The photovoltaic company backed by US utility Avista, energy investor Greenlight Energy Resources and Oak Investment Partners has raised $39m.

US-based photovoltaic company GreenVolts has raised $39m in series C funding from undisclosed investors, according to documents filed with the US Securities & Exchanges Commission (SEC).

US-based venture capital firm Oak Investment Partners was the sole investor in the company’s $30m series B round, in September 2008.

Greenvolts had previously closed $10m in series A financing, in October 2007, led by US-based energy companies Greenlight Energy Resources and Avista Corp. This means the total equity funding the company has raised…