A Multiobjective Harmony-Search Algorithm for Building Life-cycle Energy Optimization

Major US electric utility climate pledges have the potential to collectively reduce power sector emissions by one-third

In Australia, dairy cattle account for ~12% of the nation’s agricultural greenhouse-gas (GHG) emissions. Genetic selection has had a positive impact, reducing GHG emissions from dairy systems mainly due to increased production per cow, which has led to (1) requiring fewer cows to produce the same amount of milk and (2) lowering emissions per unit of milk produced (emission intensity). The objective of the present study was to evaluate the consequences of previous and current genetic-selection practices on carbon emissions, using realised and predicted responses to selection for key traits that are included in the Australian national breeding objective. A farm model was used to predict the carbon dioxide equivalent (CO2-eq) emissions per unit change of these traits, while holding all other traits constant. Estimates of the realised change in annual CO2-eq emissions per cow over the past decade were made by multiplying predicted CO2-eq emissions per unit change of each trait under selection by the realised rates of genetic gain in each of those traits. The total impact is estimated to be an increase of 55 kg CO2-eq/cow.year after 10 years of selection. The same approach was applied to future CO2-eq emissions, except predicted rates of genetic gain assumed to occur over the next decade through selection on the Balanced Performance Index (BPI) were used. For an increase of AU$100 in BPI (~10 years of genetic improvement), we predict that the increase of per cow emissions will be reduced to 37 kg CO2-eq/cow.year. Since milk-production traits are a large part of the breeding goal, the GHG emitted per unit of milk produced will reduce as a result of improvements in efficiency and dilution of emissions per litre of milk produced at a rate estimated to be 35.7 g CO2-eq/kg milk solids per year in the past decade and is predicted to reduce to 29.5 g CO2-eq/kg milk solids per year after a conservative 10-year improvement in BPI (AU$100). In fact, cow numbers have decreased over the past decade and production has increased; altogether, we estimate that the net impact has been a reduction of CO2-eq emissions of ~1.0% in total emissions from the dairy industry per year. Using two future scenarios of either keeping the number of cows or amount of product static, we predict that net GHG emissions will reduce by ~0.6%/year of total dairy emissions if milk production remains static, compared with 0.3%/year, if cow numbers remain the same and there is genetic improvement in milk-production traits.

I. INTRODUCTION II. HISTORY OF CLIMATE CHANGE A. The Evolution of Climate Change Policy B. The Domestic Agenda for Combating Climate Change III. CONFRONTING ARTICLE III STANDING A. Developing Standing Jurisprudence B. The Effect of Lujan C. Should the Political Branches Decide? IV. EXAMINING THE CLEAN AIR ACT A. The Chevron Test B. An Analysis of the D.C. Circuit's Opinions in Massachusetts v. EPA 1. Judge Randolph's Majority Opinion 2. Judge Sentelle's Concurrence and Dissent 3. Judge Tatel's Dissent V. PROMOTING REGULATION THROUGH THE CLEAN AIR ACT A. Article III Standing 1. The Akins/Lujan Standard 2. Proposing New Standing Requirements for Global Warming Disputes B. Interpreting the Clean Air Act Provisions 1. Examining Congressional Intent 2. The D.C. Circuit's Mischaracterization of the Clean Air Act C. The Likely Outcome of Massachusetts v. EPA VI. CONCLUSION I. INTRODUCTION On October 20, 1999, the International Center for Technology Assessment (ICTA) and a number of environmental groups petitioned the Environmental Protection Agency (EPA) to regulate certain greenhouse gas (GHG) emissions from new motor vehicles and engines. (2) The organizations argued that section 202(a)(1) of the Clean Air Act (CAA) (3) provided the EPA Administrator with mandatory discretion to regulate GHG emissions. (4) Petitioners contended that statements made on the EPA's website and other documents concluded that the emissions they sought to control may reasonably be anticipated to endanger the public welfare. (5) They also claimed that motor vehicle emissions from the GHGs could be significantly reduced by increasing the fuel economy of vehicles, eliminating tailpipe emissions altogether, or using other current and developing technologies. However, the EPA concluded that it did not possess the legal authority to regulate the GHG emissions and denied their petition. (6) In Massachusetts v. Environmental Protection Agency, (7) the D.C. Circuit addressed the issue of whether the Clean Air Act authorized the EPA Administrator to control GHG emissions of new motor vehicles and engines. A three-judge panel voted 2-1 against reviewing the EPA's decision that it lacked authority under federal law to regulate GHGs. (8) The majority held that the Administrator properly exercised his discretion under section 202(a)(1) in denying the petition for rulemaking. (9) In an en banc hearing, the D.C. Circuit rejected a petition for rehearing. (10) Late last term, the Supreme Court granted certiorari to hear arguments to resolve this controversy. (11) This comment asserts that the CAA authorizes the EPA to regulate GHG emissions from new motor vehicles. The Supreme Court's decision in Chevron USA, Inc. v. Natural Resources Defense Council, Inc. (12) held that if a statute is silent or ambiguous with respect to a specific issue, the question becomes whether the agency's action involves a permissible construction of the statute. Part II of this comment discusses the historical background of climate change policy regarding GHG emissions. Part III focuses on the various environmental law cases addressing the issue of Article III standing. Part IV analyzes the Chevron test and the three opinions by the Massachusetts v. Environmental Protection Agency judges. Part V advances the belief that section 202(a)(1) of the CAA provides mandatory authority and predicts that the Supreme Court will decide that the petitioners possess proper standing and that the EPA is mandated under section 202(a)(1) to regulate GHG emissions. This prediction is based on the Court's jurisprudence regarding Article III standing and the Chevron doctrine, respectively. Part VI concludes that failure to control the production of GHG emissions from new motor vehicles and engines limits the impact of the CAA to protect the public welfare from threats to the environment. …

