What if a battery has less than the duration requirement?

A battery with less than the duration requirement can receive partial capacity value, as shown in Figure 2, representing a linear derate, so a 2-hour battery would receive half the credit of a 4-hour battery, but a 6-hour battery receives no more value or revenue (for providing capacity) than a 4-hour battery in this example.

How long can Li-ion batteries last?

This rule, along with limited additional energy arbitrage value for longer durations and the cost structure of Li-ion batteries, has created a disincentive for durations beyond 4 hours.

Can Li-ion batteries compete with longer-duration storage?

Despite the large potential, there is still significant uncertainty regarding the role of longer-duration storage, and the possible technologies that can compete with Li-ion batteries in a shift toward longer durations.

How long does it take to recharge a battery?

There must be sufficient time to recharge between discharge cycles, and this recharge time increases with decreasing efficiency. An 8-hour device with an 80% round-trip efficiency requires 10 hours to fully charge. But an 8-hour device with a 40% efficiency requires 20 hours to charge.

Will Li-ion batteries reach cost parity?

The market for Li-ion batteries is growing at a fast pace, driven largely by electric vehicles. This will create new innovations and the potential for cost reductions in stationary applications. Reaching cost parity for new technologies will depend on achieving deployments at scale.

Are Li-ion batteries competitive?

The continued decline in the costs of Li-ion batteries has increased their competitiveness over traditional sources.13 A storage plant providing peaking capacity provides two primary sources of value: the value of providing physical capacity, and the value of energy time-shifting.