ASME PTC 53

Abstract

Types of Systems to Which This Code May Apply This Code applies to mechanical or thermal ESS including, but not limited to, compressed air, flywheel, molten salt, and pumped hydromechanical ESS and sensible, latent, cryogenic, thermochemical, ice-based, or phase-change-material thermal ESS. ASME PTC 53 applies to the measurement of the performance of an ESS at the specified conditions, with all equipment associated with the system functioning in accordance with those conditions. An ESS may use any of various media, including, but not limited to, the following: (a) thermal energy storage media, such as phase-change media (e.g., liquefied air or water-ice) or sensible heating media (e.g., molten salt or thermal fluids and oils) (b) compression media, such as compressed air or springs (c) gravitational media, such as pumped hydromechanical energy or railcars on inclines (d) chemical media, such as hydrogen or ammonia reactions (e) kinetic media, such as flywheels (f) electrolytic media, such as flow batteries This Code provides methods to measure energy and material flows to and from an ESS that are relevant to assessment of ESS performance. For example, some ESS may use energy inputs from multiple external sources. Some ESS may also produce by-products, such as water, carbon dioxide, or industrial gases, that may have economic value or disposal costs of interest to users of this Code. Types of Systems to Which This Code Does Not Apply Electrical battery storage devices (lead-acid, lithium ion, etc.) have been specifically excluded from this Code since the test procedures for that technology have been defined in test codes promulgated by others. UNCERTAINTY This Code requires an uncertainty analysis in accordance with ASME PTC 19.1. The pretest uncertainty analysis is used to develop unit-specific test procedures that result in meeting an agreed-upon target uncertainty. Typical values of test uncertainties, various unit configurations, and performance parameters are presented in Section 3. Test uncertainty is an estimate of the limit of error of a test result. It is the interval about a test result that contains the true value with a given probability, or level of confidence. Test uncertainty is based on calculations using statistics, instrumentation information, calculation procedure, and actual test data. Code tests are suitable for use whenever performance must be determined with minimum uncertainty. Code tests are meant specifically for equipment operating in an industrial setting.