The emergence of these devices may cause the energy industry to undergo a transformation not all that different from the one computers went through as we moved from mainframes to PCs in the last decade. Micropower, like microcomputers, will rely on sophisticated electronic controls that seamlessly link thousands of small generators and storage devices. With such controls, each solar rooftop, fuel cell and air-conditioner can be connected via digital signals, so that the entire power grid operates as a single smart system, turning individual devices on and off as needed.

Although some fossil-fuel lobbyists and economic modelers still argue that it will be difficult and expensive to find an alternative to oil and coal--and that we should delay the transition for as long as possible--their conclusions are based on a technological pessimism that seems out of place in today's world. The first automobiles and computers were difficult to use and expensive, but as their pioneers persevered and made improvements, they ultimately triumphed in the marketplace. Just as automobiles followed horses, and computers supplanted typewriters and slide rules, so will the advance of technology make today's energy systems look primitive, inefficient and uneconomical.

Unlike fossil fuels, renewable energy is not subject to supply constraints, and geologists will not have to travel to the Alaskan North Slope or the shores of the Caspian Sea to find new sources. The sunlight falling on the surface of the earth each day contains 6,000 times as much energy as is used by all countries combined. European analysts have calculated that covering the flat roof space of existing buildings with solar cells could provide half to three-quarters of the electricity that many cities require. In the U.S., North Dakota, South Dakota and Texas together are swept by sufficient wind to meet the electricity needs of the entire country.

An energy revolution would offer huge business opportunities. Throughout the last century the world's richest person has often been an energy baron, from John D. Rockefeller to the Sultan of Brunei. Today, with the ascendancy of the information age, Bill Gates tops the annual rankings of wealth. But the micropower revolution under way relies heavily on electronic innovations and may create sizable fortunes of its own.

Ultimately the stakes are much higher than that, since today's energy system spews out most of the world's air pollution, including billions of tons of greenhouse gases heating up the atmosphere. For the negotiators who will meet in Kyoto, Japan, this December to grapple with the threat of global climate change--and the need to replace the fossil fuels that are its leading cause--this new generation of energy technologies presents a rare opportunity. If they are able to craft a strong climate agreement that accelerates the energy revolution, we may all breathe a little easier.

Christopher Flavin is senior vice president at Worldwatch Institute and co-author with Nicholas Lenssen of Power Surge: Guide to the Coming Energy Revolution