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At least 451 records · Page 25

AmeriFlux FLUXNET-1F US-ORv Olentangy River Wetland Research Park

This is the AmeriFlux Management Project (AMP) created FLUXNET-1F version of the carbon flux data for the site US-ORv Olentangy River Wetland Research Park. This is the FLUXNET version of the carbon flux data for the site US-ORv Olentangy River Wetland Research Park produced by applying the standard ONEFlux (1F) software. Site Description - The ORWRP site is a 21-ha large-scale, long-term wetland campus facility that is owned by Ohio State University. It is designed to provide teaching, research, and service related to wetland and river science and ecological engineering. The site has been developed in several phases: Phase 1 (1992 - 1994) - Construction of two 2.5-acre deepwater marshes and a river water delivery system began, with pumps installed on the floodplain to bring water from the Olentangy River. In May 1994, one wetland was planted with marsh vegetation, while the other remained as an unplanted control; Phase 2 (1994 - 1999) - Development of a research and teaching infrastructure took place with the construction of boardwalks, a pavilion, and a compound. The creation of the 7-acre naturally flooded oxbow was also included; Phase 3 (2000 - 2003) - As a research building was created, three additional wetlands were created in the vicinity of the building, including a stormwater wetland that receives runoff from the roof of the building; Phase 4 - The current phase involves research access to the Olentangy River.

Bohrer, Gil↗

AmeriFlux US-DBk Berkeley Way West

This is the AmeriFlux version of the carbon flux data for the site US-DBk Berkeley Way West. Site Description - This tower is located in dowtown Berkeley, CA on the roof of Berkeley Way West, an 8 story building. The surrounding area is urbanized and includes a major commercial corridor, residential areas, and the UC Berkeley campus within 1 km of the site. Multi-unit residential construction activities took place near the site on an intermittent basis throughout tower operation.

Goldstein, Allen [UC Berkeley]↗

What's in a Name? Developing a Standardized Taxonomy for HVAC System Faults

Faults occurring in heating, ventilation and air-conditioning (HVAC) systems have significantly negative impacts on building energy consumption, occupant comfort, and indoor air quality. In the past thirty years, extensive research has been conducted on fault detection and diagnostics (FDD) methods, and there are now dozens of commercially available FDD software tools. Growing adoption of FDD tools has the potential to generate a massive and useful data set on fault characteristics. However, the lack of a unifying taxonomy is a significant barrier to efficient analysis and evaluation of FDD outputs. Therefore, there is a strong need to develop a robust taxonomy which can better represent and interpret FDD output data. This paper documents the development of a unifying taxonomy for HVAC system faults in commercial buildings, with initial focus on air handling units, variable air volume terminal units, and roof top unit systems. The developed fault taxonomy employs both a physical hierarchy of HVAC equipment and a cause-effect relationship model as tools to better understand and support root cause analysis for HVAC faults. A variable air volume terminal unit is used as an example to demonstrate the application of the developed fault taxonomy. The taxonomy has short-term application in a major U.S. study on fault prevalence, and promises longer term benefits to FDD software developers and building operators by creating a foundation for improved approaches to identifying and resolving HVAC faults.

Chen, Yimin↗

Simulation of Photovoltaic Power Output for the Salt River Project Integration Study

One year of power output was simulated at one-minute intervals for each of fourteen hypothetical utility-scale photovoltaic power plants and for the aggregate power output from a large number of distribution-connected photovoltaic systems. For utility-scale plants, the simulation first constructs one-year time series of global horizontal irradiance at one-minute intervals at each plant location, and a performance model translates irradiance and weather information to AC output power. Distribution-connected photovoltaic systems comprise a variety of system configurations: residential-scale rooftop systems at various tilts; commercial-scale flat-roof mounted systems; and commercial-scale ground-mounted tracked systems. For distribution-connected PV systems, the simulation estimates the time series of spatially-averaged irradiance for the region containing the systems, and the performance model is employed to estimate power aggregate power from all systems. The simulation results are validated by comparing statistics for the time series of irradiance with statistics for measured irradiance within the region.

