Net Energy-what Captain Cook didn’t know
In June of 1778, Captain Cook’s search for the Northwest Passage brought him to the later-named Cook inlet near my home, Anchorage, Alaska. As he sailed up the arm (fjord) and reached the end, he discovered that there was no outlet. After days of being stuck due to wind and fog, he had to TurnAgain, hence the name of the arm. Captain Cook never found the Northwest passage, and he never saw England again. He died the following year in the Hawaiian islands after picking a fight with Hawaiian Islanders.
We are not quite out of gas yet in the United States. But we keep steaming down fjords without outlets, turning randomly from one blind alley to the next in trying to adapt to our energy quandary. In Captain Cook’s case, he was exploring with zero information, so there was a good chance of failure. But when it comes to energy alternatives, we can avoid dead ends, since we have what Captain Cook didn’t have, information on the best alternatives. This post is about the science of net energy regarding those options.
We are now trialling many unworkable alternative energy sources, as a response to government subsidies and agendas promoted by various energy lobbies, often in pursuit of short-term profits for private companies. Should we be letting private energy companies with vested interests dictate future energy policy which could make the difference in continuing to exist as a country? Which so-called renewable energy sources have yielded practical returns on investment, withstanding the test of time? There is a 50-year body of research on the subject of net energy. Shouldn’t we be using science and not vested corporate interests to set energy policy?
In the last post, I suggested that if one doesn’t understand the problem of declining net energy (empower basis), then growth is not viewed as a problem. Even our oil companies now openly advertise that we have produced the easy half of the oil available to the planet, and we will be producing less in the future since we have peaked. Less oil and other resources means that our economy will have to contract in the future, since renewable energy suffers from lower energy density and quality. Since we are entering energy descent, practical energy sources are beginning to sort from the impractical. Because “the true value of energy to society is the net energy, which is what is left after the energy costs of getting and concentrating that energy are subtracted,” we must decide net yield to make proactive choices about the future (Odum, 1973). Odum developed the concept of net energy and then refined the idea over the span of 50 years. The name of the analysis changed several times beginning with the term net energy then to embodied energy and finally to the term emergy yield or net empower to account for more inclusive changes in method, so many don’t recognize that the terms were developed over time from the thinking of the same community of scientists.
The primary goal of this post is to suggest that many purported energy source predictions of net yield are overly optimistic dead ends–many of our current efforts won’t work. The second goal is to suggest more reasonable net empower estimates, and to briefly check the performance of renewables from the proving ground of time. How did these experiments in energy work out for us?
What is net empower yield?
The science of net energy is vulnerable to specious claims from companies who make the devices under scrutiny. Readers may opt to fasten hopefully on the largest net claims as the most probable. As resource availability finally surfaces into the conscious mind of the average American, we are starting to hear claims about the viability of different sources based on very little evidence. Many suggest that nuclear power is our best alternative, with very high net energy. Wind energy has a net ratio of 20:1. Or 30:1. Or solar photovoltaic (PV) will become profitable when the cost of oil gets higher. Or, for the mathematically challenged, we can replace the entire motor fuel supply of the US with biodiesel from pond scum. It’s time for a reality check.
Brown, Cohen, and Sweeney summarized the science of net emergy in 2009, so I will cite heavily from that article.
“Net energy of any process including energy sources is calculated using an Emergy Yield Ratio (EYR) (see Odum, 1976; Brown and Ulgiati, 1997) which is the net contribution of an energy source to the economy. Hall et al. (1986) introduced a similar concept called Energy Return on Investment (EROI), although different from EYR in that it does not include quality correction and other inputs such as labor and environmental contributions” (Brown, Cohen, & Sweeney, 2009, p. 3426).
It is essential to calculate all costs of energy sources to avoid undue optimism about potential renewable alternatives. Because there is a range of reported energy yields reported, we need to consider the source of reports. If we do not include nature’s contributions to net energy/empower calculations, we will try to use energy sources that damage the environment, as is now shown with market failures with ethanol, solar PV, oil shale and gas, tar sands, and nuclear. Odum calculated almost 40 years ago that solar PVs and oil-shale were net negative–history has borne that out, with failing industries littering the landscape. The fact that tar sands, ethanol, and solar PVs (as opposed to solar thermal or passive solar) exist doesn’t make them net positive. Subsidies and favorable government policies allow short-term profits from net negative projects. Overall emergy yields are declining over time, as shown above.
I’ll spotlight nuclear power, since nuclear is a blind spot for the American public. Approval for nuclear power in the US was at its highest ever in 2010, especially among men. Apparently energy policy is a popularity contest. We can’t even calculate the emergy yield for nuclear, since we can’t dispose of the wastes or decommission the plants. Nuclear power plant meltdowns could be a catastrophic crisis that comes out of left field in the 21st century. Are we going to manage these plants into perpetuity, besides the many other problems of nuclear discussed here? Nuclear power appears to be a dying industry in Japan and the US. Odum’s early words on the net yield of nuclear have been born out by circumstances in Japan.
