Toward More Efficient Global Warming Policy Solutions: The Necessity for Multi-Criteria Selection of Energy Sources

Despite humans' acknowledgement of the main drivers of global warming, greenhouse gas (GHG) emissions are still increasing dramatically worldwide. GHG emissions in the U.S. have increased by 17% during the 1990-2009 period and are expected to increase even more with the economic growth after the current recession. Although current dominant policy for combating global warming relies on substitution of fossil energy sources with the renewable ones, we argue that such a general policy may be inefficient. In fact, such a policy is only a short-fix solution to the problem and may be associated with unintended consequences or secondary effects on other sectors and valuable natural resources. This paper highlights the necessity of multi-criteria decision analysis to select energy sources which are not only efficient in terms of GHG emissions reduction, but also will have minimal adverse effects on other sectors and resources. By simultaneous consideration of performances of energy sources under different sustainability criteria, it is discussed why some renewable energy sources may be even less promising than some nonrenewable energy sources in reducing GHG emissions without affecting other resources and violating the sustainability rationales. The three considered sustainability criteria in this study include carbon footprint, water footprint, and cost, reflecting the environmental efficiency, water use efficiency, and economic efficiency, respectively. The performances of a range of non-renewable and renewable energy sources are considered under the three sustainability criteria to rank the energy sources based on different social choice rules with respect to the uncertainty involved in estimating the performances.