14 SOLAR ENERGY↗

Super Energy Efficiency Design (S.E.E.D.) Home Evaluation

This report describes the results of evaluation by the Alliance for Residential Building Innovation (ARBI) Building America team of the 'Super Energy Efficient Design' (S.E.E.D) home, a 1,935 sq. ft., single-story spec home located in Tucson, AZ. This prototype design was developed with the goal of providing an exceptionally energy efficient yet affordable home and includes numerous aggressiveenergy features intended to significantly reduce heating and cooling loads such as structural insulated panel (SIP) walls and roof, high performance windows, an ERV, an air-to-water heat pump with mixed-mode radiant and forced air delivery, solar water heating, and rooftop PV. Source energy savings are estimated at 45% over the Building America B10 Benchmark. System commissioning, short termtesting, long term monitoring and detailed analysis of results was conducted to identify the performance attributes and cost effectiveness of the whole house measure package.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DRI Renewable Energy Center

The primary objective of this project was to utilize a flexible, energy-efficient facility, called the DRI Renewable Energy Experimental Facility (REEF) to support various renewable energy research and development (R&D) efforts, along with education and outreach activities. The REEF itself consists of two separate buildings: (1) a 1200-ft2 off-grid capable house and (2) a 600-ft2 workshop/garage to support larger-scale experimental work. Numerous enhancements were made to DRI's existing renewable power generation systems, and several additional components were incorporated to support operation of the REEF House. The power demands of this house are satisfied by integrating and controlling PV arrays, solar thermal systems, wind turbines, an electrolyzer for renewable hydrogen production, a gaseous-fuel internal combustion engine/generator set, and other components. Cooling needs of the REEF House are satisfied by an absorption chiller, driven by solar thermal collectors. The REEF Workshop includes a unique, solar air collector system that is integrated into the roof structure. This system provides space heating inside the Workshop, as well as a hot water supply. The Workshop houses a custom-designed process development unit (PDU) that is used to convert woody biomass into a friable, hydrophobic char that has physical and chemical properties similar to low grade coal. Besides providing sufficient space for operation of this PDU, the REEF Workshop supplies hot water that is used in the biomass treatment process. The DRI-REEF serves as a working laboratory for evaluating and optimizing the performance of renewable energy components within an integrated, residential-like setting. The modular nature of the system allows for exploring alternative configurations and control strategies. This experimental test bed is also highly valuable as an education and outreach tool both in providing an infrastructure for student research projects, and in highlighting renewable energy features to the public.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Reducing Thermal Losses and Gains With Buried and Encapsulated Ducts in Hot-Humid Climates

Thermal losses and gains from ductwork installed in unconditioned spaces—such as attics, crawl spaces, and garages—can contribute significantly to the overall heating and cooling loads of single-family residential buildings, with estimated duct losses ranging from 10%–45 %. The impact is particularly severe in hot climates where air conditioning dominates and extensive duct systems are typically located in hot attics. The duct system inefficiencies are greatest at peak demand conditions when the attic is hottest and run times are the highest. The thermal losses and gains at the three single-story houses in Florida monitored in this study accounted for 15%–35% of the annual pre-retrofit heating and cooling energy use and 6%–25% of the total pre-retrofit annual utility bill. Even though a number of existing methods can effectively move ducts into the conditioned space, they are not currently being widely implemented. Physically locating the ducts within the conditioned space is most often applicable only to new construction projects and requires planning during design. Attics can be insulated at the roof deck with closed-cell polyurethane foam (ccSPF) to reduce duct losses and infiltration rates, but this method has high up-front costs and the potential to increase loads on the building enclosure. In hot-dry climates, attic duct systems can be buried under loose-fill insulation at a significantly lower cost to reduce thermal loads. In hot-humid climates, however, condensation on the duct jacket can occur when the humidity in the attic is high.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Establishing a Comprehensive Wind Energy Program

