The batteries and the solar cells themselves are something like shock absorbers for the grid. If drivers want to charge up their cars during peak periods on the grid, the charging station’s batteries will meet part of that demand so that the impact on the grid is milder. Likewise, the solar cells will chip in with some energy, lessening the load on the grid.

“If with new technologies we can control these resources on the distribution side, we can eliminate the need for potentially very expensive upgrades to the distribution system,” said James A. Ellis, the senior manager for transportation and infrastructure at the T.V.A.’s Technology Innovation Organization.