Shares Of Elon Musk's Solar Company Are Tanking

Shares of SolarCity, the Elon Musk-chaired solar power service provider, are down more than -5% in after-hours trading after announcing weak quarterly financial results.

The company gave a Q4 earnings outlook of -$0.55 to -$0.65 versus a consensus of -$0.47.

It reaffirmed that it plans to deploy 101 megawatts of capacity in Q4.

"With new energy contracts, MW booked, MW deployed, and operating lease revenue all reaching new highs in Q3 2013, SolarCity continues to demonstrate that demand, execution, and financing remain strong tailwinds supporting growth toward our one million customer goal by mid-2018," said CEO Lyndon Rive. "Moreover, with estimated nominal contracted payments remaining rising to $1.7 billion and cumulative retained value per Watt up to $1.37/W, we are not only creating more value every day but also retaining more value for shareholders with each new customer signed."

Shares of First Solar are also down slightly after hours.