I agree that it is intermediate plants which are suffering the most - when renewables are producing, there is simply no time window at all when prices are high enough for these plants to operate.

But baseload plants are suffering as well - they get lower prices, on average, than they used to. This is counter-balanced by the increase in gas prices, which means that the base load prices (ie night time) are higher than they used to be, but that helps nukes and coal plants, not the gas-fired plants that actually need to buy that more expensive gas... So gas baseload plants are becoming marginal - or increasing their price.

Some of the utilities are thus moving to convert some of their plants. see this:

UK's SSE idles gas-fired plants on low spark spreads

London, 31 January (Argus) -- UK utility Scottish and Southern Energy (SSE) will take its two oldest combined-cycle gas turbines (CCGTs) out of service in late March for extended maintenance and expects both plants to be off line for at least a year.

(...)

SSE's move to mothball gas-fired capacity amid low spark spreads comes after rival UK utility Centrica said in October that it planned to idle its 245MW Barry CCGT and its 340MW Kings Lynn CCGT -- neither of which are among its oldest gas-fired plants -- during the second quarter of 2012.

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