scholarly journals Cogeneration Plant on Biomass - Case Study

2018 ◽  
Vol 18 (2) ◽  
pp. 7-11 ◽  
Author(s):  
A. Enescu ◽  
E. Diaconu

AbstractThe concept of cogeneration defines the simultaneous production with the same installation of electric and thermal energy (in the form of hot water or steam). High-efficiency cogeneration implies that cogeneration production should ensure primary energy savings of at least 10% compared to the reference values of separate production of electricity and heat. This paper presents the process of functioning of a cogeneration plant, operating in the Suceava county, Romania, referring to the actual values regarding the consumption and the proportions of the raw material on the one hand and the energy produced on the other. It also describes the entire production process as well as the impact on the environment, the social and economic aspects of the implementation of such a project.

Energies ◽  
2018 ◽  
Vol 11 (7) ◽  
pp. 1836 ◽  
Author(s):  
Kwon Park ◽  
Seiyong Kim

Recently, Korea has become increasingly interested in unused, but possibly useful energy resources, due to the world-wide controversy over nuclear power and limitations in renewable energy production. Among these unused resources, the water that is produced in our surroundings is available as a potential energy source for heating, cooling and domestic hot water. This water is relatively stable on the supply side, available as a high-efficiency source in all seasons, and is continuously replenished without polluting the environment. This paper analyses the energy savings generated based on the actual use of a sustainable heating and cooling system that operates using the water escaping from a nearby building. The results indicate the value of protecting the environment as well as reducing energy consumption and associated costs.


2021 ◽  
Vol 25 (1) ◽  
pp. 551-562
Author(s):  
Stanislav Chicherin ◽  
Andrey Zhuikov ◽  
Mikhail Kolosov ◽  
Lyazzat Junussova ◽  
Madina Aliyarova ◽  
...  

Abstract Temperature difference between supply and return distribution medium (water) is a vital factor when assessing the efficiency of a district heating (DH) substation. An accounting for fluctuations and differences of the heat consumption/generation is the key problem in planning DH system operation. The influence of the fluctuating energy consumption on a DH system was studied with actual data, using the DH systems of the Russian cities Krasnoyarsk and Omsk as a case study. Information is visualized in the form of graphs and charts, orderly and clearly comparing certain points. The data includes supply and return temperatures, and heat demand. Clearly visible state of high return temperatures induces more bottleneck problems as the flow increases. At the same time, in 2019, the total heat demand was 21 008 MW. This is more than 5 % than in 2020, assuming 100 % of consumers connected. The reasons for this trend are: decreasing total housing area, no incentive for the buildings in newly built-up areas to be connected to the DH system, poor service motivating business facilities to disconnect from the system. When the primary energy consumption related to the warmer climate and behaviour of business sector decreases, the DH system requires renovation. It is possible to reduce network return temperature during some months of the year. The reason is that, a high temperature difference is essential to maintain high efficiency and minimize fuel and pumping cost, it also enables more customers to be connected to a DH system without increasing pipe dimensions of a network.


Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 801
Author(s):  
Gianluca Valenti ◽  
Aldo Bischi ◽  
Stefano Campanari ◽  
Paolo Silva ◽  
Antonino Ravidà ◽  
...  

Stirling units are a viable option for micro-cogeneration applications, but they operate often with multiple daily startups and shutdowns due to the variability of load profiles. This work focused on the experimental and numerical study of a small-size commercial Stirling unit when subjected to cycling operations. First, experimental data about energy flows and emissions were collected during on–off operations. Second, these data were utilized to tune an in-house code for the economic optimization of cogeneration plant scheduling. Lastly, the tuned code was applied to a case study of a residential flat in Northern Italy during a typical winter day to investigate the optimal scheduling of the Stirling unit equipped with a thermal storage tank of diverse sizes. Experimentally, the Stirling unit showed an integrated electric efficiency of 8.9% (8.0%) and thermal efficiency of 91.0% (82.2%), referred to as the fuel lower and, between parenthesis, higher heating value during the on–off cycling test, while emissions showed peaks in NOx and CO up to 100 ppm but shorter than a minute. Numerically, predictions indicated that considering the on–off effects, the optimized operating strategy led to a great reduction of daily startups, with a number lower than 10 per day due to an optimal thermal storage size of 4 kWh. Ultimately, the primary energy saving was 12% and the daily operational cost was 2.9 €/day.


Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 447
Author(s):  
Miguel Alfonso Quiñones-Reveles ◽  
Víctor Manuel Ruiz-García ◽  
Sarai Ramos-Vargas ◽  
Benedicto Vargas-Larreta ◽  
Omar Masera-Cerutti ◽  
...  

