Residential solar company SunRun has announced a new round of financing from U.S. Bancorp that will support 1,900 residential solar installations.

This is SunRun’s fourth transaction with U.S. Bancorp, which today committed tax equity to develop the installations. No dollar figure was disclosed, however SunRun has previously raised $300 million in project financing from U.S. Bancorp and PG&E. Financing for solar installations is key to the company’s business model.

“We have no business without raising the project financing,” company president Lynn Jurich told VentureBeat in an interview. “We contract with local contractors and roofers and Home Depot to sell our solar power service contracts. It makes it imperative that you don’t run out of project finance capital.”

SunRun buys and installs solar equipment, then leases it to homeowners for little to no money down. It makes money by selling the solar energy generated back to homeowners on 20-year power purchase agreements and claims customers can save 10 to 15 percent on energy bills. SunRun also says it’s the only home solar company that has had an uninterrupted stream of project financing.

“This steady stream of capital speaks directly to our credibility as a reliable and risk-free alternative to the utility,” said SunRun CEO Edward Fenster in a statement.

Right now, SunRun has captured the most market share in a home solar market that has been growing — the company itself says it is growing 300 percent year over year, and installs more than $1 million in solar systems every day. It competes against companies like SolarCity (backed by Elon Musk) and, to a smaller extent, Sungevity.

The company recently expanded to Hawaii. It counts over 6,000 homes as its clients and offers its services in Arizona, California, Massachusetts, New Jersey, Colorado and Pennsylvania.

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