The clash occurs when renewables are ready for prime time—and natural gas is still hanging around like an old and dirty but reliable car, still cheap to produce and use, after shale fracking is replaced globally by undersea mining of methane hydrate. Revamping the electrical grid from conventionals like coal and oil to accommodate unconventionals like natural gas and solar power will be enormously difficult, economically and technically. Facilities must be constructed to store extra energy for dark, windless days; transmission lines will need to be built to move power from warm places like New Mexico to cold places like New England; grids will have to be reworked to allow small energy producers to share directly with neighbors rather than being forced to pump everything into large power centers. All of this will be a burden on businesses and consumers alike. But it must be done to avert climate change, because electricity generation is responsible for about a third of America’s greenhouse-gas emissions. Roughly similar figures hold true in other developed nations.

Most oil specialists agree that humankind is naturally progressing toward a no-carbon energy future. Our species has already moved from wood to coal to oil to gas, each fuel burning cleaner than its predecessor. Wind, solar, and other renewables are obvious next steps. The problem, scientists say, is that climate change is happening too quickly. Instead of evolving over decades, as happened with the building of the electrical grid, the changeover to renewables has to occur now, faster than any change before.

True, there are ways of buying time. Scientists have experimented, for instance, with injecting carbon dioxide into methane hydrate; for complex chemical reasons, the crystals “prefer” the carbon dioxide, taking it in and expelling natural gas. If undersea methane hydrate could be mined in this fashion, the sequestered carbon dioxide, forever imprisoned in ice beneath the waves, would offset some emissions. This new kind of carbon sequestration could ameliorate some of the long-term environmental damage that widespread global use of cheap natural gas from methane hydrate will do. But even if such techniques work in the way researchers hope, the infrastructure transformation ahead is daunting in scale and scope. It’s like setting up a second Industrial Revolution, only all over the world and in one-third the time.

For years, environmentalists have hoped that the imminent exhaustion of oil will, in effect, force us to undergo this virtuous transition; given a choice between no power and solar power, even the most shortsighted person would choose the latter. That hope seems likely to be denied. Cheap, abundant petroleum threw sand in the gears of solar power in the 1980s and stands ready to do it again. Plentiful natural gas, a geopolitical and economic boon, is a climatological shackle. To Vaclav Smil, the University of Manitoba environmental scientist, the notion that we can move so fast is naive, even preposterous. “Energy transitions are always slow,” he told me by e-mail. Modern energy infrastructures, assembled over decades, cannot be revamped overnight. Worse still, in his view, there is little public appetite for beginning the process, or even appreciating the magnitude of what lies ahead. “The world has been running into fossil fuels, not away from them.”

Smil is correct—the sort of rapid energy transition we need has never occurred before. At the same time, one should note that no physical law says these transitions must be slow. Societies have changed rapidly, even when it cost a lot of money. Nobody can predict the future, but it is dumbfounding to hear left and right alike bemoaning the “reality” that society cannot change, particularly at a time when both sides are bemoaning the consequences of convulsive social change. Natural gas, both from fracking and in methane hydrate, gives us a way to cut back on carbon emissions while we work toward a more complete solution. It could be a useful crutch. But only if we have the wit to know that we will soon have to lay it down.