scope:

This standard applies to thermal storage devices that are charged electrically and discharged thermally. The energy may be stored as latent heat or as sensible heat or as a combination of the two.

The device is charged by electric-resistance heating, and the electric-resistance mechanism is an integral part of, or is located inside, the storage device.

The device is discharged by a heat transfer fluid that enters the device through a single inlet and leaves the device through a single outlet. Storage devices having more than one inlet and/or outlet may be tested according to this standard, but each flow configuration involving a single inlet and single outlet must be tested separately. This standard is not applicable to those configurations in which there is simultaneous flow into the storage device through more than one inlet and/ or simultaneous flow out of the storage device through more than one outlet. The transfer fluid may be either a gas or a liquid or a mixture of the two.

This standard does not include factors relating to cost, life, reliability, or the consideration of requirements for interfacing with specific heating and cooling systems.

The test procedure and equipment outlined in this standard are most easily adaptable to devices used to store thermal energy on the order of l0¹¹ J (10⁸ Btu) or less.

PURPOSE

The purpose of this standard is to provide a standard procedure for determining the energy performance of electrically charged thermal energy storage devices used in heating systems.