HoCoSto has developed and brought to market a small scale collective heat system with (mostly thermal) energy storage at its core. We store energy from solar collectors, wind power or residual industrial heat in a subsurface tank with water. Combined with a technical room (controls for remote monitoring and energy management + heat pump) and a heat grid this forms a 100% fossil free and 95% CO2 neutral energy system. We can offer seasonal storage or peak buffering for suburban areas (40-400 houses per system), governmental buildings (schools, sports facilities) and industry. New build and existing build (no large renovations needed).