Why Thermal Energy Storage (TES)
Use of ice slurry for Thermal Energy Storage (TES) enables utilization of the latent heat of ice and, therefore, allows reduction of the TES tank volume. Furthermore, it enables the flexibility of rapid discharge to address growing load demand.
The VIM is capable of producing up to 1,000 tonR (3,500 kW) cooling capacity at all ambient temperatures. The VIM is based on IDE’s proven technology, which has been operating worldwide for more than 20 years.
Thermal Energy Storage (TES), when compared to other TIC solutions, has an ability to shift the parasitic TIC electric load to off peak hours and, therefore, minimizes parasitic power consumption during the highest power demand period. As a result, the power produced and, consequently, available to the grid is maximized.
In addition, the TES Tank is charged during the off-peak hours. During the on-peak hours, when the demand for, and value of, the power production peaks, TES provides cooling to the compressor inlet air of the combustion turbine and, therefore, ensures a power output at or above ISO rated conditions. Finally, TES provides an increased level of redundancy to the TIC system while shifting parasitic load to off peak hours.
Vacuum Ice Maker (VIM) for Thermal Energy Storage (TES)
IDE Technologies leverages its vast engineering know-how to provide solutions based on the proprietary Vacuum Ice Maker (VIM) technology. Backed by more than 45 years of experience and access to 400 installations world-wide, the Vacuum Ice Maker offers our clients a diverse choice of energy efficient, highly reliable and low maintenance cost applications.
Utilizing its proprietary developed and built energy-efficient VIM, IDE is successfully cooling the world’s deepest gold mine in South Africa, at a depth of 4,000 mr.for the last 20 years. Above the ground, IDE’s VIM systems provide Thermal Energy Storage (TES) for the cooling needs of large industrial and commercial installations. On the other side of the temperature spectrum, IDE’s VIM utilizes any natural body of water to provide clean and inexpensive heat for district heating.[A1]
2. Process Description
Inside the VIM freezer, water is exposed to a deep vacuum. The vacuum forces a small part of the water to evaporate while the other part of the remaining water freezes, forming a water-ice mixture. The mixture is pumped from the freezer as ice slurry into the TES tank until ice concentration in the tank reaches 50% of ice (by mass). In order to maintain the deep vacuum in the freezer, the water vapor is continuously evacuated from the freezer, compressed and fed into the condenser by IDE’s unique centrifugal compressor. In the condenser, the water vapor is condensed using cooling water at 5°C (41°F), which is supplied from a standard water chiller.
During the TES discharge cycle, chilled water at 0°C (32°F) from the bottom of the TES tank is circulated through a heat exchanger in order to meet the required cooling load demand.