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Building Efficiency

Texas A&M University

SLEEPIR - Synchronized Low-energy Electronically-chopped PIR Sensor for Occupancy Detection

Texas A&M University will develop an advanced, low-cost occupancy detection solution for residential homes. Their system, called SLEEPIR, is based on pyroelectric infrared sensors (PIR) a popular choice for occupancy detection and activity tracking due to their low cost, low energy consumption, large detection range, and wide field of view. However, traditional PIR sensors can only detect individuals in motion. The team proposes a next-generation PIR sensor that is able to detect non-moving heat sources and provide quantitative information on movement. Their innovation relies on the use of an "optical chopper" which temporarily interrupts the flow of heat to the sensor and allows the device to detect both stationary and moving individuals. The team will evaluate several approaches for the chopper, such as new low-power liquid crystal technology with no moving parts. They will apply new signal processing techniques and machine learning to the infrared data, enabling differentiation between pets and people and potentially sleep vs. active states. A central hub accepts wireless data from the sensors and overrides the home thermostat as needed to adjust temperatures and provide up to 30% energy savings to the home.

The Mackinac Technology Company

Retrofit System for Single Pane Glazing

The Mackinac Technology Company will develop an innovative, cost effective, retrofit window insulation system that will significantly reduce heat losses. The insulation system will use a durable window film that is highly transparent to visible light (more than 90% of light can pass through), but reflects thermal radiation back into the room and reduces heat loss in winter. The film will be microporous and breathable to allow air pressures to balance across the window system. The film will be bonded to a rigid frame that can be retrofitted to an existing single-pane glass window. Mackinac's pane assembly will maintain a wrinkle-free appearance over an anticipated 20-year product lifecycle. The system will be fire resistant and lightweight (less than two pounds per square foot of window pane), which will help reduce stress on existing window panes.

Triton Systems, Inc.

New Technology for Single Pane Retrofit

Triton Systems will develop and demonstrate a high efficiency windowpane system that will encourage retrofitting of single-pane windows. Triton's Multifunctional Glazing System (MGS) will potentially provide a better balance of performance with cost and weight versus double-pane insulated glass units. The system combines a nanoparticle-polymer composite film with an insulating layer of a porous material filled with air, to provide thermal insulation. The team will enhance the pane's durability by incorporating a nanocomposite edge seal. The thickness of the MGS will be less than ¼ inch, ensuring its compatibility with most single-pane window sashes as a direct glazing replacement.

United Technologies Research Center

Power Conversion Through Novel Current Source Matrix Converter 

United Technologies Research Center (UTRC) will develop a silicon carbide-based, single stage, 15 kW direct AC-to-AC (fixed frequency AC to variable frequency AC) power converter that avoids the need for an intermediate conversion to DC or energy storage circuit elements. The team seeks to build a device that weighs about half as much as available converters while demonstrating scalability for a broad power range (from kW to tens of MW) and achieving conversion efficiencies greater than 99%. If successful, the UTRC team will produce advances that help greatly reduce energy losses in a range of industrial applications. Industrial drives for electric motors alone account for approximately 40% of total U.S. electricity demand and incorporation of highly efficient variable-frequency drives, based on this technology, can reduce energy consumption by 10-30%. For aircraft power systems, electrical actuators built using this technology can enable longer, thinner, and lighter wings that result in 50% reduced fuel consumption and carbon emissions when compared to current commercial aircraft. The project can also open new possibilities for electric locomotives and ship propulsion, thanks to the reduced weight and complexity of the converter.

United Technologies Research Center

Nano-Engineered Porous Hollow Fiber Membrane-Based Air Conditioning System

United Technologies Research Center (UTRC) is developing an air conditioning system that is optimized for use in warm and humid climates. UTRC's air conditioning system integrates a liquid drying agent or desiccant and a traditional vapor compression system found in 90% of air conditioners. The drying agent reduces the humidity in the air before it is cooled, using less energy. The technology uses a membrane as a barrier between the air and the liquid salt stream allowing only water vapor to pass through and not the salt molecules. This solves an inherent problem with traditional liquid desiccant systems--carryover of the liquid drying agent into the conditioned air stream--which eliminates corrosion and health issues.

