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Energy Storage Using a Rock-Filled Train on a Hill: https://news.ycombinator.com/item?id=17794547 https://news.ycombinator.com/item?id=17794547
by mhb 8y ago
Energy Storage Using a Rock-Filled Train on a Hill:
https://news.ycombinator.com/item?id=17794547 https://news.ycombinator.com/item?id=17794547