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Are all identically conserved geometric tensors metric variations of actions? A status report
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Analysis of Performance and Efficiency of Conservation Voltage Optimization Considering Load Model Uncertainty
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Conservation laws and conversion efficiency in ultraintense laser-overdense plasma interactions
Particle coupling to the oscillatory and steady-state nonlinear force of an ultraintense laser is studied through analytic modeling and particle-in-cell simulations. The complex interplay between these absorption mechanisms—corresponding, respectively, to “hot” electrons and “hole punching” ions—is central to the viability of many ultraintense laser applications. Yet, analytic work to date has focused only on limiting cases of this key problem. In this paper, we develop a fully relativistic model in 1-D treating both modes of ponderomotive light absorption on equitable theoretical footing for the first time. Using this framework, analytic expressions for the conversion efficiencies into hole punching ions and into hot electrons are derived. Solutions for the relativistically correct hole punching velocity and the hot electron Lorentz factor are also calculated. Excellent agreement between analytic predictions and particle-in-cell simulations is demonstrated, and astrophysical analogies are highlighted.
Erratum: “Irreversible thermodynamics of open chemical networks. I. Emergent cycles and broken conservation laws” [J. Chem. Phys. 141, 024117 (2014)]
No abstract prepared.
Novel technologies for emission reduction complement conservation agriculture to achieve negative emissions from row-crop production
Plants remove carbon dioxide from the atmosphere through photosynthesis. Because agriculture’s productivity is based on this process, a combination of technologies to reduce emissions and enhance soil carbon storage can allow this sector to achieve net negative emissions while maintaining high productivity. Unfortunately, current row-crop agricultural practice generates about 5% of greenhouse gas emissions in the United States and European Union. Here, to reduce these emissions, significant effort has been focused on changing farm management practices to maximize soil carbon. In contrast, the potential to reduce emissions has largely been neglected. Through a combination of innovations in digital agriculture, crop and microbial genetics, and electrification, we estimate that a 71% (1,744 kg CO 2 e/ha) reduction in greenhouse gas emissions from row crop agriculture is possible within the next 15 y. Importantly, emission reduction can lower the barrier to broad adoption by proceeding through multiple stages with meaningful improvements that gradually facilitate the transition to net negative practices. Emerging voluntary and regulatory ecosystems services markets will incentivize progress along this transition pathway and guide public and private investments toward technology development. In the difficult quest for net negative emissions, all tools, including emission reduction and soil carbon storage, must be developed to allow agriculture to maintain its critical societal function of provisioning society while, at the same time, generating environmental benefits.
Energy savings modelling of re-tuning energy conservation measures in large office buildings
Today, many large commercial buildings use sophisticated building automation systems (BASs) to manage a wide range of building equipment. While the capabilities of BASs have increased over time, many buildings still do not fully use the BAS’s capabilities and are not properly commissioned, operated or maintained, which leads to inefficient operation, increased energy use, and reduced lifetimes of the equipment. This paper investigates the energy savings potential of several common HVAC system re-tuning measures on a typical large office building, using the Department of Energy’s building energy modeling software, EnergyPlus. The baseline prototype model uses roughly as much energy as an average large office building in existing building stock, but does not utilize any re-tuning measures. Individual re-tuning measures simulated against this baseline include automatic schedule adjustments, damper minimum flow adjustments, thermostat adjustments, as well as dynamic resets (set points that change continuously with building and/or outdoor conditions) to static pressure, supply-air temperature, condenser water temperature, chilled and hot water temperature, and chilled and hot water differential pressure set points. Six combinations of these individual measures have been formulated – each designed to conform to limitations to implementation of certain individual measures that might exist in typical buildings. All the individual measures and combinations were simulated in 16 climate locations representative of specific U.S. climate zones. The modeling results suggest that the most effective energy savings measures are those that affect the demand-side of the building (air-systems and schedules). Many of the demand-side individual measures were capable of reducing annual total HVAC system energy consumption by over 20% in most cities that were modeled. Supply side measures affecting HVAC plant conditions were only modestly successful (less than 5% annual HVAC energy savings for most cities for all measures). Combining many of the re-tuning measures revealed deep savings potential. Some of the more aggressive combinations revealed 35-75% reductions in annual HVAC energy consumption, depending on climate and building vintage.
