Greenhouse gas emission curves for advanced biofuel supply chains

Most climate change mitigation scenarios that are consistent with the 1.5–2 °C target rely on a large-scale contribution from biomass, including advanced (second-generation) biofuels. However, land-based biofuel production has been associated with substantial land-use change emissions. Previous studies show a wide range of emission factors, often hiding the influence of spatial heterogeneity. Here we introduce a spatially explicit method for assessing the supply of advanced biofuels at different emission factors and present the results as emission curves. Dedicated crops grown on grasslands, savannahs and abandoned agricultural lands could provide 30 EJBiofuel yr−1 with emission factors less than 40 kg of CO2-equivalent (CO2e) emissions per GJBiofuel (for an 85-year time horizon). This increases to 100 EJBiofuel yr−1 for emission factors less than 60 kgCO2e GJBiofuel −1. While these results are uncertain and depend on model assumptions (including time horizon, spatial resolution, technology assumptions and so on), emission curves improve our understanding of the relationship between biofuel supply and its potential contribution to climate change mitigation while accounting for spatial heterogeneity

SEM-EDS investigation on PM10 data collected in Central Italy: Principal Component Analysis and Hierarchical Cluster Analysis

<p>Abstract</p> <p>Background</p> <p>Combined Heat and Power (CHP) systems can provide a range of benefits to users with regards to efficiency, reliability, costs and environmental impact. Furthermore, increasing the amount of electricity generated by CHP systems in the United States has been identified as having significant potential for impressive economic and environmental outcomes on a national scale. Given the benefits from increasing the adoption of CHP technologies, there is value in improving our understanding of how desired increases in CHP adoption can be best achieved. These obstacles are currently understood to stem from regulatory as well as economic and technological barriers. In our research, we answer the following questions: Given the current policy and economic environment facing the CHP industry, what changes need to take place in this space in order for CHP systems to be competitive in the energy market?</p> <p>Methods</p> <p>We focus our analysis primarily on Combined Heat and Power Systems that use natural gas turbines. Our analysis takes a two-pronged approach. We first conduct a statistical analysis of the impact of state policies on increases in electricity generated from CHP system. Second, we conduct a Cost-Benefit analysis to determine in which circumstances funding incentives are necessary to make CHP technologies cost-competitive.</p> <p>Results</p> <p>Our policy analysis shows that regulatory improvements do not explain the growth in adoption of CHP technologies but hold the potential to encourage increases in electricity generated from CHP system in small-scale applications<it>.</it> Our Cost-Benefit analysis shows that CHP systems are only cost competitive in large-scale applications and that funding incentives would be necessary to make CHP technology cost-competitive in small-scale applications.</p> <p>Conclusion</p> <p>From the synthesis of these analyses we conclude that because large-scale applications of natural gas turbines are already cost-competitive, policy initiatives aimed at a CHP market dominated primarily by large-scale (and therefore already cost-competitive) systems have not been effectively directed. Our recommendation is that for CHP technologies using natural gas turbines, policy focuses should be on increasing CHP growth in small-scale systems. This result can be best achieved through redirection of state and federal incentives, research and development, adoption of smart grid technology, and outreach and education.</p

Global commitment towards sustainable energy

Energy is crucial to economic and social development and improves quality of life. However, fossil fuel energy produces greenhouse gases (GHGs) and cannot be sustained for a long time. It is essential to tackle these problems by moving towards renewable and sustainable energy. Some countries, including those in the Arabian Gulf region, are still in the appraisal stage of adopting different forms of renewable energy. This paper reviews the business potential and likely GHG reductions associated with adopting renewable energy in Oman. It is revealed that 1·9 Mt of annual carbon dioxide emissions could be cut by producing 10% of the country’s electricity from renewables. The paper further discusses the global sustainable energy commitment under the UN Framework Convention on Climate Change and reviews the 2030 targets of some countries that are high producers of GHGs. It is anticipated that if all these planned targets are achieved, the total sustainable energy contribution could grow by nearly 11 000 TWh by 2030. These plans provide guidance for those countries still preparing to submit their plans to the UN

Biomass Combined Heat and Power Catalog of Technologies

This is a report on the environmental impacts and potential advantages of using biomass instead of fossil fuels in energy production

ALTERNATIVE FUELS FOR POLLUTION CONTROL: AN EMPIRICAL EVALUATION OF BENEFITS AND COSTS

In July 1989, the Bush administration proposed a new, dramatic approach to constructing clean air legislation. In particular, the Bush proposal calls for using alternative fuels as an important component to reducing urban ozone and carbon monoxide. This paper summarizes the Bush proposal, looks briefly at other options to reduce urban air pollution, and empirically evaluates the cost effectiveness of alternative fuels as an air pollution control strategy. The paper finds that the cost per ton of emissions reduced-the measure of cost effectiveness-varies dramatically as the price of gasoline vis a vis the price of the alternative fuel changes. For this reason, the authors believe that new clean air legislation should allow for great flexibility so as to allow states to incorporate alternative fuels when they are cost effective. If oil prices turn out to be lower than expected, then forcing urban centers to adopt relatively more expensive alternative fuels would impose high costs. Copyright 1990 Western Economic Association International.

