You can store excess energy from local microgeneration, particularly solar, that can be used later. With our current pricing model in the UK, that is several times cheaper than selling the excess power to the grid for a token return and then paying full price to have the same amount back from your mains supply later.
Some systems can even be configured to charge their battery from the mains at quiet times (when, again in a typical UK pricing model, the cost-per-unit can be much lower) if there isn’t enough local generation to fully charge it, for example in the middle of winter.
Efficiency.
You can store excess energy from local microgeneration, particularly solar, that can be used later. With our current pricing model in the UK, that is several times cheaper than selling the excess power to the grid for a token return and then paying full price to have the same amount back from your mains supply later.
Some systems can even be configured to charge their battery from the mains at quiet times (when, again in a typical UK pricing model, the cost-per-unit can be much lower) if there isn’t enough local generation to fully charge it, for example in the middle of winter.