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Abstract: The atmospheric levels of carbon dioxide (CO2) have been due largely to the burning of fossil fuels, deforestation, cultivation of the grasslands, drainage of the land, and land use changes. This has led to increase in greenhouse gases, created concerns about the potential for long-term climate change and interest in developing methods to sequester some of this atmospheric carbon. In agricultural land areas no-tillage (NT) systems have been proposed, to replace moldboard plow and chisel systems as a way to sequester soil organic carbon (SOC). Numerous estimates have been published of soil organic carbon (SOC) sequestration total and rates as a result of a switch to NT systems. Other researchers have proposed the use of cover crops, synthetic fertilizers, organic fertilizer, manure, liming, agricultural systems and management, agroforestry, forages, compost, crop rotations, and reduced row crop use as ways to sequester SOC. For SOC sequestration to occur as a result of a treatment applied to a land unit, all of the SOC sequestered must have come from atmosphere and be transferred into the soil humus through the unit plants, plant residues and other organic solids. The amount of SOC present in the soil humus at the end of the study has to be greater than the pre-treatment SOC levels in the same land unit and there needs to be a net depletion of atmospheric CO2 as a result. The objectives of this paper are to: (1) determine long-term study SOC levels and trends in agricultural lands, (2) application of the SOC sequestration concept to a specific site, (3) identify appropriate experimental designs for plot area use in determining SOC sequestration, (4) develop a procedure, such as pre-treatment measurements of SOC levels in the plots before treatments are applied, to verify SOC sequestration at a site (5) equivalent soil mass sampling method, (6) compare laboratory methods for quantifying SOC content, and (7) account for the loading of C rich amendments. To unequivocally demonstrate SOC sequestration at a specific site has occurred, a temporal increase must be documented relative to pre-treatment SOC level and linked to a net depletion of atmospheric CO2. [Copyright &y& Elsevier]

The benefits of biomass as an alternative fossil fuel can be realized mainly through biomass consumption. This paper examines the growth rate and spatial patterns of biomass consumption in the United States (hereafter US) during the period 2000–2012, using the SLOPE index, Moran's I and local Moran's I. Results indicate that US States show either slow growth or slow decline in biomass consumption during the period 2000–2012. The number of States that have slow growth in biomass consumption is slightly larger than the number of States showing slow decline. The pattern of growth rate of biomass consumption revealed by the SLOPE index and the observed pattern of the temporal variation of biomass consumption ensures that the SLOPE index can catch the growth rate of biomass consumption. This pattern does not align with the increased annual investment in biomass, indicating that the investment in biomass does not flow down to the biomass industry effectively. The pattern of growth rate of biomass consumption will provide additional evidence for the debates about the effectiveness of State renewable energy policy, and demonstrates an urgent need for appropriate State renewable energy policies. There is a High-High spatial cluster around the Southeast of the US and a Low-Low spatial cluster in the Middle of the US in 2000, 2004, 2008 and 2012. The regional spatial cluster in biomass consumption has somewhat relationship with the growth rate of biomass consumption, which can help the understanding of the growth rate of biomass consumption. • The SLOPE index is used to investigate the growth rate of biomass consumption. • The pattern of growth rate does not align with the increased annual investment. • There is an urgent need for appropriate State renewable energy policies. • There are regional clusters in biomass consumption in 2000, 2004, 2008 and 2012. • The regional spatial cluster has somewhat relationship with the growth rate. [ABSTRACT FROM AUTHOR]

