(Reuters) - SolarCity Corp SCTY.O cut its forecast for solar panel installations this year and reported a bigger-than-expected quarterly loss, sending its shares down nearly 20 percent in extended trading on Monday.

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The company, which is backed by Tesla Motors Inc TSLA.O founder Elon Musk, said it expects to install 1.0-1.1 gigawatts in 2016, lower than the 1.25 GW it had forecast in February.

A pullback in a key solar support policy in Nevada, a January price increase on residential systems and a redesign of its solar loan product were among the reasons SolarCity cited for the lowered forecast.

“We had a bunch of headwinds that hit us all at the same time,” Chief Executive Lyndon Rive said on a conference call with analysts. “These have all been addressed.”

Still, the lower volumes drove up the company’s costs to acquire new business. It will take “about two quarters” to get back to normal customer acquisition cost levels, Rive said.

SolarCity said it raised $728 million in financing during the quarter for its rooftop solar systems.

SolarCity became a Wall Street darling thanks to its innovative no-money-down financing schemes that underpinned a rapid growth in solar installations in recent years. But late last year, the company said it would slow its pace of growth to focus on generating cash.

The slower growth, combined with complex financials that rely heavily on renewable energy subsidies, has spooked some investors. The company’s stock is 65 percent below its 52-week high set nearly a year ago.

In extended trade on Monday, the stock fell to $18.07 after closing at $22.51 on Nasdaq.

Solar panel installments of 214 MW during the quarter, however, were higher than the company’s own expectations as it completed a project in Maryland ahead of time. The company had forecast installations of 180 MW in February.

SolarCity said its net loss attributable to shareholders increased to $25 million, or 25 cents per share, in the first quarter ended March 31, from $21.5 million, or 22 cents per share, a year earlier. (bit.ly/1T1DI9Z)

Total expenses jumped about 54 percent to $226.9 million.

On an adjusted basis, the company posted a loss of $2.56 per share, compared with a loss of $2.32 per share expected by analysts on average.

Revenue rose 81.6 percent to $122.6 million, above analysts’ average estimate of $109.9 million, according to Thomson Reuters I/B/E/S.