When the Associated Press runs a story on the ”green grudge” between two Hollywood celebrities trying to outdo each other’s green homes, you know green is going mainstream.

Or is it? Are we talking about Angelina Jolie and Harrison Ford finagling over home energy efficiency? Or Madonna and Nicole Kidman scrupulously watching their water use? Nope. It’s Ed Begley Jr. and Bill Nye (the science guy).

According to the AP story, the battle to the death (of carbon footprints) started two years ago when Nye, a former Seattleite, moved one house away from Begley. Immediately there was tension. Nye said he’d beat Begley at his own green game. Begley got jealous of Nye’s solar panels, and so blossomed the now historic rivalry.

In Nye’s corner: a new solar panel system that shows when he’s saving more power than he’s using, an electric fence powered by a matchbox-sized solar panel to keep animals away from his home grown produce, a patio cover made of recycled plastic lumber, copper rain gutters, and an American flag that gets illuminated at night via a light bulb powered by a tiny solar panel.

In Begley’s corner: older solar panels, rain barrels to offset his wife’s 20 minute showers and water plants, composts garbage, cooks in an outdoor solar oven,  an electronic sprinkler system that checks the forecast and shuts down if it is supposed to rain, a white picket fence made of recycled plastic milk cartons… a shtick as a green guy and a TV show on HGTV to share his info with the masses.

So which one is greener?

And are these really the best ways to green a home? Personally, I’m wondering about their energy efficiency, insulation… house materials. Things that are less flashy than a night-lit American flag. 

And while they may not exactly be A-list celebrities a little competition (and publicity) is always said to be good for business. Now if only Brad Pitt and Britney Spears could get in on the game….

And local readers, when Begley was in town at the AIA’s ReGeneration Conference in April, he said Seattle already understands sustainability… and that architects and people in the construction industry here need to keep up the great work and set examples for the rest of the country. Take it for what it’s worth.

For other versions of this story, check out green gossip site Ecorazzi. For information on green celebs go to msnbc here and click on the picture of Brad Pitt to the right (Begley is picture 5). Interested in the least-green celebrities? Visit Ecorazzi again or the Chicago Tribune (P.S., number 4 is Al Gore….)