Prices are rising, demand is increasing, supplies are dwindling. And the environmental impacts of global warming created by fossil-fuel combustion - rising seas, floods, drought, famine, loss of species, etc. - will be devastating.

The continued heavy reliance on coal, oil and natural gas for the production of electricity and transportation puts our lifestyles at risk, our economy in jeopardy, our planet in peril.

Fortunately, there are clean, renewable alternative-energy sources - geothermal, wind, wave, biomass - that can help address the problems. In fact, the most promising alternative rises in the East each and every morning, and provides an inexhaustible fuel supply.

The energy in the sunlight that strikes the Earth in the next 40 minutes will be enough to meet the world's energy demands for the entire year. It's high time we harnessed some of it. And it can be done, according to experts writing for Scientific American magazine. (You can read it by typing Scientific American and "solar power" into your Internet search engine.)

To make a long story short, the scientists say that 250,000 square miles of land in the Southwest are ideal for solar power plants. They absorb 4,500 quadrillion British thermal units of energy per year. Converting a mere 2.5 percent of that radiant energy into electricity would provide enough energy to equal our nation's entire consumption in 2006.

The proposal requires lots of land. About 30,000 square miles of solar panel arrays would need to be constructed. Plus, a high-voltage, direct-current power grid, one less susceptible to energy loss, would have to be built. And underground storage facilities would need to be developed where solar energy would be converted to compressed air, then released to run turbines after the sun goes down.

Another means of harnessing the sun involves using mirrors to heat fluids that would run through heat exchangers, creating steam to turn turbines. Storage is achieved by piping the fluids through tanks of molten salt, which retain heat that can be extracted at night.

These options will require a huge financial investment, $420 billion over 40 years. But the bill can be paid by adding just a half-cent per kilowatt-hour - less than 10 percent - to the average electric bill.

And the ends would justify the means. Solar power plants could provide 69 percent of our electricity by 2050. They would eliminate our reliance on foreign oil, reduce foreign trade deficits, and, by powering hybrid cars, cut our carbon footprint by 62 percent. It sounds like a plan.