Active Pilot Programs and Demo Projects

Air-to-Water Heat Pump Field Study

About the Pilot

An air-to-water heat pump (AWHP) is an electric heating system that pulls heat from the outside air and transfers it to water pipes delivering heat to radiators and in-floor radiant systems, doing the work a boiler or geothermal system would normally do. They can operate at up to 500% efficiency and can work in tandem with a backup boiler, saving substantial amounts of energy and potentially reducing energy costs. Air-to-water heat pump systems have been used in Europe for years and are already gaining traction in the Northeast.

Project Timeline: October 2023 - September 2026
Customer Segment: Single-family Residential, Multifamily Residential

White outdoor HVAC unit with two circular fans on a concrete pad, beside a wooden-clad house with sliding doors and a paved patio.

Demonstration Project Objectives:

Demonstrate the impacts of AWHPs in three single family buildings and one multifamily building in Wisconsin including both retrofit and new construction applications. This will include a combination of combined domestic hot water and space heating, cooling, and load shifting using a storage tank and controller.
Define key characteristics (i.e., climate zones, age, fuel type, level of weatherization, hydronic distribution emitter type, and size) that make a home a promising candidate for an AWHP and identify high-opportunity archetypes for AWHP.
Identify the installation barriers for AWHP in Wisconsin, including potential supply chain issues.
Understand the comfort impacts of AWHP as retrofits to existing hydronic heating systems including whether the systems can provide both sufficient heat and hot water.
Document the electricity consumption, backup fuel consumption, and system efficiencies of AWHP. Analyze the impacts to these factors as compared to baseline space heating sources.
Investigate the load shifting potential of smart AWHP systems with storage tanks.
Meter performance before and after installation and model the operations of the proposed AWHP using building energy modelling software to estimate the expected savings from the installation.
Document system failures, changes to operating parameters, and adjustments required throughout the monitoring of the system.
Quantify costs associated with AWHP systems and retrofits, including product, installation, and operating and maintenance costs.
Understand the perspective of the following stakeholders through surveying:
- Users: ability of the equipment to meet user needs and provide a good customer experience.
- Installers: installation lessons learned, technology limitations, and training needs.
- Builders: installation lessons learned, sales pitch for technology to buyers.
- Determine any field limitations and opportunities of the technology.
- Draft a TRM workpaper to support eligibility of AWHP as a prescriptive measure within the Focus on Energy portfolio.

Demonstration Project Updates

The Research Team completed the installation and monitoring of the AWHP systems at the multifamily and three single-family sites. All four sites are in the data collection phase until September 2026.

Questions?

For more information, contact Cynthia Segura at cynthia.segura@focusonenergy.com.