Friday, August 28, 2009

Recent Nature Conservancy Study Looks at Clean Energy Sprawl

Should Hawaii reconsider its energy policy, which seems to focus on biomass and ethanol? Has there been a critical assessment of how particular alternative energy solutions will impact Hawaii's environment?

In a recent article by the Nature Conservancy--McDonald RI, Fargione J, Kiesecker J, Miller WM, Powell J, Energy Sprawl or Energy Efficiency: Climate Policy Impacts on Natural Habitat for the United States of America, August 26, 2009--the authors investigate land-use impacts to U.S. habitat types of new energy development resulting from different U.S. energy policies. Also referred to by the authors as, "the habitat impact of future energy sprawl." Id. at 1.

The study found that biodiesel from soy had 20 times the impact of petroleum on land-use intensity for energy production. See Id. at Fig. 3, p. 4. In addition, the impacts of the following compared to petroleum are:
  • electricity from biomass, 12.2 times
  • ethanol from cellulose, 10.2 times
  • ethanol from corn, 7.8 times
  • ethanol from sugarcane, 6.4 times
  • wind, 1.6 times
  • hydro-power, 1.2 times
The impact from solar photovoltaic, natural gas, solar thermal, coal, geothermal, and nuclear power all have less of an impact than petroleum. Id.

The impact on land may be compounded by indirect and secondary impacts, which the authors discussed as follows:
Energy crop production is a particularly complex situation because even if new energy crop production occurs on land that was previously in agricultural production, remaining global demand for agricultural commodities may spur indirect effects on land-use elsewhere, potentially causing an agricultural expansion in areas far from the location of energy crop production. Other energy production techniques have a relatively small infrastructure footprint and a larger area impacted by habitat fragmentation and other secondary effects on wildlife. A review of the literature found that production techniques that involve wells like geothermal, natural gas, and petroleum have about 5% of their impact area affected by direct clearing while 95% of their impact area is from fragmenting habitats and species avoidance behavior. Wind turbines have a similar figure of about 3–5% of their impact area affected by direct clearing while 95–97% of their impact area is from fragmenting habitats, species avoidance behavior, and issues of bird and bat mortality. Id.
The study suggests four ways to achieve emissions reduction while avoiding energy sprawl: (1) energy conservation to reduce the new energy needed by the U.S.; (2) policy that encourages end-use generation of energy; (3) a flexible cap-and-trade bill allowing for carbon capture and storage at coal plants, new nuclear plants, and international offsets; and (4) appropriate site selection and planning for energy development, e.g., siting in already disturbed places. Id. at 6.

For more on energy issues, see Energy.

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