Since Tesla (TSLA -3.40%) announced it would acquire SolarCity last year, it was clear Tesla wanted to do more than own the solar company outright -- it wanted to fully integrate its products into the Tesla brand and give them a design overhaul.

Indeed, not long after the acquisition, Tesla even changed its corporate name to show the importance of sustainable energy to its business. Previously named Tesla Motors, the company, which earns its revenue primarily from sales of electric vehicles, dropped "Motors" from its name earlier this year. The name change reflects Tesla CEO Elon Musk's belief that sales of energy products are going to make up a larger share of the company's revenue in the future.

Of course, Tesla wanted to do more to integrate the energy business: It intended to overhaul the entire SolarCity product line with improved, Tesla-branded solar products. To this end, Tesla is now bringing its recently launched Tesla solar panels to its stores.

Tesla store

Tesla store. Image source: author.

Tesla Solar comes to Tesla stores

Slowly but surely, Tesla is phasing out the SolarCity brand and introducing new Tesla solar products that are sold in Tesla stores.

The first big product change to Tesla's solar business after the SolarCity acquisition was the launch of a new solar product, called the Tesla Solar Roof, which featured solar tiles that can replace shingles and also provide solar power. Next, the company launched Tesla-branded solar panels with a "sleek, low-profile design" in April.

Tesla's new low-profile solar panels

Tesla solar panels. Image source: Tesla.

And now Tesla is displaying "Tesla Solar" marketing materials in some of its stores, shortly after it confirmed a pilot program for selling solar products in its stores proved to be successful. Tesla explained the success in its first-quarter shareholder letter: 

Recently, we tested sales of our solar and storage products in several Tesla stores, and saw sales productivity improve 50% to 100% relative to the best non-Tesla retail locations. Based on these results, we are working towards fully staffing more than 70 Tesla stores in the U.S. and abroad with dedicated Tesla energy sales people over the next two quarters.

The move to sell its new solar panels in its stores highlights how integral solar is becoming to Tesla.

As Tesla ramps up manufacturing of its new solar products, they will almost certainly begin showing up at more Tesla stores.

Revenue and cost synergies

Before the SolarCity acquisition, Tesla said it expected its retail footprint and sales staff to drive revenue and cost synergies thanks to its stores' high foot traffic, brand recognition, and global reach. In addition, Tesla believed there would be overlapping product interest -- for electric vehicles and solar products -- from customers who visit Tesla stores.

As Tesla benefits from these synergies, it has already begun taking the ax to SolarCity's costly sales model. In April, Tesla ended SolarCity's door-to-door sales business in favor of retail and online sales. Eventually, Tesla has said it wants customers to be able to easily walk into any Tesla store and buy electric cars, energy storage solutions, and solar products.