants cease to be a problem. Furthermore, subsurface water is no longer needed. These two benefits greatly expand the potential sites for geothermal. The drawbacks that I see are an increased up-front cost for the dual wells and casing, and also a need for deeper drilling, such that the water has better exposure to the high temperatures.
This seems to me an obvious solution, so I guess it must be already used, but I am quite surprised not to see mention of it in this article or others. Is it not so obvious as it seems?
ronwer224
Reply | Report Abuse | Link to thisFilling up reservoirs at night, and using them to generate electricity during the day is exactly what "pumped storage hydro" plants do. It uses the cheap electricity at night, and generates power for the 5PM after work crowd, when electricity is the most expensive. However, you can use any excess generation to pump the water (not just at night), e.g. if you have the wind blowing at 40 MPH for 3 days straight.
Pumped storage is a tried and proven technology, with a high efficiency, and zero emissions. There are over 400 pumped storage facilities operating around the world; and at least 20 in the U.S.
The discussion on pumped storage does not treat the issue of capacity. I agree that pumped storage is a valuable tool; but can you find enough resevoirs to back up a grid of intermittent resources supplying 20%, 30%, 50% or more our ennergy?
Reply | Report Abuse | Link to thisSol Shapiro
Reply | Report Abuse | Link to thisI agree it does not treat the issue of capacity. Pumped storage is for energy storage. It will store the intermittent energy supply furnished by wind and solar to make them a more valuable/reliable renewable energy source because it can supply the energy when needed. It can also store the energy from geothermal plants so that you can run them at 100% of rated capacity on a full time basis; not on an as needed basis. (People don't need the energy at 2 AM in the morning). This allows you to maximize your energy output from a renewable energy source rather than building new coal plants to supply the additional load required during the daytime.
There are many locations for pumped storage plants because they only require an upper and lower reservoir, with only a 5 to 10% water input to account for evaporation, usually from a local creek or small stream. More than 90% of the water is recycled between the reservoirs on a continual basis.
Remember, they have a 72% round trip efficiency, zero emissions, and utilize 90 to 95% of the same water in a closed system.
The order of the day must be: "Throw everything at it!" Generate the energy using: geothermal; all kinds of solar; ecological construction and energy-saving using education campaigns and compulsory but subsidized retrofitting; wave, tidal and lake and river power; wind on an industrial and local scale -- both on land and at sea; and whatever other renewable sources I've forgotten here. Then transmit using the High Voltage Direct Current (HVDC) technology now under rapid development and undergoing relatively large-scale live trials in Sweden (ABB/ASEA). TRANSMISSION is the keep to all of this. A bit more costly to install but dirt cheap to run by comparison with LVAC, and orders of magnitude better in terms of minimal-loss efficiency, distances covered, and value for invested penny. Using this technology the world's huge energy reserves (Iceland's geothermal wealth -- the Earth's magma, anyone??; the Sahara's solar riches; the Gulf Stream) to name but a few examples -- can and will be harvested and transported to where it's needed best -- industrial and urban concentrations. This won't take long. When the first GigaWatt installations are working, we'll boggle -- just as we've been boggling for decades at the constantly expanding progress in computing power. So all our prognoses should reckon with logarithmic plus acceleration in renewables availability, efficiency and falling prices. If you compare the hidden costs in terms of lost lives and quality of life destroyed by coal, over centuries now, and the deliberately hidden costs and dangers of nuclear research, construction, security and decommissioning/final storage, it is easy to see that the proponents of these power providers are lying through their teeth about "necessity", "realism" and "cost benefits". QED
Reply | Report Abuse | Link to thisSorry but I did not see an answer on the issue of capacity. U.S. generating capacity is now about one million megawatts and about 4E12 kwh per year. On a daily basis, say you need 20% of the days use which would mean storing about 2e9 kwh of energy. How much volume of watger at what head would this entail? If my numbers are too high - has anyone really looked at the reality of sizing pumped storage for U.S. energy use?
