Mini-Split & Air Source Heat Pump Education

Air source heat pumps, sometimes referred to as mini-splits, are an energy-efficient electric heating and cooling system that can be used to heat and cool either part, or all, of your home. See below to learn more about this technology, including how it works, financial incentives available, ways to prepare your home for installation, and more.

Advantages of Heat Pump Technology:

• Air filteration
• Energy Efficient (Many available systems are capable of an average efficiency of 300% throughout the course of the heating season)
• Provide both heating and cooling
• Powered by electricity
• Low carbon emissions (especially for HG&E customers due to HG&E's high renewable and carbon-free electricity supply)
• Ability to heat and cool individual rooms rather than an entire house (when installing mini-splits)

How Much Does it Cost to Heat with a Heat Pump Compared to Other Heating Systems/Fuels?

There are many factors that contribute to your annual heating costs, such as the efficiency rating of your heating system, the efficiency of your heating distribution system, fuel rates, etc. The chart below provides information on the annual cost to heat with heat pumps compared to other heating systems to help give some insight into average costs for various fuels/heating systems.

Please Note: The chart below assumes the ducted heat pump and the ductless mini-split heat pump have no electric resistance elements built into the system. While it is possible to install electric resistance elements as part of a heat pump heating system, this can increase the annual heating costs. However, it is also possible that installing electric resistance elements, such as electric strip heat, can reduce the system' installation cost.

However, if you would like to make a more detailed comparison, we have developed a Heating Cost Comparison Tool where you can adjust various factors such as the efficiency of the system, fuel rates, etc. We have both an online calculator available in Google sheets, and a downloadable calculator created in Microsoft Excel.

Downloadable Heating Cost Comparison Tool: Click here to download the Excel version of the heating cost calculator.
Online Heating Cost Comparison Tool: If you would like to use the online calculator in Google Sheets, click here to get started. After you click the link, - press 'make a copy' to open to tool in your web browser. (You will need to be logged into your Google account to use to tool.)

Annual Heating Cost Comparison of Different Heating Fuels/System Types:*

(This chart is for heating costs only; any installation or system upgrade costs are not included.):

Lifetime Heating Comparison by Fuel Type:*

(Installation Cost and heating costs over 15 years):

*Notes and Assumptions Regarding the Above Charts:

• It is assumed that the Ductless Mini-Split Heat Pump and the Ducted Heat Pump have no electric strip heat or electric resistance elements as part of the system. Installing electric resistance elements can increase annual heating costs.

• Electric rate based on HG&E's average residential electric rate of $0.14/kWh

• Natural Gas rate based on HG&E's average residential natural gas rate in 2021 of $1.16/therm

• Heating oil rate based on Massachusetts average residential heating oil price from 2020-2021 of $2.76/gallon

• Propane rate based on Massachusetts average residential propane price from 2020-2021 of $3.05/gallon

• Ductwork is generally assumed to have an average distribution efficiency of 70% with the exception of the new 95% efficient gas furnace, which is assumed to have a distribution efficiency of 90%. Hydronic systems (boilers) are assumed to have an average distribution efficiency of 90%.

• Assumed annual home heating requirement: 80 MMBTU/yr

Financial Incentives Available:

• Residential Incentives: Please review our heat pump and mini-split incentives webpage for more information
• Commercial Incentives: HG&E provides financial assistance at 0% interest for the installation of qualifying heat pumps through the Commercial Energy Conservation Program

How Much Does a Heat Pump System Cost to Install?

According to data from MassCEC, the average price per ton for a heat pump in Hamden County as of September 2021 is $3,3100 per ton. Therefore, whole-home heat pump systems (capable of supplying 100% of a home's heating requirements) typically have higher installation costs than conventional heating systems with average installation costs ranging from $15,000-$20,000+. However, heating costs can be much lower than a conventional oil, propane or electric resistance heating system. See the section below for more information.

How Does an Air Source Heat Pump System Work?

Air source heat pumps consist of two main components: an indoor unit and an outdoor unit. Refrigerant cycles between the indoor and outdoor units, carrying heat from one location to another, similar to how a refrigerator operates. In the summer, heat is moved from inside the home to outside, blowing the remaining colder air back into the house. In the winter, they reverse operation, extracting heat from the outdoor air and transferring it into the home.