This study aimed to evaluate and compare the relationship between chemical properties, energy efficiency, and emissions of wood and pellets from madroño Arbutus xalapensis Kunth, tázcate Juniperus deppeana Steud, and encino colorado Quercus sideroxyla Humb. & Bonpl. in two gasifiers (top-lit-up-draft (T-LUD) and electricity generation wood camp stove (EGWCS)) in order to determine the reduction of footprint carbon. In accordance with conventional methodologies, we determined the extracts and chemical components (lignin, cellulose, holocellulose), and the immediate analyses were carried out (volatile materials, fixed carbon, ash content and microanalysis of said ash), as well as the evaluation of emission factors (total suspended particulate matter (PM2.5), CO, CO2, CH4, black carbon (BC), elemental carbon (EC), and organic carbon (OC)). The results were statistically analyzed to compare each variable among species and gasifiers. The raw material analyzed showed how the pH ranged from 5.01 to 5.57, and the ash content ranged between 0.39 and 0.53%. The content values of Cu, Zn, Fe, Mg, and Ca ranged from 0.08 to 0.22, 0.18 to 0.19, 0.38 to 0.84, 1.75 to 1.90, and 3.62 to 3.74 mg kg−1, respectively. The extractive ranges from cyclohexane were 2.48–4.79%, acetone 2.42–4.08%, methanol 3.17–7.99%, and hot water 2.12–4.83%. The range of lignin was 18.08–28.60%. The cellulose content ranged from 43.30 to 53.90%, and holocellulose from 53.50 to 64.02%. The volatile material range was 81.2–87.42%, while fixed carbon was 11.30–17.48%; the higher heating value (HHV) of raw material and pellets presented the ranges 17.68–20.21 and 19.72–21.81 MJ kg−1, respectively. Thermal efficiency showed statistically significant differences (p < 0.05) between pellets and gasifiers, with an average of 31% Tier 3 in ISO (International Organization for Standardization) for the T-LUD and 14% (ISO Tier 1) for EGWCS, with Arbutus xalapensis being the species with the highest energy yield. The use of improved combustion devices, as well as that of selected raw material species, can reduce the impact of global warming by up to 33% on a cooking task compared to the three-stone burner.


Arts ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 47
Author(s):  
Adelaide Duarte ◽  
Ana Letícia Fialho ◽  
Marta Pérez-Ibáñez

The spread of the COVID-19 pandemic worldwide, and the restrictions imposed by the social distance and the enforced confinement, are having an impact on the art markets globally. The aim of this article is to evaluate the impact of an external shock in the primary art market, using three countries as a case study: Portugal, Spain, and Brazil. These geographies have in common being at the margins in the art market’s main art hubs. It is intended to analyze how agents are responding to the new context, according to the data gathered within the gallery sector. The methods applied in the research are a combination of surveys carried out by the authors, field-based observation, along with an academic literature review, complemented by international and national reports analysis. The study’s main findings allow us to characterize the art market as a very resilient sector that energetically responded to the crisis, able to adapt and overcome challenges imposed by the new pandemic situation. Contemporary art galleries expanded digital activities, kept participating in art fairs hybrid models, continued to focus on internationalization, and pointed to the strengthening of public policies towards the sector and partnerships as key strategies to overcome the crisis.


2006 ◽  
Vol 129 (2) ◽  
pp. 226-234
Author(s):  
Robert Hendron ◽  
Mark Eastment ◽  
Ed Hancock ◽  
Greg Barker ◽  
Paul Reeves

Building America (BA) partner McStain Neighborhoods built the Discovery House in Loveland, CO, with an extensive package of energy-efficient features, including a high-performance envelope, efficient mechanical systems, a solar water heater integrated with the space-heating system, a heat-recovery ventilator (HRV), and ENERGY STAR appliances. The National Renewable Energy Laboratory (NREL) and Building Science Consortium conducted short-term field-testing and building energy simulations to evaluate the performance of the house. These evaluations are utilized by BA to improve future prototype designs and to identify critical research needs. The Discovery House building envelope and ducts were very tight under normal operating conditions. The HRV provided fresh air at a rate of about 35L∕s(75cfm), consistent with the recommendations of ASHRAE Standard 62.2. The solar hot water system is expected to meet the bulk of the domestic hot water (DHW) load (>83%), but only about 12% of the space-heating load. DOE-2.2 simulations predict whole-house source energy savings of 54% compared to the BA Benchmark (Hendron, R., 2005 NREL Report No. 37529, NREL, Golden, CO). The largest contributors to energy savings beyond McStain’s standard practice are the solar water heater, HRV, improved air distribution, high-efficiency boiler, and compact fluorescent lighting package.