“No one really knows the net yield of nuclear power because at present its use is subsidized by fossil fuels in a thousand ways that cannot be estimated until we try to run a nuclear system without them. Will nuclear power have a more concentrated value than the wood output of the solar system, or of coal, or of cheap oil from rich deposits? The new power plant seems to be more economical than the competing fossil plants as long as it is running on the accumulated storages of nuclear fuel and fuel prospecting done on fossil-fuel subsidy. Is nuclear power at this level of net power delivery possible in a culture that does not have the accompanying fossil fuels” (Odum, 1971, p. 135)?
An emergy yield ratio of less than one indicates a loss of emergy from that energy source for society. Using EYR to calculate renewable alternatives “provides a relative relationship for evaluation of green-house gas emissions. For instance if we assume that ethanol with an EYR of 2 to 1 is used to replace fossil fuels having yields of 8 to 1, the ethanol is actually using energy at four times the rate, and increasing greenhouse gas emissions over the burning of the fossil fuel” (Brown, Cohen, & Sweeney, 2009, p. 3429). Many so-called renewables actually guzzle fossil fuels.
Electricity is the defining line between an information society and something less complex. How do we keep the power humming? Renewable energy sources suffer from low emergy yields, distribution, intermittency, flexibility, and other problems (Cleveland, 2007, Fridley 2010). Brown et al. suggest that renewables will not replace traditional forms of energy, and that coal suffers from optimistic over-estimates due to failure to calculate net emergy and liquid conversion requirements; they estimate coal reserves of 100 years or less. Electric power has impacts on land, water, air, and climate, as do renewables (Keith et al., 2012). Many proposals to scale up marginal renewables to supply electric power have not panned out. Odum suggested that over the long-term, the best hope for maintaining centers of information was hydroelectric power.
What do we do with this information?
We can detect a pattern here. Wherever we are attempting to use marginal energy sources even with sophisticated technologies, devastating industrial scale environmental impacts and device/extraction company bankruptcies result. When we drill oil wells at 20K to 35K feet, we should expect gas blowouts. If we continue to double stack spent fuel pools perched on top of nuclear reactor vessels that are past their due dates, then we should expect catastrophic meltdowns. If we hydrofrack natural gas at 8K feet using toxic chemicals, we should expect contaminated aquifers. The net emergy yield of ethanol is less than 1, so attempts to scale up ethanol result in ocean dead zones, topsoil loss, usurped water and land, and increased pesticide contamination. Solar panel production is so dirty that the Chinese shut down a factory due to protests, but since Americans have exported the environmental costs of PV manufacture to China and have subsidized the cost of purchase, neither the net negative yield nor environmental costs are apparent. Tar sands only work if we cannibalize from pipelines of high quality natural gas to convert net negative tar sands into something we can shove into our gas tanks. It takes more energy to make the solar panels or cook the tar sands than we get out of the final product. And in our Rube Goldberg economy, as useful power declines from marginal energy sources, environmental costs will continue to rise. As Aldo Leopold said, “Having to squeeze the last drop of utility out of the land has the same desperate finality as having to chop up the furniture to stay warm.”
What does this mean for people interested in renewable technologies for their home? Individuals can buy negative yield technologies such as a solar PV panel or expensive new electric car if they are wealthy and have money that is not needed for other lower order needs. Solar PV is either net negative, marginal, or slightly positive, depending on methodology and age of the study. For those who insist that solar is significantly positive, consider the string of recent bankruptcies in subsidized solar companies. For those who need further convincing, here is a recent study placing solar at marginal or negative in emergy yields. For marginal energy sources we are wiser to “spend” the energy more equitably elsewhere in a contracting society. Net negative technologies can be used at the small scale without sapping too much emergy from the economy, but attempts to scale up with a desert full of solar panels would quickly become too energy intensive and thus also prohibitively costly, even though cost is not a true measure of the drain on society. Nature has optimized the best way to optimize solar energy for maximum power through photosynthesis. Perhaps we are seeing a focus on attempts to expand industrial scale PV because that is how the existing corporate utilities make money. Social justice can wait.
As our economy gets worse, and money gets tighter, people will probably choose to fund other more basic needs and not expensive technology to build personal resilience. In our contracting economy, we will have less capital for high-tech investments, not more. Reducing energy use in our basic needs is the first answer, in our transportation, our housing, and our food, through relocalization, growing our own food, and other creative solutions. If you are reliant on fossil fuels for basic needs, consider back up systems or simpler renewable alternatives that are available locally.
We need to reduce and simplify in all parts of our lives, not just in energy use. Since energy is embodied in everything in our complex society, reducing our energy means reducing the complexity of our homes, our businesses, the technology that we use, and the digitization. As Tainter suggests, we are experiencing a diminishing return at this point on complexity. More complexity will only add bureaucracy and make systems vulnerable to collapse. When there is a choice to add digitization and technology to your business or personal life, consider whether it adds anything useful. The favored phrase in my specialty these days is, “healthcare is broken.” Increasingly, systems attached to the empire will appear broken or too expensive as we add the last piece of computerized health record or new division of toothless regulations that becomes more work than it is worth.