This project was directed at establishing a comprehensive wind energy program in Indiana, including both educational and research components. A graduate/undergraduate course ME-514 - Fundamentals of Wind Energy has been established and offered and an interactive prediction of VAWT performance developed. Vertical axis wind turbines for education and research have been acquired, instrumented and installed on the roof top of a building on the Calumet campus and at West Lafayette (Kepner Lab). Computational Fluid Dynamics (CFD) calculations have been performed to simulate these urban wind environments. Also, modal dynamic testing of the West Lafayette VAWT has been performed and a novel horizontal axis design initiated. The 50-meter meteorological tower data obtained at the Purdue Beck Agricultural Research Center have been analyzed and the Purdue Reconfigurable Micro Wind Farm established and simulations directed at the investigation of wind farm configurations initiated. The virtual wind turbine and wind turbine farm simulation in the Visualization Lab has been initiated.

17 WIND ENERGY↗

Airborne Projection of Burning Embers – Planning and Controls for Los Alamos National Laboratory Facilities

As a result of the Las Conchas Fire, the Department of Energy in correspondence SO:32CK 372899 (DOE 2011) requested that LANS take the following action: Evaluate the Las Conchas fire experience and other data on airborne projection of burning embers and the appropriate planning and controls for Los Alamos National Laboratory (LANL) facilities, including nuclear and high hazard facilities. This paper addresses the DOE action by evaluating 1) the meteorology at the time of the accident and implications for new wild land fires; 2) the ability of LANL facilities to withstand fires as a result of burning embers, and 3) LANL programs in place to mitigate the effects of wild land fires. The spread of fire as a result of burning embers is a known and important mechanism. Both empirical and computational studies have been performed, and it is recognized that these studies should continue (Kim 2009, Koo 2010, Sardoy 2007). Due to the locale and environs of LANL, burning brands or embers from forest fires are a credible risk at LANL. With the exception of the Area G TRU Waste Facility, LANL nuclear facilities have fire resistant exteriors with UL Class A roofs. Waste at Area G is stored in fire resistant containers. The laboratory has comprehensive Emergency Operations and Fire Protection Programs, which includes assessing wildland fire risk and mitigating the spread of fires, for example, by maintaining fire breaks and additional defensible buffer areas free of combustibles around LANL facilities and limits on combustible loading. Vegetation is cut-back to at least national consensus standards on a regular basis around nuclear facilities. Fire Department services are provided by Los Alamos County through an agreement with the Department of Energy. The interface between the Fire Department and LANL during emergencies is the Emergency Operations Division. The ability of LANL facilities to withstand a wildland fire was tested by both the Cerro Grande fire in 2000 as well as the Las Conchas fire. No nuclear or high-hazard facilities were damaged even though the Cerro Grande fire burned around a number of the facilities. Since then, the laboratory has strengthened programs to protect against wildland fires.

99 GENERAL AND MISCELLANEOUS↗

Affordable Cold Climate Infill Housing with Hybrid Insulation Approach, Wyandotte, Michigan (Fact Sheet)

Even builders who are relatively new to energy-efficient construction can consistently reach a target whole house airtightness of 1.5 air changes per hour at 50 Pascals (ACH50) with high R-value enclosures that use a hybrid insulation approach. The City of Wyandotte, Michigan, started a construction program in 2010 to build affordable, energy-efficient homes on lots in existing neighborhoods. A goal of the program was to engage local builders in energy-efficient construction and be able to deliver the new houses for less than $100/ft2. By the end of 2012, approximately 25 new houses were built by five local builders under this program. To help builders consistently achieve the airtightness target, a local architect worked with researchers from Building Science Corporation, a U.S. Department of Energy Building America team, to develop a technology specification with several key pieces. A high R-value wall and roof assembly made use of 2 ?6 advanced framing and a hybrid insulation approach that included insulating sheathing to control thermal bridging and closed cell spray polyurethane foam insulation (ccSPF) for its airtightness and vapor control benefits. This approach allows the air barrier to be completed and tested before any finishing work occurs, ensuring that problems are spotted and corrected early in the construction process.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Measure Guideline: Implementing a Plenum Truss for a Compact Air Distribution System

