Environmental Problems, Their Causes, and Sustainability 1

18 andEnergy EfficiencyRenewable EnergyEnergyCASE STUDYThe Coming Energy-Efficiencyand Renewable-EnergyRevolutionEnergy analyst Amory Lovins built a large, solarheated, superinsulated, partially earth-sheltered homeand office in Snowmass, Colorado (Figure 18-1), withseverely cold winter temperatures.This structure also houses the research center forthe Rocky Mountain Institute (cofounded in 1982 byAmory and Hunter Lovins), an office used by 45 people.This office–home gets 99% of its space and waterheating and 95% of its daytime lighting from the sun,and uses one-tenth the usual amount of electricity fora structure of its size.With today’s superinsulating windows a housecan have many windows without much heat loss incold weather or heat gain in hot weather. Thinner insulationnow being developed will allow roofs andwalls to be insulated far better than in today’s bestsuperinsulated houses.A small but growing number of people in developedand developing countries get their electricityfrom solar cells that convert sunlight directly into electricity.They can be attached like shingles to a roof,used as roofing, or applied to window glass as a coating.Solar-cell prices are high but falling.According to many scientists and executives ofoil and automobile companies, we are in the beginningstages of a hydrogen revolution to be phased induring this century as the Age of Oil (Appendix 5)begins winding down (Figure 17-6, p. 353). Becausethere is little hydrogen gas (H 2 )around, we have touse another energy resource to produce it fromwater or various organic compounds such asmethane. We could do this by passing electricityproduced by renewable energy from wind turbines,hydroelectric power plants, solar cells, biomass, andgeothermal energy from the earth’s interior throughwater to make H 2 gas. Energy-efficient fuel cellscould use the hydrogen to produce electricity to runcars and appliances, heat water, and heat and coolbuildings.Burning hydrogen in a fuel cell by combining itwith oxygen produces water vapor and no carbondioxide. Thus shifting to hydrogen as our primarysource of energy would eliminate most air pollutionand also greatly slow global warming—as long as thehydrogen is produced from water and not carboncontainingfossil fuels and the nuclear fuel cycle thatemit the greenhouse gas CO 2 into the atmosphere.Robert Millman/Rocky Mountain InstituteFigure 18-1 The RockyMountain Institute inColorado. This facility is ahome and a center for thestudy of energy efficiencyand sustainable use of energyand other resources.It is also an example of energy-efficientpassive solardesign.