This paper has most influenced my thinking about our energy future. I noted that in the 1930s, one could get 100 barrels of oil from the energy in one barrel of oil. By the 1970s, that had declined to 30 to 1 and now it is around 10 to 1.

An excerpt from that paper:

What is the Minimum EROI that a Sustainable Society Must Have?

Charles A. S. Hall *, Stephen Balogh and David J. R. Murphy
Program in Environmental Science, State University of New York – College of Environmental Science and Forestry, Syracuse NY, 13210, USA

Energy surplus is defined broadly as the amount of energy left over after the costs of obtaining the energy have been accounted for. The energy literature is quite rich with papers and books that emphasize the importance of energy surplus as a necessary criteria for allowing for the survival and growth of many species including humans, as well as human endeavors, including the development of science, art, culture and indeed civilization itself. Most of us who have thought about this issue deeply would even say that energy surplus is the best general way to think about how different societies evolved over time.

The trend is unmistakeable, and it’s what made me realize how important geothermal is to our sustainable future.

Geothermal has an Energy Return on Investment (EROI) of 10 to 1 and unlike fossil fuels, which will steadily decline, that won’t change for centuries. Very few people in the world are lucky enough to have this option.

When coming to the fork in the road where one choice is geothermal, the survivor types – the rubbah slippah folks – will naturally take the geothermal turn.

If we were to take the other fork, our electricity and water costs would rise and rise until there was no more. People would start to leave the electric grid. Our schools would not be able to afford the electric rates, and they would have to turn off the air conditioning and the kids would have a hard time learning. The poorest among us would have their electricity and water tuned off.

Down the geothermal road, however, the grass is always green. Our electricity and water costs will stay the same as they are today – for centuries. After awhile, our everyday living costs would be cheaper than those on the mainland.

Because our low income folks would have extra money, our businesses would start to grow. And as our electricity costs became lower relative to the U.S. mainland, we would be more competitive in manufacturing and things that use energy. Most of us would be cruising around in hybrid electric cars.

It’s perfectly clear that we need to go down the geothermal road. My Pop used to say: “Get thousand reasons why no can; I only looking for one reason why can!”

Here is the Puna Geothermal Ventures website. The company is run by local folks and its manager is Mike Kaleikini. They are good community citizens.