Category: Energy Storage
The question as to whether grid scale Hydrogen Storage (HS) is ready for prime time (is it cost effective?) is important to the solar industry, the US electric grid and investors because solar energy is intermittent. Having cost effective grid scale (> 200 MW | >1,400 MWh) solar energy storage will convert GW of intermittent solar generation on the grid into GW of base line solar generation on the grid. Just as important, GW of base line solar generation supports the implementation of the Paris Climate Agreement goal of reducing carbon emissions and, therefore, global warming. This presentation discusses the energy storage cycle for both a pumped hydro energy storage plant (PSP) (currently the most cost effective grid scale energy storage technology) and a hydrogen energy storage plant (HSP) (one of many proposed grid scale energy storage technologies). The presentation uses the author’s previously presented (SPI-17) levelized cost of energy storage algorithm (LCOS) to determine the cost of energy storage at a specific plant. The presentation first discusses the financial and technical principles of the levelized cost (LC) method for computing the cost of storing of solar energy (LCOS). The LC algorithm is agnostic between the two energy storage technologies. The LC algorithm requires nine energy storage plant specifications (specs; metrics) for each energy storage plant studied. Knowing how to compile the nine energy storage plant specs (metrics) from public (or assembled from internal) sources is the key to using the author’s LC algorithm. The audience will benefit from the presentation’s case study approach. The first case study is for the Cabin Creek Pumped Hydro Storage Plant (300 MW│1,450 MWh) [Georgetown, CO 80444]. The author uses the Cabin Creek case study to discuss the PSP technology, to show how the nine Cabin Creek specs are compiled and to compute the PSP LCOS. The second study is for a yet to be determined HSP. The author uses the HSP case study to discuss the HS technology, to show how the nine HSP specs are compiled and to compute the HSP LCOS. The presentation ends with the author comparing the computed PSP LCOS with the computed HSP LCOS. The comparison shows that at this time while the HSP may technically store solar energy, HS is not yet cost effective and is, therefore, not yet ready for prime time on the US electric grid.
Michael Stavy– Senior Advisor, Renewable Energy Finance and Taxes