IN HOT WATER: Temperatures can reach 430 degrees Fahrenheit at the depths geothermal pumps are submersed.
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What will it take to develop a geothermal pump that can operate miles underground in 430-degree-Fahrenheit fluids while maintaining a steady 750 horsepower?
A pair of West Coast foundations hope they have the answer: lots of cash.
The Oregon-based Foundation for Geothermal Innovation and the California-based Lemelson Foundation last week released design criteria for a race to build the next generation of "temperature hardened" electric submersible pumps (ESP), one of a number of technologies crucial to the advancement of geothermal energy on a commercial scale. The groups are prepared to offer millions of dollars to the first firm to develop an ESP that can withstand extreme subterranean heat and pressure.
"Energy from geothermal resources is affordable and abundant," said Patrick Maloney, senior program officer at Lemelson. "But the problem to date has been harnessing it. This report will hopefully provide companies and individual innovators the parameters needed to solve a key part of that problem."
The report is a result of a meeting held earlier this year at Stanford University that brought together 20 top experts in the field, including representatives from government, academia and the private sector, to look for ways to reduce fossil fuel use through an expanded adoption of geothermal.
Pump companies, universities and inventors are being asked to compete for a $5 million prize purse to be awarded in 2015. The winning firm will also receive an advance market commitment for 100 pumps, a $75 million order designed to serve as the chief incentive to innovators.
"It is rare to find a key technical challenge that can be so clearly defined for innovators to work on," said Lawrence Molloy of FGI, which is seeking support from the Department of Energy in building an incentive package to be finalized in early 2010. "We hope that this prize can help revitalize the industry."
Similar targets for geothermal pump development have been set by the Energy Department's Geothermal Technologies Program, which has found current pump models unable to sustain flow rates under advanced geothermal conditions. While geothermal resources can reach 660 degrees, pumps capable of delivering heat from below ground are designed to operate at just 375 degrees.
Enhanced geothermal systems
The new pumps are critical for "enhanced geothermal systems," in which energy is produced by fracturing dry rock at the bottom of a deep hole and then circulating water through the cracks to generate steam. In contrast, today's geothermal projects use hydrothermal systems that tap naturally occurring water deposits to provide geothermal heat.
While hydrothermal potential is estimated to be about 30,000 megawatts, the potential for EGS is greater than 500,000 megawatts, or about half of the current generating capacity of the entire United States, according to a 2008 report from the U.S. Geological Survey.
A seminal 2007 study from the Massachusetts Institute of Technology found that wide-scale commercial deployment of EGS reserves could power more than half of American homes by midcentury. And unlike intermittent wind and solar power, geothermal is available around the clock and requires much less real estate to develop.
"Geothermal energy from EGS represents a large, indigenous resource that can provide base-load electric power and heat at a level that can have a major impact on the United States while incurring minimal environmental impacts," according to the MIT study. "Further, EGS provides a secure source of power for the long term that would help protect America against economic instabilities resulting from fuel price fluctuations or supply disruptions."
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8 Comments
Add CommentThis article makes a strong case for EGS. I prefer nuclear over wind and solar. A technology like this might make me venture away from nuclear.
Reply | Report Abuse | Link to thisWhy is this even necessary? I would think that it would be more efficient to have the pump at the surface pumping relatively cool water down to be heated. The heated water would then return to the surface without the need of a pump at the bottom.
Reply | Report Abuse | Link to thisTTLG - You are correct. This is a left over from the Bush administration to delay all alternative energy sources so they can maintain controll and keep the price of oil high and America oppressed, and dependent on war lord countries and the Bush war effort. All they have to do is pump water into the hole from the surface and the steam will come to the surface by itself and hit the turbines and generate electricity. They do not have to pump the steam up from the bottom. They can even recycle the steam and use the water again, eliminating even more of the chemicle pollution from the bottom rock and preventing the tropical effect around the plant. Geothermal always was and still is the best and cheapest way to produce electricity.
Reply | Report Abuse | Link to thisWhile geothermal has some possibilities like nuclear fusion it will take far too long to develop. In fact, dirt cheap pulse fusion reactors like Paul Allen's TriAlpha Energy will likely be around long before geothermal of this type can become cost effective.
Reply | Report Abuse | Link to thisHard to beat mass produced nuclear power at 2 cents a kilowatt that is here today and ready to go. All that is required is political action to clear the road blocks.
Ones and twos of reactor builds requiring individually years of approvals from multi levels of bureaucrats and corrupt politicians and billions in attorney costs separate us from an effective nuclear attack on global warming.
Google China, Westinghouse and nuclear and you'll see how it can be done.
Scientists are telling us that there is some chance we are as little as 10 years away from falling off a climate precipice with permafrost methane emissions and ocean acidification forming the leading edge of a very steep slope. A massive switch to nuclear tech is our only answer in this time frame.
While geothermal has some possibilities like nuclear fusion it will take far too long to develop. In fact, dirt cheap pulse fusion reactors like Paul Allen's TriAlpha Energy will likely be around long before geothermal of this type can become cost effective.
Reply | Report Abuse | Link to thisHard to beat mass produced nuclear power at 2 cents a kilowatt that is here today and ready to go. All that is required is political action to clear the road blocks.
Ones and twos of reactor builds requiring individually years of approvals from multi levels of bureaucrats and corrupt politicians and billions in attorney costs separate us from an effective nuclear attack on global warming.
Google China, Westinghouse and nuclear and you'll see how it can be done.
Scientists are telling us that there is some chance we are as little as 10 years away from falling off a climate precipice with permafrost methane emissions and ocean acidification forming the leading edge of a very steep slope. A massive switch to nuclear tech is our only answer in this time frame.
TTLG asserts the notion of pumping cool water from the surface and obviating the need for a downhole pump. Unfortunately, the subsurface geology and geothermal reservoir dynamics still necessitate pumping heated fluids from depth. Lineshaft pumps are limited to ~2000 feet because of torque issues. An alternative method is needed.
Reply | Report Abuse | Link to thisLawrence Molloy
Executive Director
The Foundation for Geothermal Innovation
I suppose that to pump a fluid/gas mix down a small diameter pipe; as opposed to a fluid by itself down; to the heat zone by which to create a steam/gas mix to be forced up; and done again through a small diameter pipe or sets of pipes; would have problems of its own.
Reply | Report Abuse | Link to thisI mention this, because by using a hydraulic ram pump we are able to pump water up a half-inch pipe at a faster rate and higher lift with the air/water mix than could previously be done in a one-inch pipe with the water alone being forced up by the same pump that lifts our water up by the force of water hammer to a 300 foot higher elevation.
Not to say that a hydraulic ram pump would suffice for the required task, but that the restrictions of a small pipe force the fluid to climb upwards with bubbles of gas not being able to slip around the sides or through a central area where pipe wall friction would not be a contender. Steam and a gas would likely mix well and would be seperatable by a gravity or centrifuge system.
Would that the forcing of a gas down to the heat zone was to be contemplated, then what chemical reactions would be encountered by using the effluent from a coal fueled EM generating system: CO2 effluent?
The Ancient One
The heat underground, comes, mostly, from the core of the Earth. It's the reason why it gets hotter the deeper down you go. It doesn't really come from the sun directly by heating the ground, although the ground is heated, it is also cooled, the core stays pretty consistently hot. I suppose, very indirectly, the heat comes from the Sun as the core is only stored heat-energy resulting, mostly, from the creation of the Sun. Its always good to see movement of issues like this, especially when it means, humans might really be gaining a strong foot-hold on this solar system.
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