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

Mitigating Curtailment and Carbon Emissions through Load Migration between Data Centers

Increased use of natural gas has been promoted as a means of decarbonizing the US power sector, because of superior generator efficiency and lower CO2 emissions per unit of electricity than coal. We model the effect of different gas supplies on the US power sector and greenhouse gas (GHG) emissions. Across a range of climate policies, we find that abundant natural gas decreases use of both coal and renewable energy technologies in the future. Without a climate policy, overall electricity use also increases as the gas supply increases. With reduced deployment of lower-carbon renewable energies and increased electricity consumption, the effect of higher gas supplies on GHG emissions is small: cumulative emissions 2013–55 in our high gas supply scenario are 2% less than in our low gas supply scenario, when there are no new climate policies and a methane leakage rate of 1.5% is assumed. Assuming leakage rates of 0 or 3% does not substantially alter this finding. In our results, only climate policies bring about a significant reduction in future CO2 emissions within the US electricity sector. Our results suggest that without strong limits on GHG emissions or policies that explicitly encourage renewable electricity, abundant natural gas may actually slow the process of decarbonization, primarily by delaying deployment of renewable energy technologies.

Anthropogenic greenhouse gases (GHG) emission and related global warming issues have been the focus of international communities for some time. The international communities have reached a consensus to reduce anthropogenic GHG emissions and restrain global warming. The quantitative assessment of anthropogenic GHG emissions is the scientific basis to find out the status of global GHG emission, identify the commitments of each country, and arrange the international efforts of GHG emission reduction. Currently the main assessment indicators for GHG emission include national indicator, per capita indicator, per GDP indicator, and international trade indicator etc. The introduction to the above indicators is put forward and their merits and demerits are analyzed. Based on the GHG emission data from the World Resource Institute (WRI), the US Energy Information Administration (EIA), and the Carbon Dioxide Information Analysis Center (CDIAC), the results of each indictor are calculated for the world, for the eight G8 industrialized countries (USA, UK, Canada, Japan, Germany, France, Italy and Russia), and the five major developing countries including China, Brazil, India, South Africa and Mexico. The paper points out that all these indicators have some limitations. The Indicator of Industrialized Accumulative Emission per Capita (IAEC) is put forward as the equitable indicator to evaluate the industrialized historical accumulative emission per capita of every country. IAEC indicator can reflect the economic achievement of GHG emission enjoyed by the current generations in every country and their commitments. The analysis of IAEC indicates that the historical accumulative emission per capita in industrialized countries such as UK and USA were typically higher than those of the world average and the developing countries. Emission indicator per capita per GDP, consumptive emission indicator and survival emission indicator are also put forward and discussed in the paper.

SUMMARYBiofuels can reduce greenhouse gas (GHG) emissions by replacing fossil fuels. However, the energy yield from agronomic crops varies due to local climate, weather and soil variability. A variation in the yield of raw material used (feedstock) could also cause variability in GHG reductions if biofuels are used. The goal of the present study was to determine the net reduction of GHG emissions if ethanol from wheat produced in different regions of the south-eastern USA is used as an alternative to gasoline from fossil fuel sources. Two scenarios were investigated; the first included ethanol produced from grain only, and the second included ethanol produced from both grain and wheat straw. Winter wheat yield was simulated with the Cropping System Model (CSM)-CERES-Wheat model for climate, soil and crop management representing six counties in the following USA states: Alabama, Florida and Georgia. Ethanol production was determined from the simulated grain and straw yields together with fixed grain and straw yield ethanol ratios. Subsequently, net reductions in GHG emissions were determined by accounting for the emissions from the replaced gasoline, and by animal feed and electricity that were replaced by ethanol processing co-products. Greenhouse gases that were emitted in the ethanol production chain were also taken into account. Across all locations, the reduction in GHG emissions was 187 g CO2-equivalents/km in the grain-only scenario and 208 g CO2-equivalents/km in the grain and straw scenario. The reductions in GHG emissions varied significantly between locations and growing seasons within the two scenarios. Similar approaches could be applied to assess the environmental impact of GHG emissions from other biofuels.

