Thermodynamic analysis of pumped thermal electricity storage
Thermodynamic analysis of pumped thermal electricity storage
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DOI：
10.1016/j.applthermaleng.2012.03.030
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发表时间：
2013-05
影响因子：
6.4
通讯作者：
Alexander J. White;G. Parks;C. Markides
中科院分区：
文献类型：
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作者：
Alexander J. White;G. Parks;C. Markides
越来越多的可再生能源技术用于发电，其中许多技术具有不可预测的间歇性，这将不可避免地导致对电力储存的更大需求。虽然有许多现有的和新兴的存储技术，但大多数都受到地理限制、高资本成本或低循环寿命的限制，很少有足够的规模(就电力和存储容量而言)可以在输电和配电层面上进行整合。本文涉及一个相对较新的概念，这里将称为抽水蓄热(PTES)，它可能对未来的存储需求做出重大贡献。在充电过程中，PTES利用高温比热泵将电能转化为热能，并以显热的形式储存在两个热库中，一个是热的，一个是冷的。当需要时，通过有效地将热泵作为热机反向运行，热能被转换回电能。本文着重于PTES的热力学方面，包括能量和功率密度，以及不可逆性的各种来源及其对往返效率的影响。结果表明，对于给定的压缩和膨胀效率，循环性能主要由各油层的最高温度和最低温度之比控制，而不是由循环压力比控制。分析了往返效率对各种损耗参数的敏感性，指出了对压缩和膨胀不可逆性的特别敏感性。
The increasing use of renewable energy technologies for electricity generation, many of which have an unpredictably intermittent nature, will inevitably lead to a greater need for electricity storage. Although there are many existing and emerging storage technologies, most have limitations in terms of geographical constraints, high capital cost or low cycle life, and few are of sufficient scale (in terms of both power and storage capacity) for integration at the transmission and distribution levels. This paper is concerned with a relatively new concept which will be referred to here as Pumped Thermal Electricity Storage (PTES), and which may be able to make a significant contribution towards future storage needs. During charge, PTES makes use of a high temperature ratio heat pump to convert electrical energy into thermal energy which is stored as ‘sensible heat’ in two thermal reservoirs, one hot and one cold. When required, the thermal energy is then converted back to electricity by effectively running the heat pump backwards as a heat engine. The paper focuses on thermodynamic aspects of PTES, including energy and power density, and the various sources of irreversibility and their impact on round-trip efficiency. It is shown that, for given compression and expansion efficiencies, the cycle performance is controlled chiefly by the ratio between the highest and lowest temperatures in each reservoir rather than by the cycle pressure ratio. The sensitivity of round-trip efficiency to various loss parameters has been analysed and indicates particular susceptibility to compression and expansion irreversibility.