Trane TRG-TRC016-EN Absorption Chillers Offer Choice, notes, Types of Water Chillers, period one

period one

Types of Water Chillers

notes

Absorption Chillers Offer Choice

▲Avoid high electric demand charges

▲Minimal electricity needed during emergency situations

▲Waste heat recovery

▲Cogeneration

Figure 19

Absorption water chillers generally have a higher first cost than vapor- compression chillers. The cost difference is due to the additional heat-transfer tubes required in the absorber and generator(s), the solution heat exchangers, and the cost of the absorbent. This initial cost premium is often justified when electric demand charges or real-time electricity prices are a significant portion of the electric utility bill. Because electric demand charges are often highest at the same time as peak cooling requirements, absorption chillers are often selected as peaking or demand-limiting chillers.

Because the absorption chiller uses only a small amount of electricity, backup- generator capacity requirements may be significantly lower with absorption chillers than with electrically-driven chillers. This makes absorption chillers attractive in applications requiring emergency cooling, assuming the alternate energy source is available.

Some facilities, such as hospitals or factories, may have excess steam or hot water as a result of normal operations. Other processes, such as a gas turbine, generate waste steam or some other waste gas that can be burned. In such applications, this otherwise wasted energy can be used to fuel an absorption chiller.

Finally, cogeneration systems often use absorption chillers as a part of their total energy approach to supplying electricity in addition to comfort cooling and heating.

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