> undispatchable resources

Solar is not dispatchable like a gas power plant is as the sun needs to shine to produce electricity. But it can very much be curtailed to any percentage you want. And that is being done globally every day exactly when it would be uneconomical to generate that electricity.

Interestingly this is as opposed to nuclear energy, which is basically never curtailed and always runs at 100% unless needed for maintenance or safety. Which is one of the main factors why nuclear energy is not economical anymore in a modern grid that values flexibility over constant generation.