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At least 811 records · Page 45

SU-E-T-239: Design and Evaluation of a Nozzle Shielding System in Passively Scattered Proton Therapy

Purpose: To design, implement and evaluate a shielding system that will reduce out-of-field dose experienced by the patient and associated electronic systems in passively scattered proton therapy treatment. Methods: A multi-stage neutron shielding system was retrofitted to the Gantry 1 treatment nozzle at Loma Linda University Medical Center. The system uses multiple borated polyethylene plates staged after the primary beam modifying devices to attenuate and absorb neutrons produced by such devices. This arrangement locates increasing levels of shielding between the sources of secondary particles in the nozzle and the patient. Additionally, the design of this shielding structure allows it to be easily retrofitted to an existing proton nozzle system without impacting design or treatment beam characteristics. The effectiveness of the shielding was evaluated both through experimental measurements and Geant4 Monte Carlo simulations. Results: Measurements were completed with Landauer Luxel+ dosimeters that use optically stimulated luminescence and CR-39 to detect fast neutrons, thermal neutrons, protons, photons and beta particles. Measurements of a 250 MeV proton beam indicated that the shielding system reduced out-of-field dose to the patient by almost half with dose equivalent values at 50 and 40 cm from the field edge decreasing from 0.965 and 1.262 mSv/Gy to 0.596 and 0.777 mSv/Gy respectively. The installation of the multi-stage shielding system also reduced dose equivalent experienced by electronic systems installed in the treatment room by up to 80%. Geant4 simulations were also used to evaluate the neutron fluence at various positions in the treatment room as well as provide information on microdosimetry spectra within the patient and treatment room. Conclusion: The shielding system described above proved to be an effective an inexpensive method of reducing out-of-field doses to the patient and electronic systems and can be easily retrofitted to existing passive scattering nozzles.

60 APPLIED LIFE SCIENCES↗

Commercial Building Energy Saver, Web App v2.0

The CBES App is a web-based toolkit for use by small businesses and building owners and operators of small and medium size commercial buildings to perform energy benchmarking and retrofit analysis for buildings. The CBES App analyzes the energy performance of user's building for pre- and post-retrofit, in conjunction with user's input data, to identify recommended retrofit measures, energy savings and economic analysis for the selected measures.

Hong, Tianzhen↗

Weatherization Assistant NEAT/MHEA

The software provides a measure selection technique indicating cost effective retrofit activities that can be applied to a home using a standard Savings to Investment Ratio (SIR). Users must provide an input file describing the characteristics of the home to be evaluated. The software takes the input data provided and calculates energy savings and cost savings predicted for a standard set of measures given the input parameters. The Weatherization Assistant computes estimates of pre-retrofit whole building space heating and cooling energy consumptions based on the house description data supplied by the user. The consumptions are computed using a monthly heating and cooling variable base degree-day method by algorithms similar to those developed for the CIRA program [LBL, 1982]. The building consumptions are needed in computing the energy savings from measures affecting the efficiencies of the heating and cooling equipment. Weatherization Assistant then computes the energy savings and costs for each individual measure applicable to the building described as if it were the only measure installed in the house. From these energy savings, a discounted dollar savings over the life of each measure is computed. The ratio of this dollar savings to the cost of installing the measure, the "savings-to-investment ratio" (SIR), is used in an initial ranking of the measures' effectiveness. The "interacted" savings and SIR of measures are then determined assuming the measures are added to the house collectively, in order of their ranking, e.g., the second ranked measure is installed in the house initially described by the user after having been modified by the first ranked measure. If this second-ranked measure's updated SIR is greater than a user-defined limit, the measure is left implemented, else it is removed so that the next measure's effectiveness is not dependent on it. The choice between two mutually exclusive measures (such as different levels of insulation) is made on the basis of their "net present value" (NPV), the difference of life-time savings and installation cost, rather than their SIR. This has been shown to be the more correct criterion on which to base the selection between two measures, both of which cannot be installed. The audit computes and reports to the user the energy savings, discounted dollar savings, installation cost, and SIR for each measure considered cost-effective. For those with SIR greater than the user-designated cutoff, a materials list gives the material name, type, and quantity required for installation of the measure. Weatherization Assistant permits entry of pre-retrofit billing data for gas or electrically heated homes or homes with electric air-conditioning. The user may then make the decision to have the savings of the measures adjusted to reflect the difference in billed consumption and that predicted by the program.

