This post is the first in a series on structural problems of transitioning to renewable energy. Broadly labeled “The Renewables Hump,” this series will address net energy, scalability, bootstrapping, and time-frame considerations involved in such a transition.
The requirement (and problem) of up-front investment.
To the extent that America (and the world in general) is concerned with energy scarcity at all, there is a pervasive belief that, over the coming decades, we will overcome these challenges by gradually transitioning to a renewable-energy economy. We know that fossil fuels won’t last forever. We know that it is possible to generate renewable energy from sources such as the sun, the wind, waves, and geothermal heat. And then, as a civilization, we tend make a huge leap, arriving at what has largely become an article of faith: we will transition to these renewables as the basis of our future civilization.
How will we prioritize this transition among competing economic desires? How will we pay for it, both in terms of financing and the up-front energy cost of most renewables? How do our assumptions about the availability of fossil fuels going forward affect this transition? Does renewable energy technology provide sufficient net-energy returns to make this transition practical? How will this transition be organized and implemented?
There are many answers to these (often unasked) questions: the market will take care of it, government subsidies and incentives will pave the path, technology will improve, etc. These are all fine theories, but it is important that we must recognize them as exactly that: possible, not certain, outcomes. The purpose of this series is to examine the actual process of transition. Specifically, I hope to take a system-wide perspective to identify systemic choke-points and externalities that may result from efforts to take existing renewable energy programs and technologies—currently comprising only a very small portion of our civilization’s energy production—and scale them up to meet the majority of our global energy needs.
One focus will be on the systemic impacts and cascading effects of one simple reality: renewable energy sources tend to require an up-front investment of energy, and then pay-back that investment (plus, hopefully, a significant surplus) over a period of time.
The simple fact of the matter is that renewables, much more so than most fossil-fuel based modes of energy production, require primarily up-front investment (of both money and energy—to the extent that we should consider there to be any real difference between the two).
So what? Here’s the quick outline of why this matters: We are currently in a climate of energy scarcity, and this will likely get worse in the future. If you want to increase the amount of energy derived from renewable sources (and thereby help to ameliorate the energy scarcity), you need to first exacerbate that scarcity to use some of our available energy as an up-front investment in these new renewables.
It's also worth addressing one concern raised previously on this point by readers: the difference between electricity generation and the overall energy requirements of our civilization. Right now, electricity is only a portion of the total energy consumed by our civilization. And of that portion, the majority is generated by burning fossil fuels like coal, and, arguably, nuclear. However, the renewables that are generally seen as the key to our society's energy transition (solar, wind, tidal, geothermal) all produce electricity. This electricity can be used to substitute for liquid fuels consumption (either directly through electric motors and heating or indirectly through conversion to hydrogen, etc.). In a post-peak fossil fuel scenario, a continuation of our society's energy consumption can only be maintained by substituting for the declining production of fossil fuels (first oil, then gas, then coal and fissile-materials used in nuclear energy, probably roughly in that order). Shortfalls in fossil fuel production can be substituted with electricity (or a derivative such as hydrogen) or biofuels.
Biofuels have demonstrated very poor EROEI, have a nasty habit to conflict with food production, are highly susceptible to weather changes (whether or not caused by global warming), and appear highly dependent on soil fertility that is currently maintained by massive inputs of iNPK fertilizers that will themselves become a serious resource constraint in the future. The prospects for transitioning the majority of global energy use to a "sustainable" biofuels foundation are, in my opinion, unlikely at best, catastrophic at worst. However, I will address this option toward the end of this series.
Renewable electricity generation, however, shows more promise, at least superficially. Most serious policy discussions, environmental groups, and viridians (what's I've elsewhere called "Roddenberrys"--those who think the continuation of our current civilizational trajectory is possible through green technology) are counting on the use of renewable electricity generation to 1) replace fossil fuel derived electricity, and 2) provide a renewable, green source of energy to substitute for increasing portions of all other current energy consumption (e.g. liquid fuels). My main focus will be on examining the practicality of this path.
So, returning to the question posed above, because of the up-front investment required by renewable energy options, if you want to increase the amount of energy derived from renewable sources (and thereby help to ameliorate the energy scarcity), you need to first exacerbate that scarcity to use some of our available energy as an up-front investment in these new renewables. How much such investment, how much exacerbation of current energy scarcity, is practical? Whether or not this amount of additional energy draw is practical is largely a factor of how much is needed to affect any significant degree of transition within the necessary timeframe (e.g. to keep pace with fossil fuel decline rates). How much up-front energy investment is needed, I will show, is a factor of the true EROEI of these renewable technologies and the mechanics of net-energy scalability. Those will be the topics of the next several posts in this series...