Electric car maker and autonomous vehicle pioneer Tesla Motors Inc. has completed its $2.6 billion acquisition of SolarCity Corp., a California-based renewable energy company that specializes in residential solar power.

The deal between the two companies, both started by Elon Musk, became final after approval from over 85 percent of Tesla shareholders last week.

Tesla announced its offer to acquire SolarCity back in July, and at the time, Tesla cofounder and Chief Executive Musk (above) included the deal in his “Master Plan, Part Deux,” which outlined his plans for Tesla’s future. Specifically, Musk framed the SolarCity acquisition as part of his goal to integrate energy generation and storage for Tesla owners.

“[We want to] create a smoothly integrated and beautiful solar-roof-with-battery product that just works, empowering the individual as their own utility, and then scale that throughout the world,” Musk said in a blog post explaining his new plan. “One ordering experience, one installation, one service contact, one phone app.”

Musk actually helped found SolarCity and served as chairman for the company, and he said that the fact that SolarCity and Tesla began as separate companies was “largely an accident of history.” SolarCity agreed to accept Tesla’s acquisition offer in August, which began the lengthy approval process that finally came to completion this week.

The high price tag of the new merger could carry a significant risk for Tesla, as it could be some time before it can fully incorporate SolarCity’s technology into its operations. Still, the long-term effects of the SolarCity deal could put Tesla in an even more powerful position in the growing electric car industry.

Photo by Heisenberg Media