Tesla is opening on Friday a brand-new showroom in New York where it will sell cars, batteries, and solar panels all under one roof, and the new store opening incidentally coincided with a report that said that U.S. residential solar installations are expected to drop by 13 percent this year, after years of double-digit growth. According to the quarterly SEIA/GTM Research U.S. Solar Market Insight, GTM Research forecasts a 13-percent contraction in residential solar in 2017 “as major markets fall and emerging state markets contribute relatively less growth.” After Tesla bought SolarCity last year, it has focused on integration and profit margin growth rather than on expansion and higher sales. Earlier this year, Tesla stopped selling solar installations door-to-door, and thus removed a major channel to reach out to its customers. “If SolarCity accounted for a 30 percent share of the national market and you cut those installation volumes […]