Gettings, Michael↗

Facility Energy Decision System (FEDS) version 7.0

Designed for building energy managers, utilities and firms providing energy services, FEDS provides a comprehensive and user-friendly method for users to quickly and accurately identifying energy conversion and end-use technology improvements that offer maximum savings in energy usage and cost. FEDS enables the user to assess energy efficiency and consumption, identify retrofit opportunities, select minimum life cycle costs, determine payback, and prioritize investments in energy efficiency retrofit projects for multiple or single buildings across a particular site. As part of the life-cycle cost optimization it also considers several options for partial or complete abandonment of central energy plants including: individual technologies dropping off a thermal loop, a loop and all technologies dropping off a central plant, and all technologies and loops dropping off a central plant resulting in its complete abandonment. Improvements in release 7.0 include: FEDS 7.0 is now a full hourly simulation model (runs every hour of the year as opposed to the previous simplified hourly approach which ran 9 24-hour periods to represent each month). Enhanced building operation and occupancy modeling; New HVAC technology options (VAV, Economizers, Demand Controlled Ventilation, Terminal Reheat, Subcool Dehumidification); Additional chiller types; New lighting technologies (LED, Halogen, Induction, additional fluorescent options); Completely updated retrofit cost and performance data; Regional cost data tied to zip code (previously applied state level averages); Updated and enhanced reporting capabilities; and New pier floor model

Dirks, James↗

GHEP WIBT (Guidelines for Home Energy Professionals Weatherization Installer Badges Toolkit) [SWR-20-69]

The National Renewable Energy Laboratory (NREL) and the U.S. Department of Energy's (DOE) Weatherization Assistance Program (WAP) are collaborating with the home energy retrofit industry to support the development of skilled workers. The Installer Badges Toolkit provides a flexible, customizable, and voluntary approach to training and skills recognition for WAP implementers, utility programs, private-sector workers, and contractors. In Fiscal Year 2018, DOE, along with the Crew Leader scheme committee, determined the Retrofit Installer Technician (RIT) Job Task Analysis (JTA) could be eliminated and its tasks inserted in the Crew Leader JTA. The RIT tasks became the basis of the Installer Badges. The Badges Toolkit was updated in 2020 to add licensing and copyright agreements. Users must cite the copyright information when using or distributing copies of the Badges Toolkit in any way. The technical content has remained unchanged from previous versions of the Badges Toolkit. The Toolkit for home retrofits consists of 25 Badges, each representing different energy efficiency tasks that an installer could perform on a home. Each Badge defines the desired outcome, criteria to verify, applicable material requirements, and references to Standard Work Specifications (SWS) or other relevant standards. The Badges provide a consistent approach to training by ensuring that installers in different regions are learning the same skills nationwide. Organizations can also customize the Toolkit by choosing only those Badges that are relevant to their program. The Badges Toolkit includes five pieces: "How to Use the Badges Toolkit" provides a brief overview of how a Grantee, Subgrantee, or training provider may approach using the toolkit. The "Badges Toolkit: Worksheet" includes what to consider when determining whether and how to best incorporate the Badges into a weatherization assistance program. The "Crew Leader Job Task Analysis Spreadsheet" indicates how the Badges align with specific areas of the JTA. The "Installer Badges Passport" features separate pages for each Badge, which include places for the installer and the supervisor/trainer to record the number of times a task has been successfully completed. The "Installer Badges Verification Criteria" includes sample inspection checklists for each Badge. These can be modified as needed based on approved variance requests or more stringent requirements. They also provide a basis for consistent inspections and awarding of Badges. Note: All elements of the Badges Toolkit are designed for use by potential program implementers. They are not off-the-shelf products intended for immediate deployment. Program implementers must review and modify as needed, revise verification criteria to match local requirements, complete worksheets, and otherwise define the parameters of their own badging program.