In this paper, a hybrid renewable power plant with a storage system is designed. The benefits of sizing and energy management are assessed for a commercial building under eight different climatic conditions in the United States. In the considered system, photovoltaic panels are coupled to a unitized regenerative solid oxide fuel cell. The use of biogas to feed unitized regenerative solid oxide fuel cell is investigated, employing a detailed electrochemical model of electrolyzer and fuel cell modes. A battery pack is included in the plant as a secondary storage system, together with a diesel engine operating in backup mode. Four scenarios where biogas amount is varied together with the initial state of charge of the battery were evaluated. Results demonstrate that the power plant can operate with 100 % renewable procurement if the digester produces from 6000 to 9500 stdm3/y and the battery is completely charged at the beginning of the year. By reducing the biogas availability or starting with a low state of charge, the use of the diesel generator is inevitable. The study confirms that the proposed hybrid renewable power plant is technically feasible and can be considered a reliable and clean energy source in other areas and buildings. • Fully renewable power plant optimization/sizing for commercial buildings. • Influence of U.S. climate zones on power plant operations. • Definition of a control strategy for fossil fuel usage minimization. [ABSTRACT FROM AUTHOR]

The aim of this paper is to relate the shale oil revolution in the United States with WTI oil price behavior. Since the development of the combination of horizontal drilling techniques together with hydraulic fracturing in the 1970s, known as shale oil, oil markets have undergone a significant transformation with the unexpectedly strong rise in the United States production affecting oil prices. The goal of this paper is two-fold: first, we analyze the relationship of total United States crude oil production and WTI crude oil prices by studying its performance in the time-frequency domain applying wavelet tools for its resolution. Using wavelet methodologies, we observe a shift to higher frequencies of the wavelet coherency for the time period 2003–2009 and lower frequencies for the period 2009–2014. The results also indicate that during the period 2003–2009 the U.S. oil production and WTI oil prices time series are in phase; they move together, with total United States oil production leading. During the period 2009–2014 oil production and WTI oil prices time series are out of phase (negatively correlated), suggesting that oil production increases precede a decrease in WTI oil prices. In the second part of the paper and to give greater credibility to the results obtained through the wavelet transform, we analyze the behavior of WTI crude oil before and after the shale oil boom in the United States employing methodologies based on long run dependence. The results indicate that mean reversion takes place only for the data corresponding to the first subsample, ending at 2003. For the second subsample, as well as for the whole sample, lack of mean reversion is detected with orders of integration equal to or higher than 1 in all cases. [ABSTRACT FROM AUTHOR]

• The oil price-inflation pass-through is analyzed using a wavelet coherency analysis. • The oil price-inflation pass-through has decreased during the analyzed period. • The oil price-inflation relationship varies across frequencies. This paper analyzes the oil price-inflation pass-through by studying the relationship between oil prices and U.S. Consumer Price Index (CPI) over the period January 1871–June 2018, at different frequencies, using a wavelet coherency analysis. In this long period of time characterized by significant structural changes, which have changed the role of fossil fuel prices (specially, crude oil) relative to renewable and alternative fuels, our main results suggest that the relationship between oil prices and CPI has changed over the analyzed time period, implying a decrease in the oil price- inflation pass-through over time. Furthermore, this relationship also varies across frequencies, suggesting that the evidence of oil price-inflation pass-through with oil prices leading CPI is weaker in the short-run. [ABSTRACT FROM AUTHOR]

Offshore wind is one of the most fascinating industries in the renewable energy sector and it is experiencing a remarkable growth. Offshore wind energy generation offers an opportunity in the race to decrease the dependence on fossil fuels, reduce green house emissions, increase energy security and create employment opportunities. UK has proven success in offshore wind and has been enjoying the economic benefits of offshore wind since over a decade. Offshore wind energy is an emergent renewable energy industry in the United States. The United States is coping up with the challenges and heading up fast to catch up with the industry. India is still in its infancy stage where the policy frameworks are framed by MNRE government and getting ready with the tools to enter into the offshore market. This paper researches the current situation and trend of offshore wind industries in UK and US, from aspects of policy, grid connections, operation and maintenance and cost reduction and analyses the proper direction and pathways of the industry to India. Therefore this paper highlights the scenario as to how these three countries UK, USA and India, respectively, are enabling offshore wind, to make a vital and sizeable contribution to the low carbon economy. [ABSTRACT FROM AUTHOR]

