Wednesday, March 28, 2007

Presentation: "Future of Geothermal Energy"

The following summary points were given on March 1, 2007 as part of a slideshow presentation at the National Renewable Energy Laboratory (NREL). Advantages of enhanced geothermal systems (EGS) — power plants in 'low grade' settings where the hot rock source is deeper in the earth — are listed as follows:

  1. Large, indigenous, accessible base load power resource — 14,000,000 EJ of stored thermal energy accessible with today’s technologies. Key point — extractable amount of energy that could be recovered is not limited by resource size or availability
  2. Fits portfolio of sustainable renewable energy optionsEGS complements the existing portfolio and does not hamper the growth of solar, biomass, and wind in their most appropriate domains.
  3. Scalable and environmentally friendly — EGS plants have small foot prints and low emissions — carbon-free and their modularity makes them easily scalable from large size plants.
  4. Technically feasible — Major elements of the technology to capture and extract EGS are in place. Key remaining issue is to establish inter-well connectivity at commercial production rates — only a factor of 2 to 3 greater than current levels.
  5. Economically favorable — projections favorable for high grade areas now with a credible learning path to provide competitive energy from mid- and low-grade resources
  6. Deployment costs modest — an investment of $200-400 million over 15 years would demonstrate EGS technology at a commercial scale at several US field sites to reduce risks for private investment and enable the development of 100,000 MWe.
  7. Supporting research costs reasonable — about $40 million/yr needed for 15 years — low in comparison to what other large impact US alternative energy programs will need to have the same impact on supply.