United Technologies Research Center

PEOPLE: Platform to Estimate Occupancy and Presence for Low Energy Buildings

United Technologies Research Center (UTRC) will develop a low-cost occupancy solution that combines radar sensing technology with an infrared focal plane array (IR-FPA) to determine occupancy in buildings. The solution will also be deployed as a radar-only residential sensor for true human presence sensing. The radar will detect respiration or heartbeat of non-moving occupants by measuring the radar signal reflections caused by chest movement. The system's machine learning algorithms will allow it to distinguish humans from pets in residential settings and to reduce under-counting errors in commercial deployments. The radar will enable through-wall presence sensing in multiple rooms by a single sensor, reducing the sensor hardware and installation cost on a per square foot basis. The solution aims to address the high cost and failure rate of current presence sensors that are preventing large-scale adoption of occupancy based control of HVAC, lighting, and plug loads.

United Technologies Research Center

Water-Based HVAC System

United Technologies Research Center (UTRC) is developing an efficient air conditioning compressor that will use water as the refrigerant. Most conventional air conditioning systems use hydrofluorocarbons to cool the air, which are highly potent GHGs. Because water is natural and non-toxic, it is an attractive refrigerant. However, low vapor density of water requires higher compression ratios, typically resulting in large and inefficient multi-stage compression. UTRC's design utilizes a novel type of supersonic compression that enables high-compression ratios in a single stage, thus enabling more compact and cost-effective technology than existing designs. UTRC's water-based air conditioner system could reduce the use of synthetic refrigerants while also increasing energy efficiency.

University of Alabama

Quantification of HVAC Energy Savings for Occupancy Sensing in Buildings Through an Innovative Testing Methodology

The University of Alabama and their partners will develop a new testing and validation protocol for advanced occupancy sensor technologies. A barrier to wide adoption of new occupancy sensors is the lack of rigorous and widely accepted methodologies for evaluating the energy savings and reliability of these systems. To address this need, the Alabama team will develop a testing protocol and simulation suite for these advanced sensors. The protocol and simulation suite will take into account eight levels of diversity: 1) occupant profile, 2) building type and floor plan, 3) sensor type, 4) HVAC controls and modes (e.g., temperature and/or ventilation setback), 5) functional testing diversity, 6) deployment diversity (e.g., sensor location), 7) software diversity (e.g., computation at local vs. hub), and 8) diagnostic diversity (e.g., interpret missing data). The regime's simulation tools will take advantage of data analytics with built-in machine learning algorithms to accurately determine energy savings. Technical results from the testing and validation work will support technology to market efforts, including codes and standards updates.

University of California - Irvine

Thermocomfort Cloth Inspired by Squid Skin

The University of California, Irvine (UC Irvine) will develop a dynamically adjustable thermoregulatory fabric. This fabric leverages established heat-managing capabilities of space blankets and color-changing polymers inspired by squid skin that will provide wearers with the unique ability to adaptively harness their own individual radiant heat production. This technology holds the potential to establish an entirely new line of personal apparel and localized thermal management products that could significantly reduce the energy required to heat and cool buildings.

University of California, Berkeley

Rapid Building Energy Modeler - RAPMOD

The University of California, Berkeley (UC Berkeley) and Indoor Reality are developing a portable scanning system and the associated software to rapidly generate indoor thermal and physical building maps. This will allow for cost-effective identification of building inefficiencies and recommendation of energy-saving measures. The scanning system is contained in a backpack which an operator would wear while walking through a building along with a handheld scanner. The backpack features sensors that collect building data such as room size and shape along with associated thermal characteristics. These data can then be automatically processed to detect building elements, such as windows and lighting, and then generate 2D floor plans and 3D maps of the building geometry and thermal features. The backpack technology enables rapid data collection and export to existing computer models to guide strategies that could reduce building energy usage. Because the skills required to operate this technology are less than required for a traditional energy audit and the process is significantly faster, the overall cost of the audit can be reduced and the accuracy of the collected data is improved. This reduced cost should incentivize more building managers to conduct energy audits and implement energy saving measures.

