The scale of the change required in the world economy over the next few decades, following the passing of peak oil within the next few years, is little short of apocalyptic. Given that our whole civilisation is based overwhelmingly on oil, the dislocation caused when it begins to run out - in 30-35 years' time, according to expert estimates - is likely to be unprecedented in human history.
Already, four-fifths of the world's oil supply comes from fields discovered before 1970. Even finding a new field as vast as Ghawar in Saudi Arabia (the world's largest) - which is almost inconceivable given the huge improvements in geological knowledge over the past 30 years - would only meet world demand for another ten years.
So what is to be done? Market forces will undoubtedly give out strong signals, but they need to be accompanied by strong government strategies ruthlessly enforced in the face of vested interests. One oil industry expert, Colin Campbell, has proposed a so-called Rimini Protocol, whereby countries cut their imports to match the world depletion rate - that is, world annual production as a percentage of what is left, now running at about 2 per cent a year. Poorer oil-less developing countries would be able to afford their minimum needs, and profiteering from shortage by Opec would be avoided. Consumers would be forced to avoid waste by improving energy efficiency, and to switch to renewables.
As with all good proposals, there are downsides. How is it to be enforced? Given that US economic strength depends on rapid growth and ready access to cheap energy, why would President Bush be prepared to sign up to Rimini any more than he is to Kyoto? This is not an argument against it, but other measures are clearly needed. What are they?
A transitional energy economy is more likely to shift first to gas rather than directly to renewables. Gas could be refined into synthetic petrol and diesel for transportation, though this is unlikely to be a major fuel source for about 20 years. However, one important use of gas would be as a transitional feedstock to make hydrogen for fuel cells. That would steadily penetrate vehicle markets and lay the groundwork for the eventual emergence of a hydrogen economy, once the technologies to make hydrogen from renewables (solar, wind or clean coal) become cost-competitive.
Heavy government investment in basic fuel cell research could speed the development of fuel cell cars by resolving critical engineering obstacles such as reliability, material costs (especially platinum catalysts) and fuel storage issues. But consumer attitudes also need to be wrenched out of complacency. One way might be a "feebate" - buyers of vehicles that do 20 miles per gallon or less would have to pay a stiff fee (say, £3,000), while buyers of cars that do 40 miles per gallon or more would get a rebate of the same amount.
Yet the switch to renewables will not be enough by itself. It needs to be linked with a huge programme to improve energy efficiency. The potential here is enormous, since the amount we waste is prodigious. US power plants discard more energy in waste heat than is needed to run the entire Japanese economy. Only 15 per cent of the energy in a gallon of petrol reaches the wheels of a car. Less than a quarter of the energy used in a standard oven actually reaches the food. It has even been estimated that a three-mile-per-gallon improvement in the fuel economy of US cars and light vehicles would be enough to forgo oil imports from the Middle East - surely a better solution than launching an unprovoked and illegal war in Iraq.
But what about nuclear? Isn't this the only thing to save us from carbon-burn extinction? For those advancing such an argument - allegedly the Prime Minister and the Department of Trade and Industry - it is worth pointing out that a rigorous programme of realistic, affordable and cost-effective improvements in energy efficiency across the economy would save more energy than would be generated by building 14 new nuclear power stations.
The switch to renewables is still vital, however, and its potential is greatly underestimated. The US Energy Department estimates that three states - North and South Dakota, and Texas - have enough harnessable wind energy to meet the entire US electricity requirement. Similarly, it has been calculated that Europe's offshore wind potential in waters 100 feet deep or less could cover the whole of the Continent's power. China could double its national electricity generation by harnessing wind energy.
But isn't the price of renewables prohibitively high? In the case of solar power, where the price has already fallen tenfold since 1980, a recent study by the accountancy firm KPMG estimated that the construction of a 300 MW plant (at a cost of only £700m) would bring the wholesale price down to that of conventional energy. Even Ford Motor Co believes that hydrogen fuel cells will become the main power source for transport within 25 years.
It is likely that the energy economy of 2030 will be a hybrid of sorts, meeting demand with alternative fuels and vastly improved energy efficiencies, yet still heavily reliant on hydrocarbons. Maybe a cheaper vehicle fuel cell or a dramatically more efficient solar panel could completely change the path of our energy future. But none of this will happen without strong government intervention to boost research and innovation.
Michael Meacher, MP for Oldham West and Royton, was environment minister from 1997 to 2003
Potential for the future?
Wind Pros: windmills have been a feature of our landscape for centuries; they provide a clean and renewable source of power. Cons: wind farms can be expensive to commission and maintain; piping the electricity to the national grid poses technical problems.
Biomass Pros: produced from fermented and refined organic matter such as sugarcane and oilseed rape, which consume as much carbon dioxide during growth as they produce during combustion; uniquely offers a renewable alternative to liquid transport fuels, with which it can be blended. Cons: needs a lot of space.
Nuclear fusion Pros: has the potential of producing vast amounts of energy; perpetual, cheap and relatively hassle-free, with minimal waste. Cons: fusion technology has a long way to go and at the moment is prohibitively expensive.
Geothermal Pros: in the right places, provides a clean, safe and stable source of power. Cons: effective use depends on the right geological conditions and there are few sites around the world capable of producing power at a competitive cost; it is not strictly renewable - over time, heat-producing sites will cool as more energy is extracted.
Combined heat and power Pros: reduces emissions, waste and cost by transferring the production of electricity to the point of use; well established among larger businesses and public-sector organisations. Cons: it still burns fossil fuel, giving it a limited appeal for the long term.
Hydrogen Pros: efficient, versatile and completely clean - the only emission being pure water; huge potential for transport. Cons: does not occur naturally in a usable form.