The race to find a storage solution for a green energy future. Replacing fossil fuels in the long-term goes by figuring out cost-effective ways of storing energy first. And many are already aware of that, with key figures like Masayoshi Son and Bill Gates investing billions of dollars in the search. Elon Musk even anticipates that Tesla's energy business will be "as big as its car business in the long term." Henry Sanderson explores how the quest for decarbonisation, however, requires radically different thinking.