Hallowell Acadia Is Revolutionizing the Heating Industry

Duane Hallowell stands behind the Acadia, a revolutionary air-source heat pump that works down to -30° F. Photo: Courtesy Duane Hallowell

How do you heat and cool your home? Do you have both a furnace and an air conditioner? What if you could install a single, highly efficient, and environmentally sound system to handle both heating and cooling?

The Acadia, designed and built by Hallowell International, is a revolutionary, next-generation, air-source heat pump — the first that functions efficiently in cold climates down to -30˚F. Even residents of Canada and New England can enjoy comfortable indoor temperatures year ’round without the use of fossil fuels.

Blue Planet Green Living (BPGL) spoke with Duane Hallowell, president and co-founder of Hallowell International, to learn about the latest innovation in heat pumps. We began by asking him what prompted the development of the Acadia. — Joe Hennager, President

UPDATE 3/27/11: Our efforts to contact Hallowell International have been unsuccessful for the past six months. We have heard reports that the company is out of business, though we have not personally been able to verify this. — Julia Wasson, Publisher

HALLOWELL: My co-founder, David Shaw, worked as a senior compressor designer for one of the largest HVAC [heat, ventilation, and air conditioning] companies in the world. He had spent his life working on thermodynamic principles and simpler ways to do things better.


In the (1990s, an electric utility approached him, asking for a better solution for air conditioning and an air-source heat pump that would work well in northern climates. David suggested using a geothermal system.

The utility said, “That’s not the answer we’re looking for. We’ve been trying to promote geothermal systems very heavily with incentive programs and rebates, but not enough people put them in.”

The upfront cost of the wells or the ground loops made the installation too complicated or costly. On the other hand, air-source heat pumps are simple to install and remain the most dominant form of heating in southern climates. In northern climates, they rapidly lose their ability to efficiently heat below freezing conditions.

David said, “That’s not a very difficult problem to solve. An air-source heat pump is more than capable, but you’d have to adjust your way of thinking about it.”

BPGL: What did he mean by that?

HALLOWELL: Historically, heat pumps were primarily designed as air conditioners. For heating, they’re really not suited below 30 degrees F, or below freezing conditions. Your toaster, oven, or electric water heater uses electric energy very inefficiently — to produce heat. Heat pumps, geothermal systems, and Acadias use a refrigeration practice to take that same electric energy and simply transfer heat, not produce it. Since the 1950s, heat pumps have been used in numerous applications and today are known to provide efficiencies up to 500%. But the ability to transfer heat efficiently and comfortably got lost below freezing conditions.

David’s solution to the problem was to use a basic, cost-effective, air-source heat pump but put it on steroids! Customers in northern climates wouldn’t have the high, up-front installation costs of geothermal, but we had to make the heat pump work better. Very simply, we created and patented a concept that would allow the system to continue to absorb heat in northern climates.

Boosted Compression

BPGL: How does it work?

HALLOWELL: We use a secondary compressor and sub cooler, which essentially works like a turbo booster. We call it, “boosted compression.” You really have to look at the usable energy down to absolute zero. There’s actually plenty of heat in the air, you just have to compound it, compress it, and put it in the house.

It’s no different than the concept of your refrigerator freezer, when you think about, “Is there usable energy in that air?” In a freezer, you’ve got frozen pizzas and Popsicles and everything else. Yet, if you feel the back, it’s warm. The compressor takes the energy from inside that freezer space and transfers the heat into the air outside the freezer.

Alternatives  to Fossil Fuels

BPGL: Was there an environmental motivation behind the invention of the Acadia?

HALLOWELL: When I was introduced to David Shaw, I didn’t think a lot about energy efficiency, being green, or environmental concerns. I was starting my career, and I was concentrating on design and manufacturing.

Then I started seeing all the problems. Electric utilities were talking about some pretty taxing issues on the electric grid. They said, “We really need to reduce these peak loads — both from air conditioning and heating — in so many different parts of the country.” Each state is just riddled with problems. So it was a mad dash to increase efficiency on both heating and cooling.

At the same time, fossil fuel costs started rising very rapidly. And environmental concerns came in very strong. I was contacted by groups like Rocky Mountain Institute, the American Council for an Energy-Efficient Economy (ACEEE), the National Rural Electric Cooperative Association, and major utilities all across the US that were trying to encourage our growth. They said, “If you can truly do this with an air-source heat pump, you’ve just fixed a myriad of problems that we’ve been trying to address for many years.” Until the Acadia, the only answer had been geothermal heat pumps. 