Reply | Report Abuse | Link to thisSol Shapiro
Reply | Report Abuse | Link to thisThe most recent (I'm retired) statistics I have on pumped storage (WaterPower 1995, Proceedings of the International Conference on Hydropower, Vol 2, "Hydro Pumped Storage) stated it was 2.7% of the U.S. grid. If your statement that the U.S., at present, has 1 million megawatts, this would ballpark pumped storage at the 20,000 to 30,000 MW range, which seems reasonable. I know since 1985, there has been over 6,000 MW of pumped storage installed in the U.S., and that preliminary permits or licenses have recently been filed for 15 pumped storage projects totaling over 10,000 MW more(Reference Hydro Review magazine, Editorial, June 2008)
I believe these are fairly adequate numbers for energy storage when one considers that wind generation only totals 21,000 MW (9% of the total renewable energy produced)as of 2007, and Geothermal power, at present, only totals 4% of the renewable energy produced,(or approx. 9,000 MW. (Reference IEEE Power & Energy magazine, Nov/Dec 2008)
However, to play on an even field, let me rephrase the question to you. How much battery energy storage is there in the U.S. at present? I'm sure it is no where near 20,000 MW. And how many preliminary permits/licenses are there for geothermal plants? I am sure the hydro pumped storage facilities can be installed at a much faster rate than geothermal plants can be installed because it is a proven technology (they know the time frames to build and commission).
@David M. Clement
Reply | Report Abuse | Link to thisWhat makes you believe geothermal is not a proven technology?
San Fransisco has been running on geothermal energy since the early 60's. With good results.
Iceland, Phillipines, Italy etc. etc. Many countries have working plants that perform very satisfactorily.
There seems to be no reason to doubt that geothermal is a viable technology. It's energy on demand, so you won't need batteries.
But I agree, pumped storage makes sense the day you start installing huge numbers of CSP-plants. However, you would need a significant number of Grand Coulee's to be able to garantuee enough power during the night and winter.
If it turns out that environmental concerns would make it difficult, I would suggest you start negiotiating with Canada. They have enough space for a number of reservoirs.
What I fail to understand, is that a country with so many smart people hasn't started doing this 20 years ago...
I have designed, built and operated coal and geothermal plants, and find many of the conclusions in your piece just plain wrong.
Reply | Report Abuse | Link to thisThe permis is correct but there are significant mis-statements by the quoted parties. Only poorly operated steam geothermal plants have low availabilities, but in the 80% range, not 60%. Most new geothermal will be few steam and flash plants and mostly medium temperature binary cycle plants. For example, the Steamboat II and III binary plants have a 10 year average availability of 99.8% and capacity factor average of 115% --- and this is very typical of binary cycle plants (Mr. Makovich is ill-informed).
Also, I can't imagine a coal plant getting a permit in less that several years, if at all. Externality costs for coal are a large undefined risk.
Additionally, coal plants need extensive maintenance to survive, 30 years, let alone 50 years, with thermal cycles and effects of combustion causing serious metal fatigue, corrosion and erosion problems. Binary cycle geothermal plants are low temperature and pressure, lasting indefinitly with much less maintenance.
Please try to present an accurate account of the technologies.
Shuman Moore
775-324-3044
smoore@oskienergy.com
The problem you have isn't the generational price, its the cost to constant repairs to the overall plant and systems. Anytime you admit a substance like water to the earth you get back super mineralized steam being admitted back to a highly engineered steam turbine and process plant pipework. In other words you will plug the whole darn thing up with absorbed minerals being deposited throughout the whole plant. And this will be done quite quickly! So, you will replace the major components of the plant regularly increasing the cost of the plant maintenance and also as the plant plugs up, the overall efficiency of the plant is severely infringed on.
Reply | Report Abuse | Link to thisSo where's your savings? Only when its operating a peak efficiency because most of the time your systems are plugging up.
