Solar plus batteries are already cheaper than nuclear, and only going down. Nuclear has always gotten more expensive over time. For the cost of the most recently completed nuclear plant in the US they could have built 12 times the nameplate capacity worth of solar with 24 hours of battery backup. (A totally unnecessary amount of dispatchability.)

Solar and batteries easily "pay" for their manufacturing carbon emissions within 1-2 years max (as does nuclear). This payback period only goes down as the grid gets greener.