Midea - Plug-and-play Heat Pumps for Multifamily Buildings
New York City, United States · 2022 · Midea, New York City Housing Authority, New York State Energy Research and Development Authority, New York Power Authority (competition context)
The PWHP has been deployed in pilot and early-scale installations within New York City Housing Authority housing stock under the Clean Heat for All initiative, demonstrating the feasibility of unit-level electrification in dense multifamily buildings. The system reduces reliance on centralized fossil-fuel heating by enabling localized electrification through plug-in heat pump units. This approach allows housing authorities to test scalable decarbonization strategies without requiring full building retrofits or tenant displacement. The program is being used as a demonstration pathway for large-scale building electrification in cold-climate urban environments, with ongoing monitoring supported by New York State Energy Research and Development Authority. At a systemic level, the PWHP represents a procurement-driven innovation model: public sector demand is shaping the development and adoption of compact, cold-climate heat pump technologies suitable for constrained urban housing conditions.
Highlight
A window-mounted heat pump that enables rapid electrification of existing apartment buildings without major renovations, making clean heating and cooling accessible to millions of urban residents.
Extended Description
Buildings are responsible for a significant share of urban greenhouse gas emissions, yet electrifying existing multifamily housing remains one of the greatest challenges for cities. Many apartment buildings—particularly affordable and public housing—depend on centralized steam, gas, or electric resistance heating systems that are expensive to replace. Conventional air-source heat pumps usually require exterior units, refrigerant piping, electrical upgrades, and major renovations, making large-scale retrofits costly and disruptive.
To address this challenge, the Clean Heat for All Challenge was launched in New York by NYCHA, NYSERDA, and NYPA, inviting manufacturers to develop innovative heating solutions specifically designed for existing apartment buildings. Midea responded with the Packaged Window Heat Pump (PWHP), a modular system that can be installed through existing window openings with minimal modifications to the building.
The PWHP integrates heating, cooling, air handling, and condensate management into a single self-contained unit. Unlike conventional split heat pumps, both the indoor and outdoor components are incorporated into one window-mounted appliance, avoiding the need for conventional refrigerant piping, separate external compressors, or extensive construction work. The unit operates on standard 120V / 15A residential electrical circuits, making it compatible with much of the existing housing stock without requiring costly electrical upgrades.
Technically, the system is a cold-climate air-source heat pump using an inverter-driven vapor injection compressor capable of maintaining heating performance even during harsh winters. It uses the lower-global-warming-potential refrigerant R-32 and combines heating and cooling in a single appliance, replacing separate window air conditioners and conventional heating systems.
A key innovation is not simply the heat pump itself, but the deployment model. By allowing apartment-by-apartment installation, the PWHP enables building owners and housing authorities to electrify heating incrementally rather than waiting for expensive whole-building retrofits. This reduces installation time and disruption to residents while lowering barriers to deployment across existing multifamily housing.
Building on the same installation-light philosophy, Midea has also introduced the PortaSplit, a portable split-system heat pump designed for renters, temporary housing, heritage buildings, and other locations where permanent structural modifications are difficult. It combines indoor and outdoor units connected by a flexible refrigerant line that can be installed without conventional wall penetration. While the PWHP addresses large-scale multifamily electrification, PortaSplit extends the concept of easier-to-install heat pumps to a broader residential market.
Together, these technologies represent a broader shift in building decarbonization: rather than focusing solely on improving heat pump efficiency, they rethink how heat pumps can be deployed in existing cities, making electrification more practical in buildings that have traditionally been difficult or expensive to retrofit.
Demonstrated metrics
Maintains 100% heating capacity at 5°F (-15°C) with a Coefficient of Performance (COP) of up to 2.0.
Certified to operate in outdoor temperatures down to approximately −13°F (-25°C).
Provides up to 61.5% annual energy savings compared with conventional window air conditioners.
Operates on standard 120V / 15A residential electrical circuits, reducing the need for electrical upgrades.
Combines heating and cooling in a single appliance, replacing separate window AC units and electric resistance heaters.
Rapid window-based installation substantially reduces retrofit complexity and installation time compared with conventional mini-split heat pumps.
Uses R-32 refrigerant, reducing refrigerant-related climate impacts compared with higher-GWP alternatives.
Real impact
The PWHP demonstrates a practical pathway for decarbonizing one of the most difficult segments of the building sector: existing multifamily housing. Rather than requiring costly whole-building renovations, apartments can be electrified individually with minimal disruption to residents. The Clean Heat for All initiative has already influenced the HVAC market by creating demand for products specifically designed for older urban buildings, encouraging manufacturers to develop compact, cold-climate heat pumps that prioritize ease of installation alongside high efficiency. The approach provides a scalable model for public housing authorities, affordable housing providers, and cities seeking to reduce greenhouse gas emissions while improving indoor comfort, lowering energy costs, and increasing resilience to both extreme cold and heat.
Implementation location & date
New York City, United States. Developed through the Clean Heat for All Challenge, launched in 2022. Pilot installations began in NYCHA public housing in 2023, with evaluation and early-scale deployment continuing through the mid-2020s.
Similar cases elsewhere
Gradient (US) develops window heat pumps for multifamily housing, while Innova (Italy) offers through-wall heat pumps without external units.
Sources
https://www.mideacomfort.us/packaged.html
https://www.nyserda.ny.gov/All-Programs/Room-Heat-Pump-Program