Environmentalists of all stripes support policies to expand solar energy and wind energy, among other “renewables.” Indeed, solar and wind are viewed across the spectrum of environmental groups as a principal method for reducing carbon dioxide emissions and other greenhouse gas emissions that are causing increasingly catastrophic climate change. Fossil fuels are the main sources of such climate change.

Here’s the bright picture. Efforts to curb greenhouse emissions are spreading. In the U.S., many environmentalists have urged the federal government to continue or increase its support of solar and wind energy by expanding subsidies to these sectors or, when appropriate, by putting solar panels, and wind generators on or near federal buildings and military facilities, and by increasing the fuel efficiency of the federal government’s fleet of cars and other vehicles. They are sometimes successful. The Army and Navy are moving ahead on the clean energy front. Some states have also played a part, requiring electric utilities to increase solar and wind as a proportion of their total electric output. And Bill McKibben writes that there has been growing “resistance” in opposition to some of the most egregious manifestations of fossil fuel operations - e.g., fracking, tarsand pipelines, mountaintop removal- as well as against fossil fuels in their entirety. Other countries have also expanded their use of solar and wind energy, including, for example, Germany, Norway, the Netherlands, China.

Despite these growing efforts, however, there has not been enough change to stop CO2 concentrations from rising in the earth’s atmosphere. The most recent record indicates that CO2 concentrations have now reached 400 ppm, up from 317 ppm in 1958, and up from under 280-290 ppm at the start of industrialization in the 19th century. Some scientists expect that the concentration will reach 450 ppm in two or three decades. The earth’s average temperature rises along with rising CO2 concentrations, and the rising temperature have a multitude of disruptive environmental effects, from the melting of ice in the Arctic, Greenland, and glaciers across the earth, to warming of the oceans, to a host of severe weather events, to a growing number of environmental refugees, and so forth.

Here are some recent titles of articles on the internet that capture some of the dire trends: “Carbon’s Climb Speeds Up,” “New research shows global warming speeding up,” “Climate change even worse than we feared,” “2012 hottest year since record keeping began in 1895,” “No reprieve from the heat – China high temperatures tied to greenhouse gases.”

Most environmentalists would agree that fossil fuels and other sources of greenhouse gases must be reduced – and soon.

Why hasn’t the growing environmental movements and government actions in some countries slowed down the disastrous climate change and its effects from roaring ahead? Well, there are widely recognized obstacles. Technological obstacles related to the intermittency of solar and wind energy generation remains an unsolved problem. There is an immensely costly infrastructure in place that has been designed for fossil fuel production and distribution. Fossil fuel corporations like Exxon Mobil control vast resources and have great influence on government energy policies. The federal government is divided and unable to advance adequate energy policies and programs. The U.S. government has shamefully obstructed any international agreement targeted to CO2 reductions.

But there is more, including basic questions about the potentiality of solar and wind energy. A widely held assumption in environmental circles is that once the energy sector is based on clean, renewable solar, wind, and other renewable energy sources, then catastrophic climate change will be halted. At a minimum, this assumption suggests that humankind here and elsewhere will be given additional time to overcome obstacles in political, economic and other institutional arrangements.

However, there is evidence that conflicts with this assumption. Ozzie Zehner compiles evidence in his book, Green Illusions: The Dirty Secrets of Clean Energy and the Future of Environmentalism. His main point is that the solar and wind in their full life cycle are as bad for the climate as fossil fuels are. Consider a few of the problems associated with solar energy. Zehner writes that the “solar photovoltaic industry is one of the leading and fastest growing emitters” of “hexafluoroethane (C2F6), nitrogen trifluoride (NF), and sulfur hexafluoride (SF6),” all powerful greenhouse gases. Large solar panel arrays require regular and expensive maintenance to keep panels clean. And, in 20 years or so when they are used up, the panels or parts of them will be dumped into the already existing mountains of toxic waste, also a source of greenhouse gases.

If solar and wind energy are not viable renewable alternatives – and this is still a question – what are the options? Hypothetically, we may surprise ourselves and reduce or eliminate our use of fossil fuels, make economies much more energy efficient, and make great strides in reducing our use of energy, especially in the most energy-profligate countries. Hypothetically.