SolarCity Corp. reported a third-quarter loss of $225.3 million on sales of just $201 million, eight days before shareholders vote on its planned merger with Tesla Motors Inc.

The San Mateo, Calif.-based solar panel-installer narrowly beat analyst expectations, and the financial results were slightly better than the same period of last year when the company posted a loss of $234.3 million on $114 million in revenue.

Shares of SolarCity traded 0.6% higher after hours around $20.12, after closing down 4% on Wednesday. Many solar energy stocks tumbled after news broke that Republican nominee Donald Trump was elected president. Mr. Trump has repeatedly said he wants torepeal federal tax subsidies for renewable energy.

SolarCity installed 187 megawatts of solar panels during the third quarter, down from 256 megawatts installed in the same quarter of 2015. At the same time, operating expenses rose 19% to $258 million.

Elon Musk, who is chairman of both SolarCity and Tesla, said earlier this month that SolarCity would add more than $500 million of cash to Tesla's balance sheet, and that the solar panel installer would contribute more than $1 billion in revenue next year.

Analysts surveyed by FactSet expect SolarCity to report 2016 sales of $694 million, rising to $939 million in 2017.

The company plans to start building a new type of solar roofing product next year in conjunction with Tesla at a factory in Buffalo, N.Y., but didn't offer any new details about how it would finance the operation. The product is part of Mr. Musk's vision for how the two companies' combination would result in an integrated system of solar panels, wall-mounted batteries and electric cars.

SolarCity has an agreement with state officials to spend $5 billion over 10 years at the factory, and the state is spending $750 million on construction and equipment for the project.

SolarCity said it wouldn't hold a conference call with investors and analysts to discuss results this week, pending the outcome of the shareholder vote set for Nov. 17.

Write to Cassandra Sweet at cassandra.sweet@wsj.com

(END) Dow Jones Newswires

November 09, 2016 19:05 ET (00:05 GMT)

Copyright (c) 2016 Dow Jones & Company, Inc.