Desai, Jal↗

Demonstration of the Hygrothermal Performance of a Next-Generation Insulation Material in a Cold Climate

Energy loss through building walls is estimated to cost the department of defense (DOD) about $200m/year, accounting for 5% of the total energy cost in DOD facilities. This article describes the demonstration of a high-performance insulation material, called modified atmosphere insulation (MAI), to reduce wall-related heat losses in a DOD building located in Ft. Drum, New York, in a cold climate. MAI has been demonstrated to achieve R32/inch (hr-ft2-°F/Btu-in) or greater and its use can significantly increase the thermal resistance of walls with a marginal increase in wall thickness, making it an ideal candidate for retrofit application. MAI is a variant of vacuum insulation panels (VIP), produced at a substantially reduced cost resulting from a change in the evacuation process.By retrofitting walls and increasing thermal resistance, as measured by R-value, by R10-20 (h-ft2-°F/Btu), reductions of 30% or more over baseline wall-generated space conditioning loads are possible. Further, with targeted applications for older or more poorly insulated facilities, greater energy savings can be achieved. In this article, the installation of MAI panels in an existing building at Ft. Drum and the resulting energy benefits will be described. Like VIPs, MAI panels consist of an evacuated nanoporous core that is encapsulated within air and vapor impermeable barrier films. Addition of these impermeable barrier films can have implications on the moisture storage and movement within the wall systems. Therefore, in addition to the thermal performance evaluation, measurements and modeling will be used to determine the hygric behavior of the retrofitted walls.

Biswas, Kaushik↗

Field Demonstration of the Brick Ontology to Scale up the Deployment of ASHRAE Guideline 36 Control Sequences

Many commercial buildings have a vast network of sensors as part of their building automation systems (BAS) that allows opportunities for energy consumption and cost savings by deploying advanced control sequences. However, this resource is often underutilized since BAS are typically programmed with simple control sequences with limited potential to deliver on these opportunities. The recent availability of ASHRAE Guideline 36 (G36) with advanced HVAC control sequences supports control retrofits in existing buildings to unlock much of the savings potential. However, barriers such as the lack of standard naming convention of building assets and data points, proprietary equipment and BAS, and the inherent uniqueness of buildings and their systems prevent building stakeholders from adopting any “plug-and-play” implementation of G36. Instead, control vendors must often undertake the manual and labor-intensive point mapping process to identify a data stream’s functional and spatial relationship within the HVAC system along with other relevant contexts and map it to the new control sequences. The vendor must carry out the point mapping process in each individual building since the mapping is unlikely to port over to another building. Even for the same building, the point mapping process can occur multiple times if various control vendors implement different control retrofits and/or multiple control retrofits happen over the lifecycle of the building. Then, there is the likelihood that G36 control sequences are programmed uniquely to the building, preventing the same implementation from being reused in another. Therefore, this paper presents a field demonstration of how we leveraged the Brick ontology with BACnet, OpenBuildingControl’s Control Description Language (CDL), and open-source support tools to implement scalable and portable advanced building controls. These tools provide standardized semantic descriptions and relationships of the building’s assets and data points (Brick), standardized communication protocol to read from and write to the building’s BAS (BACnet), and standardized code implementations (CDL) of standardized advanced control strategies (G36). We implemented G36’s hot water supply temperature setpoint reset in a Berkeley, CA building for this field demonstration. This field demonstration aims to show how integrating these tools may streamline the deployment of advanced control sequences such as G36 in a consistent manner regardless of differences found across buildings.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Highly Energy Efficient D-GLU (Directed-Green Liq-Uor Utilization) Pulping

The purpose of the project was to retrofit the front end (pulp house) of a commercial kraft pulping mill to accommodate a mill green liquor (GL) impregnation/soak/exposure and accrue downstream physical and chemical benefits while principally reducing the energy footprint of the mill. A major player in the mill contributing to excessive energy costs is the lime kiln. The project was intended to offload the energy (oil or natural gas) demands of the kiln by by-passing the causticization/slaking site in the recovery area and directly using green liquor as a pulping medium for wood. The project was run in two distinct, yet mutually compatible, phases: Phase 1 was the pre-commercial or laboratory phase in which NC State University and the Institute of Paper Science and Technology (at the Georgia Institute of Technology) ran the pulping and associated experiments, while Phase 2 was the mill scale trial. The first tri-al was run at the now defunct Evergreen Pulp Mill in Samoa, CA and lead to a partial retrofit of the mill that was not completed because it went bankrupt and the work was no longer the low-hanging fruit on the tree for the new management. The second trial was run at the MeadWestvaco Pulp Mill in Evedale, TX which for all intents and purposes was a success. They were able to fully retrofit the mill, ran the trial, studied the pulp properties, and gave us conclusions.

