scholarly journals Energy Efficiency of a Small Bioreactor in Various Climatic Zones

2020 ◽  
Vol 63 (4) ◽  
pp. 355-364
Author(s):  
V. G Isakov ◽  
A. A. Abramova ◽  
M. Yu. Dyagelev
Keyword(s):  
Energy Efficiency ◽  
Climatic Conditions ◽  
Low Energy ◽  
Critical Volume ◽  
Heating Period ◽  
Biogas Yield ◽  
Reactor Volume ◽  
Degree Day ◽  
Autonomous Operation ◽  
Average Annual Temperature

The authors proposed a model for estimating the heat balance and energy efficiency of a bioreactor that makes possible for a small-sized reactor operating on a relatively low-energy substrate to determine the critical volume, under which the existing climatic conditions allow year-round fully autonomous operation of the digester, as well as for evaluation the potential energy efficiency of such a bioreactor (output commodity heat). For the numerical characteristics of the climatic zone, it is proposed to use the average annual temperature and/or the “degree-day of the heating period” (DDHP) indicator common in construction heat engineering; the DDHP value more adequately characterizing the unevenness of the average monthly temperature distribution, i.e. degree of climate continentality. At the same time, the value of the critical volume of the bioreactor, at which year-round autonomous operation of the digester operating on the municipal sewage sludge, is possible, varies from 7.5 (Vladikavkaz, DDHP = 3410) to 17.0 m3 (Tomsk, DDHP = 6938), i. e. increases almost in proportion to the degree-day of the heating period. It should be noted that when using a substrate with a high biogas yield, e. g., pig manure (a biogas yield of 40 g/kg is adopted), the critical volume in all cases is less than 1 m3. Such results are relevant only for relatively low-energy raw materials. The nature of changes in the output of commodity heat, depending on the volume of the bioreactor and climatic conditions, is quite expectable, viz. the amount of heat that is useful for business interests is higher, the higher is the reactor volume and the milder is the climate. However, when the reactor volume is less than 5 m3, the non-linearity of the graphs is much higher, i. e. for a designer of especially small bioreactors, it seems mandatory to carry out such calculations. The obtained numerical values can be useful both for the designer of bioreactors and for the customer of the project when evaluating the economic efficiency of the planned new innovations.

scholarly journals Energy Efficiency of a Solar Wall with Transparent Insulation in Polish Climatic Conditions

Energies ◽  
2020 ◽  
Vol 13 (4) ◽  
pp. 859
Author(s):  
Jadwiga Świrska-Perkowska ◽  
Andrzej Kucharczyk ◽  
Jerzy Wyrwał
Keyword(s):  
Energy Efficiency ◽  
Climatic Conditions ◽  
Temperate Climate ◽  
Heating Period ◽  
Conductivity Equation ◽  
Building Envelopes ◽  
Thermal Conductivity Equation ◽  
Proposed Model ◽  
Solar Wall ◽  
Energy Balances

A numerical model of a solar wall (SW) with transparent insulation (TI) is proposed in this article. The model is based on the finite-difference method and thermal conductivity equation, with a heat source term for the absorber. Using this model, the energy efficiency of a solar wall with transparent insulation (SW-TI) with honeycomb insulation made of modified cellulose acetate was analyzed in the case of different climatic conditions prevailing in Poland, different orientations of the envelope, and different insulation thicknesses. Simulations were carried out throughout the whole heating period. Monthly energy balances and temperature distributions for the analyzed envelopes at individual moments of the heating period are the basic results of the simulations. It was found that the use of 108 and 88 mm thick insulation was the most recommended in the considered temperate climate. Placing transparent insulation on a wall with an eastern or western orientation caused the annual heat balance of the envelope to decrease by 24–31% in relation to the value of this balance in the case of a southern orientation. The monthly heat balances obtained using the proposed model give results consistent with the method of calculating heat gains for opaque building envelopes with transparent insulation included in the PN-EN ISO 13790:2008 standard.

