Energy storage cabinet operation status diagram

Can energy storage equipment operate in parallel with the grid?

In Section 3.1.1 of the Xcel Energy Guidelines for Interconnection of Electric Energy Storage with the Electric Power Distribution System document (Energy Storage Guidelines document), EConfiguration 1A, the energy storage equipment is not capable of operating in parallel1 with the grid.

Can an energy storage device be interconnected without an interconnection review?

The declaration allows interconnection of the energy storage device without an interconnection review if this mode is secure from change. In Energy Storage Guidelines document Section 3.2.1, Configuration 2A, the energy storage equipment is not capable of operating in parallel with the grid.

Can Xcel Energy interconnect a non-paralleling energy storage system?

If the energy storage system is operated ONLY in a non-paralleling mode, and such operating mode is secured from changes by unqualified personnel and end users2, submittal of this signed declaration allows interconnection of the energy storage portion without an interconnection review by Xcel Energy.

How does energy storage work?

Energy storage operates in parallel8 with the grid. Generation, if present is non-renewable. Metering is standard (non-net-metered). Energy storage and generation, if present, are not allowed to export energy to the grid9. The method of achieving #4 must be fully illustrated in the oneline diagram or described below.

When should ESS be set to 100% battery capacity?

When utility grid failures are extremely rare, it could be set to 100%. In locations where grid failure is common, or even a daily occurrence, such as in some African countries, you might choose to use just 20% of battery capacity and save 80% for the next grid failure. ESS can also be configured to keep the batteries fully charged.

How does ESS work if a utility grid fails?

ESS can also be configured to keep the batteries fully charged. A utility grid failure is then the only time battery power is used as a backup. Once the grid is restored, the batteries will be recharged either from the grid or from solar panels when available.