It's happening again: Elon Musk is having a huge day.

This morning, SolarCity announced that it purchase Silevo, a solar panel manufacturing company, and said it wants to build one of the world's largest solar plans in New York state.

SolarCity shares are exploding following the news, up as much as 19% in afternoon trading.

This chart shows the huge move in SolarCity.

Additionally, The New Jersey Assembly yesterday passed a bill that would allow Tesla to resume sales of its cars in the state.

Tesla shares are up about 4% today.

Yesterday, shares of Musk's companies — Tesla and SolarCity — rallied after a report in The Financial Times said Tesla's electric car rivals Nissan and BMW could look to collaborate on a charging network.

Tesla gained 8.8% yesterday, while SolarCity gained 4.5%.

Musk is the CEO of Tesla and serves as the chairman of the board at SolarCity.