Two solar photovoltaic-thermal (PVT) energy conversion systems are described and their performance tested under laboratory conditions. One of these was a simple Flat Plate (FP-PVT) design, with headers and risers for heat removal the other a fixed linear axis Compound Parabolic Concentrating solar PVT (CPC-PVT) energy conversion system with a heat-pipe for removal of solar gain. Both had a low iron glass cover for high transmissivity of solar radiation, and polycrystalline silicon solar photovoltaic cells adhered to the absorber. Heat loss coefficient for the FP-PVT collector was measured as 4.1W/m2/K and 3.5W/m2/K for the CPC-PVT solar collector. These solar collectors were tested under steady state conditions using the solar simulator facility at the University of Ulster’s Centre for Sustainable Technologies. The FP-PVT and the CPC-PVT had a combined efficiency of 66.8% and 53.4% respectively producing both heat and power.