David Clemen,
Reply | Report Abuse | Link to thisI'm not fighting the idea of using pumped hydro storage. I'm looking for real numbers to assess capacity capabiilyt - how much volume storage, how much head is feasible; and the economics as you try to expand it.
I see the beauty of geothermal - as not requiring storage; and of solar thermal with storage as viable with backup gas when storage is consumed. So the basic question is - is anyone reading this a sufficient expert on pumped hydro to discuss capacity and enconomics and educate the rest of us?
I'm glad to see this coverage but disgusted by the tiny amonnt of support from the DOE, even with Steven Chu in charge. Billions for clean coal and only 85 million for geothermal development. My article:
Reply | Report Abuse | Link to thiswww.clrlight.org/coal.pdf
I'm glad to see this coverage but disgusted by the tiny amonnt of support from the DOE, even with Steven Chu in charge. Billions for clean coal and only 85 million for geothermal development. My article:
Reply | Report Abuse | Link to thiswww.clrlight.org/coal.pdf
Sol Shapiro
Reply | Report Abuse | Link to thisThe formula for pumped storage power is P(kw) = 9.8 x Head(meters) x Flow (cubic meters per second) x efficiency. The reservoirs are usually sized for a 10 hour storage to supply the additional energy during the day; they pump the water into the upper reservoir during the night when the energy used for pumping is less expensive. Reservoirs would have to be made larger for a longer than 10 hour storage supply, but it is more expensive. The usual reservoir sizes are between 100 acres to 1000 acres.
Some typical info from the "Davis Handbook of Applied Hydraulics", 4th edition, published by my old firm (I'm retired). "Pumped storage plants normally have operating heads between 300 and 1500 ft. Heads lower than that have excessive dimensions, resulting in high costs. Heads higher than 2500 ft result in "special equipment and materials" because of the high operating pressures. ...A 500 MW project operating under a head of 1000 ft requires an active storage of 6000 acre-ft in each reservoir to provide 10 hours of generation, or 5000 MWhrs. A higher operating head would permit the use of smaller reservoirs. A 6000 acre-ft reservoir can be provided with an average reservoir area of 100 acres, and a fluctuation of 60 ft."
For more info, you have to go to the book, or the internet. In any case, pumped storage has been around a long time, has a high efficiency, and is a self contained system that doesn't require much space. The story around the office before I retired was that there were more than 60,000 MW of good pumped storage sites in the U.S., if anyone wanted to develop them.
@tblakeslee
Reply | Report Abuse | Link to thisUnfortunately, but it shows that your country is still in the hands of lethally corrupt people. And their advisors come from the wrong stable.
Yep, I am afraid that the western world is morally bancrupt. We just don't seem to be able to listen to the voice of reason.
I liked the story. We never hear much about geothermal, but why not? It's the energy under our feet.
Reply | Report Abuse | Link to thisEnergy storage is a killer for wind and solar. How can be store 100's of MWs? Even if every home had batteries, the number of batteries needed would in the billions.
Please send us more stories on geothermal.
Reply to Less1leg 3-6-09 comment: Even the most mineralized geothermal brines can be managed with good, low cost chemical treatment, keeping O&M costs to a very reasonable amount. But the point is that most medium temperature binary cycle goethermal systems don't have a problem with mineral percipitates as they never are exposed to ambient conditions, they are maintained in a liquid state, not allowed to flash to vapor and reinjected back into the resource, not consumed. Also, most medium temperature brines are relative low TDS, some approaching drinking water quality. The typical binary cycle O&M cost for a 15 MW size facility is less than 2 cents per kW hr., obviously dependent on total plant size.
Reply | Report Abuse | Link to thisIf this discussion of energy storage by cycling water between reservoirs at different elevations is assuming that the water to be used is that flowing down our rivers, that is a really bad plan. Dams on rivers have long been recognized as major problems in the ecological sense and from the engineering issues with water losses directly into the flooded rock strata. My guess is that seepage losses are larger than evaporation losses. Water and energy usage are inextricably linked. Water shortages wordwide present as big (or bigger) a problem than energy generation. More dams are in the process of removal in this country than are being constructed. Forget about messing with river hydropower at the levels you guys are discussing.
