(Bloomberg) -- Rooftop solar companies SunPower Corp. and Sunrun Inc. posted higher-than-expected sales in the first-quarter as homeowners in California rushed to snap up panels before a cut in a key state solar subsidy. But the sales rush cost a lot in marketing, and now many customers are facing a months-long wait for new installations.

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Both companies had to spend a lot signing up new California customers, which led to booking losses for the quarter.

Sunrun slumped 11% as of 10:38 a.m. in New York. The company late Wednesday reported a $1.12 loss per share, compared with analyst estimates of a loss of 15 cents per share. SunPower fell 6.2%.

SunPower Chief Executive Officer Peter Faricy said the company has a six—month backlog of customers in California. Sunrun is also facing an “enormous backlog” of customers, executives said on an earnings call Wednesday.

New Customers

SunPower is on track to add 90,000 to 110,000 new customers this year after the ramp up in marketing and sales efforts in California, Faricy

“That investment was worthwhile,” Faricy said in an interview, noting that bad weather in the state contributed to a delay in installations.

Investors were keen to see how much business rooftop solar companies would generate as homeowners in California raced to buy panels ahead of the regulatory change. Both SunPower and Sunrun said they were now offering batteries along with solar panels in California that can offer customers savings on their utility bills under the new incentive program.

“There were a number of investments made in the first quarter to make sure we were in a good position to harvest that high volume coming in from a sales perspective,” Sunrun Chief Executive Officer Mary Powell said in an interview. “We wanted to make sure to grab all of that in the interest of customers as well as Sunrun.”

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