This Measure Guideline presents the steps to implement a compact duct system inside an attic bulkhead (plenum truss) of a one-story, slab-on-grade (SOG) home. In a compact duct design, ductwork runs are reduced in length to yield a smaller and more compact duct system. Less energy will be lost through ductwork if the ducts are contained within the thermal enclosure of the house. These measures are intended for the production builder working to meet the 2012 International Energy Conservation Code (IECC) requirements and keep the ductwork within the thermal enclosure of the house. This measure of bringing the heating, ventilation and air conditioning (HVAC) equipment and ductwork within the thermal enclosure of the house is appropriate for the builder wishing to avoid cathedralizing the insulation in the attic space (i.e., locating it at the underside of the roof deck rather than along the attic floor) or adding dropped soffits.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

PVWatts ® Calculator: India (Fact Sheet)

The PVWatts ® Calculator for India was released by the National Renewable Energy Laboratory in 2013. The online tool estimates electricity production and the monetary value of that production of grid-connected roof- or ground-mounted crystalline silicon photovoltaics systems based on a few simple inputs. This factsheet provides a broad overview of the PVWatts ® Calculator for India.

14 SOLAR ENERGY↗

City of Camden, New Jersey Program offering widespread energy recovery (power): Final report

The Camden Residential POWER Program, Program Offering Widespread Energy Recovery, is a program designed to benefit Camden homeowners, stabilize neighborhoods and put local contractors to work. Camden POWER granted up to $18,600 to fund energy efficient home improvements and necessary life/safety rehabilitation repairs. The program was designed as a self-sustaining, neighborhood approach to bringing long-term energy and financial savings to the community. Valuable home upgrades were completed, including high-efficiency furnaces, hot water heaters, insulation, insulated roofs and blower door guided air-sealing. The goal of all improvements were to reduce energy consumption, lower utility bills, improve property values and promote neighborhood stabilization.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Nexus EnergyHomes, Frederick, Maryland (Fact Sheet)

With this new home - which achieved the highest rating possible under the National Green Building Standard - Nexus EnergyHomes demonstrated that green and affordable can go hand in hand. The mixed-humid climate builder, along with the U.S. Department of Energy Building America team Partnership for Home Innovation, embraced the challenge to create a new duplex home in downtown Frederick, Maryland, that successfully combines affordability with state-of-the-art efficiency and indoor environmental quality. To limit costs, the builder designed a simple rectangular shape and kept interesting architectural features such as porches outside the building's structure. This strategy avoided the common pitfall of creating potential air leakage where architectural features are connected to the structure before the building is sealed against air infiltration. To speed construction and limit costs, the company chose factory-assembled components such as structural insulated panel walls and floor and roof trusses. Factory-built elements were key in achieving continuous insulation around the entire structure. Open-cell spray foam at the rim joist and attic roofline completed the insulation package, and kept the heating, ventilating, and air-conditioning system in conditioned space.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Analysis of the Chinese Market for Building Energy Efficiency

