York’s quantitative modelling challenges the common assumption of the Intergovernmental Panel on Climate Change and many energy analysts that each unit of energy supplied by alternative and renewable resources takes the place of a unit of energy from fossil fuels. Instead, York finds that the average pattern across the world is one where each unit of alternative and renewable energy displaces less than one-quarter of a unit from fossil fuels. And that is energy as a whole; for electricity specifically, the proportion is as little as one-tenth of a unit.
In technical terms, York looks at the principal driving forces of per capita demand for fossil-fuel energy, and the amount of energy provided by hydropower, nuclear, geothermal, solar, wind, ocean tidal and wave, and combustible renewables. He then tabulates the displacement coefficients which relate fossil-fuel and alternative energy sources.
What York’s data show is that, even allowing for a non-linear relationship between economic activity and energy use, replacing a single kilowatt-hour of fossil-fuel electricity requires the generation of more than 11 kilowatt-hours of alternative or renewable electricity. A second model incorporates sociological and epidemiological factors such as urbanisation and demographics, and comes to the same conclusion.
Given these results, the common assumption that an expansion of alternative energy production will suppress fossil fuels is clearly wrong. This does not necessarily mean that alternative energy will be of little use in moving to a post-carbon world, but we must avoid seeing the shift away from fossil fuels as inevitable with the expansion of alternative energy sources.
In his concluding remarks, York says that the direct suppression of fossil-fuels through carbon taxes is likely to be much more effective at reducing their use than simply expanding alternative energy sources. In that case, political will and action becomes more important than technology and market-centred energy planning…
“The most effective strategy for curbing carbon emissions is likely to be one that aims to not only develop non-fossil energy sources, but also to find ways to alter political and economic contexts so that fossil-fuel energy is more easily displaced and to curtail the growth in energy consumption as much as possible. A general implication of these findings is that polices aimed at addressing global climate change should not focus principally on developing technological fixes, but should also take into account human behaviour in the context of political, economic and social systems.”
This is probably the last thing that industrialists and policymakers want to hear, but, along with the data that back up York’s argument, it cannot be ignored.