Theoretical Applicability Evaluation of Carnot Batteries for Agricultural Energy Demands in Farms

With the rapid growth of variable renewable energy (VRE) technologies, their high dependence on weather conditions results in significant intermittency. Carnot battery (CB) is considered a promising energy storage technology to enhance their resilience and be applied in residential buildings, communities, and power plants. The potential of CBs applied for agricultural activities in farms is investigated, and their demands differ from those of the above sectors. Two generic systems are studied with a heat pump (HP) to cover power/cooling demands or an electrical heater (EH) to only cover power demands. The indicator gain is proposed to evaluate their economic gain with various hot storage temperatures (Th), grid reliability, the ratio of the diesel and grid price, the proportion of the solar energy after curtailment (e), the proportion used for load directly (u), and specific investment cost of VRE and CBs (cPV, cCB). The gain value in the system with an HP is higher, and the condition to get positive gain for the system only supplying power is harder. In the system with an HP, when e = 1, cPV = 0.15 € / kWh, cCB = 0.40 € / kWh, and Th = 373 K, the gain is with 1.5 ~ 5.8 with u from 0.1 to 0.9. The gain is only within 0.15 ~ 2.5 for another system with cCB = 0.25 € / kWh and Th = 1473 K. The results can be a reference for determining and designing a proper energy solution for farms.