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The Greenhouse Gas Protocol ‘Corporate Accounting and Reporting Standard’ (Corporate Standard) and the EU frameworks of guarantees of origin (GO) and emissions disclosure of energy carriers are intended to inform decision-making and reduce GHG emissions. This study analyses how decisions on purchases of electricity and district heating and decisions on combined heat and power (CHP) production are incentivised by the Corporate Standard and EU frameworks. It also analyses how the EU frameworks relate to CO 2 emissions reductions through CHP production. Using a consequential CO 2 assessment method for comparison, the study shows that purchasing decisions supported by the Corporate Standard or the GO scheme can increase total CO 2 emissions. It also shows that the Corporate Standard and EU frameworks can counteract CHP production and its contribution to CO 2 emissions reduction. We recommend that consequential GHG assessment methods be used for emissions reduction decisions, including when designing policy instruments aimed at emissions reduction. [ABSTRACT FROM AUTHOR]

Combined heat and power (CHP) systems are a proven technology to reduce emissions. A methodology was presented to compare the economic feasibility of fuel cell-based CHP systems with more alternative prime movers (microturbine and gas turbine). For demonstration purposes, the methodology was applied to three distinct case studies of varying size. The developed methodology allowed for the analysis of the system from various economic points of view. Because of the scarcity of complete equation sets modeling the off-design performance of fuel cells, several novel equations were proposed. All systems utilizing alternative prime movers were unprofitable. The fuel cell-based systems exhibited some economic potential; however, the results showed it would take close to the entire system lifetime to recover the capital costs. This is consistent with the reviewed literature and hence validates the new methodology and partial load equations proposed. Based on this analysis the fuel cell-based system for the medium sized case study showed the most economic potential. Because of the susceptibility of emerging technologies (fuel cells) to changes in capital costs, an in-depth sensitivity analysis was performed. The analysis showed that a 5% decrease in capital costs could reduce the payback period by as much as six months. This indicates that only a small decrease in price is necessary to potentially lead to the adoption of these systems in the near future. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article focuses on the policies related to the combined heat and power (CHP) Technology. Topics discussed include organization for the establishment and regulation of the CHP legislatives, financial incentive program producing barriers for the private companies using CHP technologies and financial benefits for the CHP technology businesses. It also discusses various environmental benefits of the technology.

Highlights: [•] A two-stage optimal method is presented for CCHP microgrid system. [•] Economic and environmental performance are considered as assessment indicators. [•] Application case demonstrates its good economic and environmental performance. [ABSTRACT FROM AUTHOR]

In the endeavor of optimizing the sustainability of bioenergy production in Denmark, this consequential life cycle assessment (LCA) evaluated the environmental impacts associated with the production of heat and electricity from one hectare of Danish arable land cultivated with three perennial crops: ryegrass (Lolium perenne), willow (Salix viminalis) and Miscanthus giganteus. For each, four conversion pathways were assessed against a fossil fuel reference: (I) anaerobic co-digestion with manure, (II) gasification, (III) combustion in small-to-medium scale biomass combined heat and power (CHP) plants and IV) co-firing in large scale coal-fired CHP plants. Soil carbon changes, direct and indirect land use changes as well as uncertainty analysis (sensitivity, MonteCarlo) were included in the LCA. Results showed that global warming was the bottleneck impact, where only two scenarios, namely willow and Miscanthus co-firing, allowed for an improvement as compared with the reference (-82 and -45 t CO2-eq. ha-1, respectively). The indirect land use changes impact was quantified as 310 ± 170 t CO2-eq. ha-1, representing a paramount average of 41% of the induced greenhouse gas emissions. The uncertainty analysis confirmed the results robustness and highlighted the indirect land use changes uncertainty as the only uncertainty that can significantly change the outcome of the LCA results. [ABSTRACT FROM AUTHOR]

Today coal and other fossil fuels share 40% and 20% of the world's total electricity respectively. Fossil fuels playing an important role on CO2 emissions which has the greatest negative effect on greenhouse, causing 55% of the global warming. To stop negative effect on greenhouse CO2 emissions should be decreased. For that reason the CO2 emission technology of the power plants is necessary to be developed and replaced by a zero emission technology. Zero and near zero emissions power plant technologies and their cycles, and important cogeneration cycles are analyzed by the first law of the thermodynamic. Oxyfuel and water cycles' heat and electrical powers compared with sample and recuperated cycles. First law of the thermodynamic efficiency of the oxyfuel and water cycles are found less 8% than sample and recuperated cycles because of air separated unit work to separate oxygen (2-3%) and compressing work of CO2 (5-6%). For the thermodynamic analyze a computer program which its' FORTRAN codes are written by us. The results of this study are also compared with the literature and found that appropriate. [ABSTRACT FROM AUTHOR]

Abstract: Small-scale distributed cogeneration technologies represent a key resource to increase generation efficiency and reduce greenhouse gas emissions with respect to conventional separate production means. However, the diffusion of distributed cogeneration within urban areas, where air quality standards are quite stringent, brings about environmental concerns on a local level. In addition, partial-load emission worsening is often overlooked, which could lead to biased evaluations of the energy system environmental performance. In this paper, a comprehensive emission assessment framework suitable for addressing distributed cogeneration systems is formulated. Local and global emission impact models are presented to identify upper and lower boundary values of the environmental pressure from pollutants that would be emitted from reference technologies, to be compared to the actual emissions from distributed cogeneration. This provides synthetic information on the relative environmental impact from small-scale CHP sources, useful for general indicative and non-site-specific studies. The emission models are formulated according to an electrical output-based emission factor approach, through which off-design operation and relevant performance are easily accounted for. In particular, in order to address the issues that could arise under off-design operation, an equivalent load model is incorporated within the proposed framework, by exploiting the duration curve of the cogenerator loading and the emissions associated to each loading level. In this way, it is possible to quantify the contribution to the emissions from cogeneration systems that might operate at partial loads for a significant portion of their operation time, as for instance in load-tracking applications. Suitability of the proposed methodology is discussed with respect to hazardous air pollutants such as NO x and CO, as well as to greenhouse gases such as CO2. Two case study applications based on the emission data of real microturbines are illustrated in order to highlight the effectiveness of the proposed assessment techniques. The numerical results exemplify the emission impact of distributed cogeneration systems operating under general and realistic loading conditions with respect to average and state-of-the-art conventional technologies. [Copyright &y& Elsevier]