A nuclear power station is planned to be built and operated for many years before a district heating system for the nearby city of Basle will have grown sufficiently large to be connected to the station. The design changes on the plant that will allow a retrofit for heat generation and that will not jeopardize the plant construction and operation as a purely electrical power plant until that time have been identified. Turbine extraction, layout, and piping routing are practically the only characteristics that need to be changed at the time of construction. As compared with the total plant costs, only a small additional investment is needed for these changes. Further investments will have to be made in the future when the actual heating station is added to the plant. Estimated heat generation costs justify the decision to carry out the design changes needed now to assure the feasibility of a simple future retrofit.