Central storage with batteries

Is storage capability the holy grail of renewable energy, or is there more to it? In the US, grid operators believe the challenge is not so much in storing energy where generated but building energy storage centrally.

There is a system of regulation service purchased by independent system operators in a specialised marketplace. For instance, an additional twenty megawatts of regulation service could support the adoption of the more than 4,000 megawatts of wind power in the New York queue.

Grid operators use regulation services to handle unplanned drops in supply or spikes in demand, like when air conditioning use goes sharply up on a hot afternoon or a power line goes down. Regulation services must be instantly dispatchable. System operators do this by throttling power plants up or down. They believe batteries could do this too, and betteries could do this too, and better, as storage is faster and more flexible than the plants.

The technology to store energy for regulation services is a new tool but is not just theory. It has been deployed in places like Chile where power variability is high. As more renewable energy is added to grid, more such regulation services will be needed to address the variability. Excess renewable energy can be used to charge batteries and balance system variability

This is why the focus has shifted from merely storage to storage centrally. That is where batteries like lithium ion are very efficient.