The research, which looked at the market in the United States, found installing photovoltaic (PV) systems in the United States fell ‘substantially’ in 2010 and into the first half of 2011.

The drop was revealed in the latest edition of the annual PV cost tracking report by the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), released yesterday (September 15).

The report Tracking the Sun IV: An Historical Summary of the Installed Cost of Photovoltaics in the United States from 1998 to 2010 claims PV installed on residential and commercial properties in 2010 fell by roughly 17% from the year before and by a further 11% in the first six months of 2011.

The report, the fourth in a yearly series, examined more than 115,000 residential, commercial and utility-sector PV systems installed between 1998 and 2010 across 42 states, representing roughly 78% of all grid-connected PV capacity installed in the United States.

Report co-author Galen Barbose of Berkeley Lab’s Environmental Energy Technologies Division said the main reason was the falling cost of PV panels themselves.

He said: “Wholesale PV module prices have fallen precipitously since about 2008, and those upstream cost reductions have made their way through to consumers.”

“The report indicates that non-module costs–such as installation labour, marketing, overhead, inverters, and the balance of systems–also fell for residential and commercial PV systems in 2010.

“The drop in non-module costs is especially important as those are the costs that can be most readily influenced by solar policies aimed at accelerating deployment and removing market barriers, as opposed to research and development programs that are also aimed at reducing module costs.”

According to the report, average non-module costs for residential and commercial systems declined by roughly 18% from 2009 to 2010.

The report has also found the market for solar PV systems in the US has grown rapidly over the past decade, as national, state and local governments offered various incentives to expand the solar market and accelerate cost reductions.

Luke Walsh

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