SSEPP - Space-based Solar Energy Power Plant (1986)
The features of a Space-based Solar Energy Power Plant for electric power generation with a closed cycle gas turbine running on Helium are discussed. The system is intended for generating both electricity and process heat for industrial manufacturing processes in a large space station. A system overview for operation and control of such a plant is presented.
Besides the use of space stations for research and military bases, the industrial use of space as a manufacturing platform will become an important aspect of special economic value in the near future. Space stations as an industrial production environment require large amounts of energy, electricity, process heat, as well as heating for personnel working inside the station.
We are attempting to show the technological and economic feasibility of using large parabolic dish systems equipped with a Helium driven closed cycle gas turbine (HCCGT) utilizing solar energy for electricity and process heat production coupled to a large space station: the electricity consumption is considered to fall within the range of 50 MW and 300 MW for such space stations in an industrial production environment. An equal to slightly larger amount of thermal energy can be extracted from a HCCGT for industrial process heat applications to bring total plant efficiency exceeding 70 % of the input primary energy.
The experience gained in West-Germany operating closed cycle gas turbines over the past 25 years and in particular the design and operation of the Oberhausen Helium Turbine plant permit the transfer of this technology to the space environment. The Oberhausen Helium Turbine plant heating the gas with conventional fuel was intended as a test for commercial power plant use of the Helium technology for the high temperature reactor using Helium as a cooling fluid.
Operation of a large parabolic dish system equipped with a Helium closed cycle gas turbine differs from earth-bound installations considerably; space offers features for the HCCGT that are worth studying, like:
- external pressure is zero,
- outside temperature is near absolute zero K,
- compressor inlet temperatures can be extremely low and thus yield excellent Carnot cycle performances for the HCCGT,
- constant solar radiation as direct radiation at 1353 Watts per square meter for any 24 hour period permits running the HCCGT always at the design point,
- large parabolic dish acts as a protective radiation shield for the space station and its personnel against hard UV and X-rays.
