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Introducing an Absolute Cavity Pyrgeometer for Improving the Atmospheric Longwave Irradiance Measurement
Advancing climate change research requires accurate and traceable measurement of the atmospheric longwave irradiance. Current measurement capabilities are limited to an estimated uncertainty of larger than +/- 4 W/m2 using the interim World Infrared Standard Group (WISG). WISG is traceable to the Systeme international d'unites (SI) through blackbody calibrations. An Absolute Cavity Pyrgeometer (ACP) is being developed to measure absolute outdoor longwave irradiance with traceability to SI using the temperature scale (ITS-90) and the sky as the reference source, instead of a blackbody. The ACP was designed by NREL and optically characterized by the National Institute of Standards and Technology (NIST). Under clear-sky and stable conditions, the responsivity of the ACP is determined by lowering the temperature of the cavity and calculating the rate of change of the thermopile output voltage versus the changing net irradiance. The absolute atmospheric longwave irradiance is then calculated with an uncertainty of +/- 3.96 W/m2 with traceability to SI. The measured irradiance by the ACP was compared with the irradiance measured by two pyrgeometers calibrated by the World Radiation Center with traceability to the WISG. A total of 408 readings was collected over three different clear nights. The calculated irradiance measured by the ACP …
Date:
August 1, 2012
Creator:
Reda, I.; Hansen, L. & Zeng, J.
System:
The UNT Digital Library
Renewable Electricity Futures
This presentation library summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. It was presented at the 2012 RE AMP Annual Meeting. RE-AMP is an active network of 144 nonprofits and foundations across eight Midwestern states working on climate change and energy policy with the goal of reducing global warming pollution economy-wide 80% by 2050.
Date:
August 1, 2012
Creator:
Mai, Trieu
System:
The UNT Digital Library
Renewable Electricity Futures
This presentation library summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. It was presented at Wind Powering America States Summit. The Summit, which follows the American Wind Energy Association's (AWEA's) annual WINDPOWER Conference and Exhibition, provides state Wind Working Groups, state energy officials, U.S. Energy Department and national laboratory representatives, and professional and institutional partners an opportunity to review successes, opportunities, and challenges for wind energy and plan future collaboration.
Date:
August 1, 2012
Creator:
DeMeo, E.
System:
The UNT Digital Library
Renewable Electricity Futures
This presentation library summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. It was presented in a webinar given by the California Energy Commission.
Date:
August 1, 2012
Creator:
Hand, M. Maureen
System:
The UNT Digital Library
Renewable Electricity Futures
This presentation summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. This presentation was presented in a Wind Powering America webinar on August 15, 2012 and is now available through the Wind Powering America website.
Date:
August 1, 2012
Creator:
Mai, Trieu
System:
The UNT Digital Library
Renewable Electricity Futures
This presentation summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. It was presented in a Power Systems Engineering Research Center webinar on September 4, 2012.
Date:
August 1, 2012
Creator:
Mai, Trieu
System:
The UNT Digital Library
Renewable Electricity Futures
This presentation library summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. It was presented in an Union of Concerned Scientists webinar on June 12, 2012.
Date:
August 1, 2012
Creator:
Hand, M. Maureen & Mai, Trieu
System:
The UNT Digital Library
Renewable Electricity Futures
This presentation library summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. It was presented to the 2012 Western Conference of Public Service Commissioners, during their June, 2012, meeting. The Western Conference of Public Service Commissioners is a regional association within the National Association of Regulatory Utility Commissioners (NARUC).
Date:
August 1, 2012
Creator:
Hand, M. Maureen
System:
The UNT Digital Library
U.S. Electric Power Futures: Preliminary Results
This presentation shows key findings of an effort to simulate the evolution of the U.S. power sector under a number of policy and technology scenarios using the Regional Energy Deployment System (ReEDS) Model.
Date:
August 1, 2012
Creator:
Lopez, A.; Logan, J. & Mai, T.