It is estimated that the transport sector contributes to 17-18% of greenhouse gas emissions in Australia. Out of which, 63% of these toxic emissions are originating from the internal combustion engine (ICE) based light vehicles. These poisonous emissions negatively impact on the environment, climate, and health and are responsible for asthma, cancer, bronchitis, and sometimes premature death. Governments and policymakers are setting up policy directives and subsidies to replace the ICE-based vehicles with electric vehicles (EVs). The adoption of EVs will shift the energy demand from the transport sector to the electricity sector. As the electricity sector of some countries (e.g., Australia) is still heavily depending on the fossil-fuel based sources, it is argued that by simply adopting EVs in the transport sector would not make a profound impact on the net reduction in carbon emissions. In this paper, we investigated the impact on net carbon emission reduction due to adoption of EVs using the transport and electricity generation data in Australia. We have investigated four case studies by applying various modelling assumptions based on the type of EV, percentage of ICE-based vehicles converting into EVs, and renewable energy generation projections. Finally, study has made some carbon emission projections for the transport sector till 2050 considering a constant conversion rate for ICE vehicles to EVs, annual uptake of renewable energy into the power grid, and increase in number of EVs. With the present rate of adoption of renewable energy into the power generation portfolio, it would take at least another 8-10 years to make a profound impact on emission reduction in the transport sector, and by 2050 a 75% emission reduction can be achieved compared with the current emission levels in the transport sector.

Switching to electric vehicles can lead to significant reductions of PM2.5 and NO2 across China

Abstract. California's goal to reduce greenhouse gas (GHG) emissions to a level that is 80 % below 1990 levels by the year 2050 will require adoption of low-carbon energy sources across all economic sectors. In addition to reducing GHG emissions, shifting to fuels with lower carbon intensity will change concentrations of short-lived conventional air pollutants, including airborne particles with a diameter of less than 2.5 µm (PM2.5) and ozone (O3). Here we evaluate how business-as-usual (BAU) air pollution and public health in California will be transformed in the year 2050 through the adoption of low-carbon technologies, expanded electrification, and modified activity patterns within a low-carbon energy scenario (GHG-Step). Both the BAU and GHG-Step statewide emission scenarios were constructed using the energy–economic optimization model, CA-TIMES, that calculates the multi-sector energy portfolio that meets projected energy supply and demand at the lowest cost, while also satisfying scenario-specific GHG emissions constraints. Corresponding criteria pollutant emissions for each scenario were then spatially allocated at 4 km resolution to support air quality analysis in different regions of the state. Meteorological inputs for the year 2054 were generated under a Representative Concentration Pathway (RCP) 8.5 future climate. Annual-average PM2.5 and O3 concentrations were predicted using the modified emissions and meteorology inputs with a regional chemical transport model. In the final phase of the analysis, mortality (total deaths) and mortality rate (deaths per 100 000) were calculated using established exposure-response relationships from air pollution epidemiology combined with simulated annual-average PM2.5 and O3 exposure. Net emissions reductions across all sectors are −36 % for PM0.1 mass, −3.6 % for PM2.5 mass, −10.6 % for PM2.5 elemental carbon, −13.3 % for PM2.5 organic carbon, −13.7 % for NOx, and −27.5 % for NH3. Predicted deaths associated with air pollution in 2050 dropped by 24–26 % in California (1537–2758 avoided deaths yr−1) in the climate-friendly 2050 GHG-Step scenario, which is equivalent to a 54–56 % reduction in the air pollution mortality rate (deaths per 100 000) relative to 2010 levels. These avoided deaths have an estimated value of USD 11.4–20.4 billion yr−1 based on the present-day value of a statistical life (VSL) equal to USD 7.6 million. The costs for reducing California GHG emissions 80 % below 1990 levels by the year 2050 depend strongly on numerous external factors such as the global price of oil. Best estimates suggest that meeting an intermediate target (40 % reduction in GHG emissions by the year 2030) using a non-optimized scenario would reduce personal income by USD 4.95 billion yr−1 (−0.15 %) and lower overall state gross domestic product by USD 16.1 billion yr−1 (−0.45 %). The public health benefits described here are comparable to these cost estimates, making a compelling argument for the adoption of low-carbon energy in California, with implications for other regions in the United States and across the world.

