Alternative Energy Sources and Land Use
Clinton J. Andrews, Lisa Dewey-Mattia, Judd M. Schechtman, and Mathias Mayr project that, by 2030, the global demand for energy will increase from the 2010 level of about 149,000 terrawatthours per year (TWh-yr) to about 199,000 TWh-yr. Generating the additional electricity to meet this demand by burning fossil fuels will increase CO2 emissions. Hence, considerable attention has been paid to the development of renewable energy sources of electricity. The authors analyze how the adoption of renewable energy and the expansion of the associated infrastructures may affect land use. They compare conventional and alternative energy sources and divide them into three categories based on land intensity, which is defined as land area (km2) required for delivering 1 TWh-yr. Category I comprises nuclear power, geothermal, coal, solar thermal, and natural gas. These sources are not land intensive, but only two of them are renewable. Geothermal energy, which uses gas- and oil-drilling technology to harvest underground hot water, is not available in all locations. Similarly, high-temperature solar power plants must be located in areas where sunlight is abundant. Delivering electricity generated by these renewable sources in remote locations to consumers is unlikely to be cost-effective.
Category II includes solar photovoltaics, petroleum, hydropower, and wind. These sources require large tracts of land when implemented on a large scale. Rooftop solar panels may allow energy self-sufficiency only in sunny places and for single-story houses built with highly energy-efficient technology. Using photovoltaics in urban areas where buildings are often more than two stories high and do not have sufficient roof area is unlikely, the authors argue. Large-scale solar and wind farms may have to be located in remote areas where resources (land, sun, and wind) are available and where siting conflict is minimal. Category III is the most land-intensive category and includes all biofuels. A primary concern about biofuels is their potential for displacing food production and forests from current arable lands. The authors assert that biofuels are unlikely to become an important energy source.
Because most renewable energy sources may have to locate away from cities, where energy demand is concentrated, transmission becomes an issue. Although transmission lines are not land intensive or expensive, their siting faces numerous institutional constraints, including misalignment of incentives to encourage the construction of new transmission lines, lack of review standards for permit applications, technical challenges associated with the intermittency of renewable energy, and opposition from landscape protection groups. These constraints make siting of power facilities and transmission lines, not land intensity, a key barrier to the development of renewable energy sources.
This paper was presented at the Lincoln Institute’s Land Policy Conference of 2010 and is Chapter 5 of the book Climate Change and Land Policies.
