A systems approach to quantify greenhouse gas fluxes from pastoral dairy production as affected by management regime

The dairy Carbon Offset Scenario Tool (COST) was developed to explore the influence of various abatement strategies on greenhouse gas (GHG) emissions for Australian dairy farms. COST is a static spreadsheet-based tool that uses Australian GHG inventory methodologies, algorithms and emission factors to estimate carbon dioxide, methane and nitrous oxide emissions of a dairy farm system. One of the key differences between COST and other inventory-based dairy GHG emissions calculators is the ability to explore the effect of reducing total farm emissions on farm income, assuming the strategy was compliant with Kyoto rules for carbon offsets. COST provides ten abatement strategies across the four broad theme areas of diet manipulation, herd and breeding management, feedbase management and waste management. Each abatement strategy contains four sections; two sections for data entry (baseline farm data specific to the strategy explored and strategy-specific variables) and two sections for results (milk production results and GHG/economic-related results). Key sensitive variables for each strategy, identified from prior research, and prices for milk production and carbon offsets are adjusted through up/down buttons, which allows users to quickly explore the impact of these variables on farm emissions and profitability. For example, if the cost to implement an abatement strategy is doubled, what carbon offset income would be required to negate this additional cost? Results are presented as changes in carbon offset income, strategy implementation cost, additional milk production income and net farm income on a per annum and on a per GHG emissions intensity of milk production basis. COST currently contains a comprehensive range of strategies for GHG abatement, although some strategies are still in development. As new technologies or farm management practices leading to a reduction in GHG emission become available, these too will be incorporated into COST. To date, two dairy-specific abatement methodologies have been legislated as part of Australia’s commitment to reducing on-farm GHG emissions through it’s the carbon offset scheme, the Carbon Farming Initiative (CFI) and are incorporated into COST. These are the ‘Destruction of methane generated from dairy manure in covered anaerobic ponds’ and the ‘Methodology for reducing greenhouse gas emissions in milking cows through feeding dietary additives’. As an example, we explored the mitigation option Replace supplements with a source of dietary fats (reflecting the second above-mentioned CFI legislated abatement strategy) as feeding a diet higher in dietary fats has been shown to reduce enteric methane emissions per unit of feed intake. A 400 milking herd was fed a baseline diet of 2.6% dietary fat. By replacing grain with hominy meal, at a rate of 5.0 kg dry matter/ cow per day for 90 days during the 3 summer months, the summer diet fat concentration was increased to 6.4%. Enteric methane emissions were reduced by 40 tonnes of carbon dioxide equivalents (t CO 2 e) per annum for the farm. Waste methane and nitrous oxide emissions were also reduced by 0.5 and 1.6 t CO 2 e/annum, respectively. However, as reductions from these two sources of GHG emissions do not qualify for payment with this CFI methodology, their reduction could not be included as an offset income. At a carbon price of $20/ t CO 2 e, the reduction in enteric methane emissions was valued at $800/farm. The implementation cost of replacing grain with hominy was valued at $18,000/farm due to the hominy meal costing an additional $100/t dry matter compared to the grain. However, the additional milk production achieved due to the higher energy concentration of the diet resulted in an additional 70,200 litres and based on a summer milk price of $0.38/ litre, this equated to an additional income from milk valued at $26,676/farm. The overall result was a net increase in farm profit of $9,476/farm when paid on a reduction in total GHG emissions. COST can quickly allow users to ascertain the level of GHG emission reduction possible with various mitigation options and explore the sensitivity of key variables on GHG emissions and farm profitability.

Mitigating Curtailment and Carbon Emissions through Load Migration between Data Centers

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

Well-to-wheel greenhouse gas emissions of electric versus combustion vehicles from 2018 to 2030 in the US

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 ...

Retrospective dynamic life cycle assessment of residential heating and cooling systems in four locations in the United States

The decarbonisation of the construction sector is critical to meet national and international climate goals. Literature gives many examples of measures for the reduction of greenhouse gas (GHG) emissions from buildings. However, few studies investigate the trade-offs between potentially conflicting GHG emission reduction measures or the affordability of these measures. Ydalir is a Zero Emission Neighbourhood (ZEN) pilot area in the Norwegian research centre for Zero Emission Neighbourhoods in smart cities. One of the major challenges Ydalir faces is how to reduce GHG emissions from the neighbourhood towards a net zero emission building (nZEB). Additional challenges include retaining social, environmental, and economical sustainability for both the project developer and building owners and avoid suboptimal solutions. This paper investigates the trade-offs between energy efficiency and material use for two scenarios. The scenarios are a Norwegian building code scenario and a passive house scenario. The analysis ascertains total energy demand, whole life cycle GHG emissions, and cost assessment for two housing units within Ydalir Torg. The results show lower total GHG emissions and lower GHG emissions from operational energy use in the passive house scenario, and an increase in GHG emissions from the production phase due to thicker levels of insulation. The cost assessment shows increased investment costs for the project developer in the passive house scenario, despite lower operational costs for the building owner. Total GHG emission payback times for the passive house scenario are at 18 - 19 years. Cost payback time varies between 10 - 37 years. This paper is useful for practitioners that wish to balance GHG emission reduction requirements between operational energy use, material use and affordability.

