Four years ago, before the owners of Honig Vineyard and Winery in California's Napa Valley installed a field of solar panels on their property, their typical energy bill hovered around $5,000 a month. So they were understandably shocked — and delighted — to receive the first bill after they flipped the solar switch in August 2006. The grand total: $1.19.

Honig, which produces about 70,000 cases of wine each year, is one of a growing number of wineries that harness the California sunshine to power production. Outside, of course, the photosynthesizing grapevines feed off the sun's energy, while indoors, the grape crushers, cellar humidifiers and even the light bulbs in the tasting room are powered by converted solar power as well.

The majority of these solar expeditions, like the ones at Quivira Vineyards in Sonoma County and Frog's Leap Winery in Napa — which both boast 100 percent solar power use — have been made financially feasible by national and state-mandated subsidies that offset a large portion of panel installation costs. Once the panels are in place (they're typically installed on the roof of the main winery building, or clustered together on the vineyard as a solar panel field), these wineries are hooked into the Pacific Gas and Electric energy grid. On sunny days, the panels capture and send solar energy to the grid. On rainy and overcast days, the winery runs on the network's reserve of power.

"It's like a big bowl of spaghetti," says Michael Honig, president of Honig Vineyard and Winery. "We are all connected — both pulling power from the grid, and putting back solar." The goal is to net as close to zero as possible in terms of input and output — needless to say, $1.19 is pretty darn close. Still, most wineries keep a backup generator that runs on diesel or another petroleum-based energy source as a safeguard when the power fails. "Anytime the grid goes down, we've got no power, even though we're generating energy up on our roof," says Quivira's winemaker, Steven Canter.

A handful of California wineries, such as Wild Hog Vineyard, avoid the grid altogether. Winemakers and self-described back-to-the-land hippies, Daniel and Marion Schoenfeld bought their first solar panel in 1978 — a surplus panel from a NASA project. Since then, and especially since 1990 when they first started making commercial wines, alternative energy has played a key part in their larger environmental philosophy.

The Schoenfelds run their entire production — a modest 3,000 cases each year, plus a small farm and orchard — on about 20 solar panels plus a hydroelectric power generator. When it comes to living off the grid, they say vigilance is the key. "I can run my big crusher on my system, but you shouldn't try to run more than two light bulbs at the same time" Daniel says. "You have to think about things more." On the flipside, the Schoenfelds aren't vulnerable to regional power outages, like their cousins on the grid. "We get phone calls from our kids in town saying, 'The power is out.' And we'll say, 'Not here!'" Daniel says.

Whether on the grid or off, solar energy has solidified its presence in the California wine scene. The state's abundance of sunshine, coupled with the tax credits — which were recently renewed by Congress — and virtually nonexistent energy bills makes going solar a beneficial business decision, as well as a good move for the planet. Increased attention from consumers is also a plus, as more and more wine drinkers look for a winery's commitment to sustainability. Canter says he's noticed a significant increase in the number of blogs and websites that mention Quivira's solar energy use. "It's really caught people's imagination," he says. "They get to have a warm fuzzy [feeling with their wine]."

        

Last year, in conjunction with the summer solstice, Honig Vineyard and Winery paired up with Peju Province Winery and ZD Wines for an event called Solarbration, which celebrated the growing trend in solar-powered wineries in the Napa Valley Region. The second annual Solarbration will take place June 20 this year.

"We've always been a sustainable winery — even before it was cool," says Honig's director of marketing and retail, Regina Weinstein. "We're also a family-run company. And while the economic benefit of going solar is important, we are most concerned with ensuring that our business and land will be here for future generations."

Vineyards and wineries featured in this story:

• Frog's Leap Winery — Rutherford, Calif.

• Honig Vineyard & Winery — Rutherford, Calif.

• Peju Province Winery — Napa, Calif.

• Quivira Vineyards — Healdsburg, Calif.

• Wild Hog Vineyard — Cazadero, Calif.

• ZD Wines — Napa, Calif.

Related on MNN:

• California's Fetzer Vineyards was sustainable before it was cool

• Bonterra Vineyards uses earth-friendly tactics to make its wine

• Visit MNN's wine channel

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