Benefits of Energy Metering

With rising energy costs and increased mandates from government agencies to reduce carbon emissions, it has become essential to better measure and monitor thermal consumption within buildings.

In this edition of 30 Mechanical Minutes, first presented during the Modern Hydronics Summit 2021, HPAC Magazine discussed the relatively recent trend to install thermal energy meters (Btu meters) in multi-residential buildings. Guest speakers were Curtis Bennett, a regular HPAC contributor and product development manager with HBX Control Systems, and Sam Kolias, CEO of Boardwalk Real Estate Investment Trust, owner and operator of multi-family communities across the country.

What are thermal energy meters?

Bennett explains that a thermal energy meter is a device used in buildings that calculates energy consumption used in a hydronic or fluid-filled system, either from heating or cooling. The meters ultimately allow building owners the ability to accurately track energy use and potentially allocate the specific costs to each individual unit.

The meters are made up of three elements: a flow meter on the hydronic system; two temperature sensors (thermistors installed within the water flow) in the supply and return to provide a Delta T; and a calculator which crunches the numbers and spits out a Btu reading.

According to Bennett, the installation process can be straight forward in new-build multi-family buildings where the thermal energy meters would be installed in dedicated areas on each floor and tie-ins could monitor each individual unit.

“(In new buildings) devices would be engineered at the start of the design process,” explains Bennett. However, retrofits in older buildings—where Bennet believes there is a huge potential market—the process is more complex.

“The risers and feeds are inside the walls and not as easily accessible,” says Bennett, who explains the meters may need to be installed inside the suites on the existing hydronic system.

Multiple Benefits

The thermal energy readings, which with more modern units can be sent by WiFi to a remote computer or cell phone app, means owners can have insights into how energy is being consumed at different times of the day in different areas of the building. They can then use this information to identify potential system malfunctions or educate tenants on optimum temperature settings.

“It’s the LED lightbulb philosophy,” explains Bennett. “We need to get these energy conservation items into these buildings.”

Kolias, who owns over 33,000 multi-family units across the country, notes that almost 100% of his properties are heated by hydronics because of its thermal efficiency.

“The way energy prices go, it’s essential for us to measure and be able to determine where the opportunities to conserve are, and there’s no other way than measuring the consumption,” says Kolias. “Energy metering is going to take off, this is going to be universal and mainstream. We see a huge future for radiant heating in buildings and for metering and measuring it.”

Opportunities for the hydronics industry

Bennett says thermal metering systems remain relatively new to the industry across Canada. They are well established in Europe, and like many European technologies are taking time to trickle into the North American market. He sees it as a billion-dollar market already in Europe, so there is a huge potential for niche sectors of the industry to excel.

“There’s room for people who read these meters, there’s room for people who install them, there’s room for people who calibrate them,” says Bennett, and he’s convinced energy metering is going to be great opportunity for the hydronics industry.