Inside the Acadia air-source heat pump system. Diagram: Courtesy of Duane Hallowell

In 2008, everyone said, “What is there besides oil? I’m not going to gamble the heating system in my house on the unstable and unpredictable fossil fuel market for the next 20 years.”

BPGL: What alternative heating systems were you seeing in New England at the time?

HALLOWELL: We saw a lot of innovation coming in very rapidly, but it was mainly along the lines of pellet stoves and minor steps toward improvements to fossil fuel systems. People started taking notice of heat pumps and asking, “Do we have air-source heat pumps that work in northern climates?”

When we designed the Acadia, we asked, “What’s wrong with a standard air-source heat pump in northern climates?” Efficiency was, I think, number seven on the list. Reliability was absolutely number one. Comfort was number two.

With our patented boosted compression technology, the Acadia fixed what had been the issue. We were kind of pioneering in the northern climates. Our first work was done strictly with electric utilities. And it immediately went into the mainstream market, replacing fossil fuel systems throughout New England.

BPGL: How is the Acadia different from a geothermal heat pump system?

HALLOWELL: The Acadia is categorized as an air-source heat pump. A geothermal is called a ground-source heat pump. So when you transfer heat, you’re taking energy from one place and putting it in another; with the Acadia that energy transfer is via the air, and with geothermal it is from the ground. A heat pump is nothing more than an air conditioner that can reverse direction. When you’re air conditioning, you’re taking energy — heat — from inside your house and transferring it outside. And when heating, you are doing the opposite: pulling the heat from the outside air and transferring it into the home.

Air-source heat pumps occupy a large percentage of heating systems sold in the US. But until the Acadia, they were not feasible in northern climates due to the loss of efficiencies, comfort, and reliability as temperatures drop.

High Performance Below Freezing

BPGL: So, the Acadia can keep a house comfortably warm even when it’s 20 degrees below zero (Fahrenheit)?

HALLOWELL: A conventional air-source heat pump only works down to freezing conditions. And that was the significance behind the Acadia. We actually rated the system to 30 degrees below zero, with the same efficiencies that you see with conventional air-source heat pumps in milder conditions. This is due to our patented technology, the “secret sauce” behind the Acadia.

BPGL: How do you control frost buildup?

HALLOWELL: As it gets colder outside, there’s less relative humidity in the air. It actually gets easier for us to handle frost buildup. The toughest part of the winter for us, or for any air-source heat pump, is the conditions between 25 and 40 degrees. That’s when the relative humidity in the winter air is highest. That’s when you’re going to accumulate frost.

The engineering into the Acadia really fell into the 25 to 40 degree range. The greatest penalty associated with any air-source heat pump is going to be its necessity to defrost. So we said, if we’re going to peak our efficiency of the Acadia for winter heating conditions, let’s design it around the defrost.

The Cooperative Research Network, which is the research branch of the National Rural Electric Cooperative Association, studied us in seven states alongside conventional air-source heat pumps. We defrosted approximately 50% less than the conventional air-source heat pump we were studied against, which was remarkable in itself. The Acadia also used less than 5% supplemental heat compared to over 40% used by the conventional heat pump.

Comparing Costs

BPGL: How does the cost of using the Acadia compare with other heating systems?

HALLOWELL: It varies. The lower the electrical rate, the more favorable the Acadia is — especially over fossil fuel. Here in Maine, we pay 15 cents per kilowatt hour. With current fossil fuel prices, the Acadia provides a 42% savings on average. When you go out to areas where you have a more favorable electric rate, it’s even better. The national average, I believe, is 11 cents per kilowatt hour right now. At 11 cents per kilowatt hour, you’re probably at 55% or greater savings over fossil fuel.

Over natural gas, I’m showing a 25% savings. And you’ve got to remember, natural gas is the closest thing to competition that we have. If a customer doesn’t have natural gas in their town, and they use propane — which is the case in a lot of towns and rural communities — right now at 12 cents per kilowatt hour, that’s a 50% savings with an air-source heat pump. If you were to compare the Acadia to number 2 heating oil or propane, the savings would be even more than that. It’s all case-specific based on electric rates.

BPGL: What does it cost to install an Acadia?

HALLOWELL: The average cost is $10- to $14,000 installed, for the labor, equipment, and duct modifications. If you’ve already got central air conditioning, it can be less than that, because the modifications are relatively minor. Normally, it’s a pretty easy installation.