Abstract: This article summarizes the threats that wind farms pose to birds before surveying the recent literature on avian mortality and summarizing common methodological problems with such studies. Based on operating performance in the United States and Europe, the paper then offers a preliminary calculation of the number of birds killed per kilowatt-hour kWh generated for wind electricity, fossil fuel, and nuclear power systems. The study estimates that wind farms and nuclear power stations are responsible each for between 0.3 and 0.4 fatalities per gigawatt-hour (GWh) of electricity while fossil fueled power stations are responsible for about 5.2 fatalities per GWh. Within the uncertainties of the data used, the estimate means that wind farms killed approximately 20,000 birds in the United States in 2009 but nuclear plants killed about 330,000 and fossil fueled power plants more than 14 million. The paper concludes that further study is needed, but also that fossil fueled power stations appear to pose a much greater threat to birds and avian wildlife than wind farms and nuclear power plants. [Copyright &y& Elsevier]

Following four years of relative stability at around $106 per barrel (bbl), oil prices have declined sharply since June 2014 and are expected to remain low for a considerable period of time. There are multiple factors which are being considered behind the plunge in the price of oil since June 2014. Most observers have conjectured that domestic oil boom in the United States and Iraq is the major cause for the falling oil prices. Some have suggested that a major shock to oil price expectations occurred after the November 2014 meeting of OPEC, when they did not cut production despite the steady increase in non-OPEC oil production. In this paper, first we analyzed the effect of various factors on the oil prices and then we studied impacts of the falling oil prices on non-hydro renewable energy. We compare the recent decline in oil prices with previous episodes up to 1996. We show that the demand and supply formula cannot be implemented to the current oil plunge. The study shows that so far the recent plunge in oil prices has produced no major impact on renewable energy sector. We found that renewable energies, such as solar and wind, are increasingly becoming cost competitive with fossil fuel energy. However the oil price crash could hurt the short-term outlook for certain specific clean energy technologies such as bio-fuel and electric vehicles that do compete with oil-based transportation. While long term low oil prices may threaten renewable energies, climate policies have the potential to act as a counterweight, encouraging long-term, low carbon, investment. [ABSTRACT FROM AUTHOR]

Biomass is low-carbon energy and has tremendous potential as an alternative to fossil fuels. However, the significant role of biomass in future low-carbon energy portfolio depends heavily on its consumption. The paper presents a first attempt to examine the spatial-temporal patterns of biomass consumption in the United States (US), using a novel method-spatial Seemingly Unrelated Regression (SUR) model, in order to strengthen the link between energy planning and spatial planning. In order to obtain the robust parameters of spatial SUR models and estimate the parameters efficiently, an iterative maximum likelihood method, which takes full advantage of the stationary characteristic of maximum likelihood estimation, has been developed. The robust parameters of models can help draw a proper inference for biomass consumption. Then the spatial-temporal patterns of biomass consumption in the US at the state level are investigated using the spatial SUR models with the estimation method developed and data covering the period of 2000–2012. Results show that there are spatial dependences among biomass consumption. The presence of spatial dependence in biomass consumption has informative implications for making sustainable biomass polices. It suggests new efforts to adding a cross-state dimension to state-level energy policy and coordinating some elements of energy policy across states are still needed. In addition, results consistent with classic economic theory further proves the correctness of applying the spatial SUR models to investigate the spatial-temporal patterns of biomass consumption. [ABSTRACT FROM AUTHOR]

In the early 2000s high expectations existed regarding the potential contribution of biofuels to the reduction of greenhouse gas emissions and substitution of fossil fuels in transport. In recent years sobering judgments prevailed. The major barriers for a further expansion of biofuels are their high costs (compared to fossil fuels), moderate ecological performances, limited feedstocks for biofuel production and their competition with food production. The objective of this paper is to investigate the market prospects of biofuels up to the year 2030. It focuses on the three currently most important regions for biofuels production and use: the US, EU and Brazil which in 2010 accounted together for almost three-quarters of global biofuel supply. Our method of approach is based on a dynamic economic framework considering the major cost components of biofuels and corresponding technological learning with respect to capital costs. Moreover, for the analysis of the competitiveness of biofuels with fossil fuels also taxes are considered. The most important result is that under existing tax policies biofuels are cost-effective today and also for the next decades in the regions investigated. However, their potentials are restricted especially due to limited crops areas, and their environmental performance is currently rather modest. The major final conclusions are: (i) To reveal the real future market value of biofuels, a CO 2 based tax system should be implemented for all types of fuels providing a neutral environmental incentive for competition between all types of fossil and renewable fuels; (ii) Moreover, the research and development for all types of biofuels, but especially for second generation biofuels, has to be intensified. [ABSTRACT FROM AUTHOR]