System:
The UNT Digital Library
Estimate of the Geothermal Energy Resource in the Major Sedimentary Basins in the United States
Because most sedimentary basins have been explored for oil and gas, well logs, temperatures at depth, and reservoir properties such as depth to basement and formation thickness are well known. The availability of this data reduces exploration risk and allows development of geologic exploration models for each basin. This study estimates the magnitude of recoverable geothermal energy from 15 major known U.S. sedimentary basins and ranks these basins relative to their potential. The total available thermal resource for each basin was estimated using the volumetric heat-in-place method originally proposed by (Muffler, 1979). A qualitative recovery factor was determined for each basin based on data on flow volume, hydrothermal recharge, and vertical and horizontal permeability. Total sedimentary thickness maps, stratigraphic columns, cross sections, and temperature gradient information was gathered for each basin from published articles, USGS reports, and state geological survey reports. When published data were insufficient, thermal gradients and reservoir properties were derived from oil and gas well logs obtained on oil and gas commission databases. Basin stratigraphy, structural history, and groundwater circulation patterns were studied in order to develop a model that estimates resource size, temperature distribution, and a probable quantitative recovery factor.
Date:
September 1, 2012
Creator:
Esposito, A.; Porro, C.; Augustine, C. & Roberts, B.
System:
The UNT Digital Library
Impacts from Deployment Barriers on the United States Wind Power Industry: Overview & Preliminary Findings
Regardless of cost and performance some wind projects are unable to proceed to commissioning as a result of deployment barriers. Principal deployment barriers in the industry today include: wildlife, public acceptance, access to transmission, and radar. To date, methods for understanding these non-technical barriers have failed to accurately characterize the costs imposed by deployment barriers and the degree of impact to the industry. Analytical challenges include limited data and modeling capabilities. Changes in policy and regulation, among other factors, also add complexity to analysis of impacts from deployment barriers. This presentation details preliminary results from new NREL analysis focused on quantifying the impact of deployment barriers on the wind resource of the United States, the installed cost of wind projects, and the total electric power system cost of a 20% wind energy future. In terms of impacts to wind project costs and developable land, preliminary findings suggest that deployment barriers are secondary to market drivers such as demand. Nevertheless, impacts to wind project costs are on the order of $100/kW and a substantial share of the potentially developable windy land in the United States is indeed affected by deployment barriers.
Date:
September 1, 2012
Creator:
Lantz, E.; Tegen, S.; Hand, M. & Heimiller, D.
System:
The UNT Digital Library
Impacts of Renewable Generation on Fossil Fuel Unit Cycling: Costs and Emissions
Prepared for the Clean Energy Regulatory Forum III, this presentation looks at the Western Wind and Solar Integration Study and reexamines the cost and emissions impacts of fossil fuel unit cycling.
Date:
September 1, 2012
Creator:
Brinkman, G.; Lew, D. & Denholm, P.
System:
The UNT Digital Library
Infrastructure Analysis Tools: A Focus on Cash Flow Analysis
NREL has developed and maintains a variety of infrastructure analysis models for the U.S. Department of Energy. Business case analysis has recently been added to this tool set. This presentation focuses on cash flow analysis. Cash flows depend upon infrastructure costs, optimized spatially and temporally, and assumptions about financing and revenue. NREL has incorporated detailed metrics on financing and incentives into the models. Next steps in modeling include continuing to collect feedback on regional/local infrastructure development activities and 'roadmap' dynamics, and incorporating consumer preference assumptions on infrastructure to provide direct feedback between vehicles and station rollout.
Date:
September 1, 2012
Creator:
Melaina, M. & Penev, M.
System:
The UNT Digital Library
Renewable Electricity Futures
This presentation summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050.
Date:
September 1, 2012
Creator:
Hand, M. Maureen
System:
The UNT Digital Library
Dew-Point Evaporative Comfort Cooling
Presentation on innovative indirect evaporative cooling technology developed by Coolerado Corporation given at the Rocky Mountain Chapter ASHRAE conference in April 2012.
Date:
October 1, 2012
Creator:
Dean, J.
System:
The UNT Digital Library
Fuel Cell Backup Power Technology Validation
Presentation about fuel cell backup power technology validation activities at the U.S. Department of Energy's National Renewable Energy Laboratory.