09 BIOMASS FUELS↗

Simulation Analyses in Support of DOE’s Fossil Fuel Rule for Single Component Equipment and Lighting Replacements

At the request of the US Department of Energy’s (DOE) Federal Energy Management Program (FEMP), Pacific Northwest National Laboratory (PNNL) conducted a series of building energy simulations using a large office model to investigate the potential savings that could be accrued from a typical chiller, boiler, or lighting replacement in a Federal office building. FEMP’s interest was in knowing whether or not single component replacements like these would have any chance of achieving the fossil- fuel-based energy consumption reduction requirements specified in Section 433 of the Energy Independence and Security Act (EISA) of 20071. Specifically, FEMP was interested in whether an older Federal building, built in the 1980s or 1990s and designed to meet energy standards in place at the time the building was designed, could meet the requirements of Section 433 of EISA for renovations. Many single component renovations like chiller replacements, boiler replacements, and lighting retrofits may meet the minimum cost requirement of Section 433 of EISA but may not offer any opportunity to achieve fossil-fuel-generated energy consumption reductions on the order of 55% or more. If single component renovations such as these would not achieve the necessary reductions, then FEMP would consider modifying rules based on Section 433 of EISA to exempt these types of single component renovations from the overall fossil-fuel-generated energy consumption reduction provisions. FEMP would instead require Federal agencies to ensure that these renovations use FEMP-designated efficiencies for chillers and boilers or the lighting power density requirements found in ASHRAE Standard 90.1-2010. The results of PNNL’s analysis indicated that it is unlikely that a combined boiler and chiller replacement, or an individual boiler or chiller replacement in an older existing Federal building would meet the requirements of Section 433 of EISA. While buildings can achieve up to 34% reduction in cooling and 11% reduction in heating load with this type of retrofit, these savings fall well short of the minimum savings specified in Section 433 of EISA. Similarly, a lighting retrofit in an older existing Federal building would also not likely meet the requirements of Section 433 of EISA. While buildings can save up to 52% on lighting loads, the whole buildings savings would be well short of the minimum savings specified in Section 433 of EISA.

Halverson, Mark A.↗

Energy Impact Illinois (Final Technical Report)

Energy Impact Illinois (EI2) is an alliance of government organizations, nonprofits, and regional utility companies led by the Chicago Metropolitan Agency for Planning (CMAP) that is dedicated to helping communities in the Chicago metropolitan area become more energy efficient. Originally organized as the Chicago Region Retrofit Ramp-Up (CR3), EI2 became part of the nationwide Better Buildings Neighborhood Program (BBNP) in May 2010 after receiving a $25 million award from the U.S. Department of Energy (DOE) authorized through the American Recovery and Reinvestment Act of 2009 (ARRA). The program’s primary goal was to fund initiatives that mitigate barriers to energy efficiency retrofitting activities across residential, multifamily, and commercial building sectors in the seven-county CMAP region and to help to build a sustainable energy efficiency marketplace. The EI2 Final Technical Report provides a detailed review of the strategies, implementation methods, challenges, lessons learned, and final results of the EI2 program during the initial grant period from 2010-2013. During the program period, EI2 successfully increased direct retrofit activity in the region and was able to make a broader impact on the energy efficiency market in the Chicago region. As the period of performance for the initial grant comes to an end, EI2’s legacy raises the bar for the region in terms of helping homeowners and building owners to take action on the continually complex issue of energy efficiency.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Balancing Hydronic Systems in Multifamily Buildings

