Depends on where in the world you are looking. For example, the EU has a price on CO2 which is going up to reach the EU goals with respect to CO2 emissions. In

Depends on where in the world you are looking. For example, the EU has a price on CO2 which is going up to reach the EU goals with respect to CO2 emissions. In that case, even if storage of electricity is expensive. At some it will be cheaper than burning fossil. Nobody really knows how new nuclear competes with storage. If there is no price on CO2 (and now other regulations that limit fossil), then renewables just have to compete with fossil on price.