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This slide deck provides an overview of community solar program design and subscription models. It introduces and explains the different elements of community solar program and subscription design, and proves proven practices and considerations when designing a community solar program. This slide deck was developed for a continuing education course hosted by the American Public Power Association (APPA).
The analytical techniques and computer program developed in the fully-coupled rotor vibration study are described. The rotor blade natural frequency and mode shape analysis was implemented in a digital computer program designated DF1758. The program computes collective, cyclic, and scissor modes for a single blade within a specified range of frequency for specified values of rotor RPM and collective angle. The analysis includes effects of blade twist, cg offset from reference axis, and shear center offset from reference axis. Coupled inplane, out-of-plane, and torsional vibrations are considered. Normalized displacements, shear forces and moments may be printed out and Calcomp plots of natural frequencies as a function of rotor RPM may be produced.
Managing a research and development (R&D) portfolio presents numerous challenges, such as prioritizing research areas, remaining agile, strategic workforce planning, and measuring return on investment, impact, and innovation. One government R&D program is charged with producing a high degree of innovative, transformational breakthroughs in aviation technology. A practical, structured methodology for strategically prioritizing emerging aviation R&D in such an environment is lacking. The existing multi-criteria decision aid tools are primarily utilized at an enterprise level, take months to set up and collect data, require large teams of experts, are used on an infrequent basis, and are not conducive to a highly innovative, high-risk portfolio. Prior to audaciously creating a new portfolio prioritization process, the exact challenges with portfolio management for R&D projects were identified using the design thinking and lean start-up methods. A key part of this discovery process was interviewing stakeholders, as well as other managers of organizations charged with producing innovative portfolios. These interviews, as well as additional techniques, were used to develop a deeper understanding of the challenges and, subsequently, lay the foundation for development of an effective portfolio prioritization process. Four potential concepts that represent key findings emerged: carefully selected criteria for portfolio assessment and selection, targeted portfolio turnover rate, dynamic portfolio prioritization framework, and streamlined transition or commercialization of R&D. Acting on any one of the resulting portfolio management concepts will increase the transparency and confidence in portfolio decisions and, ideally, result in a greater degree of transformational breakthroughs in aviation technology.
Program relieves designer of most of the computational details, while he maintains control over most engineering decisions. Number of specifications that must be supplied by user allows for considerable flexibility and for exercise of engineering judgment. Speed of program makes it possible to run many cases, economically determining effect of various parameter changes.
The expanded capabilities for analysis and design of low speed flap systems afforded by recent modifications of an existing computer program is described. The program provides for the simultaneous analysis of up to 25 pairs of leading-edge and trailing-edge flap deflection schedules. Among other new features of the program are a revised attainable thrust estimation method to provide more accurate predictions for low Mach numbers, and a choice of three options for estimation of leading-edge separation vortex flow effects. Comparison of program results with low speed experimental data for an arrow wing supersonic cruise configuration with leading-edge and trailing-edge flaps showed good agreement over most of the range of flap deflections. Other force data comparisons and an independent study of airfoil and wing pressure distributions indicated that wind-tunnel measurements of the aerodynamic performance of twisted and cambered wings and wings with leading-edge flaps can be very sensitive to Reynolds number effects.
