The problem with running nuclear in a dispatchable fashion (apart from technical problems) is not the marginal cost, but the upfront capital cost. Dispatchable

The problem with running nuclear in a dispatchable fashion (apart from technical problems) is not the marginal cost, but the upfront capital cost. Dispatchable capacity needs to have relatively low upfront cost, because it's seldomly used. The marginal cost is less important. Nuclear has a high capital cost, it's a really complex tech.