If I was a politician, I would begin a national campaign to educate the public about the limits to growth and the need for a prosperous new way down. I would consider the alternative policy routes carefully. If we make an error at the national scale as to what energy sources we choose to support, we will create a huge drain in terms of mal-investment and environmental degradation. Making such an error with one’s personal budget might mean you move back in with your family. Making the error on the scale of country may result in one or more outcomes of war, poverty, famine, or epidemic. And “all of the above” is not a good energy policy when many of the supposed solutions not only drain emergy from the country but also funnel wealth into the hands of the wealthy. Attempts to return to economic growth at this point are combatting thermodynamics. Since the world’s pie of resources is shrinking rapidly, the only way for the US to return to economic growth is to steal an increasing part of some other country. The only way that we will be energy independent in a future of declining resources will be simpler living. “The only genuinely sustainable energy scenario is one in which energy demands do not continue to escalate indefinitely” (Stover, 2011). Boosting energy production through solar PV or biofuels or fracked gas will leave us with no environment to fall back on when fossil fuel supports decline. There is a difference between promoting realistic hope and promoting unrealistic hope based on faith that something will show up to save us in spite of the evidence our science reveals.
For our country, we’ve done a great job of using everyone else’s resources after our oil peaked. Unfortunately, we should have used the time to build the infrastructure and the cultural know-how to live within our means. Creating a new society takes time (Smil, 2012). Now, instead of having an ecologically congruent culture and lifestyle, we have a system adapted to using 25% of the world’s oil for 4% of the world’s population. There is nothing fair about that, and we are getting ready to pay the piper for our party. None of our renewable alternatives will allow us to keep our current level of society. Hall, Balogh, and Murphy (2009) suggest that we need a level of EROI of 5:1 from main fuels for a sustainable society. Using the emergy synthesis approach, Brown suggests that a net empower limit for society overall (not just for energy sources) might be an empower basis of 3 or 4. As oil exports from other countries wane, the US is going to have to get Manhattan-Project-serious about our quandary if we are to rescue any residual information centers from the ruins. We need 30 million more small farmers in this country, since industrial agriculture grows “potatoes made of oil.” We need to revitalize our lower energy transportation such as the railroad industry, and we need to wean ourselves off marginal, environmentally hazardous energy sources such as nuclear, fracked natural gas and biofuels. Many more suggested policies are on this webpage.
Hope that there are easy, renewable market solutions prevents us from feeling the sense of urgency necessary for the large-scale infrastructure change that we will need to keep even a fraction of the complex information society that we now have. Approximately 71% of whole earth empower comes from fossil fuels, so eventually we will have to live on about a third of our current emergy basis (Odum and Odum, 2001). Even among those who understand peak oil, there are many who believe that technology will save us. Brown et al. refute that false hope. Even if we were to find a magic pill, more growth would result in declining quality of society due to environmental degradation.
“In industrialized economies today, emergy use per capita is almost 1000 times the emergy per capita of people living 100 years ago. Technological improvements go hand in hand with increased energy demand. We are convinced that humans will strive for any number of potential solutions to the energy dilemma. Money and energy and human ingenuity will be invested in the hopes of finding a new energy source or a more efficient process of utilizing existing sources. If it is found it means more of the same, more growth of demand, more consumption, greater amounts of waste, and increased environmental load. The growth of wastes and environmental load if dealt with will decrease available energy that can be directed toward production of goods, services, and infrastructure for humanity, so that the end may not be much improved quality of life or human welfare” (Brown, Cohen, & Sweeney, 2009, p. 3437).
As an American, I know that the US is on tenuous ground about energy availability. Our oil production peaked in 1970, and we have borrowed resources from the world since then using a petrodollar backed by military might. We base our currency on an IOU to the next century that we will not be able to pay. We will default our unpayable promises to the future, and complex constructs of the 20th century will disappear, starting with large chunks of the financial, insurance, and real estate industries. We don’t have time to go down any more cul de sacs blindly chasing profits that are funneled to wealthy corporate managers. We need policy that is clearly focused on descent, so that we can relocalize in communities and save some of the high density fossil fuels for our grandchildren. Instead, we’re burning it out of our tailpipes at the rate of 80 million barrels per day (20 million in the US alone), as we explore like Captain Cook from dead-end fjord to blind alley to suburban cul-de-sac.
We will soon be like Captain Cook, out of time and supplies and unable to go forward. At least his ride operated on wind, allowing him to Turnagain and again. Instead, we are burning up the last rays of ancient sunlight, looking for the holy techno-grail of the Next Big Thing, which is actually going to end up being a lot smaller instead.
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