The molten salt pump and valve (P&V) test loops at Sandia National Lab
oratories (SNL) National Solar Thermal Test Facility (NSTTF) operated
between Jan. 1988 and Oct. 1990. The purpose of the P&V test was to de
monstrate the performance, reliability, and service life of full-scale
hot and cold salt pumps and valves for use in commercial central rece
iver solar power plants. The P&V test hardware consists of two pumped
loops; the ''Hot Loop'' to simulate the hot (565-degrees-C) side of th
e receiver and the ''Cold Loop'' to simulate the receiver's cold (285-
degrees-C) side. Each loop contains a pump and five valves sized to be
representative of a conceptual 60-MW(e) commercial solar power plant
design. The hot loop accumulated over 6700 hours of operation and the
cold loop over 2500 hours of operation. This project has demonstrated
that standard commercial scale pump and valve designs will work in mol
ten salt. The test also exposed some pitfalls that must be avoided in
specifying such equipment. Although certainly not all of the pitfalls
were discovered, careful design and specification should result in rel
iable or at least workable equipment.