Solar photovoltaic (PV) installations in the US have now broken through the 10 gigawatt (GW) barrier, following strong market deployment since the start of 2010. During the first half of 2013, more than 1.8 GW of new solar PV capacity was installed in the US, according to the NPD Solarbuzz North America PV Market Quarterly report.

"The US has now joined an elite group of maturing solar PV markets that have accumulated more than 10 GW of installed capacity,” commented Christopher Sunsong, analyst at NPD Solarbuzz. “Only Germany, Italy, and China have more installed PV capacity than the US. The US is only the fourth country to reach the 10 GW milestone of installed PV capacity.”

Solar PV has been one of the fastest growing energy sources in the US over the past six years, with a compound annual growth rate of over 50% since 2007. Cumulative solar PV installations are forecast to increase an additional 80% over the next 18 months, surpassing 17 GW by the end of 2014.

The rapid uptake of solar PV in the US is being driven by the dramatic solar system price declines observed since 2011. Average installed system prices in the US have declined from around $6/watt two years ago to approximately $4.25/watt for residential installations and $3/watt for large utility-scale PV projects today.

"US solar PV market growth has been stimulated by an increased range of solar incentive programs at the state level,” added Sunsong. “While the Far West and Mid-Atlantic states dominate the 10 GW installed, the Southwest and Southeast regions have recently made strong contributions. Other regions however, such as the Great Plains and Great Lakes, remain largely undeveloped, creating further market upside going forward.”

Solar PV installations in the US have seen significant growth since the start of 2010; 83% of the 10 GW were completed within the past 14 quarters. Almost 1,400 solar PV installations in excess of 500 kW in 39 different states are providing 5.4 GW of capacity, and nearly 40% of that capacity is within California.