Greenhouse gas emissions from pastoral based dairying systems: The effect of uncertainty and management change under two contrasting production systems

Greenhouse gas (GHG) emissions reduction in the electricity sector: Implications of increasing renewable energy penetration in Ghana's electricity generation mix

Whole-farm systems modelling of greenhouse gas emissions from pastoral suckler beef cow production systems

The Earth's surface temperature is steadily increasing due to the accumulation of greenhouse gases, a phenomenon known as global warming. Human activities are the root cause of this significant global issue. Reducing greenhouse gas (GHG) emissions is one of the most critical actions in climate change mitigation. Organizations can engage in activities that promote change and reduce greenhouse gases by acknowledging the significance of addressing climate change. By reducing GHG emissions and promoting the use of renewable energy, organizations can begin to address environmental issues. Therefore, the purpose of this investigation is to assess the reduction of GHG emissions in an educational institution by substituting electricity consumption from the electrical grid with renewable energy in the form of a solar PV rooftop on-grid system. The School of Renewable Energy's GHG emissions were assessed, covering three scopes of GHG emissions activities: direct emissions, indirect emissions, and other indirect emissions. The organization's activity data were collected over a 12-month period. Without installing a solar panel system, the organization reported total GHG emissions of 310.40 tCO2e, relying solely on imported electricity for internal use. The highest GHG emissions were from Scope 2, amounting to 239.38 tCO2e, primarily due to electricity importation. Scope 3 had the second highest GHG emissions, totaling 65.76 tCO2e, resulting from employee commuting and the use of purchased goods such as paper and tap water. Scope 1 had the lowest GHG emissions at 5.26 tCO2e, produced by the combustion of diesel and gasoline in both stationary and mobile sources, as well as CH4 emissions from the septic tank. The percentage of GHG emissions from Scope 2 activities was 77.12%, which was considered to have a significant environmental impact and contribute to global warming. This was because 478,851 kWh of electricity were imported. The installation of on-grid solar cells for power generation reduced imported electricity to 113,120 kWh. Consequently, GHG emissions from Scope 2 decreased to 56.55 tCO2e, leading to an overall reduction in the organization's GHG emissions to 127.57 tCO2e. The organization's GHG emissions decreased by 182.83 tCO2e as a result of using alternative energy to generate electricity. This assessment can serve as a database for educational institutions and prepare the government to report greenhouse gas emissions. Furthermore, it can serve as carbon credits for trading and exchanging carbon with other organizations to offset GHG emissions from various activities. In addition, it endorses the government's goal of achieving carbon neutrality and net zero emissions in the future.

Devising policies for a low carbon city requires a careful understanding of the characteristics of urban residential lifestyle and consumption. The production-based accounting approach based on top-down statistical data has a limited ability to reflect the total greenhouse gas (GHG) emissions from residential consumption. In this paper, we present a survey-based GHG emissions accounting methodology for urban residential consumption, and apply it in Xiamen City, a rapidly urbanizing coastal city in southeast China. Based on this, the main influencing factors determining residential GHG emissions at the household and community scale are identified, and the typical profiles of low, medium and high GHG emission households and communities are identified. Up to 70% of household GHG emissions are from regional and national activities that support household consumption including the supply of energy and building materials, while 17% are from urban level basic services and supplies such as sewage treatment and solid waste management, and only 13% are direct emissions from household consumption. Housing area and household size are the two main factors determining GHG emissions from residential consumption at the household scale, while average housing area and building height were the main factors at the community scale. Our results show a large disparity in GHG emissions profiles among different households, with high GHG emissions households emitting about five times more than low GHG emissions households. Emissions from high GHG emissions communities are about twice as high as from low GHG emissions communities. Our findings can contribute to better tailored and targeted policies aimed at reducing household GHG emissions, and developing low GHG emissions residential communities in China.

Healthy diets with reduced environmental impact? – The greenhouse gas emissions of various diets adhering to the Dutch food based dietary guidelines

