Energy savings from dual-fuel controls optimization

"Controls, controls, controls."

Many say those are the biggest keys to success when it comes to heat pump installations. Controls are crucial to a resident's experience of new technology. Even if a solution has the potential to be cheaper, more efficient, and more eco-friendly, those benefits fall off when poorly implemented controls get in the way.

In Minnesota, dual-fuel heating systems can be a cost-effective way to move homeowners partially away from fossil fuels. Adding an efficient air-source heat pump to an existing gas furnace is almost always cheaper than replacing the system entirely, and the ability to shift to backup fuel offers more flexibility and can lower operating costs for homeowners on the most frigid days.

However, leveraging this flexibility is often confusing in practice.. The combined jumble of switchover temperatures, indoor droop settings, and setback recovery strategies introduces a dizzying array of schemes that often confuse users and can jeopardize intended energy or economic savings from dual-fuel systems.

This research, conducted in partnership with CEE, builds on previous studies of dual-fuel performance and controls strategies in the Midwest. This study will result in clear, practical guidance for utilities and contractors to understand the tradeoffs between economic and environmental priorities at both smaller and larger scales, influencing future educational campaigns and utility programs.

This research was made possible by a grant from the Minnesota Department of Commerce, Division of Energy Resources through the Conservation Applied Research and Development (CARD) program, which is funded by Minnesota ratepayers.