Like many, I was looking forward to what Elon Musk would say about what is easily the most critical and expensive part of building an electric vehicle—the batteries. The presentation was literally breath-taking. Several times I found myself holding my breath as I tried not to miss any important details. Musk and company had gone to great lengths to simplify their descriptions of what they were attempting. Unfortunately for me, I hadn't taken a Chemistry course since 1966 so I found myself fishing in some forgotten waters. Fortunately, it was easy to watch repeats on YouTube so eventually the requisite understanding returned. (I needed four tries ;-)
There is really no sustainable energy future without effective storage. Anyone who has ever lost their electricity knows that life gets extremely difficult VERY fast. Yes, I know humans survived without electricity in hazardous places such a North Dakota in winter. But those people were unusually hardy, strong, and clever. Even so, preparations for winter began the first days of spring. If you had trees, you chopped wood. Trees are stored energy. Unfortunately, there aren't many trees in North Dakota. Fortunately, there are energy sources that will sustain human life up there—lignite coal and then after the 1950s, oil and natural gas. Now that burning fossil fuels has become a big no-no, North Dakota also has abundant wind power but harnessing it as a practical matter requires storage.
Energy storage has been the big scary boogieman since the invention of fire. We like to treat the problem socially the same way we treat hauling out the trash and for many of the same reasons—it is UGHLEE. Clear-cut forests, oil refineries and tank farms, and the like smell funny and in myriad ways are offensive if not serious health hazards. Storage is especially tricky when the energy is electricity. Electricity moves at roughly the speed of light. With tiny exceptions, therefore, electricity must be used the instant it's produced. While this nearly instantaneous speed is easily electricity's most useful characteristic, it seriously hampers more widespread adoption of renewable energy.

