Renewable energy zealots must understand ‘Net Energy'
Was I surprised that last issue’s column, Can Renewables Outshine Fossil Fuels?, elicited a strong reaction, with written responses of support and derision? Not at all. It’s an issue that continues to divide the environmental community, and one which keeps us from moving forward as quickly as possible to conserve resources and relocalize as an era of cheap, concentrated, easy-to-get energy comes to an end.
My essential argument is that we need to use fast-depleting fossil fuels to create a renewable energy infrastructure even while understanding that renewable energy sources, as some energy researchers are realizing, cannot come close to replacing fossil fuels to meet current energy demand. Moreover, renewables, coupled with massive energy curtailment, will not any time soon become our primary energy source, largely because of various limiting factors, including resource constraints and possible prolonged world economic depression as the debt-based money system unravels.
My critics fail to understand the concept of “net energy,” a full accounting of the energy inputs required to produce a given unit of energy. Renewable energy requires far more imputs of energy, materials and money than do fossil fuels per equivalent unit of energy produced, recent research shows. Especially challenging will be finding a liquid fuel and feedstock alternative to oil, which powers close to 100 percent of global transportation and is ubiquitous in consumer products. No other fuel is as energy-dense, versatile, easily-transportable and abundant as oil. It is the main fuel powering a globalized industrialized civilization and will do so just once.
Here’s my response to some critics’ specific arguments:
Case Western Reserve University physics professor Philip Taylor suggests we “need gather only one part in 2,000” of the sunlight falling upon the earth’s land area to meet our energy needs. While these back-of-the-envelope calculations are presented as veritable proof of solar energy’s availability, a difficult reality emerges. For constructing, installing and maintaining the devices to capture this abundant but diffuse energy is a massive, expensive, fossil-fuel consuming undertaking requiring the mining of finite and ever-scarcer rare-earth minerals and other materials and accruing tremendous human, energy and environmental costs. Yes, we might need to gather only 1 part in 2,000 at current demand. The challenge is doing so in a world with increasing population and declining net energy—with more energy increasingly expended to produce the same amount of useful energy—while fossil fuel production peaks and heads toward collapse, and resource wars intensify.
Taylor also contends that solar cells can be as much as 40 percent efficient, much higher than plants. He misses the forest for the trees when he only looks at end-use efficiency rather than lifecycle efficiency. Is a solar panel really more efficient at capturing sunlight than a tree, considering all of the water and finite fossil fuels used and toxic waste created during its production? A self-replicating tree only requires inputs provided by its immediate environment and is 100 percent recyclable.
Cleveland-area environmentalist Glenn Campbell offered “almost certain technological breakthroughs,” including ones “we can’t foresee today” as evidence that renewables will take care of our energy needs, as if technology itself was the energy source. In fact, technological development has accelerated our energy extraction and use. Even when it’s designed to increase efficiency, it still grows overall energy use (known as Jevons’ paradox). Thus, the more efficient we become, the more we consume. And increasing consumption is our biggest enemy, although it is required for the economic growth needed to try to keep the compounding debt-money system from collapsing.
While rushing to meet current demands with renewables, we should first ask ourselves why we need so much energy in the first place and figure out what can we do better with far less energy. My suggestion is that we reduce our wasteful consumption of energy while we invest our remaining fossil fuels largely in installing decentralized, small-scale renewable technologies that communities can replicate and control. This should be part of a larger integrated initiative to, among other things, relocalize food production, retrofit existing housing stock and establish decentralized systems of zero-interest credit to help businesses, create jobs and stimulate local exchange of goods and services.
These types of measures are critical to addressing our dangerous dependence on those who control the supply and distribution of energy, food, credit and other vital systems—even as we are disempowered through neoliberal globalization to take care of ourselves and our communities. So solar, wind, geothermal and other renewable energy technologies should be viewed as part of a larger vision to create energy-conserving and sustainable local communities. But renewable energy’s limits, compared to fossil fuels, must be understood and its potential contributions not exaggerated.
My problem therefore is not with renewables, but with renewable energy zealots who make pie-in-the-sky calculations that placate policymakers and the public and promote apathy. It’s easier to let some scientists and engineers try to figure out our energy problem for us while we turn up the air conditioning in our 3,000-square-foot homes or drive gas-guzzling SUVs, when it is this very unsustainable lifestyle that is the root of our environmental problems, not fossil fuels.
Renewables won’t save us. We have to save ourselves.
What do you think? Leave a comment below.
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