If you’re changing out a perfectly good system, you’d have to make an investment. But when it’s time to replace your system, what would you have spent on the Acadia compared to a conventional system? For most of our contractors, if they’re doing an upgrade, it costs anywhere from $5- to $7,000 for a retrofit. That means, they’re putting in another natural gas furnace and a central air conditioner. So, if we assume that you would have spent $7,000 to do that, you’d have to be making up that difference.

In new homes, such as McGuire/Fort Dix Air Force Base in New Jersey, which is in the process of installing 2,000 Acadia systems in all of their base housing, they’re actually saving $3,000 per home by not putting in natural gas infrastructure. Also, your insurance may drop by not having gas within your home. You don’t need to install a direct vent. There’s no fuel storage. There’s no chimney. There are a lot of “little” savings that add up.

Tax Credits, Incentives, and Rebates

BPGL: Are there any 2010 energy tax credits people can take advantage of with an Acadia?

HALLOWELL: I’ve spent the last two years working on a new federal standard. Our senators here in the state of Maine actually helped us fight with the Department of Energy [DOE]. On November 23, 2009, the DOE issued a new federal standard recognizing boosted compression, or three-stage heat pumps, which had never been done before. Now consumers installing a qualifying three-stage heat pump can get the $1,500 tax credit that would be available to any other customer buying an air-source heat pump.

In 2010, the 2- and 3-ton Acadia models qualify for the tax credit listed under Energy Star. Even without the federal standards in place, the electric utilities have come in with huge support. In some parts of the country, we see rebates up to $4,000 per Acadia. Here in Bangor, Maine, we have a $1,600 rebate for every Acadia that goes in. Each electric company will apply its own rebates.

You can find electric utility rebates at DSIREUSA.org, which is a federal database. Utilities have also added their incentive and rebate programs onto that website.

BPGL: That should make it easy for consumers to find and apply for rebates.

HALLOWELL: When it comes to federal paperwork that needs to be filled out, a lot of people get lost in translation, trying to figure out whether their system qualifies. Trying to make it simple for everybody becomes a little problematic, especially when you get into windows and insulation, and things like that.

BPGL: Does Hallowell provide guidance to help people understand how to apply for the rebates?

The Acadia installs outside the home and connects to existing ductwork. Photo: Courtesy Duane Hallowell

HALLOWELL: Absolutely. Our dealer training and customer service go beyond the call of duty, simply because we are talking about those things. We’re talking about the building envelope and weatherization, and we continue to help customers take the right first steps, even before looking at an Acadia. This is the same recommendation that I’d make to anyone: Look at weatherization first.

Everyone defaults to the low-cost BTU or the smarter system, but you should first pay attention to the home itself — weatherization, insulation practices, doors, windows — these are the cornerstones to efficiency— and take advantage of those tax credits first.

Getting people to do it is another story. So, as we’re putting in an Acadia, we come in on an engineering angle and say, “If you spend $1,000 on insulation, we could actually downgrade your Acadia system so you could go to the next smallest model, which is $1,000 less. Then it potentially becomes a wash.

We try to work with our customers to take full advantage of energy efficiency, but also to talk with them about water conservation measures and what that means. We help people get used to certain things that don’t disrupt their standard of living. People like technology, but they don’t want change.

We also spend a lot of time with our dealers. In order to become an Acadia dealer, they have to go through a rigorous training that encompasses the entire home. That’s where we feel we’re making the greatest contribution to the customers themselves.

BPGL: How widespread is use of the Acadia?

HALLOWELL: We’re established in 38 states here in the US and all territories of Canada, with infrastructure, dealer networks, and wholesalers carrying the repair, parts, and products. We support over 8,000 dealers across the US.

Typically, we’ll go to areas that have the most advantage with their climate, their energy rates, and other variables. It was at my direction not to give a lot of attention to the Midwest, simply because of the favorable geothermal rates there. In other parts of the country, there wasn’t any other option. Up here, in New England, a geothermal system would cost you from $20- to $30,000.

300% Efficient

BPGL: In your advertising, you say the Acadia is 300% efficient — compared to what?

HALLOWELL: To answer that you’d have to understand what a co-efficient of performance is. A coefficient of performance is a measurement of usable energy. Electric heat is really your baseline and is 100% efficient. That’s called a coefficient of performance of one. You put power in, you get a certain amount of BTUs out — that’s 3.412 BTUs to get a little technical — for every Watt of energy that you’re delivering off the power source of the house. That rule applies whether that power is coming from solar or wind or right off the grid.

