Seasonal storage moves heat from summer to winter. Borehole fields (BTES) heat the ground through vertical heat exchangers; aquifer systems (ATES) pump groundwater between warm and cold wells; pit storage (PTES) uses large lined, insulated water pits.
These stores are huge — tens to hundreds of thousands of cubic metres — so geology, hydrogeology, permits and heat losses dominate the design.
Key facts
- BTES
- Borehole heat exchangers in rock or soil
- ATES
- Warm and cold groundwater wells
- PTES
- Insulated water pits with floating lids
- Duration
- Weeks to seasons
Configurations5
- Borehole thermal energy storage (BTES)
- Aquifer thermal energy storage (ATES)
- Pit thermal energy storage (PTES)
- Underground thermal storage reservoirs
- Seasonal solar heat storage
Site investigations6
- Geotechnical and hydrogeological survey
- Thermal response testing
- Groundwater quality and flow
- Environmental and water permits
- Land availability
- Interaction with nearby wells
Applications4
- Solar district heating
- Seasonal balancing with heat pumps
- Campus heating and cooling
- Industrial waste heat banking
Related calculators
Calculators are available to staff / admin only.
Related topics
- District HeatingAccumulator tanks, pits and boreholes let heat networks run CHP, heat pumps, solar and waste heat at the best hours.
- Heat PumpsIndustrial and large heat pumps upgrade low-grade heat to useful temperatures; storage lets them run at the best hours.
- Solar ThermalFlat-plate, evacuated-tube, trough and Fresnel collectors paired with storage for process heat and district heating.
- Civil & StructuralSite, geotechnics, hot-tank foundations, structures, pipe racks, buildings, drainage and fire-water.
Project & partnership desk
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