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How Far Energy Efficiency ?

Analysts agree about the need for developing both new and cleaner energy resources. At the same time, some argue that energy efficiency can provide only a minimal role in meeting future energy needs. Hence, energy supply is encouraged while energy efficiency is supported only minimally. Analysts Douglas Lightfoot and Christopher Green suggest in a series of papers, for example, that there are practical limits that will constrain the rate of efficiency improvement to no more than about one percent per annum over the next 100 years. This paper explores the assumptions that underpin such “practical limits” and concludes that efficiency gains perhaps could more than double the rate suggested by Lightfoot and Green. The question is not one of practical limits; rather, the issue is one of choosing to develop energy paths that allow greater system efficiencies to emerge.