Classically and quantum stable emergent universe from conservation laws
It has been recently pointed out by Mithani-Vilenkin [1-4] that certain emergent universe scenarios which are classically stable are nevertheless unstable semiclassically to collapse. Here, we show that there is a class of emergent universes derived from scale invariant two measures theories with spontaneous symmetry breaking (s.s.b) of the scale invariance, which can have both classical stability and do not suffer the instability pointed out by Mithani-Vilenkin towards collapse. We find that this stability is due to the presence of a symmetry in the 'emergent phase', which together with the non linearities of the theory, does not allow that the FLRW scale factor to be smaller that a certain minimum value a {sub 0} in a certain protected region.
Cellulosic feedstock production on Conservation Reserve Program land: potential yields and environmental effects
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Energy Conservation in Distributed Interference as a Guarantee for Detecting a Detector Blinding Attack in Quantum Cryptography
An avalanche single-photon detector blinding attack is one of the methods for quantum hacking of quantum key distribution (QKD) systems. The attack was experimentally demonstrated for both phase- and polarization-encoded QKD systems. During this attack, an eavesdropper knows the entire key, does not produce errors and саnnot be detected. However, the phase encoding has neglected some significant features of the photocount statistics in the receiving party. It is shown in the paper at the level of fundamental principles that this attack changes the photocount statistics and leads to the detection of an eavesdropper. Expressions for the secret key length are obtained for this attack. This does not require any changes in the design and control electronics of the phase-encoded QKD system, and only changes in processing the results of registration of quantum states are sufficient. At the same time, the secret key vulnerability and compromise in polarization-encoded QKD systems is an existing fact rather than a potential menace.
Genomic analysis of methanogenic archaea reveals a shift towards energy conservation
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Marker genes that are less conserved in their sequences are useful for predicting genome-wide similarity levels between closely related prokaryotic strains
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Energy Efficiency and Conservation Block Grant (EECBG) - Better Buildings Neighborhood Program at Greater Cincinnati Energy Alliance: Home Performance with Energy Star® and Better Buildings Performance
The Greater Cincinnati Energy Alliance (Energy Alliance) is a nonprofit economic development agency dedicated to helping Greater Cincinnati and Northern Kentucky communities reduce energy consumption. The Energy Alliance has launched programs to educate homeowners, commercial property owners, and nonprofit organizations about energy efficiency opportunities they can use to drive energy use reductions and financial savings, while extending significant focus to creating/retaining jobs through these programs. The mission of the Energy Alliance is based on the premise that investment in energy efficiency can lead to transformative economic development in a region. With support from seven municipalities, the Energy Alliance began operation in early 2010 and has been among the fastest growing nonprofit organizations in the Greater Cincinnati/Northern Kentucky area. The Energy Alliance offers two programs endorsed by the Department of Energy: the Home Performance with ENERGY STAR® Program for homeowners and the Better Buildings Performance Program for commercial entities. Both programs couple expert guidance, project management, and education in energy efficiency best practices with incentives and innovative energy efficiency financing to help building owners effectively invest in the energy efficiency, comfort, health, longevity, and environmental impact of their residential or commercial buildings. The Energy Alliance has raised over $23 million of public and private capital to build a robust market for energy efficiency investment. Of the $23 million, $17 million was a direct grant from the Department of Energy Better Buildings Neighborhood Program (BBNP). The organization’s investments in energy efficiency projects in the residential and commercial sector have led to well over $50 million in direct economic activity and created over 375,000 hours of labor created or retained. In addition, over 250 workers have been trained through the Building Performance Training Center, a program that was developed and funded by the Energy Alliance and housed at Cincinnati State Technical and Community College. Nearly 100 residential and commercial contractors currently participate in the Energy Alliance’s two major programs, which have together served over 2,800 residential and 100 commercial customers. Additionally, the Energy Alliance established loan programs for homeowners, nonprofits and commercial businesses. The GC-HELP program was established to provide up to ten year low interest, unsecured loans to homeowners to cover the energy efficiency products they purchased through the Energy Alliance approved contractor base. To date the Energy Alliance has financed over $1 million in energy efficiency loans for homeowners, without any loans written off. The nonprofit business community is offered five year, fixed-interest rate loans through the Building Communities Loan Fund of $250,000. Additionally, the Energy Alliance has developed GC-PACE, a commercial financing tool that enables buildings owners to finance their energy upgrades through voluntary property assessments deploying low-interest extended-term capital from the bond market. The Energy Alliance and its partners are actively evaluating additional market-based financing solutions.
