Stratified storage systems have been used for over three decades to store thermal energy in tanks with warm water settling above cold water due to density differences. Rock beds can store heat up to 600°C and are used in solar power plants. Buildings can use thermal mass in walls and floors to passively store solar heat for winter use and reject it in summer. Aquifer thermal energy storage involves extracting groundwater in summer to cool buildings and injecting heated groundwater back into aquifers for winter heating using heat pumps, providing efficient heating and cooling to buildings from subsurface storage.

1. BIRLA INSTITUTE OF TECHNOLOGY
SENSIBLE HEAT THERMAL ENERGY STORAGE
Presented By: FAZEEL AHMAD
(MT/ET/10003/18)
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2. CONTENT
• Stratified storage systems
• Rock-bed storage systems
• Thermal storage in buildings
• Earth storage
• Energy storage in aquifers
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3. Stratified storage systems
• Stratified TES system has been in existence for
more than three decades.
• Its has low cost and simplicity.
• The principle of stratified TES tank operation is
based on thermal stratification process.
• Stratification is just a natural process: the
warmth and density of water are inversely
proportional properties.
• This means that warm water will always settle
on top of cold water.
• Energy efficiency is great(NO HEAT LOSS).
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4. Stratified Storage Tank
Areas of application
•For solar thermal systems, to bridge
periods of no sun
•For wood heating, since wood heating is
otherwise difficult to control
•If a heat pump is installed in order to
maintain blocking and standstill times
•For combined heat and power plants, to
use them more efficiently
•For connecting different heating systems
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5. Rock-bed storage systems
• Thermal storage in packed beds of rock has been shown to be promising at temperatures up to 600 °C.
• Thermal storage at high temperatures for solar power plants “is a key technology for the successful exploitation of
this energy source on a significant scale”
• A rock bed heat storage system for a room stores heat by circulating air heated by solar radiation during the day
through an insulated layer of rocks.
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6. Thermal storage in buildings
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7. Thermal storage in buildings
• Passive cooling is a building design approach that focuses on heat
gain control and heat dissipation in a building in order to improve the
indoor thermal comfort with low or no energy consumption.
• Natural cooling depends not only on the architectural design of the
building but on how the site's natural resources are used as heat
sinks (i.e. everything that absorbs or dissipates heat).
• In passive solar building design, windows, walls, and floors are made
to collect, store, reflect, and distribute solar energy in the form
of heat in the winter and reject solar heat in the summer.
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8. Thermal storage in buildings
• Building Envelop (Thermal Mass)
• Building orientation (site, position of window)
• Building configuration (shape & surrounding of building)
• Building component (putti,cement)
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9. Benefits of thermal storage in buildings
• Cost Savings
• Green Building Certification
• Versatility Benefits
• Grid Benefits
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10. Earth storage
• Our Earth Thermal Storage System is an under-concrete slab
(sometimes called “under-floor”, “in-ground” and “ground storage”)
heating system installed in soil or sand under a concrete slab building
foundation.
• The stored energy is only released when the area above it becomes
cool. Otherwise the radiant heat remains where it is so there is no
wasted energy.
• The system is protected from mechanical harm, corrosive chemicals,
and moisture.
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11. Earth Thermal Storage System Benefits
• 100% energy efficient
• Quiet, safe and clean
• Maintenance free and easy to install
• Room temperature can be verified from anywhere in the building
• Superior heating comfort – gentle even temperature from floor to
ceiling
• Rooms can be programmed so that you minimize operating costs
while maximizing comfort
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12. Energy storage in aquifers
• Aquifer thermal energy storage (ATES) is the storage and recovery
of thermal energy in the subsurface.
• ATES is applied to provide heating and cooling to buildings.
• Storage and recovery of thermal energy is achieved by extraction and
injection of groundwater from aquifers using groundwater wells.
• The groundwater that is extracted in summer, is used for cooling by
transferring heat from the building to the groundwater by means of
a heat exchanger. Subsequently, the heated groundwater is injected
back into the aquifer, which creates a storage of heated groundwater.
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13. Energy storage in aquifers
• In wintertime, the flow direction is reversed such that the heated
groundwater is extracted and can be used for heating (often in
combination with a heat pump).
• ATES can serve as a cost-effective technology to reduce the primary
energy consumption of a building and the associated CO2 emissions.
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14. Energy storage in aquifers
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15. Reference
• Bakr, M., van Oostrom, N. and Sommer, W., 2013. Efficiency of and
interference among multiple Aquifer Thermal Energy Storage systems;
A Dutch case study. Renewable Energy, 60: 53–62.
• Kabus, F., Wolfgramm, M., Seibt, A., Richlak, U. and Beuster, H., 2009.
Aquifer thermal energy storage in Neubrandenburg-monitoring
throughout three years of regular operation”, Proceedings of the 11th
International Conference on Energy Storage
• Ni, Z. (2015) Bioremediation in aquifer thermal energy storage.
Dissertation (in press), Wageningen University.
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16. THANK YOU
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