The child pages along with this one show the geology of around 20 locations in northern onshore UK basins where, in our opinion, groundwater in the temperature range 70-100 degrees Centigrade can be brought to surface at rates adequate to run through a heat exchanger for resulting vapour to spin a bi-turbine set, giving commercial electricity generation. High-efficiency turbine technology wasn’t available in previous decades and it is an enabler for low-temperature geothermal developments.