A combination of capacity markets, long-term supply contracts and carbon taxes would provide a market-based framework to ensure that nuclear energy and other dispatchable low-carbon technologies remain economically sustainable. At the current stage of technological development, low-carbon electricity systems will inevitably be based on high shares of variable renewables and nuclear energy. Hence it is recommended that flexibility resources should be developed based on a systems approach where full costs and interdependencies are recognised. This will require increasing the load-following abilities of dispatchable low-carbon back-up including nuclear, expanding storage, rendering demand more responsive and increasing international interconnections.