Reply | Report Abuse | Link to thisNow, you might be able to make an argument about using this sort of technology on seawater but there would have to be a good seal in the upper reservoir to avoid polluting freshwater supplies.
Then there is tidal power. Low head but pumping cost is free.
Geodude
Reply | Report Abuse | Link to thisPumped storage does not utilize dams on rivers. Look it up in Wikipedia to educate yourself. Also, there are not more dams being demolished than constructed. Reference any issue within the last 2 years of Hydro Review magazine, or any other water power magazine; or look at "hydropower" on wikipedia.
Hydro is a renewable source of power with zero emissions. It's facilities last for 75 to 100 years; and hydro is the most efficient renewable energy source. Hydro already produces 98,000 MW, or about 6% of the total U.S. grid.
> San Francisco
Reply | Report Abuse | Link to thisnatural geysers. These aren't the same as drilling for heat, rememer!
http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2008/02/15/BU21V2S7J.DTL
Volume 38, Issue 1, March 2009, Pages 145-154
Special Issue on the Wairakei Geothermal Field, New Zealand: 50 Years Generating Electricity
Comparative analysis, nuclear to Geothermal, to Wind, to Solar, to Hydro to Tidal is folly - all will be needed, and in full force to maintain the "American Dream" lifestyle as the cheap oil era ends and reality sets in over a job-starved America that produces nothing the world doesn't already provide for itself only cheaper! The extremely arrogant position taken at the outset of this article is a preposterous position in the first place! We, North Americans, simply do not have the luxury of debate in these matters and must move quickly to fill the gaps in our dying economy with power for survival, from any source! and desperately try to survive the Asian onslaught on our lives! We are no longer competitive! Get it? We are going to die in the dark, soon! Understand? We must pay our bills, now! Realize this? Our labor is worth 85 cents and hour in China, feel choked up? We are not "Entitled" or "Chosen" people. Disappointed? We must pay, in "Yuan" equivalents for Chinese products. Surprised? They "own" us. Fear This!
Reply | Report Abuse | Link to thisComparative analysis, nuclear to Geothermal, to Wind, to Solar, to Hydro to Tidal is folly - all will be needed, and in full force to maintain the "American Dream" lifestyle as the cheap oil era ends and reality sets in over a job-starved America that produces nothing the world doesn't already provide for itself only cheaper! The extremely arrogant position taken at the outset of this article is a preposterous position in the first place! We, North Americans, simply do not have the luxury of debate in these matters and must move quickly to fill the gaps in our dying economy with power for survival, from any source! and desperately try to survive the Asian onslaught on our lives! We are no longer competitive! Get it? We are going to die in the dark, soon! Understand? We must pay our bills, now! Realize this? Our labor is worth 85 cents and hour in China, feel choked up? We are not "Entitled" or "Chosen" people. Disappointed? We must pay, in "Yuan" equivalents for Chinese products. Surprised? They "own" us. Fear This!
Reply | Report Abuse | Link to thisFiguring costs on an entropy basis makes geothermal prohibitive. The CO2 released from cooling magma, for example, is not in the price mechanism. See "Entropy not Energy is the Issue",
Reply | Report Abuse | Link to thiswww.newearthrising.org
Issue # 1.
Our National Energy Labs are managed by interconnected boards of directorates that trace back to the interests of Battelle (coal-electric, plug-in cars, CO2 dumping, , etc.). These interests can be culled out by an entropy analysis. Search for Entropy (not Energy) is the Issue (this site) for an explanation.
Reply | Report Abuse | Link to thisYes Kitz, some of us out here love you; keep at it, we do not have the mental ability or the time (groceries) to do so.
