(In paragraph 12 corrects percentage solar panels contribute to residential system's total cost to 12.5 percent from 3 percent, changes sourcing)
By Nichola Groom
Oct 20 (Reuters) - U.S. home solar companies, believing President Donald Trump will soon slap tariffs on imported panels and make their systems more expensive, are using that threat to juice their slowing sales.
Top independent installer Sunrun Inc and smaller rivals, many of which are part of an aggressive industry lobbying effort opposed to new tariffs on panels, are warning homeowners considering going solar to sign up before tariffs cause prices to rise.
On its web site, Sunrun warns visitors that panel prices could double in 2018, raising the cost of an average installation by $3,000.
"With the uncertainty of the upcoming tariffs on solar panels, there's no better time to go solar with Sunrun," the company's web site says.
Smaller, local installers and solar advocates from California to Massachusetts are also raising the prospect of higher prices at sales consultations, in blog posts and at community events like farmer's markets.
"We are really urging people not to wait until 2018," said Craig Forman, who leads a pro-solar community group in Newton, Massachusetts, that refers interested residents to two local solar contractors.
The marketing strategy comes at a time when the U.S. residential solar industry is in a slump. The new approach, however, has not reversed a slowdown in sales.
There are signs the threat of higher prices may be helping the sales of some installers in the short term. In the third quarter, the number of new U.S. solar permits issued fell 11 percent from the previous year, though that was an improvement from the 24 percent and 16 percent drops in the first and second quarters, according to OhmHome, an online resource for consumers interested in going solar.
In California, the No. 1 solar market, residential solar permits fell 20 percent in the third quarter from the previous year. That was an improvement from the 30 percent decline year to date.
In April, U.S. solar panel maker Suniva filed a petition seeking relief from what it says are a glut of imported panels that have depressed prices and made it difficult for American producers to compete. Last month, the International Trade Commission found imports had harmed domestic manufacturers, setting the stage for Trump to consider imposing tariffs or other relief to protect the sector.
Solar installers, including the industry's primary trade group, the Solar Energy Industries Association, oppose the petition on grounds that it would drive up the price of solar.
The residential solar industry is widely expected to be able to withstand the shock of higher prices better than the utility-scale sector because panels make up a far smaller portion of rooftop systems' total cost - about 12.5 percent, according to a report published earlier this year by the National Renewable Energy Laboratory.
Nevertheless, any uptick in prices would pose an additional challenge to rooftop installers experiencing a far more sluggish market than just a couple of years ago, when installations were routinely doubling annually. For sales processes that can take up to a year from when a homeowner first inquires about going solar, the trade case is giving potential customers a palpable reason to act now.
"Installers are looking for any reason to get back in touch with the customer and a sense of urgency that will make their sales process be shorter," said Vikram Aggarwal, chief executive of online solar marketplace EnergySage.
Not all installers are talking about the trade case. Tesla, for instance, said it is awaiting the final outcome of the case before alerting potential customers.
Gigawatt Inc, a Placentia, California-based company that installs systems under the name GoGreenSolar.com, has seen a "spike" in sales since it began talking to customers about the trade case, according to CEO Deep Patel.
"In the consumers' mind prices are going to go down. Cell phones got cheaper, TVs got cheaper," said Patel. "The last thing you want to do is tell them 'Hey, Mr Smith, the project costs went up a couple of grand.'" (Reporting by Nichola Groom; Editing by Dan Grebler)