Geothermal energy and climate change

Congressman Raul Grijalva organized a Climate Change Roundtable in Tucson last Friday, the same day the latest IPCC report on climate change was released.

A couple dozen of us were invited to briefly talk about the impacts of climate change or options to counter them. I was asked to cover geothermal energy.

Geothermal energy has the potential to meet the nation's entire energy needs many times over. Geothermal power plants produce only 60 lbs of CO₂ per MWhr of electricity produced compared to 1212 lbs for existing power plants and 850 lbs for new plants, which is approximately a 92-95% reduction of this

Geothermal map of North America(American Association of Petroleum Geologists, 2004)

greenhouse gas. When geothermal energy is used for direct space heating or in geothermal heat pumps, the production of carbon dioxide is even less.

Geothermal is also “24/7” – it can be part of a utility’s base load, which is a critical factor in utility’s being able to meet state and federal requirements for delivering power.

Arizona has little high-temperature geothermal potential but large untapped low to moderate temperature resources, particularly with Enhanced (or Engineered) Geothermal Systems (EGS) and Geothermal Heat Pumps.

But research is needed to develop EGS technology to make it cost effective and practical.

And heat pumps are less efficient and more costly in desert areas like Arizona because the
watertable is deep, requiring more coils to be buried in the ground or deeper holes drilled to reach the water. Therefore, tax incentives to homeowners and businesses could be critical to widespread installation in areas like Arizona.

Federal funding for DOE's Geothermal Technologies Program was zeroed out in the President’s FY08 budget for the second consecutive year. Federal programs are spending their remaining funds closing down, archiving files, rather than working on their core functions. Staff researchers are finding other jobs before the federal programs close their doors. Will we be able to lure them back if funding is restored by Congress, or will they stay in more secure jobs elsewhere?

My recommendations for Federal action, as requested by Rep. Grijalva, follow the general lines of those urged by the Western Governor’s Association:

1. Geothermal research by the Federal government should be stabilized and increased into technologies that can reduce risk, reduce costs, or expand the accessible resource base.

2. Better resource information is needed in an easily accessible, integrated, interoperable online data network.

3. The Department of Energy’s GeoPowering the West initiative should continue to support efforts for utilization of the West’s untapped geothermal resources.

4. Federal tax credits and incentives and timely permitting and environmental reviews are critical to expanded marketplace development.