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At least 1,315 records · Page 73

Final Technical Report - Polymeric Multilayer Infrared Reflecting Mirrors

The goal of this project was to develop a clear, polymeric, multilayer film with an expanded infrared (IR) reflection band which would allow improved rejection of incident IR energy. The IR reflection band is covering the region from about 850 nm to 1830 nm. This film is essentially clear and colorless in the visible portion of the electromagnetic spectra (visible light transmission of about 89%) while reflecting 90-95% of the IR energy over the portion of the spectra indicated above. This film has a nominal thickness of 3 mils, is polymeric in nature (contains no metals, metal oxides, or other material types) and is essentially clear in appearance This film can then be used as a component of other products such as a solar window film, an IR reflecting interlayer for laminated glass, a heat rejecting skylight film, a base film for daylight redirecting products, a greenhouse film, and many more applications. One of the main strengths of this product is that because it is a standalone IR rejecting film, it can be incorporated and retrofitted into many applications that desire or require the transmission of visible light, but want to block other portions of the solar spectra, especially the IR portion. Many of the applications exist in the window glazing product area where this film can provide for substantial energy improvements in applications where visible light is desired.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Construction Guidelines for High R-Value Walls without Exterior Rigid Insulation

High R-value wall assemblies (R-40 and above) are gaining popularity in the market due to programs such as the U.S. Department of Energy Zero Energy Ready Home program, Passive House, Net Zero Energy Home challenges in several states, and highly incentivized retrofit programs. In response to this demand, several builders have successfully used double-wall systems to achieve higher R-values in thicker, framed walls. To builders of conventional stick-framed homes, often one of the most appealing features of double-wall systems is that there are very few new exterior details. Exterior sheathings, structural bracings, house wraps or building paper, window and door flashings, and siding attachments are usually identical to good details in conventional framed-wall systems. However, although the details in double-wall systems are very similar to those in conventional stick framing, there is sometimes less room for error. Several studies have confirmed colder temperatures of exterior sheathing in high R-value wall assemblies that do not have exterior rigid foam insulation. These colder temperatures can lead to increased chances for condensation from air exfiltration, and they have the potential to result in moisture-related problems (Straube and Smegal 2009, Arena 2014, Ueno 2015). The information presented in this guide is intended to reduce the risk of failure in these types of assemblies, increase durability, and reduce material brought to landfills due to failures and resulting decay. Although this document focuses on double-wall framing techniques, the majority of the information about how to properly construct and finish high R-value assemblies is applicable to all wall assemblies that do not have foam insulation installed on the exterior of the structural sheathing. The techniques presented have been shown through field studies to reduce the likelihood of mold growth and moisture-related damage and are intended for builders, framing contractors, architects, and consultants involved in designing and building super-insulated homes. The information is applicable to both new construction and gut-rehabilitation projects in Climate Zones 5 and higher.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

NRG CO 2 NCEPT - Confirmation Of Novel Cost-effective Emerging Post-combustion Technology

Under DOE's solicitation DE-FOA-0001190, NRG and Inventys conceptualized a Large-Scale pilot (>10MWe) post-combustion CO 2 capture project using Inventys' VeloxoThermTM carbon capture technology. The technology is comprised of an intensified thermal swing adsorption (TSA) process that uses a patented architecture of structured adsorbent and a novel process design and embodiment to capture CO 2 from industrial flue gas streams. The result of this work concluded that the retrofit of this technology is economically and technically viable, but that the sorbent material selected for the program would need improving to meet the techno-economic performance requirements of the solicitation.

