Massachusetts town tries to make solar power work

Monday, June 7, 2004

GARDNER, Mass. -- This old mill city built prosperity from the force of its waterways. So there was a legacy of renewable energy when the local electrical utility sought to thrust Gardner into the age of inexhaustible sun power, ahead of everyone.

On a summery evening in June 1985, Massachusetts Electric Co. dispatched three managers, two engineers and an analyst to demystify photovoltaic power for about 70 mostly working-class locals gathered in a college auditorium.

Panels that convert sunlight into electricity had been powering satellites. Now they could electrify Gardner's homes, not to mention its library and even the Burger King. They would help the country save oil and coal used by utilities to make electricity.

People listened politely. But what got them excited -- and helped launch the first photovoltaics test on a community scale -- was a question:

How would you like to save up to 40 percent on your electric bills?

Sun-catching panels soon covered rooftops of 30 homes and five other buildings around town. The experiment is still running today, almost 20 years later.

Has solar power worked here? Has it worked around the country? Can it help us get beyond our dependence on fossil fuels?

Yes and no, to all three questions.

Solar electric power, the industry says, has reached as many as 20,000 American rooftops, where it has proved it can supplement electrical grids and trim bills.

But its contribution so far is meager.

Despite technological progress, it hasn't worked reliably enough or economically enough to expand beyond a small fraction of 1 percent of the country's power generation.

15 percent at best

Paul Maycock, who once ran the federal program in photovoltaics, sees its long-range potential as 15 percent, at best. In other words, in the coming age of whatever-replaces-petroleum, it can help greatly -- but even its boosters say it can't carry all the load.

Gardner's solar pioneers discovered the limits of alternative energy the hard way -- by trying it.

In theory, photovoltaics is sheer simplicity: When silicon, extracted from sand and superpurified, is struck by sunlight, it gives off electric current. No generators, turbines or toil.

In a real building, unfortunately, the system isn't so simple.

First, a solar cell's direct current won't run a normal household's appliances. It must be converted to alternating current by a box called an inverter. At sites far from power lines, a battery bank is also needed to store electricity for times when the sun isn't shining. With acid and hydrogen gas, batteries are heavy, expensive and potentially dangerous.

That's why in Gardner and most other places, photovoltaics are installed in tandem with the existing power grid. The grid handles the load at most times: when the sun sets, clouds thicken or appliances suck more juice than the solar cells can pump.

When the sun comes out, the solar panels take over and send any surplus into the power line for use in the grid. The electric meter spins backward to credit the contribution.

Gardner, a central Massachusetts city of about 20,000, was eager to trail-blaze this new technology.

The 4-by-6-foot solar panels started going up in the waning light of autumn 1985. Leon Rice, a supermarket meat cutter, got one of the first systems.

He looked forward to the savings. And yet as his monthly electric bills arrived, Rice didn't see much change -- perhaps $5 saved in the best months, he says.

"If your goal is to save money, you're not going to do it. If your goal is to save fossil fuel, that's fine -- but I'm a working guy," he said. "If I had it to do over, I think I'd get a windmill."

Today's photovoltaic panels are at least 50 percent better at wringing electricity from sunlight and tougher in resisting nature's assaults. They still hog considerable roof space, though. Compared to coal or petroleum, the sun's energy is dilute. That means it must be harvested by big collectors.

The inverters are still temperamental, solar advocates acknowledge. They chug along well enough for five or six years, then often conk out.

Project engineers quickly declared Gardner's experiment a technical success. It was the economics, even with free systems and upkeep, that proved underwhelming. Average annual electric bill savings were less than $200, one consultant estimated.

With that kind of return, the units needed to operate with virtual perfection for many years. They didn't -- and still can't.

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