In the fall of 2010, the Alabama Department of Economic and Community Affairs (ADECA) launched the Multi-State Model for Catalyzing the National Home Energy Retrofit Market Project (Multi-State Project). This residential energy efficiency pilot program was a collaborative effort among the states of Alabama, Massachusetts, Virginia, and Washington, and was funded by competitive State Energy Program (SEP) awards through the U.S. Department of Energy (DOE). The objective of this project was to catalyze the home energy efficiency retrofit market in select areas within the state of Alabama. To achieve this goal, the project addressed a variety of marketplace elements that did not exist, or were underdeveloped, at the outset of the effort. These included establishing minimum standards and credentials for marketplace suppliers, educating and engaging homeowners on the benefits of energy efficiency and addressing real or perceived financial barriers to investments in whole-home energy efficiency, among others. The anticipated effect of the activities would be increased market demand for retrofits, improved audit to retrofit conversion rates and growth in overall community understanding of energy efficiency. The four-state collaborative was created with the intent of accelerating market transformation by allowing each state to learn from their peers, each of whom possessed different starting points, resources, and strategies for achieving the overall objective. The four partner states engaged the National Association of State Energy Officials (NASEO) to oversee a project steering committee and to manage the project evaluation for all four states. The steering committee, comprised of key program partners, met on a regular basis to provide overall project coordination, guidance, and progress assessment. While there were variances in program design among the states, there were several common elements: use of the Energy Performance Score (EPS) platform; an audit and home energy rating tool; emphasis on community based coordination and partnerships; marketing and outreach to increase homeowner participation; training for market actors; access to financing options including rebates, incentives, and loan products; and an in depth process evaluation to support continual program improvement and analysis. In Alabama, Nexus Energy Center operated energy efficiency retrofit programs in Huntsville and Birmingham. In the Huntsville community the AlabamaWISE program was available in five Alabama counties: Cullman, Lawrence, Limestone, Madison, and Morgan. In Birmingham, the program was available to residents in Jefferson and Shelby Counties. In both communities, the program was similar in terms of program design but tailored marketing and partnerships to address the unique local conditions and population of each community. ADECA and the Southeast Energy Efficiency Alliance (SEEA) provided overall project management services and common resources to the local program administrator Nexus Energy Center, including contracted services for contractor training, quality assurance testing, data collection and reporting, and compliance. The fundamental components of the AlabamaWISE program included a vertical contractor-based business model; comprehensive energy assessments; third-party quality assurance; rebates for installation of energy saving measures; accessible, low-interest financing; targeted and inbound marketing; Energy Performance Score (EPS) tool to engage and educate homeowners; training for auditors, contractors, and real estate professionals; and online resources for education and program enrollment. Program participants were eligible to receive rebates or financing toward the assessments and upgrades to their home provided they reached at least 20 percent deemed or modeled energy savings. The design of each program focused on addressing several known barriers including: limited homeowner knowledge on the benefits of energy efficiency, lack of financing options, lack of community support for energy efficiency programs, and lack of trained market actors including contractors and real estate professionals. The programs were able to make progress on addressing all of these barriers and were most successful in offering financing options and training market actors. The most challenging barriers proved to be the act of building a market for energy efficiency where none previously existed, convincing homeowners of the value in investing in energy efficiency (and therefore completing retrofits), engaging electric and natural gas utilities to partner on delivery, and achieving the overall project target of 1,365 completed retrofits. The components that proved to be the most valuable to program success were engaged contractor networks that could promote and endorse the program, partnerships with local business and organizations, and the access to rebates, incentives and financing mechanisms. The programs were successful in building relationships with a variety of community participants including: local contractors, Associations of REALTORS, home builders associations, universities, utilities, local and state governments, and other non-profit organizations. Throughout this program, 933 building audits and 795 building retrofits were completed making homes in Alabama more comfortable, less expensive to operate, more valuable to the marketplace, and safer and healthier for families. Continuing on this momentum, Nexus Energy Center plans to continue operating and expanding operations in Alabama as a Home Performance with ENERGY STAR sponsor and will continue to provide energy services and education to communities in Alabama.
The general system design for the Mark 4-A Deep Space Network to be implemented in the Networks Consolidation Program is discussed. The arrangement and complement of antennas and the list of subsystem equipment at the Signal Processing Center are described.
Wider use of ceramic matrix composites (CMC) will require the development of advanced structural analysis technologies. The use of an interactive model to predict the time-independent reliability of a component subjected to multiaxial loads is discussed. The deterministic, three-parameter Willam-Warnke failure criterion serves as the theoretical basis for the reliability model. The strength parameters defining the model are assumed to be random variables, thereby transforming the deterministic failure criterion into a probabilistic criterion. The ability of the model to account for multiaxial stress states with the same unified theory is an improvement over existing models. The new model was coupled with a public-domain finite element program through an integrated design program. This allows a design engineer to predict the probability of failure of a component. A simple structural problem is analyzed using the new model, and the results are compared to existing models.