20 FOSSIL-FUELED POWER PLANTS↗

Durable Airtightness in Single-Family Dwellings: Field Measurements

Durability of building envelope is important to new homes that are increasingly built with improved levels of airtightness. It is also important to weatherized homes such that energy savings from retrofit measures, such as air sealing, are persistent. We presented a comparison of air leakage measurements collected in November 2013 through March 2014, with two sets of prior data collected between 2001-2003 from 17 new homes located near Atlanta, GA, and 17 homes near Boise, ID that were weatherized in 2007-2008. The purpose of the comparison is to determine if there are changes to the airtightness of building envelopes over time. The air leakage increased in all but one of the new homes, with a mean increase of about 25%. The weatherized homes also showed an increase in the mean air leakage (12%). We performed a regression analysis to describe the relationship between prior and current measurements in terms of normalized leakage (NL). The best estimate of the aging factor predicts a 15% increase in NL over ten years. Further analysis using ResDB data (LBNL’s Residential Diagnostic Database) showed the expected changes in air leakage if aging were modeled. These results imply that we should examine the causes of increased leakage and methods to avoid them. This increase in leakage with time should be accounted for in long-term population-wide energy savings estimates, such as those used in ratings or energy savings programs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Laboratory Evaluation of Energy Recovery Ventilators

Over the years, building scientists have characterized the relationship between building airtightness, exhaust-only appliances airflows, and building depressurization. Now, as the use of deep retrofit measures and new construction practices is growing to realize lower infiltration levels in increasingly tighter envelopes, performance issues can arise with the operation of exhaust-only appliances in a depressurized home. As the depressurization levels climb in tighter homes, many of these exhaust-only appliances see their rated airflows reduced and other related performance issues arise as a result. If sufficiently depressurized, atmospherically vented combustion appliances that may be present in the home can backdraft as well. Furthermore, when exhaust-only appliances operate and the tight home becomes depressurized, water vapor intrusion from outdoors can raise additional issues of mold in the building envelope in more humid climates.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Heart of the Hearth: Making the Popular Clean, Not the Clean Popular - Technology Research, Development, and Tools for Clean Biomass Cookstoves

This technical report summarizes the work completed by BioLite in fulfilment of the US DOE EERE award. The work plan focused on three key objectives: developing an optimized combustion system that demonstrates high combustion efficiency and low PM 2.5 and CO emissions, integrate the system into popular stove phenotypes – side-fed rocket stove architecture like the BioLite HomeStove, and the Patsari chimney stove in Mexico such that they maintain their important phenotypical characteristics, independently evaluate quantitative fuel and emissions performance of the integrated ‘Turbo-Patsari’ in Mexican households. The project activities were organized into six major tasks: A. Develop, fabricate, and test proof-of-concept prototypes B. Develop field prototypes, assess user feedback and field performance C. Define revised stove design for pre-production model, Identify manufacturing requirements and estimated cost to build, Conduct reliability, emissions, and performance testing of pre-production Turbo-Patsari D. Build pre-production Turbo-Patsari stove combustion cores E. Conduct pre-production field trials F. Summarize field trial results and evaluate Turbo-Patsari for potential volume production. A two-pronged approach was adopted for the above tasks. The first involved building a modular test platform that allowed parametric variation of multiple stove design parameters that directly affect its performance – heat output, thermal efficiency, and emissions. The second part of the approach comprised of building a surrogate Patsari based on GIRA’s specifications that could then be modified or retrofitted for optimum performance based on the learnings from the modular test platform. The following sections of the report will describe the findings of tests on these platform, the subsequent development, design, and installation of the Turbo-Patsari, and finally the in-home field trial.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

