The Lawrence Berkeley National Laboratory has made public a study regarding the dropping of prices in the case of solar power installations. In 2011 and the first half of 2012, the above mentioned prices have fallen within the ranges of 11-14%. The first six months of 2012 have brought an even bigger decrease in the state of California, with figures between 3% and 7% above the national numbers.
The report made by LBL indicates that the median installed price of PV systems in the year 2011 was $6.10 per watt. This is the case of devices used in residential and small commercial systems that are using less than 10 kilowatts a month.
For large commercial systems that are using over 100kW or more, the price is $4.90/watt. For PV systems in the utility sector, systems that are using over 2000 kW, the average price is of $3.40/W for the year 2011. This is the national data that was gathered, also variation may occur depending on regional basis and based on the installation size of the whole system.
So for talking about different regions, the states we are talking about, for solar systems that are using under 10 kW, the median price of the installation varies between $4.90 and $7.60 per watt. As for other prices, for systems below 2kW was $7.70/W, for major commercial systems with over 1,000 kW, the price is $4.50/W. Utility-scale systems that are running on over 10,000 kW the median price for the installation of a solar power installation is of $2.80-3.50/W, as the study shows.