HDF Energy (Hydrogène de France), a developer of large-scale green hydrogen infrastructure and manufacturer of high-power fuel cells, has proposed a solar power farm with co-located energy storage project in South Africa, which they have titled “Renewstable Mpumalanga” and this is the link to the Technology page on their website, which is short of numerical details.
More details were provided by Dexter King’s LinkedIn post.
So a 1500MW solar PV farm, a 3500MWh hydrogen store and a battery of unspecified capacity which I will therefore ignore for now.
Dexter claims this project would be “able to peak close to 500 MW” but here’s my initial analysis.
When hydrogen is used for a solar farm’s co-located daily energy storage, it takes about 5/7ths (71%) of the solar farm’s energy to power the night and 2/7ths (29%) of the solar panels to power the day time assuming that the efficiency of a power-to-H2-to-power is 40% and also assuming that approximately equal amounts of energy are used at night as in the day.
So if nightly regeneration from Renewstable Mpumalanga’s hydrogen storage was limited to 2571MWh this could be recharged using 6429MWh (at an efficiency of 40%) from the average day’s solar generation of 9,000MWh (from a solar farm power of 1500MW @ 25% capacity factor) leaving another 2571MWh for daytime generation.
So an average solar-powered generation of about 214MW, 5142MWh/day peaking at around 340MW, is possible most days, but it is inevitable that on consecutive cloudy, dark days there would not be enough solar energy to sustain this supply to the grid at night, the 3500MWh hydrogen store having discharged all too soon.
So if HDF is promising to supply the grid with a daily peak of close to 500MW then they will also need a 500MW fossil fuel back-up generator to do so reliably!
Scottish Scientist 