America Saves! Energizing Main Street's Small Businesses

The America Saves! Energizing Main Street Small Businesses project engaged the 1,200-member National Main Street Center (NMSC) network of downtown organizations and other local, regional, and national partners to test a methodology for sharing customized energy efficiency information with owners of commercial buildings smaller than 50,000 square feet. Led by the National Trust for Historic Preservation’s Preservation Green Lab, the project marshalled local staff and volunteers to gather voluntarily-disclosed energy use information from participating businesses. This information was analyzed using a remote auditing tool (validated by the National Renewable Energy Lab) to assess energy savings opportunities and design retrofit strategies targeting seven building types (food service and sales, attached mixed-use, strip mall, retail, office, lodging, and schools). The original project design contemplated extensive leveraging of the Green Button protocol for sharing annualized utility data at a district scale. Due the lack of adoption of Green Button, the project partners developed customized approaches to data collection in each of twelve pilot communities. The project team encountered considerable challenges in gathering standardized annual utility data from local partners. After overcoming these issues, the data was uploaded to a data storehouse. Over 450 properties were benchmarked and the remote auditing tool was tested using full building profiles and utility records for more than 100 commercial properties in three of the pilot communities. The audit tool demonstrated potential for quickly capturing, analyzing, and communicating energy efficiency opportunities in small commercial buildings. However, the project team found that the unique physical characteristics and use patterns (partial vacancy, periodic intensive uses) of small commercial buildings required more trouble-shooting and data correction than was anticipated. In addition, the project revealed that remote technology alone (such as audits) is not sufficient to convince most owners of commercial buildings or businesses to invest in energy efficiency. Additional, one-on-one personal communication is critical. A combination of technology and well-planned direct contact is likely to produce the highest rate of energy efficiency implementation in the small commercial building market sector. Note that only two of the three planned phases of this project were completed. As a result, research and testing were not fully implemented and thus all results and conclusions from the America Saves! Energizing Main Street Small Businesses project should be considered preliminary. In addition to the National Main Street Center, local organizations, and regional utilities, the America Saves! project partners included the National Renewable Energy Laboratory, Energy Center of Wisconsin (Seventh Wave), Lend Lease, Building Energy, and Energy RM.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

FY16 Safeguards Technology Cart-Portable Mass Spectrometer Project Final Report

The Oak Ridge National Laboratory project for the Next Generation Safeguards Initiative Safeguards Technology Development Subprogram has been involved in the development of a cart portable mass spectrometer based on a Thermo ITQ ion trap mass spectrometer (referred to simply as the ITQ) for the field analysis of 235U/238U ratios in UF6. A recent discovery of the project was that combining CO2 with UF6 and introducing the mixture to the mass spectrometer (MS) appeared to increase the ionization efficiency and, thus, reduce the amount of UF6 needed for an analysis while also reducing the corrosive effects of the sample. However, initial experimentation indicated that mixing parameters should be closely controlled to ensure reproducible results. To this end, a sample manifold (SM) that would ensure the precise mixing of UF6 and CO2 was designed and constructed. A number of experiments were outlined and conducted to determine optimum MS and SM conditions which would provide the most stable isotope ratio analysis. The principal objective of the project was to provide a retrofit ITQ mass spectrometer operating with a SM capable of achieving a variation in precision of less than 1% over 1 hour of sampling. This goal was achieved by project end with a variation in precision of 0.5 to 0.8% over 1 hour of sampling.

47 OTHER INSTRUMENTATION↗

Measured Performance of a Varied Airflow Small-Diameter Duct System

This study tests the performance of a variable airflow small-diameter duct heating, ventilation, and air conditioning (HVAC) system in a new construction unoccupied low-load test house in Pittsburgh, Pennsylvania. The duct system was installed entirely in conditioned space and was operated from the winter through summer seasons. Measurements were collected on the in-room temperatures and energy consumed by the air handler and heat pump unit. Operation modes with three different volumes of airflow were compared to determine the ideal airflow scenario that maximizes room-to-room thermal uniformity while minimizing fan energy consumption. Black felt infrared imagery was used as a measure of diffuser throw and in-room air mixing. Measured results indicate the small-diameter, high velocity airflow system can provide comfort under some conditions. Solar heat gains resulted in southern rooms drifting beyond acceptable temperature limits. Insufficient airflow to some bedrooms also resulted in periods of potential discomfort. Homebuilders or HVAC contractors can use these results to assess whether this space conditioning strategy is an attractive alternative to a traditional duct system. The team performed a cost analysis of two duct system configurations: (1) a conventional diameter and velocity duct system, and (2) the small-diameter duct system. This work applies to both new and retrofit homes that have achieved a low heating and cooling density either by energy conservation or by operation in a mild climate with few heating or cooling degree days. Guidance is provided on cost trade-offs between the conventional duct system and the small-diameter duct system.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

