Approaches for providing
backup energy services for a
power grid are disclosed. In embodiments, methods and systems for obtaining a first group of reserve
backup energy batteries of a first type, which have a different
cost structure than a second group of main batteries of a second type. The first group of reserve batteries are combined with the second group of main batteries of the second type to increase a total amount of available energy that is stored and converting DC power from the first group of batteries and the second group of batteries to
AC power to be used for power distribution to the grid.