Abstract: Countries are trying to reduce their energy consumption, fossil fuel usage, and greenhouse gas emissions. Recent guidelines generated by various government agencies indicate an increase in the fuel economy, with a reduction in green house gases. The use of both alternative fuel vehicles and renewable energy sources is thus necessary toward achieving this goal. This paper proposes a hydrogen fueling infrastructure design for the Northeastern United States. The design provides an implementation plan for a period of 13 years (from 2013 to 2025). This design gives priority to customer convenience with minimum additional investments for its implementation. Extensive research has been conducted on generating a hydrogen supply from factories and other potential sources that can satisfy demand in the region. Markers (e.g. population density, traffic density, legislation, and growth pattern) have driven the process of demand estimation. [Copyright &y& Elsevier]

Abstract: Carbon capture and storage (CCS) is the only technology available to mitigate greenhouse gas (GHG) emissions from large-scale fossil fuel usage. U.S. and China are the world’s largest GHG emitters. Collaboration between the two nations, therefore, offers the greatest opportunity for achieving meaningful reductions in global GHG emissions. Two countries’ current cooperation on CCS through Clean Energy Research Center based on the U.S.–China Strategic Forum on Clean Energy Cooperation mechanism provides an important initial step towards even closer and stronger cooperation in the future. In this paper, we justify such possibility by discourse on the seemly different but complementary social–political context in two countries including political system, government structure, economic policy, national innovation system, energy strategy, and energy market structure. We further address the key elements of future cooperation model by carefully considering the principle of equality and mutual beneficiary, the role of two countries in the whole value chain according to their comparative advantages, and the scale and mechanism of the funding. A milestone for the cooperation until 2030 is drafted and priority areas for both countries in the cooperation are identified. Such cooperation will provide the imperative leadership for global climate change and speed up the global CCS deployment. [Copyright &y& Elsevier]

Abstract: The life cycle greenhouse gas (GHG) and fossil fuel benefits of black liquor recovery are analyzed. These benefits are due to the production of energy that can be used in the pulping process or sold, and the recovery of the pulping chemicals that would otherwise need to be produced from other resources. The fossil GHG emissions and non-renewable energy consumption of using black liquor in the kraft recovery system are approximately 90% lower than those for a comparable fossil fuel-based system. Across all scenarios, the systems relying on black liquor solids achieve a median reduction of approximately 140 kg CO2 eq./GJ of energy produced, compared to the systems relying on fossil fuels to provide the same energy and pulping chemical production functions. The benefits attributable to the recovery of pulping chemicals vary from 44% to 75% of the total benefit. Applied to the total production of kraft pulp in the U.S., the avoided emissions are equivalent to the total Scopes 1 and 2 emissions from the entire U.S. forest products industry. These results do not depend on the accounting method for biogenic carbon (because biogenic CO2 emissions are the same for the systems compared) and the results are valid across a range of assumptions about the displaced fossil fuel, the GHG-intensity of the electricity grid, the fossil fuels used in the lime kiln, and the level of cogeneration at pulp and paper mills. The benefits occur without affecting the amount of wood harvested or the amount of chemical pulp produced. [Copyright &y& Elsevier]

