source: Elizabeth Fitzsimons San Diego Union Tribune 2003.8.24

In farming, there are few things that can be counted upon with certainty.

The amount of rain can vary dramatically from drought to flooding. Crop values soar and plummet with supply and demand. Losses from wind and pests are unpredictable.

Then there is electricity, which since the energy crisis of 2000 and 2001 has come with fluctuations in price and availability. "Growers have very long memories, and no one thinks it won't happen again," said Eric Larson, executive director of the San Diego County Farm Bureau.

But in Southern California, at least, there is one thing farmers can rely on: the sun. If it's hidden by clouds today, it's a good bet it won't be tomorrow.

Some North County growers are managing their energy costs by harnessing sunlight. "Going solar is something a grower can actually do," Larson said.

In Valley Center, off Lilac Road in the heart of avocado and citrus country, there is a pump that each day pushes water over a hill to 4,400 avocado trees.

Each tree, on land belonging to brothers Jerome and Noel Stehly, requires 350 gallons of water a week. That is a lot of water, and the pump that pushes it uses a lot of electricity – 275 kilowatt-hours a day. (By comparison, an average home uses 500 kilowatt-hours a month, according to San Diego Gas & Electric.) Electricity to run the pump cost the Stehlys $18,000 to $25,000 a year.

Frustrated with the rising cost of electricity, and still bitter about the energy crisis, the brothers resolved to find another power source. Both shake their heads when they think back to the crisis, and both fear it could happen again.

Photovoltaic conversion
In 1996, California became the first state to deregulate its energy system. Changing to more of a free-market system, the theory went, would spur competition. Consumers would benefit by lowered costs. Instead, prices soared. The state couldn't secure enough electricity to meet basic needs, and that led to rolling blackouts. Businesses lost money, and homeowners were angry.

At the Stehly ranch now, two massive structures holding 420 solar panels harness the sun's energy, producing enough electricity in a day to run the pump. The 15-watt panels are divided between two structures that face south on a 1.5-acre plot that had been a storage area for mulch.

The sunlight becomes electricity through a process called photovoltaic conversion. The photovoltaic effect was discovered in 1839 by a French physicist named Alexandre Edmond Becquerel when he put two metal plates into a solution. When one was exposed to sunlight, Becquerel noticed a small amount of current resulted.

The first photovoltaic cells were made of selenium, but they could only convert 1 percent of the sun's rays into electric power. More than 100 years later, in 1954, a cell was invented by scientists at Bell Labs. Using silicon, the cells converted 6 percent of the sunlight into electricity.

Today, photovoltaic cells convert 25 percent to 35 percent of the sun's energy. It doesn't necessarily have to be a sunny day for the system to work.

"A little bit of haze throws the sunlight around the panels," said Jim Faaborg, president of Western Solar, the Poway company that installed the system on the Stehlys' ranch. "This is a much more efficient system than one on a house."

Incentives from the state have made the switch to solar power more cost-effective for farmers. The Stehlys' system cost $474,000 to buy and install, but the state paid for half. With tax credits and tax savings from depreciation, coupled with savings on electricity, Jerome Stehly expects the system, installed in May, will pay for itself within five years.

"I didn't want to be the guy who, five years from now, says 'I wish I would have put that in,'" Jerome Stehly said.

Surplus energy goes back to the power company's grid, and the Stehlys' account is credited. However, they will not be paid at the end of the year if they produce more energy than they use.

Attracting notice
The Stehlys' system was the largest Western Solar had installed. Jerome Stehly plans five more on other groves. He said other growers have come by to see the system.
"They've been out here and seen this and say 'Heck, maybe I should be doing this,'" he said.

Michael Rote, owner of Rote Greenhouses, and Mark Collins of Evergreen Nursery were among the first growers in the county to install major solar-power system. Last summer, Rote put a 39.6-kilowatt system on top of a 135,000-square-foot building at his San Marcos operation. He expects the system to pay for itself in 10 years.

"There's no moving parts, so there's not a whole lot that could go wrong," Rote said.

"I'd looked at the electric problem we had when we had the energy deregulation. I figured this was a cushion against any increases."

Energy from the solar panels powers Rote's entire San Marcos operation: fans, the water recycling system, boilers and heaters.

The solar-energy industry, commercial and residential, is growing once again, by 25 percent a year, said Brad Collins, executive director of the American Solar Energy Society in Boulder, Colo. There are no statistics about how many farmers use solar power in San Diego County.

The systems on farms are typically used for water pumping, which requires a significant amount of power. Farmers want something they can rely on, Collins said.

"Energy tends to fluctuate, and that variability is what kills you," he said. "The reason is the source. There's fuel involved for the production of electricity today. When you produce it from a renewable source, there's none."

Larson of the county bureau said the move to solar is purely cost-driven. But there are a few, like Nino Cupaiuolo, who are devoted to conservation.

"We firmly believe in it," said Cupaiuolo, who farms cherimoyas, persimmons and blueberries on his farm east of Oceanside.

The couple heat their home's water with solar energy and drive a Toyota Prius, a gas and electric hybrid. This spring for his wife's birthday, Cupaiuolo bought his wife a solar oven.

He installed the 36-panel system for his home in September 2000 and is considering a system for watering his groves.

Despite differences in motives in going solar, farmers share this: the distinct satisfaction of watching their electric meter run backward.