I saw that study about two years ago, and I have to tell you that it was challenged pretty quickly. Clearly, any industrial or commercial endeavour has an environmental cost. One of the core reasons, however, that we promote the electrification of transportation and electric vehicles is the reduction in carbon emissions, which is, after all, a fundamental consideration.
That said, our motivation may have more to do with the economic benefits. Economically speaking, we are nearing a point where electric vehicles, grid-based energy storage, and renewable energies are competitively priced.