Abstract: Wind energy is one of the fastest growing sources of power generation in the world. While general public and political support for wind energy is often high, siting wind farms frequently raises concerns in local communities, and individual projects often fail because of effective public opposition. This paper presents the results of a postal and online survey questionnaire that explores public perceptions of wind energy in two of the most important states for wind development, Texas and Iowa. The goal is a better understanding of public reactions to large-scale wind developments as a prerequisite of more widespread use of renewable energy resources. We found a high level of public support for wind energy, with more than two-thirds of respondents being in favor of building more wind farms either in their community or within the U.S. as a whole. Given that the majority of respondents had a very high level of concern for the general environment, we also found that almost two-thirds of respondents counter-intuitively indicated that producing electricity using fossil fuels is not detrimental to the environment, and that they had little concern for global climate change. Our results suggest that arguing for more renewable sources of energy based on reducing our carbon footprint is less persuasive in these communities than simply approaching it from the perspective of wind being a clean and safe source of energy. More than two-thirds of respondents felt their county had benefited economically from the wind farms and that they were a source of job creation in the county. Support for wind power in these communities is associated far more with socioeconomic factors than foundational aesthetic or moral values, with wind farms perceived as the vehicle that will reverse economic decline. [Copyright &y& Elsevier]

One technique for evaluating the costs of energy systems is net energy analysis, which compares the quantity of energy delivered to society by an energy system to the energy used directly and indirectly in the delivery process, a quantity called the energy return on investment (EROI). Such an investigation involves aggregating different energy flows. A variety of methods have been proposed, but none has received universal acceptance. This paper shows that the method of aggregation has crucial effects on the results of the analysis. It is argued that economic approaches such as the index or marginal product method are superior because they account for differences in quality among fuels. The thermal equivalent and quality-corrected EROI for petroleum extraction in the US show the same general pattern: a rise to a maximum in the early 1970s, a sharp decline throughout the 1970s, a recovery in the 1980s, and then another modest decline in the 1990s. However, the quality-corrected EROI is consistently much lower than the thermal equivalent EROI, and it declines faster and to a greater extent than the thermal-equivalent EROI. The results indicate that quality corrections have important effects on the results of energy analyses. The overall decline in the EROI for petroleum extraction in the US suggests that depletion has raised the energy costs of extraction. This is generally consistent with the overall pattern of oil extraction, i.e. both extraction and the EROI for extraction show a decline since the early 1970s. [Copyright &y& Elsevier]

The recent historical increase in energy-related CO 2 emissions globally have put the United States of America's (USA) transportation sector in the spotlight, courtesy of the significantly high pollutant emissions from this particular sector. Taking a cue from this, this paper follows sustainable development goals of the United Nations, and investigates the impact of biomass energy consumption, fossil fuel energy consumption, and economic growth (GDP) on carbon dioxide (CO 2) emissions in the transportation sector of the USA. In doing so, this study also employs the Gregory-Hansen cointegration, Hatemi-J cointegration, cointegration regression (FMOLS, DOLS, and CCR), and Spectral Breitung-Candelon causality test for the period between 1981Q1 and 2019Q4. The findings reveal that (i) a significant nonlinear cointegration among the environmental quality determinants is observed, using the threshold cointegration test. This test determines the structural breaks endogenously and combines two cointegration tests, namely the Gregory-Hansen Cointegration and Hatemi-J Cointegration tests; (ii) while the use of biomass energy consumption and real GDP have a negative effect on CO 2 emissions in the transportation sector, the rising fossil fuel energy consumption is associated with increasing the CO 2 emissions that are stemming from the transportation sector; (iii) in the long-run, biomass energy consumption, fossil fuel energy consumption, and real GDP cause CO 2 emissions to stem from the transportation sector in the USA at different frequency levels. In general, the current study offers policy insights for the transportation sector of the USA and other similar economies that replicate the same conditions. Image 1 • We explore the driving forces of CO 2 emissions in the transport sector for the USA. • We employ advanced time series econometric techniques for empirical analysis. • Biomass energy and real GDP help to mitigate CO 2 emissions in the transport sector. • Fossil fuel energy has a positive impact on CO 2 emissions in the transport sector. • All variables have a causative relationship with CO 2 emissions in the long-run. [ABSTRACT FROM AUTHOR]