http://www.vox.com/2016/4/28/11524958/energy-storage-railI was reading this article on a project hoping to offer energy storage for unstable renewable sources. At first it seemed reasonable until I get to the part where they claim an 86% end-to-end efficiency which seems wildly over estimated. This is a complicated system and I don't have the skills or the time to do my own estimate so it is only a gut feeling. It seems like the solar roadway project.
Anyone care to comment?