During the special SolarCity shareholders meeting, at which they agreed to the merger with Tesla, CEO Elon Musk stunned the room by promising that the company's solar roof tiles will actually cost less than normal roof tiles—even before calculating the savings in electricity. That's a bold assertion, and one that the company wasn't making when it first announced the new solar tiles last month, but Musk offered his reasoning.
Musk claimed that his solar tiles will be cheaper because the current supple chain for concrete and ceramic roofing is "incredibly inefficient," especially due to their heavy weight. In contrast, he says that his tiles weigh just "a third, a quarter, and sometimes even a fifth" of conventional tiles. As a result, the cost of transporting them and the risk of breakage should reduce the expense: "So the basic proposition would be: 'Would you like a roof that looks better than a normal roof, last twice as long, cost less, and by the way generates electricity?' Why would you get anything else?"