Ducted, Ductless or Both?

Heat pumps can either be connected to ductwork, or, they can be installed without the need for ducts. These 'ductless' systems are often referred to as "mini-splits" and typically consist of one or more wall-mounted indoor units connected to an outdoor unit. The main advantages of mini-splits are their small size and flexibility for zoning (heating and cooling individual rooms). Many models can have as many as four indoor units (for four zones or rooms) connected to one outdoor unit.

Will a Heat Pump Work During Holyoke's Cold Winter Temperatures?

Because refrigerant has a low boiling temperature, many heat pump models can continue to provide heating even during cold winter temperatures. If sized correctly, they can even be used as a home's primary, or only, heating system. The Northeast Energy Efficiency Partnership (NEEP) has published a list of verified Cold-Climate heat pump models that are capable of operating at an efficiency of 175% when the outdoor air temperature is 5°F. Average winter temperatures in Holyoke fall below 5 degrees for only about 44 hours each year, with a low of negative 8.2 degrees. Therefore, if you are looking for a heat pump that can operate year-round in Holyoke's climate, it is recommended to choose a heat pump that is rated to provide heat down to -9°F.

Weatherizing Your Home Before Installation

Consider preparing your home for the heat pump before it is installed by first air-sealing and insulating to a proper extent. Having a tighter, more insulated home not only reduces annual heating costs, but might also allow you to buy a smaller heat pump system than you would have needed otherwise. HG&E provides free home energy audits to customers which determine cost-effective weatherization improvements you can make to reduce your annual heating and cooling costs. You can also take advantage of Holyoke's weatherization incentives to help cover the costs.

Understanding Common Heat Pump Ratings

System Size and Output Capacity:

The amount of heating and cooling that a heat pump system can provide depends on its size, or "output capacity". Smaller heat pumps can be used to heat individual rooms or spaces. Larger, whole home systems may have multiple indoor units connected to one or more outdoor units. The output capacity of a heat pump system can vary depending on the outdoor temperature. The NEEP Cold-Climate Air Source Heat Pump List provides the output capacity at various outdoor temperatures down to 5 degrees F.

HSPF:

This is the average annual heating efficiency of the air source heat pump system. The HSPF indicates how much heat is produced for each watt of electricity that the system consumes. For example, if a heat pump has an HSPF of 10, this means that the system will output an average of 10 BTUs of heat for every watt consumed throughout the heating season. Ensuring the system has a high HSPF will help lower your annual heating bills.

SEER:

This is the average annual cooling efficiency of the heat pump. The SEER rating indicates how much cold air is produced for each watt of electricity that the system consumes. A higher SEER rating will reduce your cooling costs over the cooling season.

EER:

The EER rating is the cooling efficiency of the system when its specifically 95 degrees outside.

How to Shop for a Heat Pump

When choosing a heat pump installer, its a good idea to get quotes from multiple contractors, as installation costs can vary widely depending on who you work with. But, be sure your installer has experience installing heat pump systems as they are a more complex technology than conventional heating and cooling systems. One way to help ensure this is to check to see if the installer has a manufacturer's certificate of training. The Northeast Energy Efficiency Partnership (NEEP) has provided an Air Source Heat Pump Buying Guide to help you choose the right system for your needs. See pages 13 and 14 of the guide for best practices for choosing a heat pump system and questions to ask a contractor to ensure they are experienced with installing this system type.

Resources on Proper Heat Pump Operation

How to Use your Ductless Heat Pump: Guidance from Efficiency Maine about the best practices for maintenance and upkeep of a heat pump.
Who knew? 8 ways NOT to use a heat pump: Read this article from Efficiency Vermont for information on common misconceptions related to heat pump operation.

Further Resources:

Northeast Energy Efficiency Partnership’s Air Source Heat Pump Buying Guide and MassCEC’s Heat Pump Guide are great resources to review to learn more about how air source heat pumps work, which design is right for your home, size and ducting options, and more!

Questions?

Contact Sophie Theroux
Energy Efficiency Coordinator
Tel: (413) 536-9382
Email: stheroux@hged.com