It’s a debate that ought to lie at the center of every discussion on sustainability, and yet you seldom hear it mentioned. Leave it to The Economist, then, to thrust it forward onto center stage: do we currently have the technology to support ourselves, or are more advances needed before humanity can safely and equitably meet its energy and resource needs?

Conventional wisdom among proponents of the current shift to sustainability respond with an almost overwhelming “yes.” In his energy challenge to America, Al Gore expresses fully his belief that existing clean energy technologies can meet the current American demand. I dig the optimism, but the fact remains it would take a staggering 740 million five-megawatt wind turbines to match last year’s energy output. Assuming each turbine requires 100 square meters (roughly 1/16th of a mile) of land surface for operation, you’d need a power-generating area that was more than 42 million square miles in size—roughly the entire surface of the continent of Asia.

While wind is far from the most efficient technology humankind has at its disposal, the more powerful options carry heavy burdens. Coal power bears a fistful of issues -- from mercury emissions, to carbon footprint, to the environmental consequences of coal extraction -- and nuclear power brings with it the ever-present dangers of meltdown, radiation, along with the need for safekeeping of spent reactor fuel.  Though these technologies may be able to meet demand by numbers, they may prove self-defeating over the long run, powering an Earth that becomes progressively more unlivable. 

Then there’s the question of resource allocation. Thomas Malthus’s prediction of a world population that would rapidly outstrip its food supply never really came to fruition, as higher yield crops, improved farming techniques, and smaller family sizes kept that crucial balance in line. Yet recent shortages in food and price spikes in oil seem to have restarted the long-dormant ticking of a Malthusian population bomb.  While I wouldn’t start stockpiling just yet, it’s fairly clear that our lone planet could not support the energy and resource needs of 6.5 billion people living at the same consumption levels as the average American. 

So maybe the existing levels of sustainable power and resource distribution -- quantum leaps in terms of environmental friendliness though they may be -- simply aren’t able to power the world into a cleaner, greener future. It seems highly likely that new advances in nanomaterials, carbon sequestration, high-efficiency photovoltaics, and possibly even nuclear fusion will be needed before we can truly call ourselves sustainable. That, or we must dramatically adjust our levels of consumption. If past performance is any indication, though, that’s a sacrifice much of the developed world simply isn’t ready to make.