Assessment of Electricity Decarbonization Scenarios for New Zealand and Great Britain using a Plant Dispatch and Electrical Energy Storage Modelling Framework

This paper proposes a methodology to assess the impact of alternative electricity generation and energy storage scenarios for meeting electricity demand on a national level. The method combines real and synthetic electricity generation and demand data to investigate different decarbonization strategies using solar and wind generation and electrical energy storage. This method is applied to provide relevant case studies for two geographically similar electricity systems in New Zealand and Great Britain. Newly available solar and wind data sets at hourly resolution are used within this method for these systems to assess the potential contribution of these technologies and as such, to refresh understanding of the impact of these technologies on decarbonization strategies against historical and future demand patterns. Although wind, solar and storage technologies are found to reduce the carbon emissions in both electricity systems, a key result is quantifying the impact this has on traditional generation as a backup resource. In New Zealand an investment in wind and solar equivalent to less than 15% of the wind/solar capacity in Great Britain is found to (i) reduce fossil fuel use to less than 2% of annual electricity generation requirements in the data assessed and (ii) remove the need for continuous operation of fossil fuel plants. Further, it is shown that existing hydro storage potential could be used to create near complete decarbonization of New Zealand electricity