There is growing urgency to both increase plastic recycling rates and reduce the impact of plastic waste on the environment. Mechanical recycling rates for plastics in the United States have only slightly increased from 6% to 9% between 2000 and 2015 and have plateaued near 9% despite continued efforts to increase the rate. Therefore, evaluation of additional options that can increase recycling rates must occur to establish a comprehensive approach to keeping used plastics in the economy. The advanced recycling (AR) technologies analyzed in this paper have the capability to address the unrecycled plastics, representing a viable future path that can improve the plastic recycling rate and reduce resource use and environmental impacts. A rigorous quantitative assessment has been done of a subset of recent life cycle assessments (LCAs) resulting in thirteen LCAs being selected using criteria based on processing capacity and technology readiness level. Comparisons across those LCAs resulted in a quantitative greenhouse gas (GHG) emissions reduction ranging from −267% to 566% with the implementation of AR technologies. Specifically, mixed plastic (MP) streams converted to polyolefins via pyrolysis produced 185% less carbon dioxide equivalent (CO2eq) emissions compared to conversion to energy for heat and power production. Alternatively, MP processed via pyrolysis produced 267% more CO2eq emissions than landfilling. Importantly, 30 other comparative scenarios were presented by the chosen LCAs as sensitivity analyses, with GHG emissions similarly ranging from increases to reductions, with the preponderance of the data indicating reductions. The various impact categories assessed, in addition to GHG emissions, for the AR technologies ranged from favorable, with the pyrolysis of MP offering a 97% reduction in fossil depletion compared to waste to energy, to unfavorable with the pyrolysis of MP offering a 400% increase in fine particulate matter compared to 30% municipal solid waste incineration and 70% refuse-derived fuel.

Last year, the US Court of Appeals (D.C. Circuit) upheld a series of findings, interpretations, and regulations that the Environmental Protection Agency (EPA) had issued as its first steps to limit the emissions of greenhouse gases under the Clean Air Act. First, EPA had made a finding that emissions of greenhouse gases from motor vehicles cause or contribute to an endangerment to the public health or welfare. Second, to address this endangerment, EPA together with the Department of Transportation, promulgated greenhouse gas emission and fuel efficiency standards for cars and light trucks for model years 2012 through 2016. EPA estimates that these standards will reduce greenhouse gas emissions by approximately 960 million metric tons of CO2 equivalent over the life of these model years. Third, EPA formally reaffirmed its interpretation that the motor vehicle emission standards - by regulating greenhouse gases under the Act - would trigger permitting requirements for greenhouse gas emissions from stationary facilities. These permitting requirements include the installation of best available control technology to reduce greenhouse gas emissions from new or modified facilities. Fourth, EPA issued regulations phasing in these permitting requirements over several years. Rejecting a multitude of challenges, the court upheld all these actions, thus paving the way for EPA to significantly regulate and limit greenhouse gas emissions from motor vehicles and stationary facilities. On 26 June 2012, the prominent US Court of Appeals for the District of Columbia Circuit handed the Barak Obama Administration a decisive, quadruple victory in its efforts to limit greenhouse gas emissions through regulations. The court upheld the finding of the US Environmental Protection Agency (EPA) that greenhouse gas emissions are reasonably anticipated to endanger public health and welfare. The court also upheld EPA regulations and interpretations that will require reductions in greenhouse gas emissions from motor vehicles and large stationary sources. The court reaffirmed its decision, denying a petition for rehearing, on 20 December 2012. The decision paves the way for significant mandatory reductions of greenhouse gas emissions in the US.