Legal Studies ◽  
2021 ◽  
pp. 1-17
Author(s):  
Rebecca Probert ◽  
Stephanie Pywell

Abstract During 2020, weddings were profoundly affected by the Covid-19 pandemic. During periods of lockdown few weddings could take place, and even afterwards restrictions on how they could be celebrated remained. To investigate the impact of such restrictions, we carried out a survey of those whose plans to marry in England and Wales had been affected by Covid-19. The 1,449 responses we received illustrated that the ease and speed with which couples had been able to marry, and sometimes whether they had been able to marry at all, had depended not merely on the national restrictions in place but on their chosen route into marriage. This highlights the complexity and antiquity of marriage law and reinforces the need for reform. The restrictions on weddings taking place also revealed the extent to which couples valued getting married as opposed to having a wedding. Understanding both the social and the legal dimension of weddings is important in informing recommendations as to how the law should be changed in the future, not merely to deal with similar crises but also to ensure that the general law is fit for purpose in the twenty-first century.


2013 ◽  
Vol 671-674 ◽  
pp. 496-499 ◽  
Author(s):  
Ming Yang Wang ◽  
Yun Peng Chu ◽  
Yong Yao ◽  
Yu Ping Zhu

China is a developing country, and also a quake-prone country. On the one hand is the Special national conditions that per capita energy shortage and frequent earthquakes, on the other hand is the social economy development and people's living environment requirements continue to increase, both of them raised new requirement of China’s residence system development. Light steel structure residence is energy conservation , environmental protection, safety and seismic, these unique advantages just to meet the current development of residential industry in China, so it has a good development prospect. This article start from the realistic background, around the application and development of our country’s light steel structure residence presently, mainly introduced the characteristics of light steel structure residence, the impact of construction industry, and the social benefits, environmental benefits, housing industrialization effective and comprehensive benefits it can produce.


2020 ◽  
Vol 7 (2) ◽  
pp. 211-215
Author(s):  
Sogimin Sogimin

This research describes the cultural obstacles in the communication oral and written between native speaker and non native speaker in English.  The obstacles of cultural is one of main obstacles in the  two peoples of communication in the different culural. The research,especially describes the one case of communication between Indonesian people and British people in the social media WhatsApp. The main data of the research is the communication transcript in the social media WhatsApp. Besides of that, the data comes from the interview with the responden.             The research is the case study of the Indonesian people and British people. The data analysis uses qualitative and descriptive method. The result of research shows the miscommunication from different cultural in English. This miscommunication not only caused of the skill of language(language competence) but also difference of cultural between of two peoples. Suggested  to the English learner that  not only learns in the languages aspects but also learns in the cultural aspects, because both of them coud not separate and interplay each others.


2020 ◽  
pp. 177-192
Author(s):  
Iman Hegazy

Public spaces are defined as places that should be accessible to all inhabitants without restrictions. They are spaces not only for gathering, socializing and celebrating but also for initiating discussions, protesting and demonstrating. Thus, public spaces are intangible expressions of democracy—a topic that the paper tackles its viability within the context of Alexandria, case study Al-Qaed Ibrahim square. On the one hand, Al-Qaed Ibrahim square which is named after Al-Qaed Ibrahim mosque is a sacred element in the urban fabric; whereas on the other it represents a non-religious revolutionary symbol in the Alexandrian urban public sphere. This contradiction necessitates finding an approach to study the characteristic of this square/mosque within the Alexandrian context—that is to realize the impact of the socio-political events on the image of Al-Qaed Ibrahim square, and how it has transformed into a revolutionary urban symbol and yet into a no-public space. The research revolves around the hypothesis that the political events taking place in Egypt after January 25th, 2011, have directly affected the development of urban public spaces, especially in Alexandria. Therefore methodologically, the paper reviews the development of Al-Qaed Ibrahim square throughout the Egyptian socio-political changes, with a focus on the square’s urban and emotional contextual transformations. For this reason, the study adheres to two theories: the "city elements" by Kevin Lynch and "emotionalizing the urban" by Frank Eckardt. The aim is not only to study the mentioned public space but also to figure out the changes in people’s societal behaviour and emotion toward it. Through empowering public spaces, the paper calls the different Egyptian political and civic powers to recognize each other, regardless of their religious, ethnical or political affiliations. It is a step towards replacing the ongoing political conflicts, polarization, and suppression with societal reconciliation, coexistence, and democracy.


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