Reply | Report Abuse | Link to thisjohn m
If Geothermal power is ever to be given the respect i deserves as a potential replacement for dirty energy, a major change in paradigm as to its availability.
Reply | Report Abuse | Link to thisI used to work on oil, gas and geothermal drilling rigs.
The idea that you must have hot, wet rock formations near the surface (such as in geyser or hot-spring areas) in order to make geothermal energy economically feasible is incorrect.
If we can afford to drill holes 26,000 feet deep (many of them dry) to access oil and gas, then it would be economical to drill intersecting holes that deep (it can be done with existing technology) then pump water down one hole and get steam out of the other. Almost anywhere on Earth's surface, if you drill that deep, you hit HOT rock. In most places you don't have to go that deep.
Drilling in "hydrogeothermal areas" is exceedingly expensive, even if you don't have to go that deep. The rock in near-surface hydrogeothermal atreas is full of cracks and unstable. The wet heat and dissolved minerals destroy drilling bits, (even diamond-studded ones with titanium bearings), very quickly. Much time and cost are spent during the drilling process dealing with and compensating for the brittleness and porosity of the rock formation.
In deep, stable, dry hot-rock formations, drilling costs much less per foot of hole than in the hydro formations.
Using hydrogeothermal water or steam to run power plants also causes the operation of those plants to be very costly because of the acidic 0r caustic nature of that water and the minerals dissolved in the water or steam.
If the water is pumped into a hole for hot water or steam, the water can be filtered or demineralized before being pumped in if it needs to be, reducing the cost of running a geothermal power plant.
Unlike other clean energy options, geothermal energy is constant and consistent, and available almost anywhere. All that is required is the infrastructure, the fuel is free and inexhaustible.
Competent energy policy discussions begin with entropy. No entropy analysis; no adequate pricing; no credibility.
Reply | Report Abuse | Link to thisSince the release of CO2 is a problem for geothermal, why isnt this discharge included in the pricing table? The promoters know of this, but of course keep it from na�ve reporters. Again, only a relative entropy analysis will give meaningful cost comparisons.
Reply | Report Abuse | Link to thisF
Reply | Report Abuse | Link to thisForget all this technology stuff. What about subways in
Reply | Report Abuse | Link to thisSan Francisco, L.A. , and Mexico City, as well as the Chunnel.
Trains get about 4 times the distance per unit of fuel as to the
automobile. Live/work, bicycles, walking, and mass transit
make a difference.
Then too, I have an ice conditioner idea (actually used some
places) that you "store" electricity at night when cold temperatures, electricity available in the form of ice. Hold
it for a few hours to use for airconditioning cool. You store
electricity in the form of ice at night. Solar during the day
in rocks and salt for night heat is storeage. Also, advanced batteries and SEMS superconductors for electricity storeage
are needed.
I applaud the recent decision by the Energy Department to
fund FORO technology to drill geothermal wells for power.
I support the development of geothermal wells as they will
provide clean power cheaply if we develop them.
Maybe even geo nuclear with geothermal and nuclear to give
the end boost of power to a geothermal plant.
We can cut through the above confusions by using the Thermodynamic Razor: All earth-energized technological ordering results in an overall loss of order.
Reply | Report Abuse | Link to thisThis means Jacobson and Delucchi are correct in only looking at relatively direct solar (which includes their wind and water sources).
This approach excludes all fossil fuels, geothermal, nuclear, and the lesser evil of biofuels (since they only delay deployment of relatively direct solar).
Hydrogen fuel (if produced via solar) can be stored interstitially for transportation uses and released by temperature changes (from exhaust) upon command.
The above solar sources are already cost competitive if the entropy costs are included. For example, add 4 cents/KWH to coal for logistics and another 4 cents/KWH for global warming. Wind is already competitive.
We have no choice--go solar or decline.
The cost of solar retooling is a necessary investment that is paid back through energy sales.
I think that covers it.