The Acronym you may not know but should: EROI
Don’t know what this totally sexy acronym means? Excited to learn? Hope so! You are going to be SO excited knowing this! [Teaser: There is another definition of EROI for those who prefer less technical issues]
Energy return on investment (EROI) is a ratio that measures the amount of usable energy delivered from an energy source versus the amount of energy used to get that energy resource.
Disappointed? You shouldn’t be. You now have the concept that will enable to understand why we live better than Kings did 150 years ago. You see, modern society was born a hundred and fifty years ago when coal began providing sufficient energy to make lots and lots of steel and steam, lifting ordinary citizens out of poverty and into the newly-developing middle class. Soon after, we added oil. The energy obtained from these sources was obvious and immediate. It took little energy input to get a lot of energy out. In 1930, 1 joule of energy put into oil got 100 joules of energy out, an EROI of 100. Similarly for coal. The economies of the industrialized world became super-charged by fossil fuel, and their standard of living increased proportionately. In only a few generations, the planet had a billion middle-class humans.  The problem is, energy sources with high EROI have waste problems – like CO2 or radiation – that make the side effects of the energy production “problematic” [to be polite].
The graph below compares the EROI of our most popular energy sources. Because some sources require buffering, storage or load-following, there are two values for each source, with and without energy storage or buffering. For societal needs, the buffered value, or the value with energy storage, is more representative of the EROI. Notice a problem? All the “bad” energy sources have a high EROI while all the good energy sources [as of today] have a low EROI. Is this a problem? Yes – it’s a HUGE problem. Our high standard of living, high populations, huge cities and long life exist only because of high EROI energy. Weißbach  calculates that this minimum viable EROI is about 7 for the United States and the European Union. Lower EROIs cannot sustain our society at our level of complexity or our standard of living. America’s present EROI averages about 40. A mix of 50% renewables, 30% fossil and 20% nuclear gives an average EROI of about 25.
What does this mean for you? Quite frankly, to “save the world from global warming” your standard of living is going to have to go down – that’s what a lower EROI will do. Sorry. It also means that unless the EROIs of renewables increase dramatically elimination of fossil fuels means we will have to increase our reliance on nuclear energy – an unpopular political option. The magic number “7” is clearly a problem for renewables, for, as stated above, it is “magic EROI number” needed to sustain our complex society and no renewables currently have an EROI of 7 – except for solar CSP and hydro. I don’t have to explain hydro to you – assuming that you are a Canadian. But, CSP? Lucky you! You now get to learn another acronym: Concentrated solar power (CSP, also known as concentrating solar power, concentrated solar thermal) systems generate solar power by using mirrors or lenses to concentrate a large area of sunlight onto a receiver. Electricity is generated when the concentrated light is converted to heat (solar thermal energy), which drives a heat engine (usually a steam turbine) connected to an electrical power generator. This schematic makes it clear. CSP is very popular in Spain, but not elsewhere. Which is not only a shame – it should be much more widespread than solar PV. Of course, much of life makes no sense, I know that, but once you REALLY understand the implications of EROI you will understand that CSP, not wind or solar PV, is a better bet for our renewable energy future.
However, even if we build lots of solar CSP, increase the EROI of wind and solar PV, develop more hydro projects [which have their own problems – ask Newfoundland whose Muskrat Fall hydro project was bankrupting the province, until the Federal government helped them to the tune of 5 billion $] it still means we are stuck with needing politically unpopular nuclear which, as we all know, has “issues” [that is an understatement]. There is more bad news. Even if we stick to fossil fuels we are in EROI trouble. Why? Today U.S. oil is produced at an EROI of about 14:1, according to Hall and Day. [remember, it was once 100:1] The EROI for Athabascan tar sands in Alberta, from which a million barrels per day of oil is now being produced, is just 6:1, according to Canadian petroleum geologist David Hughes (as quoted in the January 7, 2011 issue of The Walrus).
Can I be honest? It also means that, even assuming the best from human nature and political reality, that we are in for bumpy ride with a probable reduced standard of living for the West and outright poverty for those in the 3rd world who have just extracted themselves from poverty by the use of cheap, and high EROI, coal and oil. Eliminating fossil fuels is a must, not only because of global warming but because the EROI of modern oil fields is so low – but the electorate is not going to understand that. The problem is that meeting our 2050 zero carbon goal is going to make a lot of people very poor and VERY UNHAPPY. Of course, not doing so will actually make them, in the future when they become climate refugees and are subjected to famine, even unhappier. But that is in the future, and human nature, given what it is, discounting the future means eliminating fossil fuels will be a very hard sell. Clearly, our political leaders, who think short term, are not going to like the choice of a lower EROI renewable energy mix as the chances of an unhappy electorate voting for them is about as high as the Cheshire cat appearing magically in the tree outside my window with my good friend Alice.
So, what CAN YOU DO? First, the normal stuff. Reduce your energy needs. Live simply. Travel less. Stop eating beef. Add to this personal list the issues that are in the Public domain and have more impact. Push government to invest in energy conservation and mandate high efficiency in all energy consuming devices. Stop being afraid of nuclear – but make sure it’s done right! Most importantly, don’t get depressed when we become materially less wealthy – a high quality of life is still possible without being the energy hogs we are now. You can, believe it or not, still be happy without your SUV or truck [that’s 70% of Canadians] or annual Florida/Caribbean vacation! Teaser Time! Here is my personal second definition for EROI that is slightly less technical:
Emotional Energy Return on Investment:
The ratio of energy you receive from a relationship as compared with the emotional energy you put in.
In our society this ratio too has been decreasing – dramatically! How do I know? Do I have data? Yes. The Divorce rate.. The number of persons living alone in Canada has more than doubled over the last 35 years. Anxiety. Depression. Drug/Alcohol abuse. Pornography. Gambling. People texting instead of talking. Family members watching movies individually on their devices instead of together. All these social ills, at their root, have to do with the destruction of the social ties that bind us and keep us emotionally stable and satisfied. Our focus on material wealth – high EROI [the technical version] seems to have decreased our Emotional EROI. Clearly, we need to refocus on our Emotional EROI. Invest in your relationships, your family and friends, the energy you put into them will increase your Emotion EROI which will certainly improve your life more than any material EROI. This will give you positive emotional energy – which you are really going to need for the bumpy energy transition ahead.