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The ThermoChiller provides refrigeration from any low-grade heat source (<160°F). Engine jacket water, engine exhaust, geothermal hot water and solar thermal collectors can all be used to drive the system. A cooling tower is usually required.

Key Features

  • Low required driving temperatures (down to 160°F)
  • Wide range of heat source options
  • Can deliver chilled water, drive an ice maker, or be used for process cooling/blast freezing
  • Refrigeration output as low as -50°F


Chilling Capacity (Tons): 10 to 5,000 Absorbent: Aqua Ammonia Chilling COP: 0.6 typical


Ice Maker at Kotzebue Electric Association

Kotzebue, Alaska

20-Ton ThermoChiller produces ice in Kotzebue, Alaska. One of Energy Concepts' patented high-efficiency absorption cycles is the "Vapor Exchange" cycle.

This cycle proved ideal to solve the problem of how to transport the large seasonal fish catch from a remote village in Alaska during the warm summer months when commercial salmon season is open.

The VX cycle is powered by low temperature waste heat, which is provided by the jacket cooling water from diesel engines.

Although the absorption cycle has higher first cost than traditional ice making equipment, when the cost of the necessary additional electric generating capacity is included, the total capital cost is lower. Since the absorption system requires no additional fuel input, 80% savings in operating costs is realized.

Diesel engine jacket cooling water at 75°C is used as the heat source to produce 15 tons per day of flake ice for fish storage and transportation.

This project was made possible with support from the Alaska Energy Authority (now the Division of Energy of the Department of Community and Regional Affairs), and the Kotzebue Electric Association.

See more details and photos about the TC-20 at KEA

Chena Hot Springs Resort

Interior of the Ice Hotel, kept cold by a geothermally driven ThermoChiller providing 16 tons of -5°F chilling. It runs on 160°F spring water and will keep Aurora Ice Museum open year round. The Thermochiller uses Energy Concepts' patented double lift Thermochiller cycle.

See the presentation about the Chena Hot Springs Absorption Chiller. Read the detailed write-up about the Chena installation from Energy Concepts (Figures shown here)