A study of the LCA based biofuel supply chain multi-objective optimization model with multi-conversion paths in China

Life cycle cost and GHG emission benefits of electric vehicles in China

The construction and building environment is one of the largest contributors to climate change, greenhouse gas emissions, depletion of natural resources and damage to ecological integrity. Therefore, the use of more sustainable materials in construction is currently of great interest. Structural wood is considered as a versatile renewable material, having an optimal strength-to-weight ratio, insulating properties, low carbon emissions in the operational life cycle and a great abundance in nature. Furthermore, unlike other materials, wood is the only one that stores carbon in its production. The purpose of this project is to evaluate, through the Life Cycle Analysis methodology, the environmental impact of the construction of buildings made of timber compared to reinforced concrete buildings, understanding the environmental benefits and disadvantages of each technology. The results obtained from the comparison of a timber building with its concrete counterpart confirm the feasible benefit of wood in the reduction of carbon emissions and non-renewable energy consumption, as well as other positive aspects such as the reduction of other emissions. By highlighting the benefits and opportunities of wood it is intended to promote the material in construction and the development of more efficient buildings.

Mitigating Curtailment and Carbon Emissions through Load Migration between Data Centers

What a difference a change in administrations makes. Following the November Presidential elections, it was considered a foregone conclusion that the regulation of CO2 and its greenhouse gas (GHG) kin, at least from motor vehicles, was simply a matter of time, in light of the 2007 ruling in Massachusetts et al. vs EPA (549 US 497 [2007]; Front Ecol Environ 5[5]: 279). In that decision, the US Supreme Court found that, “greenhouse gases fit well within the Clean Air Act's [CAA] capacious definition of air pollutant”. The Supreme Court ordered the Environmental Protection Agency (EPA) to determine specifically if emissions of GHGs from new automobiles pose a danger to human health. It is important to remember that the Court did not rule on whether CO2 emissions cause global warming, but on whether scientific uncertainty was a valid reason for the EPA not to regulate a pollutant under the CAA. The Bush Administration sided with the uncertainty argument; the Obama Administration, however, is taking the opposite viewpoint. In November 2008, the EPA Environmental Appeals Board, in In re: Deseret Power Electric Cooperative, reviewed a construction permit for a new waste-coal-fired electrical generation unit in Bonanza, UT. The Board ruled that the EPA had no valid reason for refusing to limit CO2 emissions from new coal-fired power plants. The ruling, practically speaking, suggests that all new and proposed coal plants are required to address their GHG emissions. The most momentous event, however, was held on April 17, when Lisa P Jackson, the new EPA Administrator, signed the Proposed Endangerment and Cause or Contribute Findings for Greenhouse Gases Under Section 202(a) of the Clean Air Act. Jackson then announced the beginning of a 60-day public comment period, prior to a proposed rule-making, based on a scientific analysis and endangerment finding that would seek to regulate six GHGs – CO2, methane, nitrous oxide, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride – that pose a potential threat to public health. The announcement was not accompanied by a draft rule seeking to limit GHG emissions directly; rather, the EPA indicated that the comment period was important to an eventual regulatory decision, and that drafting of proposed standards would proceed simultaneously. Notably, the EPA stated that the increasing atmospheric levels of the six GHGs are “the unambiguous result” of human activities and are responsible for more intense heat waves, storms, and wildfires; increased flooding and droughts; and other “effects on public health and welfare”. The document further states, “The heating effect caused by the human-induced buildup of greenhouse gases in the atmosphere is very likely the cause of most of the observed global warming over the last 50 years”. Under Section 202(a) of the CAA, the EPA must decide (1) if GHGs may reasonably be anticipated to endanger public health or welfare, and (2) whether, in the Administrator's judgment, emissions of an air pollutant from new motor vehicles cause or contribute to GHG pollution. If the EPA finds in the affirmative to both questions, standards must be issued. While this proposal deals with cars and trucks, other GHG emission sources can't be far behind. The Obama Administration would prefer the more favorable political course of having Congress pass legislation that would lead to revisions in the CAA through the enactment of a cap-and-trade program. The EPA, it seems, is essentially taking the position that, if Congress doesn't act, they will. So industry can select the proverbial “door #1” and install best-available control technology in areas where GHGs would be regulated as pollutants, or choose “door #2” and introduce some sort of nationwide method of capping GHGs, and allow market forces to dictate a market for such pollutants. Frank O'Donnell, president of Clean Air Watch, described this impending game of “chicken” as: “If business groups, such as the US Chamber of Commerce, continue to oppose Congressional action, they ought to ask themselves…‘Do I feel lucky?' ” Discussion drafts of legislation have already begun to circulate, including the Waxman-Markey American Clean Energy and Security Act of 2009, a complex bill involving carbon control and elimination. So progress is being made, albeit slowly. Profound environmental issues don't usually lend themselves to humor, but we can all hope that a headline that once appeared in The Onion – “Fall cancelled after 3 billion seasons…a beloved classic comes to an end” – will generate future chuckles rather than appreciation for its prescience. And then there is: “How many global warming skeptics does it take to change a light bulb? None. It's too early to say if the light bulb needs changing.”

