What does cheap mean? You aren't paying for the same thing - a ccgt plant is super fast and works independent of the weather.

I'm in favour of having it but the reason why you need to over provision is because of the intermittency. This can also push out proper base load (e.g. nuclear) although it's not simple.

You have to think about the portfolio.

In Britain at least there is also a bit of a sleight of hand where the marginal costs are reported but not the CFD strike prices used to incentivise the buildout.