In recent years, there has been a proliferation of new federal investments and policy support for "carbon management" technologies, such as carbon capture and storage (CCS), as a strategy to mitigate the United States' greenhouse gas emissions (GHGs). The equity implications of deploying these technologies-particularly their impacts on low-income communities and communities of color, or environmental justice (EJ) communities-have been understudied. A prominent example of this is seen in the US power sector, where CCS has been proposed as a means to mitigate the carbon dioxide emissions of fossil fuel-fired power plants, one of the major sources of GHGs in the country. EJ community leaders alongside some environmental organizations and researchers have voiced deep concerns about how CCS may exacerbate environmental injustice, given that it is itself input-intensive and can prolong the life of polluting fossil fuel infrastructure, which is disproportionately sited in low-income communities and communities of color. To begin to fill the gap in analyses of the equity implications of carbon management, we conducted a spatial analysis of CCS projects proposed for the power sector and their co-location with EJ communities. Compiling a proposed project list from four CCS databases, we found that 33 of the 35 projects were located in EJ communities, and that additionally, 423 of the 497 (or 85%) EJ census block groups located within three miles of at least one proposed project currently face heightened environmental stress. These results illustrate both the feasibility and the necessity of analyzing the co-location of proposed CCS buildout in EJ communities, and add to the nascent body of literature evaluating the impacts of carbon management technologies such as CCS on these communities.

Consequential life cycle assessment of automotive material substitution: Replacing steel with aluminum in production of north American vehicles

Spatiotemporally explicit pathway and material-energy-emission nexus of offshore wind energy development in China up to the year 2060

In Malaysia, the greenhouse gases (GHGs) emissions reduction via composting of source-separated organic waste (SOW) in municipal solid waste (MSW) has not been assessed. Assessment of GHG emissions reduction via composting of SOW is important as environmental impacts from waste management are waste-specific and local-specific. The study presents the case study for potential carbon reduction via composting of SOW in University of Malaya (UM). In this study, a series of calculations were used to evaluate the GHG emission of different SOW management scenarios. The calculations based on IPCC calculation methods (AM0025) include GHGs emissions from landfilling, fuel consumption in transportation and SOW composting activity. The methods were applied to assess the GHG emissions from five alternative SOW management scenarios in UM. From the baseline scenario (S0), a total of 1,636.18 tCO(2e) was generated. In conjunction with target of 22 recycling rate, as shown in S1, 14 reduction in potential GHG emission can be achieved. The carbon reduction can be further enhanced by increasing the SOW composting capacity. The net GHG emission for S1, S2, S3 and S4 were 1,399.52, 1,161.29, 857.70 and 1,060.48 tCO(2e), respectively. In general, waste diversion for composting proved a significant net GHG emission reduction as shown in S3 (47), S4 (35) and S2 (29). Despite the emission due to direct on-site activity, the significant reduction in methane generation at landfill has reduced the net GHG emission. The emission source of each scenario was studied and analysed.

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 ...

Previsualizing a Post-Combustion World “For when in all other places the Aer is most Serene and Pure, it is here Ecclipsed with such a Cloud of Sulphure, as the Sun it self, which gives day to all the World besides, is hardly able to penetrate and impart it here; and the weary Traveller, at many Miles distance, sooner smells, then sees the City to which he repairs.” — Evelyn (1661) “Using the commons as a cesspool does not harm the general public under frontier conditions, because there is no public; the same behavior in a metropolis is unbearable. — Hardin (1968) “There is nothing worse than a sharp image of a fuzzy concept.” — Ansel Adams The taming of fire and its application for beneficial purposes is a great achievement of humankind. And yet, fire is not fully tamed. Carbon dioxide from the burning of fossil fuels is altering Earth’s climate. Emissions from power plants produce regional haze. Motor vehicle emissions foul urban air. Cooking with solid fuels pollutes the households of billions. Perhaps it is time for humankind to start planning to leave behind deliberate combustion. Ansel Adams wrote about visualization, stressing the photographer’s need to imagine the captured and printed image before attempting an exposure. Minor White named a part of this process previsualization: imagining the outcome while studying the subject. For the purposes of this editorial, I use this term to acknowledge the difficulty to fully imagine a modern, future world that doesn’t rely upon combustion. Nevertheless, I believe that the effort to previsualize can inspire and guide efforts that promise beneficent outcomes. Climate change concerns provide a strong impetus for divesting ourselves from our heavy dependence on combustion. Although lacking as yet is a sufficiently strong international agreement to effectively counteract anthropogenic climate change, some people and some governments are taking action. The case of California illustrates some important points. In 2005, then Governor Arnold Schwarzenegger signed an executive order calling for strong future reduction in greenhouse gas emissions. The longer-term goal targets a reduction by 2050 to 80 percent below the state’s 1990 emission levels. A year 2015 executive order from current Governor Jerry Brown reaffirmed this goal. Allowing for expected population growth, the necessary per capita emissions reduction would be roughly 90 percent, to a level of about 1 kg of carbon equivalent per day per California resident. That per capita average greenhouse emission rate, if achieved worldwide during the second half of the 21 st century, would help maintain the atmospheric CO 2 levels below an upper bound of ~ 450-550 ppm (based on predictions for the 21 st century for ICPP scenarios RCP2.6 and RCP4.5). Those levels would not suffice to prevent some climate change, but these outcomes would be far better for the environment than unbridled continuation of business-as-usual, for which a year 2100 ambient CO 2 level is predicted to range from ~ 650 ppm to above 900 ppm (based on predictions for ICPP scenarios RCP6.0 and RCP8.5). According to data from the US Energy Information Administration, the year 2012 global-average per-capita carbon dioxide emission rate from energy use corresponds to almost 3.5 kg of carbon