In multifamily hydronic systems, temperature imbalance may be caused by undersized piping, improperly adjusted balancing valves, inefficient water temperature and flow levels, and owner/occupant interaction with the boilers, distribution and controls. The effects of imbalance include tenant discomfort, higher energy use intensity and inefficient building operation. This paper explores cost-effective distribution upgrades and balancing measures in multifamily hydronic systems, providing a resource to contractors, auditors, and building owners on best practices to improve tenant comfort and lower operating costs. The research was conducted by The Partnership for Advanced Residential Retrofit (PARR) in conjunction with Elevate Energy. The team surveyed existing knowledge on cost-effective retrofits for optimizing distribution in typical multifamily hydronic systems, with the aim of identifying common situations and solutions, and then conducted case studies on two Chicago area buildings with known balancing issues in order to quantify the extent of temperature imbalance. At one of these buildings a booster pump was installed on a loop to an underheated wing of the building. This study found that unit temperature in a multifamily hydronic building can vary as much as 61 degrees F, particularly if windows are opened or tenants use intermittent supplemental heating sources like oven ranges. Average temperature spread at the building as a result of this retrofit decreased from 22.1 degrees F to 15.5 degrees F.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

A New Campus Built on Efficiency - UC Merced

The University of California (UC), Merced partnered with the U.S. Department of Energy (DOE) to develop and implement solutions to retrofit two existing buildings to reduce energy consumption by at least 30% as part of DOE’s Commercial Buildings Partnerships (CBP) Program.1 Lawrence Berkeley National Laboratory (LBNL) provided technical expertise in support of this DOE program. This case study reports expected savings from proposed design recommendations for the campus, which are subject to change in final construction. It is estimated that UC Merced will achieve the 30% reduction in the two participating buildings, the central plant and the Science & Engineering (S&E) building. The savings from retrofits of those buildings represent about 17% of whole-campus energy use. In addition, the energy saved by the CBP retrofits supports a broader goal, UC Merced’s “Triple Zero” commitment to zero net energy, zero landfill waste, and zero net greenhouse gas emissions by 2020. Although the campus has already made progress toward that goal with its efficient building construction and operation, opportunities for deeper savings remain, as the CBP project demonstrates.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Balancing Hydronic Systems in Multifamily Buildings

In multifamily hydronic systems, temperature imbalance may be caused by undersized piping, improperly adjusted balancing valves, inefficient water temperature and flow levels, and owner/occupant interaction with the boilers, distribution, and controls. The imbalance leads to tenant discomfort, higher energy use intensity, and inefficient building operation. This research, conducted by Building America team Partnership for Advanced Residential Retrofit, explores cost-effective distribution upgrades and balancing measures in multifamily hydronic systems, providing a resource to contractors, auditors, and building owners on best practices to improve tenant comfort and lower operating costs. The team surveyed existing knowledge on cost-effective retrofits for optimizing distribution in typical multifamily hydronic systems, with the aim of identifying common situations and solutions, and then conducted case studies on two Chicago area buildings with known balancing issues in order to quantify the extent of temperature imbalance. At one of these buildings a booster pump was installed on a loop to an underheated wing of the building. This study found that unit temperature in a multifamily hydronic building can vary as much as 61°F, particularly if windows are opened or tenants use intermittent supplemental heating sources like oven ranges. Average temperature spread at the building as a result of this retrofit decreased from 22.1°F to 15.5°F.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

A New Campus Built on Efficiency

The University of California (UC), Merced partnered with the U.S. Department of Energy (DOE) to develop and implement solutions to reduce energy consumption by as part of DOE’s Commercial Buildings Partnerships (CBP) Program. Lawrence Berkeley National Laboratory (LBNL) provided technical expertise in support of this DOE program. This case study reports on the process and outcome of this project including the achieved savings from design improvements for the campus. The intent of the project was to retrofit the Science & Engineering (S&E) building and the central plant at UC Merced to achieve up to 30% energy reduction. The anticipated savings from these retrofits represented about 17% of whole-campus energy use. If achieved, the savings contribution from the CBP project would have brought overall campus performance to 56% of the 1999 UC/CSU benchmark performance for their portfolio of buildings. However, the final design that moved forward as part of the CBP program only included the retrofit measures for the S&E building.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

