The maximum efficiency of a steam turbine is just shy of 50%, by the time you have integrated the whole plant, 23-35% is typical. (so says wikipedia) The sort

The maximum efficiency of a steam turbine is just shy of 50%, by the time you have integrated the whole plant, 23-35% is typical. (so says wikipedia) The sort of solar panels one would use in a large installation are around 23% efficient. So they are close in "power/hectare". From there it is capital costs and cost of operation that will make the decision.