The performance of low-conductivity unglazed, transpired solar collectors was determined numerically and experimentally. The numerical work consisted of modeling flow conditions, plate geometries, and plate conductivities with modified commercial computational fluid dynamics software, and the experimental work compared the performance of two plate geometries made with high and low conductivity materials under a variety of flow conditions. Good agreement was found between the numerical and experimental results. The results showed that for practical low-conductivity materials, performance differed little from the equivalent plate geometry in high-conductivity material.