The comparatively large size of nuclear power plants requires increasing the amount of available reserves to offset, according to the N-l criterion, the risk of a frequency drop in the case that a nuclear plant would trip. These nuclear system costs are real and were estimated as being in the range of USD 2 to 3 per MWh, slightly above those of other dispatchable technologies. Variable renewables such as wind and solar, however, generate system effects that are, according to the results reported in Chapter 3, at least an order of magnitude greater than those caused by dispatchable technologies.