SMART Scale An Innovative Program Accelerating the Energy Efficiency Market

Small business is a major component of the American economy. More than half of all private sector workers in this country are employed by small businesses and nearly two-thirds of the new jobs generated in the last ten years were created in this sector. Studies have shown that buildings of less than 50,000 square feet represent 94% of the commercial sector and half of all non-residential floor space in the United States. The future of the American economy relies on a vibrant, robust, and profitable small business community. Small and mid-sized businesses (SMB) can increase their profitability by reducing their operating costs through energy efficiency. The SMART Scale program delivers deep retrofits that maximize energy and cost savings for the SMB market and can be adapted throughout the country in markets of all sizes. For the past 14 years, Ecology Action has been perfecting a Direct Install (DI) program for the SMB market that offers this sector the type of sophisticated, comprehensive energy saving opportunities that were previously available only to large commercial and industrial customers. The DI 2.0 model that Ecology Action has administered for several public and investor-owned California utilities, and most recently for the Sacramento Municipal Utilities District (SMUD), provides the template for a successful retrofit program that can address the unique barriers faced by the SMB sector and achieve a greater impact than traditional DI programs. The impressive results produced by the DI 2.0 program prompted the US Department of Energy to award Ecology Action a $2 million grant in 2013 to create, demonstrate and roll out a replicable model for delivering deep retrofits to small commercial buildings. The grant enabled Ecology Action to build on the success of DI 2.0 by incorporating improvements into the model, market-testing it and designing a costeffective method of achieving significant energy savings for small businesses across the country.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

High-Efficiency Housing at the Fort Peck Indian Reservation: Opportunities and Lessons Learned

This project was initiated to provide design assistance in an effort to maximize energy performance for affordable housing at the Fort Peck Indian Reservation near Poplar, Montana. The Make It Right Foundation (MIRF) built 20 high performing homes (LEED Platinum) in 2015 and 2016 with three (3) different design options. NREL and EPA set out to provide energy analysis along with measurement and verification (M and V) of the homes to characterize energy use and provide clarity for future decision making with regard to tribal housing options. The results included herein summarize the energy end uses and documents projected energy impacts from various aspects of the MIRF home designs and construction. This report includes an analysis of energy use in 5 MIRF homes, comparing energy use across the different styles and configurations. Energy models were created for the 2 styles of MIRF homes, including renewable energy assessment for photovoltaic (PV) systems. Existing tribal housing has also been analyzed, with 5 housing units being analyzed for energy use and an energy model being created for 1 housing unit. The findings of this study highlight many of the challenges that arise when attempting to construct high performance housing in a region where such construction practices are still relatively rare. Homes in Poplar are well designed and, for the most part, and include climate specific design considerations appropriate for northeastern Montana. The most significant issues identified in MIRF homes were related to the work done to put the homes on the foundation, insulate the crawlspaces, and do final connection with the utilities. The Taxed II Credit homes are well designed and well suited to northeastern Montana, and with slight modifications to the design and construction could be very efficient. All occupant comfort and energy usage issues that were identified during the site visits can be remedied through retrofit measures that are relatively inexpensive. Energy efficiency opportunities were found that can be implemented in each of the homes. These retrofits are generally inexpensive and have a quick return on investment. While the MIRF houses as well as the Taxed II Credit homes can achieve high levels of energy performance with modest retrofits. Similar houses built in the future could achieve even better performance with minor design changes, and generally low incremental cost. Renewable energy systems are economically feasible in this area, but the payback is on the high side of what would likely be acceptable to homeowners. If the price of solar comes down to $2/watt installed, the systems will achieve a simple payback of 13 years, which is likely a return on investment that is attractive to homeowners. If the homes are made sufficiently tight to be high performance, energy recovery ventilators will be necessary to maintain acceptable indoor air quality. The Taxed II Credit homes are already equipped with heat recovery ventilators (HRVs), and they seem to function well. As PV prices continue to decline, start implementing projects as they become cost effective.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Advanced Ultrasupercritical (AUSC) Materials Thick-Walled Cycling Header Development for ComTest-AUSC (Final Report)

