GM's $550M solar deal is its biggest clean-energy project

GM makes cars. It doesn't usually build power plants. On Nov. 12, the automaker announced a $550 million deal for two new solar farms in Michigan. It's GM's biggest clean-energy project ever. The farms, called Branch Solar and Lake Iris Solar, are being built by a company called NorthStar Clean Energy. Together they'll generate 300 megawatts, enough electricity to run three of GM's factories.

GM isn't building these solar farms itself. NorthStar Clean Energy owns and operates them. GM is simply agreeing to buy the power they produce, likely through a long-term contract. That's a common setup in corporate clean energy deals. A company gets cheaper, predictable electricity without the cost or hassle of owning solar panels. For GM, powering factories with solar also cuts the emissions tied to building its cars. That includes its electric vehicles. It doesn't mean GM's factories are going fully solar. Most of the automaker's plants still draw power from the regular grid, which includes plenty of gas and coal.

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Will deals like this become the new normal for big manufacturers facing rising electricity costs? It's already trending that way. Factories are some of the biggest, steadiest electricity users around. That makes them attractive customers for solar and wind developers hunting for buyers. The more companies like GM sign deals like this, the clearer the signal gets. Solar power, even without subsidies, is becoming simply the cheaper option for running a factory.