Borrego Solar, a San Diego developer which focuses on commercial and government installations, said Wednesday that it has signed a supplier deal with a Chinese maker of photovoltaic panels.

The deal is an sign of how Chinese solar panel makers are gaining a commanding market share of the growing industry in the United States.

The deal comes a week after another San Diego company, said it would get the solar panels for a massive solar farm it is building in the Arizona desert from a Chinese maker.

Borrego will double the capacity it is getting from Yingli as a result of the deal announced Wednesday

"They have become our trusted partners," said Borrego President Aaron Hall.

As a result of the agreement, Yingli will supply more than half of the panels Borrego expects to install this year.

"Together, our companies are bringing green jobs and clean electricity to leading commercial businesses and institutions throughout the U.S.," Liansheng Miao, Yingli Green Energy's chief executive, said in a statement.

Yingli panels were used on a 2.8-megawatt project for the San Diego Community College District and a 1.8-megawatt project for the San Diego County Water Authority.

Sempra Generation said last week it would get the panels for a 150-megawatt project it is building to supply Pacific Gas & Electric from Suntech.

Some of those panels will come from a Suntech plant in Arizona, but most will come from China.

Sempra Generation is a sister company to San Diego Gas & Electric.

Chinese makers like Yingli have a cost advantage over U.S. suppliers, but are capable of making top-notch products, Hall said.

Borrego has not entered into a supplier deal before, he said, but decided to do so this time to make sure it would have the panels needed for big projects it is building.

"Not all product is created equal, so the first-tier, low-cost manufacturers in the world are in high demand," he said. "They have the best price point and the best product."

Price is key to make sure that solar projects pencil out, that is, that the power they produce will be cheaper than buying power from the grid, once subsidies and financing costs are factored in.

Quality is important to convince banks to lend money for projects that are often paid for over many years depending on how much power they produce.

Borrego uses U.S.-made panels on jobs that require them, like those on military installations, he said. But American manufacturers don't make enough panels to supply all its needs.

About half of Borrego's installations are in California, a third of them in San Diego, Hall said.  

Read more about Borrego Solar

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