National and international agreements aim to limit climate change and thus call for a reduction of greenhouse gas (GHG) emissions to nearly zero. A wide range of technologies promise to reduce the heat demand of buildings and also promote renewable energies. One of these technologies is the use of solid building structures as thermal storage, so called thermally activated building parts or TABS. Thermal simulations of such energy concept for a typical single-family house with 140 m² living space featuring a heat pump, a solar thermal collector and TABS show that the share of solar heat for heat supply can be increased, resulting in a decreased use of the heat pump and thus a lower demand of electric energy. This leads to reduced greenhouse gas emissions and lower operating costs. Furthermore, the simulations show that larger sizes of the TABS and the solar thermal collector lead to lower demand of electric energy. To secure a reduction of greenhouse gas emissions and costs over the whole lifecycle of a building also production and dismantling, disposal and recycling must be considered. A Life Cycle Cost (LCC) Analysis shows that TABS in combination with solar heat reduce LCC, expressed as present values, by app. 34%. The reductions are mainly due to the lower operating costs of the heating system. Increasing the size of south-facing solar collectors leads to asymptotically decreasing costs. For the less favourable orientations to the West and East, the optimum size of the collector is between 30 and 40 m², depending on the orientation and the size of the TABS. A minimum size of the TABS must be available, while additional TABS do not lead to further reductions. Also in an ecologic sense, the use of TABS in combination with solar heat is beneficial. The simulations in this research show that the greenhouse gas (GHG) emissions over the whole lifecycle can be reduced by 27%. Again, the reduction mainly results from the decreased demand of electric energy and only slightly higher GHG emissions from the production of the TABS. Larger collector sizes lead to asymptotically reduced GHG emissions, when south facing. In contrast, orientations to the East and West lead to increased GHG emissions as the size of the collector increases. Integrated systems of heat pumps, solar thermal collectors and TABS could also be considered for multi-family housing and other building types. Simulations of LCC and LCA offer a suited means for assessing economic and ecologic impacts of innovative buildings concepts and should be used on a wider scale, ideally in combination.

