This invention relates to hydrogen production using combined heat pumps and a thermochemical cycle. The phthalocyanine comprises one or more sulfonate groups and a counterion of at least one sulfonate group is a phosphonium cation. When employed in a pupil centric geometry the spectrometer has no coma or image distortion. After insertion into the borehole the desired length of conduit intended to resist internal collapse forces and be substantially buoyant, a plug is attached at the upper end.