Development of the F/48, F/96 Planetary Camera for the Large Space Telescope is discussed. Instrument characteristics, optical design, and CCD camera submodule thermal design are considered along with structural subsystem and thermal control subsystem. Weight, electrical subsystem, and support equipment requirements are also included.
Columbia Power Technologies, Inc. (CPwr) had requested that NREL, through the Small Business Voucher Program, assist in the measurement of mechanical loads experienced by their StingRAY Wave Energy Converter during deployment.
We applied a three-step process, abstracting and analyzing program budgets to examine how Colorectal Cancer Control Program (CRCCP) awardees are structuring their programs and to assess the fidelity of program design to the CRCCP public health model. We reviewed 23 state, one tribal organization, and six university awardee budgets. We assessed resource allocations, staffing structures, and contracted partners and their activities. Awardees allocated 83% of all funds to contracts and personnel. Program managers were the most budgeted personnel type across three measures: number of people, full-time equivalency, and personnel costs. Awardees not only contracted with health care systems and clinics (39% of all contracts) but also contracted other partner types. Contractors were mainly funded to implement evidence-based interventions (25%) and conduct evaluation (24%). Program design varied among awardees in the number of staff (0–22), number of full-time equivalencies (0–5.4), and the number of contracts (1–11) budgeted. State awardees budgeted more resources to contracts, compared with university awardees (57% vs. 31%), while universities budgeted more for total personnel costs (41% vs. 30%). We learned that awardees designed their programs with fidelity to the CRCCP model. Although implementation approaches varied, overall results suggest implementation requires a combination of internal capacities and contracted partners. Budgets provide opportunities to use already existing program data to evaluate program design, partnerships, and planned activities.
The purpose of this study was to provide science-based information to practitioners and managers of restoration projects in the Columbia Estuary Ecosystem Restoration Program (CEERP) regarding aspects of restoration techniques that currently pose known challenges and uncertainties. The CEERP is a program of the Bonneville Power Administration (BPA) and the U.S. Army Corps of Engineers (Corps), Portland District, in collaboration with the National Marine Fisheries Service and five estuary sponsors implementing restoration. The estuary sponsors are Columbia Land Trust, Columbia River Estuary Study Taskforce, Cowlitz Tribe, Lower Columbia Estuary Partnership, and Washington Department of Fish and Wildlife. The scope of the research conducted during federal fiscal year 2015 included three aspects of hydrologic reconnection that were selected based on available scientific information and feedback from restoration practitioners during project reviews: the design of mounds (also called hummocks, peninsulas, or berms); the control of reed canarygrass (Phalaris arundinaceae); and aspects of channel network design related to habitat connectivity for juvenile salmonids.
Computer program determines the useful strength of a thin-walled shell once it has been wrinkled. It can be used as an analytical tool by designers to determine how much wrinkling or deformation a shell can withstand when subjected to axial compression and bending loads.
The NASA Johnson Space Center's X-38 program designed a new backup parachute system to recover the 25,000 lb X-38 prototype for the Crew Return Vehicle spacecraft. Due to weight and cost constraints, the main backup parachute design incorporated rapid and low cost fabrication techniques using off-the-shelf materials. Near the vent, the canopy was constructed of continuous ribbons, to provide more damage tolerance. The remainder of the canopy was a constructed with a continuous ringslot design. After cancellation of the X-38 program, the parachute design was resized, built, and drop tested for Natick Soldiers Center's Low Velocity Air Drop (LVAD) program to deliver cargo loads up to 22,000 lbs from altitudes as low as 500 feet above the ground. Drop tests results showed that the 500-foot LVAD parachute deployment conditions cause severe skirt inversion and inflation problems for large parachutes. The bag strip occurred at a high angle of attack, causing skirt inversion before the parachute could inflate. The addition of a short reefing line prevented the skirt inversion. Using a lower porosity in the vent area, than is normally used in large parachutes, improved inflation. The drop testing demonstrated that the parachute design could be refined to meet the requirements for the 500-foot LVAD mission.