Impact of External Shading on Light Comfort and Energy Efficiency in Apartment Buildings

2016 ◽  
Vol 861 ◽  
pp. 485-492 ◽  
Author(s):  
Agnes Iringová
Keyword(s):  
Energy Efficiency ◽  
Heat Loss ◽  
Low Energy ◽  
Heating Period ◽  
Apartment Buildings ◽  
Hygienic Quality ◽  
Low Energy Buildings ◽  
Insulation Quality ◽  
Model Scenarios

The paper is focused on an example of volume solution of a superstructure designed within allowable legislative limits and its impact on light comfort in shaded flats. It deals with issues such as : optimizing allowable amount of external shade in relation to sustainable hygienic quality of residential environment, an impact of superstructure ́s shade on insolation time in affected flats and consequently on passive solar gain intensity of apartment buildings, as well as evaluation of energy efficiency of infill walls in compensating of their heat loss in heating period, depending on the amount of external shading, their orientation, and thermo-insulation quality in all model scenarios - current, legislatively allowable, and optimized. It solves compatibility of optimized shading in terms of hygienic quality in relation to the increased efficiency of solar gains utilization to cover heat loss by heat-exchange shell in contemporary and prospective low-energy buildings.

scholarly journals Energy efficiency of the accumulation wall with a transparent insulation

2018 ◽  
Vol 174 ◽  
pp. 01013 ◽  
Author(s):  
Jadwiga Świrska-Perkowska ◽  
Karolina Jęglet
Keyword(s):  
Energy Efficiency ◽  
Energy Balance ◽  
Numerical Model ◽  
Climatic Conditions ◽  
Heating Period ◽  
Temperature Distributions ◽  
Solar Wall ◽  
Low Irradiation

This paper presents a numerical model of an accumulating solar wall with transparent insulation (ASW-TI). The objective of the simulation was to evaluate the energy efficiency of ASW-TI for different climatic conditions in Poland, i.e. for high, medium, and low irradiation. For each climate, the calculations were made for the entire heating period. As a result, temperature distributions in a wall at different times of the process and the energy balance of the wall in particular months and during the entire heating period were obtained.

Measurements of electric energy consumption in a low energy building in Slovak climatic conditions

2012 ◽  
Vol 7 (3) ◽  
pp. 23-32 ◽  
Author(s):  
Miloslav Bagoňa ◽  
Dušan Katunský ◽  
Martin Lopušniak ◽  
Marián Vertaľ
Keyword(s):  
Energy Consumption ◽  
Electric Energy ◽  
Climatic Conditions ◽  
Low Energy ◽  
Electric Energy Consumption

scholarly journals Integrated economic and environmental building classification and optimal seismic vulnerability/energy efficiency retrofitting

2021 ◽  
Author(s):  
Martina Caruso ◽  
Rui Pinho ◽  
Federica Bianchi ◽  
Francesco Cavalieri ◽  
Maria Teresa Lemmo
Keyword(s):  
Energy Efficiency ◽  
Life Cycle ◽  
Seismic Hazard ◽  
Environmental Impacts ◽  
Classification System ◽  
Seismic Vulnerability ◽  
Performance Metrics ◽  
Climatic Conditions ◽  
Economic Losses ◽  
Operational Energy

AbstractA life cycle framework for a new integrated classification system for buildings and the identification of renovation strategies that lead to an optimal balance between reduction of seismic vulnerability and increase of energy efficiency, considering both economic losses and environmental impacts, is discussed through a parametric application to an exemplificative case-study building. Such framework accounts for the economic and environmental contributions of initial construction, operational energy consumption, earthquake-induced damage repair activities, retrofitting interventions, and demolition. One-off and annual monetary expenses and environmental impacts through the building life cycle are suggested as meaningful performance metrics to develop an integrated classification system for buildings and to identify the optimal renovation strategy leading to a combined reduction of economic and environmental impacts, depending on the climatic conditions and the seismic hazard at the site of interest. The illustrative application of the framework to an existing school building is then carried out, investigating alternative retrofitting solutions, including either sole structural retrofitting options or sole energy refurbishments, as well as integrated strategies that target both objectives, with a view to demonstrate its practicality and to explore its ensuing results. The influence of seismic hazard and climatic conditions is quantitatively investigated, by assuming the building to be located into different geographic locations.