University of California, Berkeley

Heating and Cooling the Human Body with Wirelessly Powered Devices

The University of California, Berkeley (UC Berkeley) will team with WiTricity to develop and integrate highly resonant wireless power transfer technology to deliver efficient local thermal amenities to the feet, hands, face, and trunk of occupants in workstations. Until now, local comfort devices have had little market traction because they had to be tethered by a cord to a power source. The team will leverage on-going developments in wireless charging systems for consumer electronics to integrate high-efficiency power transmitting devices with local comfort devices such as heated shoe insoles and cooled and heated office chairs. The team will develop four types of local comfort devices to deliver heating and cooling most effectively. The devices will draw very little electrical power and enable potential HVAC energy savings of at least 30%.

University of California, Los Angeles

Compact MEMS Electrocaloric Cooling Module

The University of California, Los Angeles (UCLA) is developing a novel solid state cooling technology to translate a recent scientific discovery of the so-called giant electrocaloric effect into commercially viable compact cooling systems. Traditional air conditioners use noisy, vapor compression systems that include a polluting liquid refrigerant to circulate within the air conditioner, absorb heat, and pump the heat out into the environment. Electrocaloric materials achieve the same result by heating up when placed within an electric field and cooling down when removed--effectively pumping heat out from a cooler to warmer environment. This electrocaloric-based solid state cooling system is quiet and does not use liquid refrigerants. The innovation includes developing nano-structured materials and reliable interfaces for heat exchange. With these innovations and advances in micro/nano-scale manufacturing technologies pioneered by semiconductor companies, UCLA is aiming to extend the performance/reliability of the cooling module.

University of California, Los Angeles

THermally INsulating TraNsparEnt BarrieR (THINNER) Coatings for Single-Pane Windows

The University of California, Los Angeles (UCLA) will harness advances in nanotechnology to produce thermally insulating transparent barrier (THINNER) coatings to reduce heat losses through single panes of glass. The porous coatings consist of multiple layers of silica/titania films that can simultaneously control the transmission of heat, light and thermal radiation. The internal structure of the coatings is determined by a polymer lattice that is later removed. This leaves a robust porous oxide layer that is transparent and thermally insulating. In addition to reducing heat loss, the coatings will reduce water condensation on the inner window surface and block harmful ultraviolet light. The project will also develop a scalable, high-temperature spray-on process to inexpensively deposit the coating onto glass at the factory.

University of California, San Diego

Adaptive Textiles Technology with Active Cooling & Heating (ATTACH)

The University of California, San Diego (UC San Diego) will develop smart responsive garments that enable building occupants to adjust their personal temperature settings and promote thermal comfort to reduce or eliminate the need for building-level air conditioning. The essence of building energy savings in UC San Diego's approach is based on the significant energy consumption reduction from the traditional global cooling/heating of the whole room space. This is done via localized cooling and heating only in the wearable structure in the very limited space near a person's skin. This smart textile will thermally regulate the garment's heat transport through changes in thickness and pore architecture by shrinking the textile when hot and expanding it when cold.

University of California, San Diego

"Thinner Than Air": Polymer-Based Coatings of Single-Pane Windows

The University of California, San Diego (UCSD) will develop a polymer-based thermal insulating film that can be applied onto windowpanes to reduce heat loss and condensation. The team's approach uses polymer-based coatings with specifically designed structures. Heat management is gained by the thermal conductivity of polymer and the internal thermal barriers. The coating is inherently low-emissivity, and also resists condensation and abrasion. The technology is initially designed for single-pane windows, but can be expanded in the future for use in double-pane windows, doors, and roofs, as well as potential applications in the automobile, aerospace, and military industries.

