Oakville, Calif. -- Photovoltaic panels for generating electricity can be attractive investments for wineries, but not if they replace valuable grapevines. Many wineries have installed such arrays on leach fields, building roofs and land not suited for vines.

Luxury Napa Valley wine producer Far Niente found that a conventional solar installation would have taken three-quarters of an acre of valuable Oakville Cabernet Sauvignon-growing land, land that produces about $150,000 worth of high-end Far Niente Cabernet annually.

Instead, it installed a "Floatovoltaic™" solar array, apparently the first floating array of its kind in the solar industry. The Floatovoltaic installation saves the valuable vineyard acreage from being sacrificed for land-mounted arrays.

Far Niente's system consists of nearly 1,000 photovoltaic solar panels mounted on floating pontoons on the winery's vineyard irrigation pond. The pontoons are constructed from large sections of plastic drainage pipe.

Combined with about 1,300 panels on land next to the pond, the array will generate 400 kilowatts of power at peak output, enough to offset the winery's annual power usage and provide a net-zero energy bill.

The Far Niente array is located in the 100-acre Martin Stelling Vineyard, the cornerstone of the winery's Cabernet Sauvignon program, located directly behind the winery. About one acre of vineyard was removed to accommodate the land-mounted portion of the system, but the floating array's positioning on the pond saved about .75 acre of valuable Cabernet vines that would have been ripped out for a total land-mounted system.

Like many wineries, Far Niente was motivated not only by the desire to reduce electric bills but also to be ecologically correct. "We made the move to solar, not because it made business or financial sense, but because my partners and I felt it was the right thing to do from a social perspective," said Larry Maguire, a partner in the winery.

While conventional wisdom holds that utility rebates and federal tax credits make solar a viable option, there is still a huge financial commitment involved.

Maguire said the winery and its sister winery, Nickel & Nickel, have spent $7 million up front in the solar systems. "It will take about 12 years for the rebates and tax credits, combined with the savings from producing our own energy, to offset the costs."

Sister winery Nickel & Nickel installed a land-mounted system, which went live in October 2007. It brought in much of the harvest with solar power. Located in the Sullenger Vineyard on the Oakville winery's estate, the array's 1,904 panels generate 330kW at peak output, offsetting the winery's annual power usage and providing a net-zero energy bill.

Far Niente and Nickel & Nickel join a small, but quickly growing contingent of Napa Valley wineries that are adopting solar power at a rate estimated to be more than 40 times faster than California businesses in general, according to Dan Thompson of Novato-based SPG Solar, the system integrator that developed and installed the wineries' solar systems.

The Floatovoltaic solution came from collaboration between Far Niente and SPG Solar. "We looked at several configurations for our solar array, but they all involved taking out a significant amount of our vineyard, which was not an attractive idea," according to Maguire.

He said that Far Niente partner Dirk Hampson suggested they look into putting the panels on the irrigation pond. After interviewing several companies, it turned out that SPG's sister company, Thompson Technology Industries, had developed, on paper, the technology to float an installation on water. "We provided them with the opportunity to try it," Maguire said.

The conversion to solar is part of the wineries' collective movement toward "conscientious luxury," an integrated program enabling the production of luxury wines through sustainable measures affecting vineyard, winery and day-to-day business practices. While solar is the centerpiece, complementary practices include sustainable and organic farming, powering farming vehicles with biodiesel fuels, recycling, use of hybrid company vehicles and other environmentally responsible measures.

"We will always be committed first and foremost to producing great wines; it's what we've been doing for over 25 years," Maguire said. "Yet, we recognize that our environment is facing significant challenges, and as an agriculture-based business, we have an obligation to do our part and take sustainable measures where possible."

Far Niente was founded in Oakville in 1885 and prospered until the onset of Prohibition in 1919, when the winery was abandoned. Oklahomans Gil and Beth Nickel revived the winery in 1979, restoring the estate to its original grandeur. Far Niente introduced sister wineries, Dolce, devoted to producing a single, late harvest wine, in 1989; and single-vineyard specialist Nickel & Nickel in 1997. Today the Nickel family, along with partners Larry Maguire and Dirk Hampson, remain involved in the wineries, ensuring the businesses will remain independent and family owned for years to come.