Evaluating the regional potential for emissions reduction using energy storage

Abstract

Energy storage is an enabler of low carbon electricity generation, however several studies have shown that its use can cause a non-trivial increase in carbon emissions even if the storage has 100% round-trip efficiency. To understand the impact of storage operation and demand response on emissions, it is necessary to determine the marginal emissions factor (MEF) at the time the storage or demand response was operated. This paper presents statistical approaches to determining regional MEFs using data on regional electricity demand and generation by fuel type, with a simple power flow model used to determine consumption emissions by region. The technique is applied to the electricity system in Great Britain in 2018. It is found that the impact of storage varies widely by location and operating mode, with the greatest emissions reductions achieved when storage is used to reduce wind curtailment in areas which consume high levels of fossil fuel generation, and the greatest emissions increases occurring where storage is used for wind balancing in areas where wind is not curtailed. The difference between the highest emissions reduction and highest emissions increase is found to be significant, at 785 gCO2 per kWh that passes through storage.

Environmental and economic impact of household energy systems with storage in the UK

“…The fuel types of CCGT, nuclear, wind, pumped storage, hydro (non-pumped storage hydro), other (mainly biomass CHP), intfr (French interconnector), intirl (Moyle interconnector), intned (Dutch interconnector), intew (East-West interconnector), dedicated biomass, and solar are included to calculate the MEFs. Pimm et al [22] obtained the MEFs in the simulation based on the entire year, which disregarded the impact of the demand variation and the grid mix structure in different months. Sun et al [13] calculated the MEFs separately for each month, which resulted in discontinuous MEFs between months.…”

“…Pinel et al analysed the impact of grid structure on MEFs and highlighted the importance of fully accounting for electricity imports and exports [21] . The proposed smart battery charging strategy facilitates charging at low MEFs when electricity is mainly generated from low carbon sources and discharges at high MEFs when power comes from high carbon sources, thus resulting in a reduction in carbon emissions [22] .…”