China will account for about half of the new construction globally in the coming decade. Its floorspace doubled from 1996 to 2011, and Chinese rural buildings alone have as much floorspace as all of U.S. residential buildings. Building energy consumption has also grown, increasing by over 40% since 1990. To curb building energy demand, the Chinese government has launched a series of policies and programs. Combined, this growth in buildings and renovations, along with the policies to promote green buildings, are creating a large market for energy efficiency products and services. This report assesses the impact of China’s policies on building energy efficiency and on the market for energy efficiency in the future. The first chapter of this report introduces the trends in China, drawing on both historical analysis, and detailed modeling of the drivers behind changes in floorspace and building energy demand such as economic and population growth, urbanization, policy. The analysis describes the trends by region, building type and energy service. The second chapter discusses China’s policies to promote green buildings. China began developing building energy codes in the 1980s. Over time, the central government has increased the stringency of the code requirements and the extent of enforcement. The codes are mandatory in all new buildings and major renovations in China’s cities, and they have been a driving force behind the expansion of China’s markets for insulation, efficient windows, and other green building materials. China also has several other important policies to encourage efficient buildings, including the Three-Star Rating System (somewhat akin to LEED), financial incentives tied to efficiency, appliance standards, a phasing out of incandescent bulbs and promotion of efficient lighting, and several policies to encourage retrofits in existing buildings. In the third chapter, we take “deep dives” into the trends affecting key building components. This chapter examines insulation in walls and roofs; efficient windows and doors; heating, air conditioning and controls; and lighting. These markets have seen significant growth because of the strength of the construction sector but also the specific policies that require and promote efficient building components. At the same time, as requirements have become more stringent, there has been fierce competition, and quality has at time suffered, which in turn has created additional challenges. Next we examine existing buildings in chapter four. China has many Soviet-style, inefficient buildings built before stringent requirements for efficiency were more widely enforced. As a result, there are several specific market opportunities related to retrofits. These fall into two or three categories. First, China now has a code for retrofitting residential buildings in the north. Local governments have targets of the number of buildings they must retrofit each year, and they help finance the changes. The requirements focus on insulation, windows, and heat distribution. Second, the Chinese government recently decided to increase the scale of its retrofits of government and state-owned buildings. It hopes to achieve large scale changes through energy service contracts, which creates an opportunity for energy service companies. Third, there is also a small but growing trend to apply energy service contracts to large commercial and residential buildings. This report assesses the impacts of China’s policies on building energy efficiency. By examining the existing literature and interviewing stakeholders from the public, academic, and private sectors, the report seeks to offer an in-depth insights of the opportunities and barriers for major market segments related to building energy efficiency. The report also discusses trends in building energy use, policies promoting building energy efficiency, and energy performance contracting for public building retrofits.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Solar Panels on Hudson County Facilities

This project involved the installation of an 83 kW grid-connected photovoltaic system tied into the energy management system of Hudson County's new 60,000 square foot Emergency Operations and Command Center and staff offices. Other renewable energy features of the building include a 15 kW wind turbine, geothermal heating and cooling, natural daylighting, natural ventilation, gray water plumbing system and a green roof. The County intends to seek Silver LEED certification for the facility.

Photovoltaic↗

Porflow Modeling Supporting the FY13 Saltstone Special Analysis

PORFLOW modeling supporting the concurrent Saltstone FY13 Special Analysis (SA) is described in this report. The present simulations are based on the 2009 Performance Assessment and subsequent modeling to support a response to NRC Request for Additional Information PA-8. Notable changes to the baseline PA-8 model include revised degradation of cementitious materials and associated hydraulic properties, inclusion of floor joints and roof support columns in model representations, and a revised Tc-99 shrinking-core model to implement combined redox and solubility controls. Also presented are new and further justifications for key model assumptions, and verification test cases for selected model attributes. Results are presented for the nominal value simulation case, a flow sensitivity parametric study, and Tc-99 transport sensitivity cases. Further discussion of PORFLOW model setup and simulation results is presented in the Saltstone FY13 SA, including dose results.

Cementitious Materials↗

Moisture Risk in Unvented Attics Due to Air Leakage Paths

IBACOS completed an initial analysis of moisture damage potential in an unvented attic insulated with closed-cell spray polyurethane foam. To complete this analysis, the research team collected field data, used computational fluid dynamics to quantify the airflow rates through individual airflow (crack) paths, simulated hourly flow rates through the leakage paths with CONTAM software, correlated the CONTAM flow rates with indoor humidity ratios from Building Energy Optimization software, and used Warme und Feuchte instationar Pro two-dimensional modeling to determine the moisture content of the building materials surrounding the cracks. Given the number of simplifying assumptions and numerical models associated with this analysis, the results indicate that localized damage due to high moisture content of the roof sheathing is possible under very low airflow rates. Reducing the number of assumptions and approximations through field studies and laboratory experiments would be valuable to understand the real-world moisture damage potential in unvented attics.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