Projections of the availability and cost of residues from agriculture and forestry

By-products of agricultural and forestry processes, known as residues, may act as a primary source of renewable energy. Studies assessing the availability of this resource so far offer few insights on the drivers and constraints of the available potential, the associated costs and how the availability may vary across scenarios. This study projects long-term global supply curves of the available potential by using consistent scenarios of agriculture and forestry production, livestock production and fuel use from a spatially explicit integrated assessment model. Particular attention is paid to the drivers and constraints. In the projections residue production is related to agricultural and forestry production and intensification, and the limiting effect of ecological and alternative uses of residues are accounted for. Depending on the scenario, theoretical potential is projected to increase from approximately 120 EJ/yr today to 140-170 EJ/yr by 2100, coming mostly from agricultural production. In order to maintain ecological functions approximately 40% is required to remain in the field, and a further 20-30% is diverted towards alternative uses. Of the remaining potential (approximately 50 EJ/yr in 2100), more than 90%, is available at less than 10$2005/GJ. Crop yield improvements increase residue productivity, albeit at a lower rate. The consequent decrease in agricultural land results in a lower requirement of residues for erosion control. The theoretical potential is most sensitive to baseline projections of agriculture and forestry demand; however this does not necessarily affect the available potential which is relatively constant across scenarios. The most important limiting factors are the alternative uses. Asia and North America account for two thirds of the available potential due to the production of crops with high residue yields and socioeconomic conditions which limit alternative uses

Uncertainty in Carbon Capture and Storage (CCS) deployment projections: a cross-model comparison exercise

Carbon Capture and Storage (CCS) can be a valuable CO2 mitigation option, but what role CCS will play in the future is uncertain. In this paper we analyze the results of different integrated assessment models (IAMs) taking part in the 27th round of the Energy Modeling Forum (EMF) with respect to the role of CCS in long term mitigation scenarios. Specifically we look into the use of CCS as a function of time, mitigation targets, availability of renewables and its use with different fuels. Furthermore, we explore the possibility to relate model results to general and CCS specific model assumptions. The results show a wide range of cumulative capture in the 2010-2100 period (600-3050 GtCO2), but the fact that no model projects less than 600 GtCO2 indicates that CCS is considered to be important by all these models. Interestingly, CCS storage rates are often projected to be still increasing in the second half of this century. Depending on the scenario, at least six out of eight, up to all models show higher storage rates in 2100 than in 2050. CCS shares in cumulative primary energy use are in most models increasing with the stringency of the target or under conservative availability of renewables. The strong variations of CCS deployment projection rates could not be related to the reported differences in the assumptions of the models by means of a cross-model comparison in this sample

Exploring relationships between abundance of non-timber forest product species and tropical forest plant diversity

Despite the importance of non-timber forest products (NTFPs) for local livelihoods in tropical countries and the increasing attention for biodiversity-ecosystem services relationships, it remained unclear how the ecosystem service of NTFP provisioning is related to plant diversity. Although it is generally assumed that plant diversity is positively related to ecosystem services, this had not been assessed for NTFP provisioning. We applied bivariate and multiple regression models to explore the relationships between the abundance of 58 commercially relevant NTFP species and woody plant diversity across 287 plots of tropical forests in Northern Suriname. We found that NTFP abundance showed both positive and negative relationships to plant diversity indicators. In contrast to expectations, NTFP abundance was negatively related to woody species richness. In addition, across the plots disproportionately few (2–6) NTFP species determined >50% of NTFP abundance. The occurrence and the identity of these ‘NTFP oligarchs’ was associated to specific floristic compositions. Overall, more than half, i.e. 55.9%, of the observed variation in NTFP abundance could be explained by a combination of taxonomic and structural plant diversity indicators. Our case study findings are relevant for conservation policies in general. In most countries NTFPs are not on the agenda of governments and current tropical conservation policies often focus on forests with high species richness and/or carbon stocks. Our findings indicate that current policies may not cover valuable forests in terms of high NTFP abundance. To support sustainable NTFP provisioning, additional conservation efforts would need to include those vegetation types with high NTFP abundance