Did you know? The heat in the upper six miles of the earth’s crust contains 50,000 times much as energy as found in all the world’s oil and gas reserves combined. Despite this abundance, only 10,500 megawatts of geothermal generating capacity have been harnessed worldwide. For more information view the text and data in Chapter 5 of Plan B 4.0: Mobilizing to Save Civilization.
Chapter 7. Stabilizing Climate: Raising Energy Efficiency
If rising temperatures continue to shrink harvests and begin driving up food prices, public pressure to stabilize climate by cutting the carbon emissions that cause the greenhouse effect could become intense. The goal is to cut these emissions enough to stabilize climate and eliminate the threat to world food security from rising temperatures. Cutting emissions enough to stabilize atmospheric CO2 levels is an ambitious undertaking, but given the technologies now available to both raise energy efficiency and develop renewable sources of energy, it can be done—and quickly, if need be.
This is not the place to lay out a detailed global plan to cut carbon emissions, but a few examples of how to cut the use of oil and coal, the principal sources of carbon emissions, will illustrate the possibilities. One simple step that motorists can take to reduce oil use dramatically is to shift to cars with hybrid gas-electric engines. Automobiles such as the Toyota Prius and the hybrid Honda Civic that are already on the market are remarkably fuel-efficient. The 2004 Prius averages 55 miles per gallon in combined city and highway driving—double or even triple that of other midsize cars. If the United States were to raise the fuel efficiency of its automobile fleet over the next 10 years to that of today’s Toyota Prius, U.S. gasoline consumption could be cut in half. This would not require any reduction in the number of cars used or in miles driven, only the use of more-efficient engines. 26
But this is not the end. The hybrid gas-electric cars, which embody the most sophisticated automotive engineering on the road today, open up two exciting additional possibilities. The first is to modestly expand the electrical storage capacity of the hybrids by adding a second battery. The second is to include a plug-in recharge capacity so that owners can recharge their car batteries at night, when electricity demand drops, leaving surplus generating capacity. Given the typical U.S. daily commute of 12 miles roundtrip, these two steps would allow commuting and local driving, such as shopping, to be done almost entirely with electricity, saving gasoline for the occasional longer trip. Adding a second battery and a plug-in capacity could reduce gasoline use by perhaps another 20 percent, for a total reduction in U.S. gas use of 70 percent. 27
These two modest technological modifications lead to an exciting possibility on the supply side, namely the use of cheap wind-generated electricity to power automobiles. Does the United States have the wind power potential to do this? As described later in this chapter, it has enough harnessable wind power to meet its electricity needs several times over. 28
There are similarly exciting possibilities for cutting coal use. If, for example, the world were besieged by high temperatures and rising food prices, it would be a simple matter to replace the widely used old-fashioned, highly inefficient, incandescent light bulbs with compact fluorescent lamps that provide the same light but use less than a third as much electricity. A worldwide decision to phase out incandescent light bulbs would allow literally hundreds of coal-fired power plants to be closed. Not only would this help stabilize climate, but the return on investment in the new bulbs in the form of lower electricity bills is roughly 30 percent a year. 29
These are but two of the obvious things that can be done on the demand side to cut carbon emissions. Reducing U.S. gasoline use for automobiles by 70 percent and dramatically cutting electricity use for lighting are exciting prospects for reducing dependence on imported oil, lowering the trade deficit, and stabilizing climate. We simply need a bit of imagination, some leadership, and a modest additional investment.
26. U.S. Department of Energy and Environmental Protection Agency, Fuel Economy Guide (Washington, DC: 2004); gasoline savings based on Malcolm A. Weiss et al., Comparative Assessment of Fuel Cell Cars (Cambridge, MA: Massachusetts Institute of Technology, 2003).
27. U.S. Department of Transportation, Bureau of Transportation Statistics, Transportation Statistics Annual Report (Washington, DC: October 2003), p. 52.
28. D. L. Elliott, L. L. Wendell, and G. L. Gower, An Assessment of the Available Windy Land Area and Wind Energy Potential in the Contiguous United States (Richland, WA: Pacific Northwest Laboratory, 1991); C. L Archer, and M. Z. Jacobson, “The Spatial and Temporal Distributions of U.S. Winds and Wind Power at 80 m Derived From Measurements,” Journal of Geophysical Research, 16 May 2003.
29. Howard Geller, Compact Fluorescent Lighting, American Council for an Energy Efficient Economy Technology Brief, at www.aceee.org, viewed 17 September 2004.
Copyright © 2004 Earth Policy Institute