University of California, Santa Barbara

Laser-Based Solid State Lighting 

The University of California, Santa Barbara (UCSB) will develop a gallium nitride (GaN) laser-based white light emitter with no efficiency droop at high current densities. The team's solution will address the efficiency and cost limitations of LEDs. Laser diodes do not suffer efficiency droop at high current densities, and this allows for the design of lamps using a single, small, light-emitting chip operating at high current densities. Using a single chip reduces system costs compared with LEDs because the system uses less material per chip, requires fewer chips, and employs simplified optics and a simplified heat-sink. The chip area required for LED technologies will be significantly reduced using laser-based solid state lighting. This technology will also enable highly controllable beams of light that cannot be achieved with LEDs. The goal of the project is to develop a 1,000 lumen laser-based white light emitter with the efficiency of at least 200 lm/W and a cost of $0.25/klm.

University of Colorado, Boulder

Advancing Insulation Retrofits from Flexible Inexpensive Lucid Materials (AIR FILMs) for Single-Pane Windiows

The University of Colorado, Boulder (CU-Boulder) with its partners will develop a flexible window film made of nanostructured cellulose. The film can be applied onto single-pane windows to improve their energy efficiency without compromising transparency. The team will be able to economically harvest cellulose needed for the films from food waste using a bacteria-driven process. The cellulose will self-assemble into liquid crystal type structures that selectively reflect infrared light (or heat) while transmitting visible light. The technology is related to liquid crystals that are used in display screens ranging from smart phones to flat-panel HDTVs. The optical properties of these crystals arise from fine-tuning the arrangement of the individual molecules and nanostructures that compose the crystals. Engineering the liquid crystals to be transparent to visible light but able to reflect infrared light will allow heat retention in building spaces, similar to low-emissivity glass.

University of Colorado, Boulder

Radiative Cooled-Cold Storage Modules and Systems (RadiCold)

Researchers from the University of Colorado, Boulder (CU-Boulder) will develop Radicold, a radiative cooling and cold water storage system to enable supplemental cooling for thermoelectric power plants. In the Radicold system, condenser water circulates through a series of pipes and passes under a number of cooling modules before it is sent to the central water storage unit. Each cooling module consists of a novel radiative-cooling surface integrated on top of a thermosiphon, thereby simultaneously cooling the water and eliminating the need for a pump to circulate it. The microstructured polymer film discharges heat from the water by radiating in the infrared through the Earth's atmosphere into the heat sink of cold, deep space. Below the film, a metal film reflects all incoming sunlight. This results in cooling with a heat flux of more than 100 W/m2 during both day and nighttime operation. CU-Boulder will use roll-to-roll manufacturing, a low-cost manufacturing technique that is capable of high-volume production, to fabricate the microstructured RadiCold film.

University of Colorado, Boulder

Battery-Free RFID Sensor Network with spatiotemporal Pattern Network Based Data Fusion System for Human Presence Sensing

The University of Colorado, Boulder (CU-Boulder) will develop an integrated occupancy detection system based on a radio-frequency identification (RFID) sensor network combined with privacy-preserving microphones and low-resolution cameras to detect human presence. The system may also analyze electrical noise on power lines throughout a residential home to infer occupancy in different areas. The system will draw its accuracy from the combination of data sources, uncovering human presence not only from physical image and audio sensor data, but also considering what electrical activity reveals about human activity. All of these data streams (image, audio, and electrical activity) will be combined in computationally efficient ways to enable high accuracy human presence detection. The low powered devices in this system will be wirelessly powered, allowing the system to be deployed in a home without costly and invasive rewiring.

University of Florida

A New Generation Solar and Waste Heat Power Absorption Chiller

The University of Florida is improving a refrigeration system that uses low-quality heat to provide the energy needed to drive cooling. This system, known as absorption refrigeration system (ARS), typically consists of large coils that transfer heat. Unfortunately, these large heat exchanger coils are responsible for bulkiness and high cost of ARS. The University of Florida is using new materials as well as system design innovations to develop nanoengineered membranes to allow for enhanced heat exchange that reduces bulkiness. This design allows for compact, cheaper, and more reliable use of ARS that use solar or waste heat.

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