The contribution of agriculture to the emission of the main greenhouse gases, CO2, N2O, and CH4, is estimated to be between 25 and more than 50% of the total emissions worldwide. These data indicate that in developed, industrialized countries, severe policies might be successful in strongly reducing greenhouse gas emissions by focusing on agriculture. However, despite its central importance, agriculture is not at the center of political debate or meaningful emission-reducing policies. In this scientific review, current knowledge of the factors affecting the emission of greenhouse gases, including carbon dioxide, nitrous oxide, and methane, from agriculture is critically discussed. The pathways through which the reduction in greenhouse gas emissions from agriculture can be achieved are evaluated. For this purpose, we list the main factors contributing to the emission of greenhouse gases from agriculture and evaluate the roles of agricultural intensification, industrialization, and organic farming in greenhouse gas emissions. If the present trajectory of agricultural development continues, industrialized, intensive conventional agriculture will become an increasing source of greenhouse gas emissions worldwide. Also, the increasing quantitative relevance of energy plants in agriculture will contribute to increasing greenhouse gas emissions. Organic agriculture may offer an alternative means to reduce greenhouse gas emissions by applying the following central boundary conditions: a. the omission of mineral nitrogen fertilizers produced by the Haber–Bosch process, b. the combination of crop and livestock production, and c. the application of nutrient recycling at a regional level. This kind of organic agriculture may combine relatively high and sustainable crop yields with low emissions of greenhouse gases. Industrialized agriculture, whether in its conventional or even its industrialized organic form, is an important source of greenhouse gases with increasing emissions worldwide. Under conditions of agricultural industrialization, industrialized organic agriculture will also contribute to increasing greenhouse gas emissions. At present, there are no political attempts in the countries of the industrialized Western hemisphere to address agriculture-related contributions to greenhouse gas emissions.

For all its cachet, you might think that hybrid drivetrain technology is inherently green. But only 13 of 34 hybrid vehicles assessed achieve better than a 25% reduction in greenhouse gas (GHG) emissions, and just 3 exceed a 40% reduction, according to an evaluation by the Union of Concerned Scientists (UCS).1 Moreover, reductions in GHG emissions do not necessarily correlate with reductions in other toxic emissions. Like any engine output–improving technology, hybrid technology can boost both fuel efficiency and power—but the more you boost one, the less you can boost the other. That dichotomy spurred the UCS to develop its “hybrid scorecard,” which rates each hybrid according to how well it lives up to its promise of reducing air pollution.2 All the vehicles were from model year 2011 except for one, the 2012 Infiniti M Hybrid. First the UCS scored each hybrid on how much it reduced its GHG emissions relative to its conventional counterpart, on a scale of zero (least reduction) to 10 (greatest reduction). These scores reflect the percentage in fuel efficiency gain. For example, the Toyota Prius gets 50 mpg3 compared with 28 mpg for the comparable Toyota Matrix. This represents a 44.0% reduction in GHG emissions, earning the Prius a GHG score of 9.4. At the bottom of the scale, the 21-mpg hybrid VW Touareg reduces GHG emissions only 10% over the 19-mpg conventional Toureg, for a score of 0.0. With a 46% improvement, the luxury Lincoln MKZ Hybrid had the greatest reduction over its conventional counterpart. The UCS also scored hybrids for absolute emissions (rather than relative to the conventional model) of air pollutants including particulate matter, carbon monoxide, hydrocarbons, and nitrogen oxides. These scores, on a scale of zero (dirtiest) to 10 (cleanest), are based on California certifications for tailpipe emissions. As the scorecard showed, a vehicle that emits less heat-trapping gases may not necessarily emit less of other air pollutants. For example, the Mercedes Benz S400 Hybrid scored 9 on air pollution reduction, alongside the Prius and the Lincoln MKZ, but only 1.3 on GHG emissions. HYBRID SCORECARD: Top 10 Nonluxury Hybrids by Total Environmental Improvement Score “Hybrid technology doesn’t add additional challenges [to reducing exhaust pollutants] that can’t be addressed through design of the vehicle’s emission controls,” says Don Anair, senior vehicles analyst at the UCS. “Numerous manufacturers of hybrids are meeting the lowest emissions levels. Hybrid manufacturers who aren’t delivering the lowest smog-forming emissions have chosen not to do so.” Each vehicle’s air pollution and GHG scores were averaged into a total “environmental improvement score,” again with the MKZ and the Prius leading the pack, and the Touareg scraping bottom. The UCS also scored “hybrid value” (the cost of reducing GHG emissions in dollars per percent reduction) and “forced features” (options you must buy with the hybrid whether you want them or not). HYBRID SCORECARD: Top 10 Luxury Hybrids by Total Environmental Improvement Score Luke Tonachel, vehicles analyst with the Natural Resources Defense Council, compliments the scorecard for illustrating that hybrid technology is not automatically green. He says, “We should improve the efficiency of all vehicles, and [hybrid technology] is just one technology that can get us there if applied with that goal in mind.” Nonetheless, Jamie Kitman, the New York bureau chief for Automobile Magazine, questions the wisdom of emphasizing percentage improvement in gas mileage rather than absolute miles per gallon. At 21 mpg, the hybrid Cadillac Escalade 4WD represents a 29% improvement over the 15-mpg conventional model, saving nearly 2 gallons per 100 miles. But the hybrid Escalade is still a gas guzzler, and Kitman says he wishes people would see through the marketing that encourages them to buy SUVs and “crossovers” rather than ordinary cars, which are more efficient than either. Says Anair, “The scorecard shows that automakers can pair hybrid technology with advanced emission controls to help tackle climate change while reducing the health impacts from breathing polluted air.” However, he adds, alluding to the stark variation in how much hybrid technology boosted fuel efficiency, “Not all automakers are delivering on the full promise of this technology.”