Delivering Efficient Local Thermal Amenities

Building Efficiency

Release Date:
Project Count:

Program Description:

The projects in ARPA-E's DELTA Program, short for "Delivering Efficient Local Thermal Amenities," aim to reduce the costs for heating and cooling buildings by developing Localized Thermal Management Systems (LTMS). LTMS modify the physical space around the human body rather than the entire building, with significant energy savings for both new and old buildings. Such technologies range from on-body wearable devices to off-body installed systems and provide more options for maintaining occupant comfort within buildings. ARPA-E’s DELTA projects include a broad range of LTMS approaches that potentially enable energy savings of upwards of 2% of the total domestic energy supply and similar reductions in greenhouse gas emissions.

Innovation Need:

Heating, Ventilation, and Air Conditioning (HVAC) account for 13% of energy consumed in the U.S. and about 40% of the energy used in a typical U.S. residence, making it the largest energy expense for most homes. Even though more energy-efficient HVAC technologies are being adopted in both the commercial and residential sectors, these technologies focus on efficiently heating or cooling large areas and dealing with how the building’s net occupancy changes during a day, a week and across seasons. Building operators have to tightly manage temperature for an average occupancy comfort level; but the occupants only occupy a small fraction of the building’s interior. Controlling the entire building to satisfy a small portion of occupied space is energy inefficient. DELTA seeks to save energy by tailoring the thermal environment around the individual rather than over-heating or over-cooling unoccupied space within a building. ARPA-E’s analyses demonstrate that a potential annual savings of at least 15% of total HVAC energy consumption is feasible by using LTMS technologies and widening the overall temperature settings of a building by 4°F. While the DELTA program will focus on technologies for rapid adoption in existing buildings, the long-term vision is that these solutions will improve HVAC system efficacy, making more sustainable energy‐efficient new buildings possible as well.

Potential Impact:

If successful, DELTA technology could increase energy efficiency, reduce emissions produced by powering traditional HVAC systems, and enable more sustainable heating and cooling architectures for energy-efficient building design.


The innovations developed under the DELTA program have the potential to increase energy efficiency, improve overall building performance, and reduce HVAC energy consumption by at least 15%.


The heating and cooling of buildings generates about 13% of the U.S. domestic greenhouse gas emissions. Through improved utilization of energy produced by fossil fuels, with full adoption, DELTA can reduce these emissions by 2%.


DELTA program innovations can help U.S. businesses eventually reduce reliance on tightly controlled building environments, thus enabling radical and sustainable architecture in next generation energy-efficient building designs.


Program Director:
Dr. Jennifer Gerbi;Dr. Marina Sofos
Press and General Inquiries Email:

Project Listing

• Cornell University - Thermoregulatory Clothing System
• Otherlab - Passive Thermo-Adaptive Textiles
• SRI International - Wearable Electroactive Textile
• Stanford University - Photonic Structure Textiles
• Stony Brook University - Electroactive Smart Air-Conditioner VEnt Registers (eSAVER)
• Syracuse University - Micro-Environmental Control System
• University of California, Berkeley (UC Berkeley) - Wirelessly Powered Heating and Cooling Devices
• University of California, Irvine (UC Irvine) - Thermocomfort Cloth
• University of California, San Diego (UC San Diego) - Adaptive Textiles Technology
• University of Maryland (UMD) - Robotic Personal Conditioning Device
• University of Maryland (UMD) - Meta-Cooling Textile