In comparison, system costs for dispatchable technologies such as nuclear, coal and gas are at least one order of magnitude lower, i.e. below USD 2 per MWh. For instance, a significant share of hydroelectric resources would provide some or all of the flexibility required to integrate variable renewables and thus limit the increase in system costs. Depending on their technical characteristics, which differ according to the reactor type, nuclear energy further contributes to the flexibility provision in low-carbon systems.