Adobe Stock/Jeff Metzger
Adobe Stock/Jeff Metzger

Sanjay Shah, Tesla's senior vice president of energy operations, said quotes to potential solar customers will fall by an average of $3,000 to $5,000, representing savings of about 15% to 25%.

The effort is aimed at boosting sales. Two years ago, Tesla acquired SolarCity, the largest residential solar installer in the country, but changes in marketing and sales staffing have reduced installations substantially since then. Tesla stopped door-to-door sales last year and ended an arrangement with Home Depot to sell solar panels in its stores earlier this year.

As a result, sales have slumped, falling to just 93 megawatts installed in the third quarter, compared with the 200 MW a quarter SolarCity installed in early 2016.

Large solar installers on average charge about 10% more than smaller companies, according to a report from the National Renewable Energy Laboratory.

But Shah said the price reductions should make Tesla "highly competitive." By selling directly from its website and some 100 retail stores, Tesla has been able to cut sales and marketing costs in half, Shah said.

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