In some circumstances the use of an enabling technology, either diurnal thermal energy storage or seasonal thermal energy storage (STES, which allows heat or cold storage between opposing seasons), is necessary to make energy recovery practicable. One example is waste heat from air conditioning machinery stored in a buffer tank to aid in night time heating. Another is an STES application at a foundry in Sweden. Waste heat is recovered and stored in a large mass of native bedrock which is penetrated by a cluster of 140 heat exchanger equipped boreholes (155mm diameter) that are 150m deep. This store is used for heating an adjacent factory as needed, even months later. An example of using STES to recover and utilize natural heat that otherwise would be wasted is the Drake Landing Solar Community in Alberta, Canada. The community uses a cluster of boreholes in bedrock for interseasonal heat storage, and this enables obtaining 97 percent of the year-round space heating from solar thermal collectors on the garage roofs. Another STES application is recovering the cold of winter by circulating water through a dry cooling tower, and using that to chill a deep aquifer or borehole cluster. The chill is later recovered from the storage for summer air conditioning. With a coefficient of performance (COP) of 20 to 40, this method of cooling can be ten times more efficient than conventional air conditioning.