HP-Flex is an open-source building energy management system that controls the operation of heat pumps (HPs) and other equipment in small/medium commercial (SMC) buildings to provide load flexibility (LF) while meeting occupant needs and minimizing operating cost.

The HP-Flex project team, led by Lawrence Berkeley National Laboratory, is developing open-source control algorithms for demand-flexible heat pumps, testing these algorithms in a handful of SMC buildings in disadvantaged communities, and incorporating these findings in educational curricula to train the next generation of engineers and technicians on quality design and installation of demand-flexible heat pumps.

The goals of the project are to promote the large-scale deployment of replicable, demand-flexible heat pump installations in SMC buildings, and increase benefits to both individual building owners and the distribution grid compared to standard HP installations. The research findings will be publicly shared through documents and other technology transfer activities hosted on this site and on the California Energy Commission website.


The Need for HP-Flex

The need for HP-Flex is driven by California’s ambitious goals for renewables integration (SB 100) and heating electrification, which are causing the state's electrical grid to experience more pronounced load fluctuations (e.g, the duck curve) and new winter morning system peaks. These challenges require buildings to modulate their demand in response to the needs of the grid, going beyond traditional demand response (summer load shed) to include continuous load management that meets several grid needs:

  • Shape: response to dynamic pricing or a grid time-of-use (TOU) signal to provide a specified power profile, minimizing energy costs during peak TOU periods in all seasons.

  • Shift: a dispatchable type of LF that is composed of a “take” event and a “shed” event that occur within a few hours of each other.

  • Shed: reduction of peak load for defined, multi-hour events called a few times per year, either in summer or winter.

  • Shimmy: a fast-acting modulating load, such as load following a five-minute wholesale market signal.

As described in the 2019 California Energy Efficiency Action Plan, “electrification of space and water heating with highly efficient technologies, coupled with strategies to shift energy consumption in real-time, are key to reducing greenhouse gas (GHG) emissions from buildings." The Action Plan also states, as part of its goal to expand energy efficiency in low-income and disadvantaged communities, that “More work is needed to remove financing barriers, and to develop the local workforce needed to implement clean energy solutions.”

An Overview of the HP-Flex System

The HP-Flex system, pictured below, includes new optimization software and equipment interfaces that collectively optimize HP operation, while being extensible to manage equipment such as refrigeration, water heaters, batteries, and thermal storage. HP-Flex’s standardized, modular design allows easier configuration than existing systems, thus enabling a more cost-effective and reliable control for SMC applications. HP-Flex will minimize energy bills and optimize load flexibility using a variety of building equipment such as heat pumps, air conditioners, and commercial refrigeration, as well as Distributed Energy Resources (DERs) such as battery and thermal energy storage systems.

HP-Flex system overview and research objectives

RESEARCH OBJECTIVES

  • Develop an advanced, integrated, open-source control system to cost-effectively provide energy optimization and load flexibility to heat pumps in SMC buildings.

  • Verify that HP-Flex integrated in SMC buildings can meet the following criteria:

    • Achieve a 20% reduction in site peak energy costs compared to a SMC heat pump with scheduled thermostatic control.

    • Provide 50% load shed during summer or winter peak-load events.

    • Provide 20 kWh of daily load shift capacity for a typical SMC building during the shoulder seasons.

    • Provide “shimmy” services equivalent to 10% continuous response of average baseline load.

    • Enable 25% of the baseline load to respond to dynamic prices to shape daily load profile in summer and winter

    • Meet a payback time of < 2 years.

  • Integrate and control a thermal energy storage system with a SMC heat pump.

  • Develop educational curricula to train engineers and technicians on the design, installation, and maintenance of load-flexible HP systems.


KEY RESEARCH ACTIVITIES

Benefits to California IOU Ratepayers

This project will result in the ratepayer benefits of greater electricity reliability and lower costs. It will also result in direct benefits to the site host and to the local distribution grid. However, the greatest benefits from the project will likely come from the improved ability to promote deployment of demand-flexible heat pump systems at scale throughout California. As HP-Flex systems are deployed throughout the state, these ratepayer benefits will increase over time.