The Limits to Growth are back, yet another 1970s concept making a comeback. A front-page article in today's Wall Street Journal highlights these new Malthusian fears, based on recent signals that seem worryingly similar to those that made such predictions so troubling a generation ago. Why should they be any more valid now than they were the last time that phrase was commonplace? Another energy crisis has combined with broader commodity price inflation--both related to the improving standard of living of a growing fraction of the earth's population--and it is overlaid with the ultimate reflection of the scale of humanity's impact on the planet: climate change. Surprisingly, though, the article hardly mentions a development with the potential to finesse all these predictions, the large-scale exploitation of renewable energy.
The evidence that we are straining against serious limits is mounting. Is there anyone left who hasn't heard about China's impact on the global markets for oil, coal, steel, copper, and concrete? Add the simultaneous shift of hundreds of millions of consumers to diets richer in animal protein, along with the rapid growth of grain- and oilseed-based biofuels, and agriculture and water supplies look as stressed as industrial commodities. As skeptical as I was about the assumptions behind the 1970s' version of the Limits to Growth, the current situation gives me pause. We face some very ugly competition for all of the necessities of modern life, unless we find a solution that breaks the logic of scarcity without making our other problems worse.
Energy is the key to this, and although fossil fuels are likely to remain important for years to come, we simply don't have enough of any of them to make a material dent in the problems associated with extending real prosperity beyond about a billion Europeans, Americans and lucky Asians to encompass another couple of billion, at least, in the developing world, while lifting the remainder up to acceptable levels. Food-based renewable fuels don't answer; they are a stop-gap at best, buying time for the efficient conversion of non-food biomass to mature. However, even that won't be sufficient, as the world's population grows towards 9 billion by mid-century. After we double the efficiency with which we use energy, and then double it again, only wind, solar, ocean and geothermal power, augmented by nuclear energy, can close this kind of gap, by sidestepping the constraints on what we can dig or drill out of the earth.
Getting there is the problem, of course. It can't happen instantly, and our standard approach of throwing subsidies at all manner of renewables, without regard to their efficiency, energy-return-on-energy-invested, or other measures of long-term viability seems likelier to impede the process than to hasten it. The current debate about taxing the fossil fuel industry in order to fund subsidies for renewable energy would be enhanced by a frank discussion about phasing out all such subsidies, for all forms of energy, creating a bias for efficiency and scale that is lacking today. Higher prices for conventional energy won't sort that out, as anyone who expected $100 oil to make renewable energy cost-competitive has learned. Renewables will only refute the concerns of the Malthusians when they can deliver as much energy as we currently get from coal or natural gas, without being propped up by governments that have other urgent uses for those funds. Achieving that will require an entirely new approach to energy policy, relying a lot more on technology-blind targets and milestones and a lot less on kitchen sinks full of pet projects and programs.