Folsom Labs wasn't desperate for the $1 million in angel funding it just raised -- the bootstrappedsolardesign and optimization startup is already profitable, according to co-founder Paul Grana.

“By raising when we didn’t need the money, we were able to be very selective about the investors we wanted to work with and ended up with a group of investors that include the most experienced executives in the solar industry,” said Grana.

But startups need to grow fast, so the funding is aimed at extending the software to span far more of the process flow in a solar project, from "initial customer lead to final close." The aim is to lower "industry soft costs with work flow improvements," according to the company.

Paul Gibbs, co-founder and CEO, suggests that the startup will extend its software's reach from "refining residential functionality to generating permitting documents -- and all steps in between."

Investors include Sheldon Kimber, former COO of Recurrent Energy; Tim Ball, founder of REC Solar; and Fred Kittler of Firelake Ventures. According to Kimber, “The solar industry doesn’t need a new semiconductor technology -- it needs tools like HelioScope that help installers design, deploy and finance projects more efficiently."

The company's rooftop solar design optimization software is already generating revenue and proving itself at a long list of customers that includes SunEdison, NRG, Rosendin Electric, and Borrego Solar.

Folsom's PV optimization software was initially aimed at the commercial market, serving as a "poor man's CAD" and an alternative to PVsyst, but it has been increasingly drawn into other market sectors.

By making the software easier to use and allowing the initial solar project design to be in the hands of field personnel and salespeople, projects are faster and cost less money. The software can optimize the project for building features and orientation, inverter schemes, module types, and a number of other project variables.

Kittler of Firelake Capital notes, "Folsom Labs is addressing one of the nodes most critical for reducing the cost of solar deployment: the linkage between the operating and the financial performance of projects. As an investor, it is great to see such intelligence and focus brought to bear on this important problem."

The company's founders say the software can put smaller players on more equal footing with the industry behemoths -- at least when it comes to design optimization.

Outside equity funding means the five-employee firm now moves from lifestyle business to investor-funded startup -- and that usually goes along with new expectations of pace and outcome. Nevertheless, these entrepreneurs are clearly meeting a need, as evidenced by the growing number of seats for the startup's software.

Screenshot of HelioScope rooftop PV design