Semprius, a developer of solar technology, has gone back to investors to raise another round of debt financing. The latest raise is the seventh the Durham-based firm has made over the past 14 months.

According to a securities filing made Thursday, Semprius sold $481,582 of a $1.2 million debt offering.

The recent debt fundings total more than $6 million.

The debt deals with target amount and amount sold, according to the securities filings:

  • 2016-03-24: $1,200,000; $481,582; Debt Only
  • 2016-01-12: $1,300,000; $646,905; Debt Only
  • 2015-10-14: $2,000,000; $995,238; Debt Only
  • 2015-07-29: $1,250,000; $501,648; Debt Only
  • 2015-05-18:$1,600,000; $642,110; Debt Only
  • 2015-03-04:$1,600,000;$642,110; Debt Only
  • 2015-01-13: $1,700,000; $1,691,906;Debt Only

Semprius raised eight other rounds of debt financing back through 2013.

Its last major capital raise for equity was more than $30 million in 2012.

Semprius is developing concentrator photovoltaic (CPV) modules to make solar power generation more economical

Investors include Intersouth. Siemens and In-Q-Tel, the investment arm of the Central Intelligence Agency.