Activities reported include completion of the program design tasks, resolution of a high fiber volume problem and resumption of specimen fabrication, fixture fabrication, and progress on the analysis methodology and definition of the typical aircraft environment. Program design activities including test specimens, specimen holding fixtures, flap-track fairing tailcones, and ground exposure racks were completed. The problem experienced in obtaining acceptable fiber volume fraction results on two of the selected graphite epoxy material systems was resolved with an alteration to the bagging procedure called out in BAC 5562. The revised bagging procedure, involving lower numbers of bleeder plies, produces acceptable results. All required laminates for the contract have now been laid up and cured. Progress in the area of analysis methodology has been centered about definition of the environment that a commercial transport aircraft undergoes. The selected methodology is analagous to fatigue life assessment.
The program method is based on a mean-diameter flow analysis. Input design requirements include power or pressure ratio, flow, temperature, pressure, and speed. Turbine designs are generated for any specified number of stages and for any of three types of velocity diagrams (symmetrical, zero exit swirl, or impulse). Exit turning vanes can be included in the design. Program output includes inlet and exit annulus dimensions, exit temperature and pressure, total and static efficiencies, blading angles, and last-stage critical velocity ratios. The report presents the analysis method, a description of input and output with sample cases, and the program listing.
Through the Earth Observation Commercial Applications Program (EOCAP) at Stennis Space Center, Applied Analysis, Inc. developed a new tool for analyzing remotely sensed data. The Applied Analysis Spectral Analytical Process (AASAP) detects or classifies objects smaller than a pixel and removes the background. This significantly enhances the discrimination among surface features in imagery. ERDAS, Inc. offers the system as a modular addition to its ERDAS IMAGINE software package for remote sensing applications. EOCAP is a government/industry cooperative program designed to encourage commercial applications of remote sensing. Projects can run three years or more and funding is shared by NASA and the private sector participant. Through the Earth Observation Commercial Applications Program (EOCAP), Ocean and Coastal Environmental Sensing (OCENS) developed SeaStation for marine users. SeaStation is a low-cost, portable, shipboard satellite groundstation integrated with vessel catch and product monitoring software. Linked to the Global Positioning System, SeaStation provides real time relationships between vessel position and data such as sea surface temperature, weather conditions and ice edge location. This allows the user to increase fishing productivity and improve vessel safety. EOCAP is a government/industry cooperative program designed to encourage commercial applications of remote sensing. Projects can run three years or more and funding is shared by NASA and the private sector participant.
Precise measurements of Type Ia supernovae (SNe Ia) at low redshifts (z) serve as one of the most viable keys to unlocking our understanding of cosmic expansion, isotropy, and growth of structure. The Dark Energy Bedrock All-Sky Supernovae (DEBASS) program will deliver a uniformly calibrated low-z dataset of more than 400 spectroscopically confirmed SNe Ia in the Southern Hemisphere. DEBASS utilizes the Dark Energy Camera to image supernovae in conjunction with the Wide-Field Spectrograph to gather comprehensive host-galaxy information. By using the same photometric instrument as both the Dark Energy Survey (DES) and the DECam Local Volume Exploration Survey, DEBASS not only benefits from a robust photometric pipeline and well-calibrated images across the Southern sky, but can replace the historic and external low-z samples that were used in the final DES supernova analysis. In this paper, along with a companion paper, we present an early data release of 77 DEBASS SNe within the DES footprint. We introduce the DEBASS program, discuss its scientific goals and the advantages it offers for supernova cosmology, and present our initial results demonstrating data quality. With this early data release, we find a robust median absolute standard deviation of Hubble diagram residuals of ∼0.10 mag and an initial measurement of the host-galaxy mass step of 0.06 ± 0.04 mag, both before performing bias corrections. This low scatter shows the promise of a low-z SN Ia program with a well-calibrated telescope and high signal-to-noise ratio across multiple bands.