As expected, Tesla completed its $2.6 billion acquisition of SolarCity, a company spokesperson confirmed Monday. The deal unites two of Elon Musk’s companies, enabling the billionaire to sell both electric cars and solar roofs to his customers under one corporate brand.

Last week, over 85 percent of Tesla shareholders approved the deal, which was first announced by Musk back in August. At the time, Tesla said that merging the two companies would allow them to scale their battery and solar energy operations. The resulting firm would be "the world's only vertically integrated sustainable energy company."

Musk has said the deal is “blindingly obvious” because, in his mind, the desires of Tesla customers overlap with those of SolarCity. But the acquisition could be incredibly dangerous for Tesla, and Musk himself. It’s a long-term investment with no real short-term payoff, and both Tesla and SolarCity will need a lot of cash to stay operational until this deal starts to bear fruit.

Merging the two companies is part of Musk’s Master Plan, which has Tesla expanding its offerings to include integrated energy generation and storage, entering the electric truck and bus markets, and vehicle sharing. The first product to come out of the newly combined company is likely to be the Solar Roof Tesla showed off last month.