相對於傳統能源，可再生能源對環境的傷害較低，因此近來如何有效地使用可再生能源漸漸地受到重視。本研究中，考慮了擁有可再生能源和理想電池的獨立型電力系統，假設負載是可延期的以達到供需平衡。在這個系統中，調度策略(scheduling policies)的主要目的是有效地使用可再生能源，使得負載能夠盡可能快地被供應，並且使能量被浪費的量減到最小。對於這個目的，考慮三種調度策略：(i)無向前看策略(no lookahead policies)、(ii)一時期向前看策略(1-period lookahead policies)和(iii)一時期預測策略(1-period prediction policies)。研究發現：(i)一時期向前看策略總是比無向前看策略好，且這點可透過樣本路徑法(sample path argument)正式地被證明、(ii)增加電池容量對一時期向前看策略的表現影響不大，且這點也可透過樣本路徑法正式地被證明、(iii)增加電池容量對無向前看策略的表現有明顯有效的改善以及(iv)不需要增加電池容量，預測可以有效地改善系統的表現。

As renewable energy resources are more environmentally friendly than the conventional energy sources, the problem of effectively utilizing renewable energy sources has received a lot of attention lately. In this thesis, we consider a stand-alone power system with renewable energy sources and a perfect battery. We assume that the loads to the system are deferrable so that they can be scheduled to balance the supply and the demand. The main objective of a scheduling policy in such a system is to effectively utilize renewable energy sources so that the loads can be served as quickly as possible and the amount of wasted energy can be minimized. For such a purpose, we consider three classes of scheduling policies: (i) no lookahead policies, (ii) 1-period lookahead policies, and (iii) 1-period prediction policies. Our findings are (i) a maximal 1-period lookahead policy is always better than a maximal no lookahead policy, and this can be formally proved by using a sample path argument, (ii) increasing the battery capacity has little effect on the performance of a maximal 1-period lookahead policy, and this can also be proved by using a sample path argument, (iii) increasing the battery capacity is very effective for improving the performance of a maximal no lookahead policy, and (iv) prediction can be very effective in improving the system performance without the need of increasing battery capacity.

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