Abstract
Due to fundamental temporal mismatches between renewable energy generation and demand load, a long-duration energy storage system is required to power Prince Edward Island’s (PEI) electricity system exclusively from on-island wind and solar resources. While a very large lithium battery is a technically capable solution, today’s battery technology is not cost effective; even as wind and solar generation costs become increasingly competitive with fossil fuel alternatives. To explore alternative storage technologies this comparative study utilizes the established hybrid optimization model for multiple energy resources (HOMER) techno-economic modeling tool to perform an application-based high-level comparison of an efficient but costly lithium battery technology solution with a much less efficient but lower-cost thermal-storage with steam-turbine concept; both capable of enabling a 100% wind and solar powered electricity supply for the island. Interestingly, the thermal storage turbine concept is shown to be competitive, at least in principle, with projected cost reductions in lithium battery technologies while also offering a number of distinct practical advantages.
Highlights
Large-scale electric energy storage is at the crux of energy system decarbonization initiatives around the world, and the wide spectrum of capabilities and costs from different storage technologies cause a high degree of uncertainty about the future possibilities are
Darling et al [4] discussed the US Department of Energy future cost target for widespread adoption of $100/kWh for relatively short duration high power batteries for grid smoothing but not the long durations required for 100% wind and solar power supplies
It is worth noting that, for both the lithium battery and the thermal storage, self-discharge losses are not included as they are anticipated to be less than 2% per month in both cases and not critical to the results
Summary
Large-scale electric energy storage is at the crux of energy system decarbonization initiatives around the world, and the wide spectrum of capabilities and costs from different storage technologies cause a high degree of uncertainty about the future possibilities are. The published literature shows a high variance in what cost and application assumptions are made for various large-scale electricity storage options. Budischak et al [1] considered 99.9% wind and solar enabling electricity storage options that have a per-capacity cost of $318/kWh for lithium batteries and $28/kWh for hydrogen fuel cells in 2008 and projected to $192/kWh and $18.2/kWh respectively in 2030. Lazard’s [3] considered a range of electricity storage options, including thermal and compressed air, but only flow, lead-acid and lithium batteries, at $280/kWh in 2018, are assessed in their cost of storage analysis; the other technologies are deemed to be non-commercially viable in the near future. Uncertainty about installed costs and the relative viability of storage technologies is compounded by the reality that the actual
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
