The idea of storing surplus thermal energy in soil (or water/ice) is not new. But conventional storage units that have a default static volume quickly reach their load limit or destabilize the natural soil and ground water temperatures by inducing too much heat.

The eTank

»   can gather any solar harvest;
»   can gather the yields of any other regenerative energy source;
»   can gather low-temperature energy yields;
»   has practically boundless storage capacity;
»   can be charged and recharged without limit;
»   does not interfere with the natural temperature levels of the soil or ground water.