Any way you cut it, when you’re dealing with America’s energy needs, you’re dealing in big numbers, and this becomes interesting in evaluating the effort, and the energy, required to supplant oil in the U.S. Of course, oil has had a century-plus head start in exploration, expansion and optimal usage, (optimal considering the horrific side effects), so it’s not exactly a fair comparison with alternative fuels, which remain in the early stages of development.

On the other hand, who ever said life is fair?

A standard metric to discuss energy usage is called the “cubic mile of oil,” which isroughly equal to the amount of oil consumed worldwide every year.  In order to replace that cubic mile ofoil, we would require, as calculated by SRI International, 3 million wind turbines, 2,500 nuclear power plants or 200 Three Gorges Dams. And I know you’re wondering about solar. Let’s put it this way: We’d need to cover 250,00 roofs a day with solar panels for the next 50 years to reach that benchmark CMO. That adds up to 4.2 billion rooftops.

The world currently uses about 3 CMOs per year. In 30 years, it is estimated we consume double that – 6CMOs.

Today, oil accounts for a little more than 1 CMO, coal for .8, and natural gas is good for another .6, and nuclear and other sources make up the rest.

You quickly understand that the world is far from implementing any alternative fuel that will replace oil. Still, that doesn’t mean that concerted public and private efforts, and technological breakthroughs, won’t quickly make a substantial dent in ourenergy needs, because need and opportunity drives virtually all human endeavors, especially in a democratic and capitalist world.

And the energy is out there, waiting to be exploited. One simple and daunting measure: The sunlight that reaches the earth in one hour contains enough energy to fuel humanity fora year.

One key will be developing alternative energy sources that suits different regions. This means wind power in Texas, where oilman T. Boone Pickens is building the planet’s largest wind farm, just north of Amarillo, tosolar in the desert southwest, to biofuels in the Midwest, concentrating not on corn but on non-food based feedstocks such as switchgrass, wood chips andforest residues, to geothermal in Hawaii, where the Puna Geothermal Venture plant taps into the massive underground ferment of the Kilauea Volcano, converting steam into electricity and supplying approximately 30% of the Big Island’s energy.

Once again, intimidating though our energy requirements may be, reality changes in a flash. The U.S. spends about $1 trillion per year on energy, or roughly 10% of our gross domestic product. Managing that relentless energy demand, for economic, security, and environmental reasons, and finding and exploiting new sources to the maximum, will determine our national future.