3D-printed, integrated plug-and-play turbine-generator set for very-low-head hydro. Final Technical Report DOE-EMotors-15757-1

Hydro power has been used since the early days of electricity, but is generally limited to very large facilities. There remains a vast array of untapped locations, either rivers, tidal currents, or also man-made facilities where energy harvesting is technically feasible, but still too costly. E-Motors, in partnership with MTI, is developing an integrated design aimed at facilitating manufacturing, installation, and retrofitting. The integrated design includes a rim on the outside of the turbine runner to house the electrical generator rotor, a so-called rim drive. With this approach, a compact, in-line assembly can be produced and placed in straight pipes, without having to resort to elbows, shafts, and outside generators, thus improving efficiency and facilitating assembly. The long term goal of the project is to develop a realistic prototype for market development and start of manufacturing. During this Phase I grant, in collaboration with the University of Wisconsin-Milwaukee (UWM), the team pursued two objectives: First, design and test a small (3”) system in a laboratory at UWM, and second develop a prototype design at higher power between 50 and 100 kW. The tests showed the potential for integrating the generator rotor with the turbine runner. Output power is so far limited due to test conditions, but CFD calculations show good efficiency potential. With the larger system, a number of possibilities were explored, including: a generator design matching the turbine output, and capable of generating a peak of 86 kW from a flow of 136 cfs at 9’ of head; various intake tube geometries, showing that an elliptical shape is quite favorable; removing the hub, something made possible with a rim design, which can improve efficiency by about 10 percentage points.

13 HYDRO ENERGY↗

Prototype Development and Evaluation of Self-Cleaning Concentrated Solar Power Collectors

The feasibility of integrating and retrofitting transparent electrodynamic screens (EDS) on the front surfaces of solar collectors was established as a means to provide active self-cleaning properties for parabolic trough and heliostat reflectors, solar panels, and Fresnel lenses. Prototype EDS-integrated solar collectors, including second-surface glass mirrors, metallized Acrylic-film mirrors, and dielectric mirrors, were produced and tested in environmental test chambers for removing the dust layer deposited on the front surface of the mirrors. The evaluation of the prototype EDS-integrated mirrors was conducted using dust and environmental conditions that simulate the field conditions of the Mojave Desert. Test results showed that the specular reflectivity of the mirrors could be maintained at over 90% over a wide range of dust loadings ranging from 0 to 10 g/m 2 , with particle diameter varying from 1 to 50 μm. The measurement of specular reflectivity (SR) was performed using a D&S Reflectometer at wavelength 660 nm. A non-contact reflectometer was designed and constructed for rapid measurement of specular reflectivity at the same wavelength. The use of this new noncontact instrument allowed us to measure SR before and after EDS activation. Several EDS prototypes were constructed and evaluated with different electrode configurations, electrode materials, and encapsulating dielectric materials.

14 SOLAR ENERGY↗

Model-Based Sensor Placement for Component Condition Monitoring and Fault Diagnosis in Fossil Energy Systems

Design and operation of energy producing, near “zero-emission” coal plants has become a national imperative. This report on model-based sensor placement describes a transformative two-tier approach to identify the optimum placement, number, and type of sensors for condition monitoring and fault diagnosis in fossil energy system operations. The algorithms are tested on a high fidelity model of the integrated gasification combined cycle (IGCC) plant. For a condition monitoring network, whether equipment should be considered at a unit level or a systems level depends upon the criticality of the process equipment, its likeliness to fail, and the level of resolution desired for any specific failure. Because of the presence of a high fidelity model at the unit level, a sensor network can be designed to monitor the spatial profile of the states and estimate fault severity levels. In an IGCC plant, besides the gasifier, the sour water gas shift (WGS) reactor plays an important role. In view of this, condition monitoring of the sour WGS reactor is considered at the unit level, while a detailed plant-wide model of gasification island, including sour WGS reactor and the Selexol process, is considered for fault diagnosis at the system-level. Finally, the developed algorithms unify the two levels and identifies an optimal sensor network that maximizes the effectiveness of the overall system-level fault diagnosis and component-level condition monitoring. This work could have a major impact on the design and operation of future fossil energy plants, particularly at the grassroots level where the sensor network is yet to be identified. In addition, the same algorithms developed in this report can be further enhanced to be used in retrofits, where the objectives could be upgrade (addition of more sensors) and relocation of existing sensors.

