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Renewable Heating And Cooling

U.S. Heat Metering Standard

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ASTM E44.25 Subcommittee on Heat Metering

In 2011, ASTM International and the International Association of Plumbing and Mechanical Code Officials (IAPMO) signed a Memorandum of Understanding to develop jointly a U.S. Heat Metering standard under ASTM’s Technical Committee E44 on Solar, Geothermal, and Other Alternative Energy Sources.

Parties interested in this effort are encouraged to participate in ASTM’s E44.25 Heat Metering Subcommittee.

For further information on standards development or ASTM membership, please contact:

About the Proposed Standard

What is a Heat Meter?

A heat meter is a device or instrument that measures the heat absorbed or given up by a heat-conveying fluid across a heat exchange circuit. Three principal subcomponents constitute a complete heat metering instrument: a pair of matched temperature sensors, a fluid flow sensor, and a calculator.

What Will a U.S. Heat Metering Standard Define?

The proposed standard will define the general performance (accuracy) and operational characteristics for hydronic heat meter instrumentation. The scope of the standard does not currently address steam metering.

Why Standardize Heat Meter Instrumentation?

A U.S. heat metering standard would promote a quality market for heat meter instrumentation by allowing manufacturers to meet a single stated performance (accuracy) level for their products. Consequently, manufacturers would no longer compete in the market on accuracy, but instead compete on product cost and other features.

A U.S. heat metering standard would also support consumers in choosing a meter that best meets their project measurement needs. Heat meter standardization would allow for accurate attribution of the energy, financial, and environmental benefits generated from thermal energy sources and renewable heating and cooling technologies.

Additionally, standardization would instill confidence in parties who exchange payments for useful energy delivery and could support greater confidence in the deployment of renewable heating and cooling technologies through innovative third-party financial structures such as energy purchase contracts. This benefit also extends to several states that have included thermal energy as an eligible resource under state renewable portfolio standard (RPS) policies and states that have implemented performance-based incentives to develop renewable thermal markets.