What energy source is noisy, a visual blight on the pristine countryside, taxpayer and ratepayer subsidized, a hazard to birds (including endangered species), the subject of a $100 million cleanup/​restoration operation in California and two to three times more costly to produce than an identical substitute? If you guessed wind generation of electricity, you are correct.

What energy source requires over 100 times the space of conventional electric power plants, is located in pristine desert areas, is taxpayer and ratepayer subsidized, and produces the most expensive electricity on earth at twice the cost of nuclear power? If you guessed solar farm generation of electricity, you are also correct.

Despite economic and environmental problems, wind and solar power are being touted by the Clinton administration as the two key sustainable energy sources to address the alleged problem of global warming. Abundant natural gas, the cheapest and cleanest of the fossil fuels for generating electricity, is welcomed only as a “bridge fuel” to sustainability. Oil, coal and nuclear energy are out — as is the politically incorrect renewable, hydroelectricity.

The attraction of wind and solar energy is peculiar from just about any viewpoint. If the environmentalists’ primary concern is air emissions, nuclear power and hydroelectricity would seem to be the fuels of choice. Those air-emission-free sources of energy account for over 30 percent of U.S. electricity output, compared with the one-tenth of 1 percent output of wind and solar combined. Nuclear and hydroelectric energy, in fact, were once supported by mainstream environmentalists for their displacement of air emissions. Now, leading environmental organizations such as the Natural Resource Defense Council, the Environmental Defense Fund and Greenpeace want to close down nuclear plants, dismantle dams producing hydroelectricity to return rivers to their natural state and block construction of new hydro and nuclear facilities.

Two other renewable sources of energy, while nominally politically correct, are less preferred than wind and solar. Biomass produces air emissions from the burning of wood and other waste products — a defect that is hard to overlook. New commercial geothermal sites are typically in protected land areas and opposed by environmentalists.

If hydropower is not invited to the sustainable energy ball, how can wind power remain on the guest list? Bird kills in California led a Sierra Club representative to label wind turbines the “Cuisinarts of the air,” while the National Audubon Society has called for a moratorium on new wind projects in bird-sensitive areas. The documented killing of radio-tagged golden eagles, a felony under state and federal law, has gone unprosecuted by authorities and unreported by the national media. A California Energy Commission study’s “conservative” estimate of 39 golden eagle deaths per year at the Altamont wind farm suggests a cumulative problem worse than the eagle deaths from the Exxon Valdez oil spill.

Despite environmental problems, wind and solar farms are touted as having one advantage over fossil-fuel plants-no air emissions. Yet even that claim is exaggerated. A major reason wind and solar generation is so expensive despite having free energy inputs is that the needed infrastructure requires more materials than are used in fossil-fuel plants. More concrete, steel and glass mean more energy consumed to manufacture those energy-intensive inputs, which means more air pollution. So, ironically, the construction of new wind and solar farms worsens air pollution in the short run.

The so-called embedded fuel problem leaves but one answer for the environmentalists: generating from renewables the electricity needed for the manufacture of wind and solar farms. Leaving aside the fact that the circle has to start with conventional fuels, the higher cost of renewable energy would make the construction of new renewable energy plants even more cost prohibitive than it is today. Falling fossil-fuel prices since the 1970s have reduced the cost of producing renewable energy; any restrictions on conventional electricity from a global warming treaty will worsen the plight of already uneconomic renewables.

Two decades and billions of dollars of effort by state and federal energy programs to commercialize wind and solar can be pronounced a bust. Only renewable quotas in two states (Iowa and Minnesota) and a $540 million renewable bailout enacted last year in California are keeping the failure afloat. Yet the federal government is now considering a renewables mandate for all 50 states as part of a laudable effort to competitively restructure the nation’s electricity industry. Not only consumers and taxpayers but sophisticated environmentalists as well should revolt at the prospect of renewable mandates. Truly sustainable energy is affordable energy free of unintended environmental consequences.