The U.S. is facing energy challenges that can only get worse. As global demand continues, readily accessible oil and gas deposits dwindle, competition for world supply accelerates, and costs rise, it is clear that we must develop and exploit alternatives.

In response, companies are rushing to “green-up” their investment portfolios, business plans, advertising images, and lobbying strategies, cheered on by a hopeful public and its representatives. After all, who can resist the allure of cleaner, perpetually sustainable, unlimited new supplies of power and fuel that will provide independence from foreign sources? Yet upon closer scrutiny, many are beginning to realize that green expectations are oversold. Increasing critics are challenging the actual benefits of various choices, including a growing number of consumers and more than a few environmental groups.

Alternative (a.k.a. “green”) energy initiatives are receiving expanding levels of support from federal, state, and local incentive programs. Tens of billions of dollars have been provided through subsidies, production credits, accelerated depreciation tax credits, and public funding for research.

The federal Energy Policy Act of 2005 mandated a biofuels phase-in, starting at 4 billion gallons in 2006 and reaching 7.5 billion gallons by 2012. In December 2007, the House of Representatives passed an energy bill that would have required all investor-owned utilities (but not municipal systems and rural cooperatives) to obtain 2.75 percent of their electricity from renewables by 2010, and 15 percent by 2020. The Senate rejected the provision, which would transfer wealth from already-distressed electricity consumers to a heavily subsidized wind power industry. But numerous states are requiring utilities to invest in renewables. As of February 2008, 25 states and the District of Columbia had instituted mandatory Renewable Portfolio Standards that set timetables for increasing percentages of legislated “green” energy. However, the majority of their government-owned utilities have successfully lobbied for reprieves from the costly and often unrealistic requirements.

In addition to its currently uncompetitive costs, relative to coal, natural gas, and nuclear for electricity and oil for transportation, a major and long-term problem for the green-energy industry is its limited practical expansion capacity. Consider that alternatives presently account for only about 6 percent of the total U.S. electrical power production (half of that from hydropower). Wind power (about 0.77 percent of the total) is the only alternative prospect for significant growth, and it has a long way to go in replacing fossils (about 71 percent) and nuclear (about 8 percent of the total, and about 19 percent of electricity). On the basis of cost and capacity, solar power (about 0.07 percent of the total, and 0.01 percent of electricity), is not a contender for a significant commercial market share. Geothermal expansion is even more economically and geographically restricted.

In reducing dependence on coal and natural gas for heating and on petroleum for transportation, biofuels are proving less advantageous than the public anticipated. Corn ethanol yields little more energy than required to produce it, and puts food demand in direct competition with motor fuel demand. Much-touted cellulosic ethanol from plant waste is not yet a commercial reality, and the term “hydrogen economy” is an oxymoron. Hydrogen requires much more energy to produce than it yields, and its primary commercial source is natural gas, which has more efficient and beneficial uses. Of course hydrogen can also be produced from water – assuming that cheap and abundant energy is available from another source to electrolyze the water and compress or liquefy the gas. A gallon of gasoline actually contains about 50 percent more hydrogen than a gallon of liquid hydrogen.

But just how “green” are these alternatives? Over time, fossil and nuclear energy may look somewhat less objectionable to many environmentalists. And perhaps others are simply more united in their opposition to “brown power” than in their support for mischaracterized green power options.

Geothermal sites capable of producing electrical power are geographically limited. Located primarily in the western half of the U.S., many are in protected federal parks and natural wilderness areas that are not open for development. Heat extraction for power is expensive, often necessitating drilling a mile or more underground and requiring extensive infrastructure and power lines along with large amounts of cooling water. Processes often release groundwater contaminates (thermal and toxic), gas emissions (hydrogen sulfide), and mineral-rich sludges containing mercury and other heavy metals.

Hydropower dams are unpopular with conservationists because they disrupt river ecosystems, hampering or preventing migrations of some fish species such as salmon. They can cause vegetation to decay along riverbeds, releasing large amounts of methane when the dams are built, and rapid water releases can kill fish, plants, and wildlife downstream. Very few unrestricted sites are available for major new systems.

Solar power is probably the least environmentally objectionable alternative, but is not practical in many regions that have frequent cloudy, rainy, dusty, or snowy days. It is also expensive, presently costing many times more than fossil energy.

Biomass burning, which provides nearly half of all U.S. renewable electrical power, demands large amounts of land that might otherwise be wooded or dedicated to food crops. It also releases carbon dioxide.

Although nuclear power is not typically characterized as such, it is the only alternative energy source that offers substantial expansion potential beyond its current contribution. Even though plants emit only water vapor, radioactive waste containment and releases due to accidents or terrorism are issues of public concern. Safety records at nuclear facilities have been excellent, and technology advancements are further reducing risks and potential consequences. Waste problems could be reduced by recycling spent materials using breeder reactors, but this was outlawed during the Carter Administration due to concerns about proliferation of weapons-grade fuel that might fall into enemy hands.

It is essential to our national and global future that development and utilization of alternative energy continue. This includes improvement and expansion of nuclear power and innovations to produce cleaner energy from coal and other fossil sources for which there is no practical substitute.

Proposed carbon emission cap-and-trade legislation predicated on global warming hysteria and the demonization of carbon dioxide will solve nothing. It will only constrain new power plant development, making energy – and other consumer goods – more expensive. Although resulting shortages and price escalations may eventually promote support for nuclear power expansion, permitting and development of those vital plant infrastructures must begin immediately to keep the lights burning.

If any green will be realized through carbon trading, it will primarily move from consumers’ pockets (due to increased power, fuel, and product costs) to the bank accounts of hedge fund speculators and subsidy recipients. Let our current ethanol experiences be a lesson.