How do non-carbon priorities affect zero-carbon electricity systems? A case study of freshwater consumption and cost for Senate Bill 100 compliance in California
How do non-carbon priorities affect zero-carbon electricity systems? A case study of freshwater consumption and cost for Senate Bill 100 compliance in California
复制标题
DOI：
10.1016/j.apenergy.2020.114824
复制
发表时间：
2020-05
期刊：
影响因子：
11.2
通讯作者：
Brian Tarroja;R. Peer;K. Sanders;E. Grubert
中科院分区：
文献类型：
--
作者：
Brian Tarroja;R. Peer;K. Sanders;E. Grubert
表征不同电力资源组合在满足电力脱碳目标方面的优点和缺点是一个活跃的研究领域。然而，许多系统一级的评估是在尽量减少电力成本的基础上对不同的混合方案进行评估，而没有考虑到区域环境的外部性。加州是一个人口稠密的地区，其积极的电力脱碳政策和水资源短缺问题预计将在气候变化下恶化，这是评估电力脱碳成本和水资源消耗之间权衡的一个有趣的案例研究。因此，本研究结合电网调度模型和区域生命周期淡水消费数据，比较州内淡水消费和电力的平准化成本为四个电力组合方案，旨在实现零碳电力在加州到2045年，符合现行法律（加州参议院法案100）。在模拟的场景中，我们发现，最低的成本发生在由高容量系数和可调度可再生能源实现的较低储能容量需求的混合中。然而，由于严重依赖地热资源，这些混合也导致了高淡水消耗。相比之下，淡水消耗量最低的组合完全依赖于风能、太阳能和水电，与最低成本组合相比，水消耗量减少了一个数量级。由于容量系数较低，供需匹配难度更大（增加储能需求），这种组合使电力的平准成本增加了30%。总体而言，我们的研究结果表明，在实现零碳电力目标时，优先考虑低电力成本以及其他与气候相关的标准，如淡水消耗，将导致与单纯考虑成本截然不同的电力组合。
Characterizing the advantages and disadvantages of different electricity resource mixes in meeting electricity decarbonization goals is an active area of research. Many system-level assessments, however, evaluate different mixes on the basis of minimizing electricity costs without accounting for regional environmental externalities. California represents a highly populated region with both aggressive electricity decarbonization policies and water scarcity issues that are projected to worsen under climate change, representing an interesting case study for assessing the tradeoffs between the costs of electricity decarbonization and water resource consumption. This study therefore combines electric grid dispatch modeling and regional life cycle freshwater consumption data to compare in-state freshwater consumption and levelized cost of electricity for four electricity mix scenarios designed to achieve zero-carbon electricity in California by 2045, compliant with current law (California Senate Bill 100). In modeled scenarios, we find that the lowest costs occurred for mixes with lower energy storage capacity needs enabled by high capacity factor and dispatchable renewables. However these mixes also resulted in high freshwater consumption due largely to heavy reliance on geothermal resources. By contrast, the mix with the lowest freshwater consumption relied exclusively on wind, solar, and hydropower and reduced water consumption by an order of magnitude compared to that of the lowest cost mix. Due to lower capacity factors and greater difficulty in matching supply to demand (increasing energy storage needs), this mix increased the levelized cost of electricity by 30%. Overall, our results show that prioritizing low electricity costs as well as other climate-relevant criteria, such as freshwater consumption, in meeting zero-carbon electricity goals will result in a very different electricity mix than simply considering costs alone.