本研究運用EnergyPlus建築模擬軟體，分析空調系統之冰水主機的各種容量組合，並比較各種不同冰水主機組合最低年總耗電量，判斷出何種組合是最為節能的配置。並將最節能的冰水主機配置進行開機策略的分析，求出最為節能的開機策略。冰水主機的容量組合與開機策略對於能源的使用影響相當大，相同的空調負載下，不同的冰機組合及開機策略，會有不同的能源使用狀況。本研究使用一模擬案場，利用EnergyPlus軟體進行建築模擬分析，研究結果顯示，使用最節能組合與最耗能組合比較，一年可省下3.7%的用電量，且進行開機策略最佳化後每日可再省下約1.1%的用電量。

The study targets finding out the most energy-efficient combination between all different types and capacities of chiller groups through the outcome of analysis which based on the EnergyPlus simulations, also to set up the operating schedule and group sequence of chillers to produce the energy optimization outcome. Both grouping chillers under different capacities combination and setting operation schedule to chillers combination is the key to energy-saving. Comparing different types of chiller combinations with in the same total RT condition, the consumption results presenting a difference between each group. Our study result presents possibilities to decrease up to 3.7% annual energy cost comparing the best and the worst performance group by choosing the right combination of chillers. In addition, an extra 1.1% energy was saved by applying an operational schedule for chillers in the annual total electricity consumption.