20 FOSSIL-FUELED POWER PLANTS↗

Fort Mason Center: Pier 2 Project

The rooftop Photovoltaic (PV) panels and radiant piping project was constructed by Fort Mason Center as part of its $21 million comprehensive rehabilitation of the Pier 2 shed which include the shed’s electrical, natural gas and water systems. Fort Mason Center improved performance while reducing energy and water usage and costs to demonstrate the efficiencies and opportunities available to large multi-function facilities. The scalable demand of these facilities required a layered approach to conservation, control and production. The project employed a comprehensive retrofit of electrical natural gas, and plumbing systems to maximize efficiency and lower carbon footprint specifically to demonstrate the effectiveness of these strategies in a public setting with varied and diverse use. The project was completed in July 2014 and met the expected outcomes regarding increased comfort and operational efficiency throughout the Pier 2 shed as well as on site electrical generation of current consumption. The entire Pier 2 shed project won a 2015 California Preservation Foundation design award for historic rehabilitation.

14 SOLAR ENERGY↗

Combined Pressure, Temperature Contrast and Surface-Enhanced Separation of Carbon Dioxide for Post-Combustion Carbon Capture

The Rice University research team developed a hybrid carbon dioxide (CO 2 ) absorption process combining absorber and stripper columns using a high surface area ceramic foam gas-liquid contactor for enhanced mass transfer and utilizing waste heat for regeneration. This integrated absorber/desorber arrangement will reduce space requirements, an important factor for retrofitting existing coal-fired power plants with CO 2 capture technology. Described in this report, we performed an initial analysis to estimate the technical and economic feasibility of the process. A one-dimensional (1D) CO 2 absorption column was fabricated to measure the hydrodynamic and mass transfer characteristics of the ceramic foam. A bench-scale prototype was constructed to implement the complete CO 2 separation process and tested to study various aspects of fluid flow in the process. A model was developed to simulate the two-dimensional (2D) fluid flow and optimize the CO 2 capture process. Test results were used to develop a final technoeconomic analysis and identify the most appropriate absorbent as well as optimum operating conditions to minimize capital and operating costs. Finally, a technoeconomic study was performed to assess the feasibility of integrating the process into a 600 megawatt electric (MWe) coal-fired power plant. With process optimization, $82/MWh of COE can be achieved using our integrated absorber/desorber CO 2 capture technology, which is very close to DOE's target that no more than a 35% increase in COE with CCS. An environmental, health, and safety (EH&S) assessment of the capture process indicated no significant concern in terms of EH&S effects or legislative compliance.

54 ENVIRONMENTAL SCIENCES↗

Laboratory Evaluation of Energy Recovery Ventilators

Over the years, building scientists have characterized the relationship between building airtightness, exhaust-only appliances airflows, and building depressurization. Now, as the use of deep retrofit measures and new construction practices is growing to realize lower infiltration levels in increasingly tighter envelopes, performance issues can arise with the operation of exhaust-only appliances in a depressurized home. As the depressurization levels climb in tighter homes, many of these exhaust-only appliances see their rated airflows reduced and other related performance issues arise as a result. If sufficiently depressurized, atmospherically vented combustion appliances that may be present in the home can backdraft as well. Furthermore, when exhaust-only appliances operate and the tight home becomes depressurized, water vapor intrusion from outdoors can raise additional issues of mold in the building envelope in more humid climates.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Measured Performance of a Varied Airflow Small-Diameter Duct System