BackgroundThe availability of feedstock options is a key to meeting the volumetric requirement of 136.3 billion liters of renewable fuels per year beginning in 2022, as required in the US 2007 Energy Independence and Security Act. Life-cycle greenhouse gas (GHG) emissions of sorghum-based ethanol need to be assessed for sorghum to play a role in meeting that requirement.ResultsMultiple sorghum-based ethanol production pathways show diverse well-to-wheels (WTW) energy use and GHG emissions due to differences in energy use and fertilizer use intensity associated with sorghum growth and differences in the ethanol conversion processes. All sorghum-based ethanol pathways can achieve significant fossil energy savings. Relative to GHG emissions from conventional gasoline, grain sorghum-based ethanol can reduce WTW GHG emissions by 35% or 23%, respectively, when wet or dried distillers grains with solubles (DGS) is the co-product and fossil natural gas (FNG) is consumed as the process fuel. The reduction increased to 56% or 55%, respectively, for wet or dried DGS co-production when renewable natural gas (RNG) from anaerobic digestion of animal waste is used as the process fuel. These results do not include land-use change (LUC) GHG emissions, which we take as negligible. If LUC GHG emissions for grain sorghum ethanol as estimated by the US Environmental Protection Agency (EPA) are included (26 g CO2e/MJ), these reductions when wet DGS is co-produced decrease to 7% or 29% when FNG or RNG is used as the process fuel. Sweet sorghum-based ethanol can reduce GHG emissions by 71% or 72% without or with use of co-produced vinasse as farm fertilizer, respectively, in ethanol plants using only sugar juice to produce ethanol. If both sugar and cellulosic bagasse were used in the future for ethanol production, an ethanol plant with a combined heat and power (CHP) system that supplies all process energy can achieve a GHG emission reduction of 70% or 72%, respectively, without or with vinasse fertigation. Forage sorghum-based ethanol can achieve a 49% WTW GHG emission reduction when ethanol plants meet process energy demands with CHP. In the case of forage sorghum and an integrated sweet sorghum pathway, the use of a portion of feedstock to fuel CHP systems significantly reduces fossil fuel consumption and GHG emissions.ConclusionsThis study provides new insight into life-cycle energy use and GHG emissions of multiple sorghum-based ethanol production pathways in the US. Our results show that adding sorghum feedstocks to the existing options for ethanol production could help in meeting the requirements for volumes of renewable, advanced and cellulosic bioethanol production in the US required by the EPA’s Renewable Fuel Standard program.

Plug-in photovoltaics (PV)/battery power systems attract increasing interest due to their merits in zero fuel consumption and zero local emission. However, current optimization for the plug-in PV/battery power system only considers a single objective of minimizing lifecycle cost, which may result in increased lifecycle greenhouse gas (GHG) emission due to electricity generation from coal in some areas. The paper therefore proposes a bi-objective optimization methodology to find out an optimal trade-off between lifecycle cost and GHG emission. Non-dominated sorting genetic algorithm II is developed to explore the Pareto solution sets. An unmanned patrol boat is considered as a study case. Simulation results show that the optimal design from the bi-objective optimization gains a 12.6% reduction in lifecycle cost and a 53.8% reduction in GHG emission when compared with the conventional power system consisting of diesel engines and generators. Moreover, the optimal design achieves a 46.3% reduction in GHG emission compared with the single-objective one aimed at minimum lifecycle cost, which at the same time increases the lifecycle cost by just 0.6%. Besides, two variables (the number of PV array and the number of battery modules) are found to be the most sensitive to the contradiction between lifecycle cost and GHG emission.

Energy-related activities are a major contributor of greenhouse gas (GHG) emissions. A growing body of knowledge clearly depicts the links between human activities and climate change. Over the last century the burning of fossil fuels such as coal and oil and other human activities has released carbon dioxide (CO2) emissions and other heat-trapping GHG emissions into the atmosphere and thus increased the concentration of atmospheric CO2 emissions. The main human activities that emit CO2 emissions are (1) the combustion of fossil fuels to generate electricity, accounting for about 37% of total U.S. CO2 emissions and 31% of total U.S. GHG emissions in 2013, (2) the combustion of fossil fuels such as gasoline and diesel to transport people and goods, accounting for about 31% of total U.S. CO2 emissions and 26% of total U.S. GHG emissions in 2013, and (3) industrial processes such as the production and consumption of minerals and chemicals, accounting for about 15% of total U.S. CO2 emissions and 12% of total ...

Beef cattle production is an important agricultural activity in Brazil, which influences environmental and resource consumption. This study analyzed greenhouse gas (GHG) emission impacts from 17 farms, representing the Brazil’s productive system and determined possible improvements in the production chain. Methane, nitrous oxide, and carbon dioxide emissions were evaluated using the updated Intergovernmental Panel on Climate Change (IPCC) guidelines for national inventories. The GHG inventory included emissions from animals, feeds, and “cradle-to-farm-gate” operations for animal management. Regression analyses of carbon dioxide equivalent (CO2eq) emissions and productive indices were performed to identify possible GHG emission hotspots. The results varied considerably among the farms. The GHG yield ranged from 8.63 to 50.88 CO2eq kg carcass−1. The productive indices of average daily gain (p < 0.0001), area productivity (p = 0.058), and slaughtering age (p < 0.0001) were positively correlated with GHG yield. However, no correlation was found with the stocking rate (p = 0.21). The production chain could be improved through accurate animal management strategies that reduce the slaughtering age and daily weight gain individually or per area using pasture management and strategic animal supplementation, which could subsequently reduce GHG emissions in beef cattle production.