What are the technological options to compensate for – as the German say - the “Dunkelflaute” (dark doldrums), those winter weeks of low winds and low solar? That’s the code that will have to be cracked by Long Duration Energy Storage (above 8 hours and up to several days). Because, if no realistic solution is implemented in the coming years, we will still have gas peakers in the XXIIth century.Gerard and Laurent have invited Michael Barnard, an internationally recognised technology cleantech consultant, with world-class expertise on grid storage technology, electrification, and hydrogen. Together we review and analyse the various options: how far can Li-Ion batteries get us to? How to maximise the value of pumped hydro storage? How to scale flow batteries? Can we even rely of more breakthrough technologies? It will take time, will need government intervention, energy market reforms, but the solutions are there. Long Duration Energy Storage is definitely the “Final Frontier”.ReferencesDisclaimer: Michael works as adviser for Agora Energy Technologies - https://agoraenergy.ca/ Prices of batteries: https://about.bnef.com/blog/battery-pack-prices-cited-below-100-kwh-for-the-first-time-in-2020-while-market-average-sits-at-137-kwh/MIT research:https://news.mit.edu/2021/powering-energy-transition-better-storage-0329https://www.nature.com/articles/s41560-021-00796-8