A.J. Ballard has a passion for finding new ways to make his buildings more resilient and efficient.

As energy manager for the Maine Army National Guard (MEARNG), Ballard wasn’t content with building envelope improvements and a solar photovoltaic installation at MEARNG’s Aviation Support Facility in Bangor, Maine. Instead, Ballard has pioneered the use of micro-combined heat and power (micro-CHP) systems in MEARNG’s facilities to cut energy costs and carbon emissions while improving resilience and redundancy.

Combined heat and power systems save energy and reduce carbon emissions by reusing the heat that is produced when generating electricity. Ballard worked with Dalkia Aegis, a manufacturer, developer, and installer of propane and natural gas micro-CHP systems, to design CHP systems for two of his facilities. The first, a 75-kW micro-CHP system at the Aviation Support Facility, demonstrated how much energy savings micro-CHP can achieve, says Dan Burke, vice president of sales and marketing for Dalkia Aegis.

“We know that it’s cut 30 percent of the facility’s energy consumption, creating about $60,000 of savings per year,” Burke says. The project, which won an Energy Star CHP award, served as a model for future CHP projects with the Army National Guard and specifically for MEARNG’s new Northern Maine Readiness Center (NMRC), a 45,000-square-foot facility in Presque Isle, Maine, serving the Army National Guard 185th Engineer Support Company.

At the Maine Army National Guard’s Northern Maine Readiness Center, two 10-kW micro-CHP units provide domestic hot water and primary heating for the building’s radiant slabs. Photo by Maj. Carl Lamb.

Fueling CHP with propane

The Army National Guard has locations all over the country, and not all facilities have access to natural gas. MEARNG’s Aviation Support Facility and NMRC, for example, could not access natural gas to power the CHP system, so Dalkia Aegis designed the systems to run on propane. “Propane provides that resilience factor,” Burke says. “Even if there is natural gas, some of the facilities that are mission-critical could have both natural gas and propane. Our systems have the ability to run on both.”

The NMRC uses two 10-kW micro-CHP units from Yanmar as the primary heat sources for the low-temperature radiant slabs used in the building, as well as for domestic hot water. The micro-CHP units are tied together with propane boilers for backup heat, with the boilers kicking in automatically when additional heat is needed or if the CHP systems go down.

The micro-CHP system also meets a new directive from the Army to provide resilience and redundancy in its facilities by providing a backup power source. If the NMRC is affected by one of Northern Maine’s numerous outages caused by an aging grid or severe weather, the CHP units continue generating power to keep the facility’s administrative offices functioning.

“Given the storms of the century that are now happening every year, more and more attention is being paid to the expense and the issues that occur when a building doesn’t have power,” Burke says. “It causes folks to reconsider how they look at resilience and backup power. A diesel generator may not do it anymore.”

Fewer carbon emissions than grid energy

While energy savings have historically been the primary driver for facilities looking at CHP systems, resilience and carbon footprint reduction have become more important in recent years, Burke says. He sees a common misconception among potential clients that because micro-CHP systems run on propane or natural gas, that they are creating additional carbon emissions.

In reality, because micro-CHP systems are so efficient, they can heat and power a facility with fewer carbon emissions than relying on today’s power grid. “CHP is something that folks can do today that reduces your carbon footprint immediately,” Burke says. That feature resonates particularly for building owners and architects working in cities where carbon emission reductions are mandated by law.

In the near future, facilities may also be able to bring cleaner fuels into the mix such as hydrogen, which can be mixed with propane or natural gas, and renewable propane or natural gas.

Architects and engineers might also be surprised by the small footprint and quiet operation of today’s micro-CHP systems. A typical unit fits in a 4-by-8-foot footprint about as large as a sheet of plywood, and with noise levels around 70 decibels, they can be the quietest piece of equipment in the boiler room. That makes them a great option for facilities where lots of people are using heat and hot water, such as multifamily buildings; healthcare and nursing homes; hospitality and athletic centers; prisons; and, of course, Army bases and barracks.

“The NMRC is being used as an example with other Army National Guard bases and military installations as a positive example and something that others should do,” Burke says.

Top photo: A.J. Ballard, the energy manager for the Maine Army National Guard, points out some of the engine details of the award-winning combined heat and power system at the Maine Army National Guard Army Aviation Support Facility in Bangor, Maine. Photo by Staff Sgt. Angela Parady.