Energy savings potential using the thermal inertia of a low temperature storage.

50% of the energy consumed in food cold chain are for chilling, freezing and storage steps. For cold storage facilities, refrigeration is the main source of energy consumption with an average of 50 kWh/m3/year. A possible strategy to reduce their energy consumption is to take advantage of the variation of performance of the refrigeration systems during a day due to external and internal temperature variations. Electricity cost can also widely change during a day, depending on the local production. This strategy can be based on additional storage capacities to delay the refrigeration running period, but also on the use of the thermal inertia provided by the storage warehouse itself and the products stored. An experimental test has been performed in a frozen warehouse storage facility to evaluate the potential energy savings of such a strategy. Using coupled models of the building, products and refrigeration system, using weather forecasts and products flux statistics, a predictive control algorithm was developed and applied to determine periodically the optimal setpoints of the storage warehouse. Technical implementation of the control system is presented. Energy savings potential and impact on products of the temperature fluctuations are also discussed.

食品冷链领域50%的能耗均用于预冷、冻结及仓储环节。冷库设施的核心能耗来源为制冷系统，年均能耗达50 kWh/m³/年。降低此类设施能耗的可行策略之一，是利用制冷系统性能随日内内外温度波动产生的变化特性；同时，受当地电力生产情况影响，日内电价也会出现大幅波动。该策略既可通过增设储能装置延迟制冷系统运行时段实现，也可依托仓储库房与存储货物自身的热惯性来达成。本研究在一座冷冻仓储库房中开展了实验测试，以评估该策略的节能潜力。研究结合库房、货物与制冷系统的耦合模型，依托天气预报与货物流量统计数据，开发了预测控制算法，并将其用于周期性确定仓储库房的最优设定点。本文还阐述了该控制系统的技术实现方案，同时探讨了该策略的节能潜力以及温度波动对存储货物的影响。