You use a lot of energy to provide heat. When you look at a boiler or furnace, it’s actually less than 1: between 85 and 95% efficient. The reason people use fossil fuel over electric heat is the energy rates. Even if it’s less efficient, fossil fuel might be cheaper.

When it comes to the heat pump, we’re actually not using the energy to create the heat. So a coefficient can be higher. You’ll see geothermals that say they’re 300 to 600% efficient. In other words, for that one Watt of energy that you’re putting into it, rather than getting 3 or 4 BTUs out of it, you’re getting 12-, 15-, or 20,000 BTUs. Unlike electric heat which uses energy to create heat, we take that same energy to transfer heat. This transferred heat is providing 3 or more times the BTU’s that were produced by electric heat at 100% efficiency, hence the 300% rating

BPGL: Is the Acadia as efficient at air conditioning as it is at heating?

The Acadia works as both an air conditioner and a furnace. Photo: Courtesy Duane HallowellHALLOWELL: It’s a simple flick of a switch to give you high-efficiency, two-stage air conditioning with the Acadia. The electric utility has what’s called a Seasonal Energy Efficiency Ratio, or SEER, that’s applied to air conditioners. The higher the number, the more efficient it is. Window air conditioners and the older central air conditioning units were typically anywhere between a 7 and a 10 SEER. The Acadia is a 15.

There are a ton of great air conditioners out there right now. But the discrepancy still remains by that single flick of a switch: Who can also work well in heating at conditions that we see across the US in northern climates?

BPGL: About how many units do you have out?

HALLOWELL: About 4,000 systems. We’re a very interesting product and company. We’re a very caring company, too, and I think it’s because we started out as an engineering company; it wasn’t about the sale. We’re very, very passionate about not only global warming, but also about fixing a broken-down infrastructure and paying closer attention to our dealers.

In the heating and cooling industry, the first customer we see isn’t the residential homeowner or the commercial property owner, it’s the dealer himself. Dealers are asking for simplicity in design and serviceability. The need for change in the HVAC industry has come in very strong and very rapidly, but there’s a lack of education and certification programs for dealers.

I’m very proud of my dealers. From a company standpoint, designing and bringing in new applications, we’re always looking at how to simplify the process. I think everyone else should follow suit to that, in support of better energy practices, of course.

Supporting Infrastructure

BPGL: What if a consumer installs an Acadia and has trouble with it? Are there enough service people who know how to fix it?

HALLOWELL: The beauty of an Acadia is that it works with an existing infrastructure — the HVAC industry. And if you open up your phone book in any part of the world, you’ve got air conditioning contractors. That’s very significant.

A lot of new technology has come in the last couple of years. We’re seeing overseas companies being better innovators and providing better technology than what we’re seeing here in the US. I get asked, “What about a fuel cell? What about a co-generation system? What about pellet stoves? What about this and that?

And I say, “Even if you could buy one, if it broke, who would fix it?” Even if the innovation is out there, and it answers everybody’s prayers, if it broke, could it get fixed?

Even in northern climates, you could install an Acadia, and if it broke, you’d have a phone book of service contractors who could actually repair it. And you’d have wholesalers and distribution locations that were always carrying the repair parts and making recommendations for trained Acadia contractors to use. We didn’t have to build any of that. So, as the infrastructure was already in place, it actually greased the skids to the release of the Acadia.

As Green as the Electric Grid

BPGL: Would you describe the Acadia as a “green” heating and cooling system?

HALLOWELL: We’re as green as the electric grid. In certain parts of the country, where there’s gas, nuclear, or coal use, that’s not so green. But in other parts of the country, we’ve got great wind power, hydro, tidal, earth or other clean renewable energy that can be used to power the Acadia. In those places, the Acadia is very green.

The Acadia doesn’t need to use any fossil fuel. We have a number of customers who power their Acadia solely from a solar panel or offset their electric bill every month with a wind turbine. It’s those types of stories that really fuel my fire.

You have to get people to think about the different ways of generating electric energy. In Manitoba, they use 98% hydro power. That electric energy being provided is very, very clean. We don’t have trucks running across the road delivering fuel into homes. In a time when we are seeing the icecaps melt, we all need to be concerned with things like that.

To me, we’re in the Energy Age. We got used to fuel being cheap. But change is coming rapidly for many reasons. With the Acadia, people are finding a choice away from fossil fuel, and that’s definitely what my objective was. I sleep very well at night.

Joe Hennager

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