Alstom Power Inc., a wholly owned subsidiary of the General Electric Company (GE) recently completed “Advanced Ultrasupercritical (AUSC) Materials Thick-Walled Cycling Header Development for ComTest-AUSC” under Award No. DE-FE0026183 for the U.S. Department of Energy National Energy Technology Laboratory (DOE NETL). This project developed a design for testing of a high temperature nickel-based superalloy thick-walled header to simulate cycling and flexible plant operation in new and existing plants. The objective was to simulate the expected thermal stresses of a new AUSC plant or a retrofit header in an existing plant to improve flexible dynamic operation while maintaining component integrity and overall power plant reliability. The high performance superalloy materials that enable higher operating temperatures and pressures can support future transformational power technologies including new AUSC plants at 4250-5000 psi, 730°C/760°C or will serve as a replacement component in a repowered or retrofit USC coal powered cycling plant at 3600 psi, 600°C. These alloys can also enable supercritical CO2 cycles, nuclear power, solar power and more efficient natural gas combined cycle units as targeted by the U.S. DOE/NETL Cross-Cutting Research Technology Program Plan. Recently developed advanced nickel alloys such as Inconel 740H (740H) and Haynes 282 (H282) have been successfully tested on a pilot scale for fireside corrosion using steam loop tubing at AUSC temperatures of 760°C in actual operating coal fired boiler. These high strength materials have been demonstrated their adequacy for use in other high temperature boiler components such as superheater tubes. Thick-walled superheater outlet headers which operate at high temperatures and pressure under severe cycling condition are considered as one of the most critical component in the AUSC coal fired boiler. Over the design life of a plant, these headers are exposed to the most severe fatigue and creep damage accumulation and need to be properly designed for the expected cycling in an AUSC plant with flexible operation. These materials need to demonstrate adequate design life of 20 to 30 years for creep and fatigue conditions. The following tasks were performed: 1. A conceptual design was developed of a thick-walled component representative of typical headers with several tube connections and proper flow rates (~100,000 lbs/hr) suitable for Phase II test at 760°C operation. This was based on a process analysis of expected full scale new and component retrofit designs for AUSC; 2. A multi-physics flow and heat transfer computational fluid dynamics (CFD) analysis of the component for proper layout of the header configuration, number and geometry (size) of tubes required for bypass flow, flow rates through the tubing, and sectional pressure drops was performed. Steam to header metal heat transfer film coefficients in the header section and the tubes during the two stages (half load and full load) of the cycling operation were evaluated and used in the stress analysis; 3. Detailed analytical evaluation of the thick-walled pipe and tube connections for mechanical integrity under cycling conditions was performed. This included transient thermal stress analysis and fatigue usage estimation including the tube-to-pipe weld geometries and weld materials; 4. A layout and design of the thick-walled test component was developed and instrumentation required for a test was identified; 5. Continuum Damage Mechanics (CDM) creep prediction models were extended to 740H and H282 and validated with public data on 740H and H282 for use in creep analysis. In addition, detailed creep analyses were performed separately for the design life of the conceptual AUSC superheater outlet header using these General Electric (GE) creep constitutive models. GE was the prime contractor for the project, which was directed by Principal Investigator Robert Schrecengost and Lead Scientist Dr. B. Reddy Ganta. Other collaborative participants in this project included GE Global Research, GE Boiler Engineering, and a Technical Consultant from EPRI.

01 COAL, LIGNITE, AND PEAT↗

Transforming LA’s Urban Landscape - SoCal Edge Final Report

Existing commercial and retail buildings represent roughly 40% of the total electricity sales by utilities across the United States. Current programmatic efforts focus on individual technologies and struggle with comprehensive impactful energy retrofits due to cost-effectiveness concerns, customization requiring specialized contractors, and disruption of building operation. The SoCal Edge program, operated by the Los Angeles Cleantech (LACI) Incubator and the LA Better Buildings Challenge (LABBC), promoted an innovative and integrated approach to achieving deep energy savings by leveraging portfolio properties and developing packages of technologies that can be specified into building retrofits and integrated into combined solutions that can transform the retrofit market in a truly meaningful way.

99 GENERAL AND MISCELLANEOUS↗