Watermelons - people who are "green on the outside and Red on the inside" - refuse to believe renewable-energy technologies may never be capable of replacing oil and natural gas, but it doesn't stop them from sowing their fantasy seeds.

Their latest loopiness was an Energy Department study this week that claimed windmills could generate 20 percent of the nation's electricity by 2030. All that's required is "more improvements in turbine technology, cost reductions, new transmission lines, an expansion of the wind industry and a fivefold increase in the pace of wind-turbine installation," The Associated Press reported.

"Hand me that piano" is how the British comedy troupe Monty Python used to deride such easier-said-than-done assertions. Wind technology is not ready for prime time; even if it was, NIMBYs won't allow windmills where the wind blows reliably.

But America wouldn't be having this discussion if green energy wasn't so heavily subsidized by taxpayers. According to The Wall Street Journal, the U.S. Energy Information Administration says federal largess per megawatt hour is $24.34 for solar and $23.37 for wind. Coal, by contrast, gets 44 cents, natural gas 25 cents, hydroelectric 67 cents and nuclear $1.59. (The EIA said federal largess for ethanol and biofuels is $5.72 per British thermal unit of energy produced and $2.82 for solar and wind, while natural gas, oil and gasoline get just 3 cents each.)

Even with massive subsidies, renewables can't come close to competing with oil and gas; without them, they'd be dead in the water. Though wind and solar have been on the "subsidy take" for decades, the Journal notes, they produce less than 1 percent of America's electricity; nuclear, meanwhile, generates 20 percent but is subsidized 15 times less.

Believing all renewables, let alone just wind, will produce 20 percent of America's power anytime soon requires a leap of faith only fools would attempt. Speaking of which: Connecticut and other New England states have imposed "20 by '20" mandates - 20 percent renewable-energy generation by 2020 - on their electricity producers.

Northeast Utilities already faces stiff fines for failing to meet its meager 2 percent requirement in 2006 because green-power capacity simply isn't there. Getting to 20 percent, NU says, will require 2,200 new windmills or 8.2 million new solar panels. It also would mean surmounting the aversion of NIMBYs, BANANAs and watermelons to turbines, dams, biomass boilers and fuel-cell farms.

Hand us that piano factory.