5 Signs Your Building Is a Good Candidate for MicroCHP

If your building uses natural gas or propane for heat while purchasing electricity from the grid, there may be an opportunity to get more value from the fuel you are already consuming.

Micro combined heat and power (microCHP) generates heat and electricity at the same time, right where they are needed. Instead of operating a conventional boiler solely to produce heat, a microCHP system captures that thermal energy for the building while simultaneously producing electricity that can offset power purchased from the utility.

Axiom Energy Group’s EcoPrime microCHP system is designed to follow a building’s thermal demand, producing useful heat while generating up to 4.4 kW of electricity. With an overall system efficiency of approximately 93%, microCHP can be an attractive option for buildings with the right energy profile.

But how do you know whether your property is a good fit?

Here are five signs that microCHP deserves a closer look.

1. Your Building Has a Consistent Need for Hot Water

One of the best indicators of a strong microCHP application is a steady thermal load.

Think about buildings where hot water is needed every day:

• Multifamily apartment buildings

• Hotels

• Senior living communities

• Dormitories

• Healthcare facilities

• Fitness centers

• Other facilities with significant domestic hot water demand

  
  

Why does this matter?

MicroCHP works especially well when the heat it produces can be put to use for long periods of time. The EcoPrime system is designed to modulate its output based on the thermal needs of the application. As it produces that heat, it simultaneously generates electricity.

A real-world multifamily installation demonstrates the concept. A 4.4 kW microCHP system was installed at a 32-unit apartment building in South Milwaukee, Wisconsin, where recovered thermal energy was used for domestic hot water. During its first year of operation, the microCHP system supplied 100% of the building's domestic hot water thermal requirements without needing to operate the existing backup boiler for that load.

The lesson is simple: the more consistently your building can use the heat, the more opportunity there is to operate the microCHP system and generate electricity.

2. You Have Both a Gas Bill and a Significant Electric Bill

Take a look at your utility bills.

Are you purchasing natural gas or propane to make heat while separately purchasing electricity from the grid?

If so, microCHP introduces another way to use that fuel.

With conventional equipment, natural gas consumed by a boiler is used to produce thermal energy. A microCHP system uses fuel to produce two useful forms of energy: heat and electricity.

That electricity is generated on-site and can offset electricity the building would otherwise purchase from the utility.

For example, during the first year of operation at the South Milwaukee multifamily project, the microCHP system generated 36,106 kWh of electricity. Of that, 30,677 kWh was used by the building's common areas, while the remaining electricity was net metered and sold back to the utility.

Your exact economics will depend on local natural gas, propane and electricity rates, along with how your building consumes energy. But if you're paying meaningful amounts for both heat and electricity, it's worth evaluating whether producing them together can improve your energy costs.

3. Your Boiler Runs Frequently, Even Outside the Heating Season

Many people associate boilers with winter.

But in buildings with substantial domestic hot water demand, the boiler room may stay busy all year.

Showers don't stop in July. Neither do laundry rooms, kitchens or other hot-water loads.

That year-round thermal demand can be particularly valuable for microCHP because it creates opportunities for the system to operate during months when space heating demand is low.

In the South Milwaukee project, domestic hot water consumption provided a relatively steady thermal load throughout the year. The system could modulate its thermal output to follow that demand, helping maximize operating hours rather than simply cycling on and off like conventional boiler equipment.

That is an important distinction.

MicroCHP economics are generally driven by operating hours, not simply the size of the building.

A smaller property with steady year-round hot water consumption may therefore be a better candidate than a larger property with highly intermittent thermal demand.

4. You're Looking to Reduce Dependence on Grid Electricity

Electricity generated hundreds of miles away has to travel through the transmission and distribution system before reaching your building.

MicroCHP takes a different approach: generate energy where it is being consumed.

As the EcoPrime system produces heat for the building, it also produces between 1.2 and 4.4 kW of electrical power, depending on operating conditions and thermal demand.

That electricity can reduce the amount of power the building needs to purchase from the grid.

For a multifamily property, for example, on-site generation might help serve common-area loads such as:

• Hallway and exterior lighting

• Laundry facilities

• Pumps

• Building controls

• Elevators

• Mechanical equipment

• Other common electrical loads

  
  

In the South Milwaukee installation, electricity generated by the microCHP system offset electricity that would otherwise have been purchased for the building's entrance, hallways and laundry room.

MicroCHP doesn't mean disconnecting from the utility. It means reducing how much energy your building needs to pull from it by producing some of that energy on-site.

5. You're Planning a Boiler Upgrade or Mechanical-Room Project

Sometimes the best time to consider microCHP isn't when existing equipment fails.

It's before that happens.

If you're already evaluating a boiler replacement, domestic hot water upgrade, building renovation or mechanical-room project, that's an ideal opportunity to evaluate whether microCHP belongs in the system design.

EcoPrime is intended for installation in a central heating room and integrates with heating-water supply and return, fuel supply, electrical service, controls and complementary boiler equipment. The existing boiler can remain part of the system to provide additional capacity when required.

This makes microCHP particularly interesting as part of a broader mechanical-system strategy.

Instead of asking:

“What boiler should replace our existing boiler?”

It may be worth asking:

“Can some of the fuel we're already using for heat also produce electricity?”

That question can change the economics of the entire project.

What Does a Good MicroCHP Candidate Look Like?

There isn't one building type that works for every microCHP installation.

The better question is whether the property's energy profile makes sense.

A promising candidate often has several characteristics working together: steady domestic hot water or heating demand, consistent electrical consumption, existing natural gas or propane service, long equipment operating hours, and enough simultaneous thermal and electrical demand to use the energy being produced.

Multifamily buildings are a good example because residents create a relatively consistent domestic hot water load throughout the year. Hotels, senior living facilities and other properties with similar energy profiles may offer the same fundamental opportunity.

And the savings can be meaningful.

After analyzing utility bills and operating data from the first year of the South Milwaukee microCHP project, Axiom Energy Group estimated approximately $6,400 in first-year savings, based on the energy prices applicable to that particular project.

Every property is different, which is why the first step shouldn't be selecting equipment.

It should be understanding the building's energy use.

Could MicroCHP Work in Your Building?

If several of these five signs sound familiar, your property may be worth evaluating for microCHP.

Axiom Energy Group can review your building's thermal and electrical demand to help determine whether EcoPrime microCHP is a good fit for your application.

The process starts with something you already have: your utility bills.

By looking at when and how your building uses natural gas, propane, hot water and electricity, we can begin to determine whether producing heat and power together could reduce energy costs and make better use of the fuel your building already consumes.