Energy Efficiency and Conservation Block Grant (EECBG): Better Buildings Neighborhood Program Final Report
The Neighbor to Neighbor Energy Challenge (N2N) brought together a consortium of 14 leading clean energy rural, suburban, and low income communities throughout Connecticut. N2N was awarded $4.2 million from the U.S. Department of Energy (DOE) competitive BetterBuildings Neighborhood Program on August 10, 2010 to run a two-year pilot program (plus one year of transition and evaluation) (Award No. EMCBC- 00969-10). N2N tested innovative program models and hypotheses for improving Connecticut’s existing residential energy efficiency programs that are overseen by the ratepayer fund board and administered by CT utilities. N2N’s original goal was to engage 10 percent of households in participating communities to reduce their energy usage by 20 percent through energy upgrades and clean energy measures. N2N planned for customers to complete more comprehensive whole-home energy efficiency and clean energy measures and to achieve broader penetration than existing utility-administered regulated programs. Since this was an ARRA award, we report the following figures on job creation in Table 1. Since N2N is not continuing in its current form, we do not provide figures on job retention. Table 1 N2N Job Creation by Quarter Jobs Created 2010 Q4 6.65 2011 Q1 7.13 2011 Q2 4.98 2011 Q3 9.66 2011 Q4 5.43 2012 Q1 11.11 2012 Q2 6.85 2012 Q3 6.29 2012 Q4 6.77 2013 Q1 5.57 2013 Q2 8.35 2013 Q3 6.52 Total 85.31 The N2N team encountered several gaps in the existing efficiency program performance that hindered meeting N2N’s and DOE’s short-term program goals, as well as the State of Connecticut’s long-term energy, efficiency, and carbon reduction goals. However, despite the slow program start, N2N found evidence of increasing upgrade uptake rates over time, due to delayed customer action of one to two years from N2N introduction to completion of deeper household upgrades. Two main social/behavioral principles have contributed to driving deeper upgrades in CT: 1. Word of mouth, where people share their experience with others, which leads to others to take action; and 2. Self-herding, where people follow past behavior, which leads to deeper and deeper actions within individual households.
Feasibility Study of Economics and Performance of Solar Photovoltaics at the TechCity East Campus Resource Conservation and Recovery Act Site in Kingston, New York. A Study Prepared in Partnership with the Environmental Protection Agency for the RE-Powering America's Land Initiative: Siting Renewable Energy on Potentially Contaminated Land and Mine Sites
The U.S. Environmental Protection Agency (EPA), in accordance with the RE-Powering America's Land initiative, selected the TechCity East Campus site in Kingston, New York, for a feasibility study of renewable energy production. The National Renewable Energy Laboratory (NREL) provided technical assistance for this project. The purpose of this study is to assess the site for a possible photovoltaic (PV) system installation and estimate the cost, performance, and site impacts of different PV options. In addition, the report recommends financing options that could assist in the implementation of a PV system at the site.
Feasibility of Renewable Energy Development at Arch Hurley Conservancy District
Abstract Not Provided
Conclusions of Arch Hurley Conservancy District Irrigation Project--Summary
Abstract Not Provided
Refrigeration Playbook. Heat Reclaim; Optimizing Heat Rejection and Refrigeration Heat Reclaim for Supermarket Energy Conservation
The purpose of this playbook and accompanying spreadsheets is to generalize the detailed CBP analysis and to put tools in the hands of experienced refrigeration designers to evaluate multiple applications of refrigeration waste heat reclaim across the United States. Supermarkets with large portfolios of similar buildings can use these tools to assess the impact of large-scale implementation of heat reclaim systems. In addition, the playbook provides best practices for implementing heat reclaim systems to achieve the best long-term performance possible. It includes guidance on operations and maintenance as well as measurement and verification.