Renewable energy is often touted as the future because it has lower CO2 emissions or “can solve our energy scarcity problems because it will replace oil”. Unfortunately, renewable energy is far from solving those massive problems. Solar, wind, geothermal, tidal, etc… all require tremendous amounts of oil to get their infrastructure up and running, emitting CO2 in the process. However, I’ve lost interest in the climate change problem because it is just a subset of an industrial society that’s completely dependent on high net energy production of oil, so I’ll just focus on energy scarcity for now.

I’ve been really impressed Jeff Vail’s analysis of this renewable energy problem I’ve alluded to above. In this November 9th recap of his 2009 APSO presentation, Jeff defines the “Renewables Gap” and presents some startling numbers.

I’m working on renewable energy technology in my graduate school program at University of British Columbia but seeing the resources required for production of high-tech energy solutions is disconcerting. The amount of energy required to run the microscopes, testing equipment, and chemical synthesis of materials may not be possible in a world of energy scarcity. Energy innovation may come to a halt because we can’t afford to devote energy to it in a decade or so. Realizing that this is a possible outcome, we’ll need to use current technology when defining the Renewables Gap.

To develop a renewable infrastructure that continues with the infinite growth paradigm using current technologies may be impossible. Jeff Vail determines that, “between 80% and 90% of the total energy ever required to build, operate, and maintain these systems must be invested up front.”

Additionally, Jeff reminds us that, “these renewables produce ELECTRICITY, not oil. We’re talking here about using them to replace oil—let’s talk about conversion issues. How many GWh are needed to replace 1 mbpd of oil production? A straight BTU-to-BTU conversion: replacing 1 million barrels of oil per day production, or 365 million barrels of oil per year, equates to 70.78 Giga-Watt-Years. Clearly, however, oil and electricity are not the same thing.”

Jeff also draws on the fact that quickly ramping up renewable production also requires a significant investment in our transmission grid. I’ll focus on solar energy because that’s what I’m familiar with from the utility industry but all forms of renewable energy production face similar challenges. Solar power sounds like a great idea until you realize that the sun goes down at night and that cloud cover produces a very spotty generation profile. If clouds frequently cover the sun, the energy passed on to the grid can swing back and forth dramatically, ruining the precision engineering balances on power factor and other variables that keep our lights from going off. Mass deployment of solar photovoltaics, requires mass deployment of large-scale storage that can smooth these voltage swings, preventing damage on local transformers. Unfortunately, while the cost of photovoltaic modules has decreased over the last decade, cost effective utility scale storage is far from ready for mass deployment.

Jeff investigates the amount of oil we’ll need to invest in renewables to offset oil production rate decline in two varying scenarios. The two scenarios being an optimistic 5% rate of annual oil production decline and a more realistic 10% rate of annual oil production decline. I’ll quote the numbers he uses for a 5% decline rate because the numbers for a 10% decline rate are quite scary.

“In this [5% annual decline] scenario, to mitigate the year-1 decline in net energy from oil, we’d need to invest 467 GWy of energy in year one without any production in return—that’s the equivalent of almost 7 million barrels per day. Then in year two it’s about 130 GWy more invested than cumulative production to that point, or about a 2 million barrel per day deficit. Not until year-three will the cumulative renewable generation be more than the investment deficit for that year—meaning that not until year 3 will we begin to have surplus energy available to mitigate the actual decline in oil production (which by this point leaves us 12 million barrels per day behind the peak oil decline curve.” That’s the “Renewables Gap.”

I’m skeptical that our society would be willing to invest that much energy in renewable infrastructure growth. Quite simply, our global system has outgrown the energy available to maintain it. This means that, as Gail Tverberg concludes in his recent essay for The Oil Drum,

Efficiency and Smart Growth are “Brain” technologies, as opposed to the “Brawn” of traditional and new energy sources. As such, their application requires long-term planning and thought. Cheap energy has led to a culture where we prefer to solve problems by simply applying more brawn. As our fossil fuel brawn fades away, we will have to rely on our brains once again if we hope to maintain anything like our current level of economic activity.

“Green” energy is also highly land intensive. Some of the most cost effective options for reducing our dependence on fossil fuels are also highly land intensive. A recent article on The Enterprise Irregulars covers the issue of the coming Green Sprawl which will devastate the carrying capacity of our ecosystem to support humans. CO2 emission reduction strategies will likely take us down the road of tearing up the prime farm land we’ll need to survive an energy crisis.

I’m currently focusing on the brawn solutions and we’ll see where that takes me over the next few years. However, as things start to unravel, I’m preparing to focus my research on the brain solutions Tverberg advocates. I’ll hope the global society we’ve built can pick up on that trend before things would become too dire for policy to make a difference.