Alas, it appears those times may soon return as environmentalists, politicians, and the media push for man’s energy needs to be met once more by the limited capacity of field and fjord. But for one brief moment in man’s planet-killing history, oil was there to carry the burden that man would have otherwise hoisted upon the bowed back of nature. Just look at what oil did for the whales.

In the first age of renewable energy, man was so desperate for even small quantities of transportable hydrocarbon fuel (today so damned for its very abundance), that fleets of ships continually patrolled the oceans in search of ever fewer great whales.

Today it is unbelievable that the intelligent whale, universally regarded as a profound natural wonder, was once appreciated principally as a source of lard. But that very fact is testament to energy’s scarcity before the advent of crude oil. By today’s standards, even a large whale has only a negligible amount of oil – perhaps 200 barrels. The entire world production of whale oil was less than 500,000 barrels per year for most of the 19th century.

Yet for this scant annual prize – equal to about 9.6 minutes of production for today’s oil industry – the world’s whales were hunted so nearly to extinction that even today many remain rare. Many species doubtless would have become extinct had Col. Drake not struck oil in Pennsylvania in 1859. That year, U.S. crude oil production was 2,000 barrels. The next year, it was equal to the entire annual whale oil production of 500,000 barrels. By 1861, crude was pumping at 2,000,000 barrels a year and growing. Within a decade, most of America’s whaling fleet was out of business.

Together with coal, oil opened up an unimaginable quantity of energy that came from outside the contemporary natural productivity of the Earth. For the first time, societies could grow far beyond the biological energy limits of their landmass. Wealth skyrocketed. Food supplies were no longer diverted to energy needs. Populations blossomed, and yet man’s energy-motivated environmental depredations fell significantly.

Fossil fuels have provided freedom from the constraints of biology and agriculture to such an extent that most of us have forgotten exactly how energy-poor a world powered by biofuels can be. Consider that the United States consumes nearly 4.39x1016 BTUs of crude oil per year. In absolute energy value, the entire corn crop in the U.S. could provide just 10 percent of that, and the entire world’s corn crop, only 23 percent.

So if the U.S. can cut energy use by 77 percent, find a 100-percent efficient means of converting corn into fuel, and corner all of Earth’s annual corn crop, we can just get by without oil (assuming coal, nuclear, and gas are still OK). And of course, we’ll need to ignore that corn is plowed, planted, fertilized, harvested, and transported with petroleum energy. Factor that in, and I’m sure we could still squeak by at the equivalent of 20 percent of current petroleum capacity, if we also consumed the world’s entire rice crop. What we (and the Chinese) would eat under this scenario is a little unclear (perhaps we could eat the whales), and I suppose the Europeans would be reduced to living off wind power and pine nuts.

But the exercise demonstrates the burden fossil fuels have lifted from the environment, and how accustomed all six billion of us have become to eating. Even the paltry efforts toward already subsidized biofuels have had an impact. The U.S. demand for ethanol has helped drive the price of corn tortillas beyond the reach of some impoverished Mexicans, precipitating calls for price controls and export restrictions. Unfortunately, the competition between mouths and motors can only increase, and the demands placed on our living planet can only get worse as the second age of renewable energy dawns prematurely.