Date:
October 1, 2012
Creator:
Kurtz, J.; Sprik, S.; Ramsden, T. & Saur, G.
System:
The UNT Digital Library
NREL's e-Ca Test
Presentation on NREL's e-Ca test.
Date:
October 1, 2012
Creator:
Dameron, A. A.
System:
The UNT Digital Library
Renewable Electricity Futures
This presentation library summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. It is being presented at the Utility Variable-Generation Integration Group Fall Technical Workshop on October 24, 2012.
Date:
October 1, 2012
Creator:
Hand, M. Maureen
System:
The UNT Digital Library
Renewable Electricity Futures
This presentation library summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050.
Date:
October 1, 2012
Creator:
Mai, Trieu
System:
The UNT Digital Library
Scripted Building Energy Modeling and Analysis
Building energy analysis is often time-intensive, error-prone, and non-reproducible. Entire energy analyses can be scripted end-to-end using the OpenStudio Ruby API. Common tasks within an analysis can be automated using OpenStudio Measures. Graphical user interfaces (GUI's) and component libraries reduce time, decrease errors, and improve repeatability in energy modeling.
Date:
October 1, 2012
Creator:
Macumber, D.
System:
The UNT Digital Library
Solar Water Heating
Overview of photovoltaics role with passive solar houses.
Date:
October 1, 2012
Creator:
Walker, A.
System:
The UNT Digital Library
Supply Chain Dynamics of Tellurium (Te), Indium (In), and Gallium (Ga) Within the Context of PV Module Manufacturing Costs
Analysis discussing the cost models and supply chains of various PV technologies.
Date:
October 1, 2012
Creator:
Woodhouse, M.; Goodrich, A.; James, T.; Margolis, R.; Eggert, R. & Lokanc, M.
System:
The UNT Digital Library
Technology and Climate Trends in PV Module Degradation
To sustain the commercial success of photovoltaic (PV) technology it is vital to know how power output decreases with time. Unfortunately, it can take years to accurately measure the long-term degradation of new products, but past experience on older products can provide a basis for prediction of degradation rates of new products. An extensive search resulted in more than 2000 reported degradation rates with more than 1100 reported rates that include some or all IV parameters. In this presentation we discuss how the details of the degradation data give clues about the degradation mechanisms and how they depend on technology and climate zones as well as how they affect current and voltage differently. The largest contributor to maximum power decline for crystalline Si technologies is short circuit current (or maximum current) degradation and to a lesser degree loss in fill factor. Thin-film technologies are characterized by a much higher contribution from fill factor particularly for humid climates. Crystalline Si technologies in hot & humid climates also display a higher probability to show a mixture of losses (not just short circuit current losses) compared to other climates. The distribution for the module I-V parameters (electrical mismatch) was found to change with …
Date:
October 1, 2012
Creator:
Jordan, D.; Wohlgemuth, J. & Kurtz, S.
System:
The UNT Digital Library
U.S. Balance-of-Station Cost Drivers and Sensitivities
With balance-of-system (BOS) costs contributing up to 70% of the installed capital cost, it is fundamental to understanding the BOS costs for offshore wind projects as well as potential cost trends for larger offshore turbines. NREL developed a BOS model using project cost estimates developed by GL Garrad Hassan. Aspects of BOS covered include engineering and permitting, ports and staging, transportation and installation, vessels, foundations, and electrical. The data introduce new scaling relationships for each BOS component to estimate cost as a function of turbine parameters and size, project parameters and size, and soil type. Based on the new BOS model, an analysis to understand the non‐turbine costs has been conducted. This analysis establishes a more robust baseline cost estimate, identifies the largest cost components of offshore wind project BOS, and explores the sensitivity of the levelized cost of energy to permutations in each BOS cost element. This presentation shows results from the model that illustrates the potential impact of turbine size and project size on the cost of energy from U.S. offshore wind plants.
Date:
October 1, 2012
Creator:
Maples, B.
System:
The UNT Digital Library