The power sector is responsible for approximately one-half of the United States’ annual water withdrawals and approximately 3% of its annual water consumption. The majority of this water is devoted to cooling thermoelectric power plants by means of once-through or recirculating cooled systems. Despite the large water requirements of the power sector, water conservation strategies are typically concentrated in the urban and agricultural sectors. Although national agencies such as the United States Geological Survey and the Energy Information Administration do publish data regarding the water use requirements of power plants, these data are often incomplete, inaccurate, and are published infrequently. Consequently, data resolving the temporal variability of water use by the power sector are largely non-existent, making conservation strategies difficult to construct. This analysis utilizes a unit commitment and dispatch (UCD however, water consumption data (i.e., the subset of water withdrawals that is evaporated) has not been reported since 1995. The US Energy Information Administration (EIA) reports cooling water consumption and withdrawal data annually for thermoelectric power generators through its EIA-860 form based on flow rate, but these data are often missing or erroneous, and lack temporal fidelity. There are two types of cooling technologies that are used by the majority of EGUs in the US. Once-through (OT) cooling technologies withdraw large amounts of water from a river or water reservoir, use the water once to cool the hot steam exiting the turbine during power production, and then discharge the warm cooling water back to the original water reservoir. During this process, very little water is lost to evaporation since the water is only used once for cooling. Recirculating cooling systems, by contrast withdraw smaller volumes of water by recycling the water within cooling towers. Since water is cycled multiple times, most of the water that is withdrawn from the original water source is ultimately lost to evaporation, that is, it is consumed. Unlike OT cooling systems, RC cooling systems do not discharge large quantities of water back into the native water reservoirs. Because of these differences in operational water requirements and varying impacts on the cooling source water reservoir, there are tradeoffs between these two technologies. OT cooling systems withdraw large volumes of water, but consume very little, which is therefore good for water availability compared to high water consumption technologies. RC systems require smaller volumes of water, but very little (if any) of the water that is extracted from a reservoir is ultimately returned to the water shed after generation. RC systems, therefore, can be less prone to generation disruptions in areas where water is constrained, but have larger evaporative losses than OT systems. The distribution of OT and RC cooled EGUs varies regionally. Thermoelectric power generators in the western US use a larger fraction of RC cooling systems since the region is generally drier than the comparatively water-rich Eastern US. Eighty percent of the units of electricity generated in the eight most Western US (including Oregon, Washington, Idaho, Montana, Arizona, Nevada, New Mexico, and California) was produced in RC cooled facilities in 2005. (The majority of electricity generated in OT cooled facilities was produced along the coast and using saline cooling water.) By contrast, 54% and 46% of the electricity generated in the remainder of the Eastern US states is derived from OT and RC cooled facilities, respectively. This trend reflects the fact that the Eastern US generally has more water available for withdrawal-intensive cooling facilities. (Table 1 details 2005 water use for thermoelectric electricity production in Eastern and Western US states.) The Western Electricity Coordinating Council (WECC) is the regional entity within the North American Electric Reliability Corporation that coordinates and promotes reliable bulk power transmission across the western United States (i.e. Washington, Oregon, California, Idaho, Nevada, Utah, Arizona, Colorado, Wyoming, as well as portions of Montana, South Dakota, New Mexico, and Texas), Baja California, Mexico, and western Canada. The WECC power grid provides a valuable case study for this research because it is the largest regional power coordination entity in North America, serving approximately 82 million people across 1.8 million square miles and includes the majority of North American regions that have experienced “extreme” or “exceptional” drought in the past decade.

The coal epidemic