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|Keywords||Energy, Energy efficiency, Renewable energy|
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|Cite as Chris Watkins (2021). "Limits of energy availability and efficiency". Appropedia. Retrieved 2021-10-24.|
Can we trust in technology to provide us with abundant energy with no environmental impact?
Improving the availability of work[edit | edit source]
The availability of work is a function of our ability to harness concentrated energy. Concentrated energy takes many forms: food, wood, coal, fuel gas, oil, etc. Civilization has become progressively more complex as the ability to harness increasingly concentrated energy sources has made more work available. Work is the building block of complex civilization. Today, however, there is mounting evidence that diminishing marginal returns on our use of concentrated energy is decreasing the availability of work that can be applied toward creating quality of life. Aspects of this phenomena are often called "peak oil," "peak coal," or "peak energy." A peaking in world energy production - without a concomitant reduction in human population - suggests that humanity will be challenged to maintain, let alone increase, quality of life in the future.
Improving energy efficiency[edit | edit source]
What about improvements in energy efficiency? There are two reasons why improvements in efficiency will not solve this problem. First, the Jevons paradoxW tells us that at least some of any improvement in efficiency will be self-negating, as improvements in efficiency free up some of the energy resource, decreasing demand, which lowers its price, which increases consumption. Second, efficiency (per second law of thermodynamics) can never reach 100%, so there is a strict limit on how much we can improve efficiency. Let's say, for the sake of argument, that the global average for efficiency for conversion of energy to work is 30%. If one accepts the second law of thermodynamics, then it is impossible to improve this number to 100%. It seems highly unlikely that this number will ever approach anything close to 100%, leaving us with well less than 70% to work with. While that may seem like a huge jump, consider this example: what if we could convert our automobile fleet from averaging 30 mpg to averaging 95 mpg? Would this eliminate the problem of peak energy? Even IF automobiles were the only relevant energy users, this would only have a short term effect - much of the gain would be negated by the Jevons paradox, and even without the Jevons paradox it would, at best, triple the time that our resources last. Efficiency will not save us. That isn't to say that improving efficiency has no place in solving our problems, but rather to put it in its correct place: efficiency buys us time to treat the problem. Efficiency also makes expensive energy (e.g., renewables) more affordable, which is why efficiency tends to increase when the cost of energy increases.
Alternative energy sources[edit | edit source]
What about "alternative energy" sources? First of all, for any alternative energy source to be part of the solution (a true "alternative"), rather than part of the problem, it must have an EROEI (Energy Returned on Energy Invested]]) of greater than 1, and can be applied on a large scale. This may be highly controversial, but it's not clear that such resource exists that meets both criteria.[verification needed] Jeff Vail has written about the difficulties of calculating EROEI, arguing that most EROEI numbers today are artificially high because of a "bootstrap effect" of using high-EROEI fossil fuels in process of bringing "alternative" energy to market. There do seem to be some renewable, "alternative" energy sources that have an EROEI greater than 1 - wind and hydro come to mind - but they face severe limitations. Regardless of the exact EROEI of the various "alternatives" currently being proposed, there is little debate that these will provide an EROEI in excess of that once enjoyed in oil and gas production. If externalities such as climate change, topsoil depletion, and water use are accounted for, it seems (to some observers, at least) likely that our aggregate societal EROEI will continue to decline until it reaches some point of stasis slightly over 1. If this is right (and of course we hope it isn't) then "alternative" energy will not keep us living in our "happy motoring utopia," and certainly won't allow the rest of the world to rise to that standard of energy consumption (note that this is not equated directly with quality of life…).
Overall, when faced with these challenges in the areas of efficiency and declining EROEI of "alternatives," it might be concluded that the solution to our energy problems will not come from the "improving the availability of work" portion of the quality of life equation. Rather, to the extent that our energy problems are "solvable," the solution seems likely to come from improving technics - improving how we use the energy that we do have to create quality of life. Reasonable people can disagree with the conclusions regarding efficiency and EROEI, but we just don't know - anyone who claims to KNOW the answer is discussion theology, not science. But regardless of the answer to the energy question, it seems very likely that there is ample room to improve our technics. IF we accept this latter proposition - that we can improve our utilization of energy to create quality of life - then doesn't it make the most sense to focus our mitigation efforts there? Some of us have great confidence in the power of human ingenuity to solve our problems. However, when human ingenuity meets the laws of physics and thermodynamics, these will not bend to our will. Design of technics, on the other hand, seems to be an area where human ingenuity has unending room for advancement.
- Follow this analysis further at Quality of life through design and "technics".