This study tests the performance of a variable airflow small-diameter duct heating, ventilation, and air conditioning (HVAC) system in a new construction unoccupied low-load test house in Pittsburgh, Pennsylvania. The duct system was installed entirely in conditioned space and was operated from the winter through summer seasons. Measurements were collected on the in-room temperatures and energy consumed by the air handler and heat pump unit. Operation modes with three different volumes of airflow were compared to determine the ideal airflow scenario that maximizes room-to-room thermal uniformity while minimizing fan energy consumption. Black felt infrared imagery was used as a measure of diffuser throw and in-room air mixing. Measured results indicate the small-diameter, high velocity airflow system can provide comfort under some conditions. Solar heat gains resulted in southern rooms drifting beyond acceptable temperature limits. Insufficient airflow to some bedrooms also resulted in periods of potential discomfort. Homebuilders or HVAC contractors can use these results to assess whether this space conditioning strategy is an attractive alternative to a traditional duct system. The team performed a cost analysis of two duct system configurations: (1) a conventional diameter and velocity duct system, and (2) the small-diameter duct system. This work applies to both new and retrofit homes that have achieved a low heating and cooling density either by energy conservation or by operation in a mild climate with few heating or cooling degree days. Guidance is provided on cost trade-offs between the conventional duct system and the small-diameter duct system.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Gauging the Impact of Various Definitions of Low- and Moderate-Income Communities on Possible Electricity Savings From Weatherization

With rising interest in lowering energy costs for low- and moderate-income households, the U.S. Department of Energy (DOE) asked Lawrence Berkeley National Laboratory (LBNL) to assess the implications of pursuing energy efficiency neighborhood-by-neighborhood where those households are most prevalent. DOE provided certain scenarios for qualifying geographic areas as “low- and moderate-income communities,” and LBNL used data on demographics, housing types and recent savings from low-income retrofits or weatherization to provide rough electricity savings estimates under those scenarios.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Crowdsourced Microfinance for Energy Efficiency in Underserved Communities

BlocPower’s mission is to provide access to energy efficiency financing for underserved communities across the United States. This project, “Crowdsourced Microfinance for Energy Efficiency in Underserved Communities,” is an extension of that goal and is grounded in the principles of providing engineering and financing services to those in need. The project is based on the creation of a BlocPower Marketplace as a central hub for connecting shovel-ready green buildings to institutional investors. This ‘connection’ entails using online crowdfunding to aggregate debt and equity capital from institutional investors to connect to customers (building owners) across various financial portfolios. BlocPower Marketplace is intended to bring social, environmental, and financial returns to investors while also decreasing investor risk by loaning out funds for energy installations in individual buildings. In detail, the intended benefits of crowdsourcing are two-sided. Firstly, for building owners, clean energy retrofit installations improve building operations, reduce utility costs, and reduce harmful impacts to their surrounding environment. Secondly, for institutional investors, they gain access to a new market of energy efficiency and are able to provide debt or equity capital with high financial returns. This gives investors the opportunity to create social and environmental impact in communities around the country as well. With this in mind, BlocPower designed the marketplace to specifically answer exploratory research questions with respect to the pricing of energy financing. Institutional investors typically charge high rates on project financing solutions in the energy space, particularly in low and middle-income communities, because of fears that required debt service will not be made. This makes access to energy capital exorbitantly difficult for those that need it the most. Through this project, BlocPower tested investor appetite to determine if crowdsourcing would lower prices and subsequently lower barriers to entry for underserved communities’ access to energy capital. BlocPower’s results in this project were extremely informative for the industry. The project demonstrates that the marketplace is a scalable tool to help overcome barriers to entry for small building owners in underserved communities to access energy efficiency financing, but that crowdfunding by itself does not necessarily lower interest rates and make energy efficiency projects feasible. For that, we need a repayment mechanism that lowers perceived risk. That mechanism is on bill repayment.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