Role of BIM and energy simulation tools in designing zero-net energy homes

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Shahryar Habibi
Keyword(s):  
Energy Efficiency ◽  
Built Environment ◽  
Design Process ◽  
Simulation Software ◽  
Energy Simulation ◽  
Low Energy ◽  
Net Energy ◽  
Content Type ◽  
Zero Net Energy

Purpose The purpose of this study is to design a zero-energy home, which is known to be capable of balancing its own energy production and consumption close to zero. Development of low-energy homes and zero-net energy houses (ZEHs) is vital to move toward energy efficiency and sustainability in the built environment. To achieve zero or low energy targets in homes, it is essential to use the design process that minimizes the need for active mechanical systems. Design/methodology/approach The methodology discussed in this paper consists of an interfacing building information modeling (BIM) tool and a simulation software to determine the potential influence of phase change materials on designing zero-net energy homes. Findings BIM plays a key role in advancing methods for architects and designers to communicate through a common software platform, analyze energy performance through all stages of the design and construction process and make decisions for improving energy efficiency in the built environment. Originality/value This paper reviews the literature relevant to the role of BIM in helping energy simulation for the performance of residential homes to more advanced levels and in modeling the integrated design process of ZEHs.

Application Of Solar Maps In Design Of Generalposition Shading Devices

2020 ◽  
pp. 105-109
Author(s):  
Alexander T. Dvoretsky ◽  
Oleg V. Sergeichuk ◽  
Alexander V. Spiridonov
Keyword(s):  
Energy Efficiency ◽  
Solar Radiation ◽  
General Position ◽  
Horizontal Plane ◽  
Heating Period ◽  
Cooling Period ◽  
Efficiency Calculation ◽  
Shading Devices ◽  
Building Cooling ◽  
Simplified Formula

For insolation calculations and design of shading devices (SD) comprising plane sections or fins, the method based on solar maps shall be preferred because of its high descriptiveness and universality.The article describes the algorithm of design of a general-position SD using a solar map and a shade clinometer. An example of calculation of SD geometry parameters such as fin slopes with the horizontal plane and the facade plane, distance between the fins with consideration of screening of the translucent structure during the building cooling period and of transmission of solar radiation during its heating period is given in the article. A simplified formula of a general-position SD energy efficiency calculation is proposed.

scholarly journals Analysis of climate change in Dnipropetrovsk Region

2017 ◽  
pp. 43-51
Author(s):  
V. V. Hrynchak
Keyword(s):  
Climate Change ◽  
Air Temperature ◽  
Climate Changes ◽  
Absolute Temperature ◽  
Climatic Conditions ◽  
Annual Precipitation ◽  
Temperature And Precipitation ◽  
Weather Observations ◽  
Average Annual Temperature

The decision about writing this article was made after familiarization with the "Brief Climatic Essay of Dnepropetrovsk City (prepared based on observations of 1886 – 1937)" written by the Head of the Dnipropetrovsk Weather Department of the Hydrometeorological Service A. N. Mikhailov. The guide has a very interesting fate: in 1943 it was taken by the Nazis from Dnipropetrovsk and in 1948 it returned from Berlin back to the Ukrainian Hydrometeorological and Environmental Directorate of the USSR, as evidenced by a respective entry on the Essay's second page. Having these invaluable materials and data of long-term weather observations in Dnipro city we decided to analyze climate changes in Dnipropetrovsk region. The article presents two 50-year periods, 1886-1937 and 1961-2015, as examples. Series of observations have a uniform and representative character because they were conducted using the same methodology and results processing. We compared two main characteristics of climate: air temperature and precipitation. The article describes changes of average annual temperature values and absolute temperature values. It specifies the shift of seasons' dates and change of seasons' duration. We studied the changes of annual precipitation and peculiarities of their seasonable distribution. Apart from that peculiarities of monthly rainfall fluctuations and their heterogeneity were specified. Since Dnipro city is located in the center of the region the identified tendencies mainly reflect changes of climatic conditions within the entire Dnipropetrovsk region.

Sign in / Sign up

Export Citation Format

Share Document