scholarly journals Energy performance indicators of wastewater treatment: a field study with 17 Portuguese plants

2015 ◽  
Vol 72 (4) ◽  
pp. 510-519 ◽  
Author(s):  
Catarina Silva ◽  
Maria João Rosa
Keyword(s):  
Wastewater Treatment ◽  
Energy Consumption ◽  
Field Study ◽  
Reference Values ◽  
Performance Indicators ◽  
Electrical Energy ◽  
Energy Performance ◽  
Net Use ◽  
Unit Energy ◽  
Unit Energy Consumption

The energy costs usually represent the second largest part of the running costs of a wastewater treatment plant (WWTP). It is therefore crucial to increase the energy efficiency of these infrastructures and to implement energy management systems, where quantitative performance metrics, such as performance indicators (PIs), play a key role. This paper presents energy PIs which cover the unit energy consumption, production, net use from external sources and costs, and the results used to validate them and derive their reference values. The results of a field study with 17 Portuguese WWTPs (5-year period) were consistent with the results obtained through an international literature survey on the two key parcels of the energy balance – consumption and production. The unit energy consumption showed an overall inverse relation with the volume treated, and the reference values reflect this relation for trickling filters and for activated sludge systems (conventional, with coagulation/filtration (C/F) and with nitrification and C/F). The reference values of electrical energy production were derived from the methane generation potential (converted to electrical energy) and literature data, whereas those of energy net use were obtained by the difference between the energy consumption and production.

scholarly journals Analysis of the Total Unit Energy Consumption of a Car with a Hybrid Drive System in Real Operating Conditions

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3966
Author(s):  
Jarosław Mamala ◽  
Michał Śmieja ◽  
Krzysztof Prażnowski
Keyword(s):  
Energy Consumption ◽  
Internal Combustion Engine ◽  
Electric Drive ◽  
Combustion Engine ◽  
Internal Combustion ◽  
Operating Conditions ◽  
Hybrid Drive ◽  
Total Unit ◽  
Unit Energy ◽  
Unit Energy Consumption

The market demand for vehicles with reduced energy consumption, as well as increasingly stringent standards limiting CO2 emissions, are the focus of a large number of research works undertaken in the analysis of the energy consumption of cars in real operating conditions. Taking into account the growing share of hybrid drive units on the automotive market, the aim of the article is to analyse the total unit energy consumption of a car operating in real road conditions, equipped with an advanced hybrid drive system of the PHEV (plug-in hybrid electric vehicles) type. In this paper, special attention has been paid to the total unit energy consumption of a car resulting from the cooperation of the two independent power units, internal combustion and electric. The results obtained for the individual drive units were presented in the form of a new unit index of the car, which allows us to compare the consumption of energy obtained from fuel with the use of electricity supported from the car’s batteries, during journeys in real road conditions. The presented research results indicate a several-fold increase in the total unit energy consumption of a car powered by an internal combustion engine compared to an electric car. The values of the total unit energy consumption of the car in real road conditions for the internal combustion drive are within the range 1.25–2.95 (J/(kg · m)) in relation to the electric drive 0.27–1.1 (J/(kg · m)) in terms of instantaneous values. In terms of average values, the appropriate values for only the combustion engine are 1.54 (J/(kg · m)) and for the electric drive only are 0.45 (J/(kg · m)) which results in the internal combustion engine values being 3.4 times higher than the electric values. It is the combustion of fuel that causes the greatest increase in energy supplied from the drive unit to the car’s propulsion system in the TTW (tank to wheels) system. At the same time this component is responsible for energy losses and CO2 emissions to the environment. The results were analysed to identify the differences between the actual life cycle energy consumption of the hybrid powertrain and the WLTP (Worldwide Harmonized Light-Duty Test Procedure) homologation cycle.

Effect of the Short Fiber on the NR Composite and the NR-SBR Composite

2012 ◽  
Vol 581-582 ◽  
pp. 552-555
Author(s):  
Cai Jun Liu
Keyword(s):  
Mechanical Properties ◽  
Energy Consumption ◽  
Short Fiber ◽  
Maximum Power ◽  
Mechanical Process ◽  
Contrast Method ◽  
Unit Energy ◽  
Unit Energy Consumption

The influence of the pretreatment polyester short fiber on the mechanical process and the properties of the NR/ SBR compound was studied by using contrast method. The results showed that the maximum power and the unit energy consumption increased because of short fiber, and the temperature also enhanced. So the low rotate speed is better. When the composite were cured, it had much characteristic such as rapid vulcanization speed, short scorch time and vulcanization smooth period. But the mechanical properties were increased. In the end, the microscopic photo of composite with the scanning electronic micrograph was taken.

scholarly journals Benchmarking of energy consumption in municipal wastewater treatment plants – a survey of over 200 plants in Italy

2018 ◽  
Vol 77 (9) ◽  
pp. 2242-2252 ◽  
Author(s):  
M. Vaccari ◽  
P. Foladori ◽  
S. Nembrini ◽  
F. Vitali
Keyword(s):  
Wastewater Treatment ◽  
Energy Consumption ◽  
Municipal Wastewater ◽  
Energy Savings ◽  
Wastewater Treatment Plants ◽  
Specific Energy Consumption ◽  
Oxygen Demand ◽  
Energy Performance ◽  
High Energy ◽  
Municipal Wastewater Treatment

Abstract One of the largest surveys in Europe about energy consumption in Italian wastewater treatment plants (WWTPs) is presented, based on 241 WWTPs and a total population equivalent (PE) of more than 9,000,000 PE. The study contributes towards standardised resilient data and benchmarking and to identify potentials for energy savings. In the energy benchmark, three indicators were used: specific energy consumption expressed per population equivalents (kWh PE−1 year−1), per cubic meter (kWh/m3), and per unit of chemical oxygen demand (COD) removed (kWh/kgCOD). The indicator kWh/m3, even though widely applied, resulted in a biased benchmark, because highly influenced by stormwater and infiltrations. Plants with combined networks (often used in Europe) showed an apparent better energy performance. Conversely, the indicator kWh PE−1 year−1 resulted in a more meaningful definition of a benchmark. High energy efficiency was associated with: (i) large capacity of the plant, (ii) higher COD concentration in wastewater, (iii) separate sewer systems, (iv) capacity utilisation over 80%, and (v) high organic loads, but without overloading. The 25th percentile was proposed as a benchmark for four size classes: 23 kWh PE−1 y−1 for large plants > 100,000 PE; 42 kWh PE−1 y−1 for capacity 10,000 < PE < 100,000, 48 kWh PE−1 y−1 for capacity 2,000 < PE < 10,000 and 76 kWh PE−1 y−1 for small plants < 2,000 PE.

scholarly journals Characterization of the Specific Electrical Energy Consumption of Agrifood Industries in the Central Region of Portugal

2014 ◽  
Vol 590 ◽  
pp. 878-882 ◽  
Author(s):  
P.D. Gaspar ◽  
P.D. Silva ◽  
J. Nunes ◽  
L.P. Andrade
Keyword(s):  
Energy Consumption ◽  
Central Region ◽  
Electrical Energy ◽  
Energy Performance ◽  
Electrical Energy Consumption ◽  
Reference Levels ◽  
Energy Characteristics ◽  
High Level ◽  
Result Analysis

This paper provides a characterization of the electrical energy consumption of agrifood industries located in the central region of Portugal that use refrigeration systems to ensure the food safety. The study is based on the result analysis of survey data and energy characteristics of the participating companies. The agrifood industries included in the survey belong to the following sector: meat, dairy, horticultural, distribution and wine. The comparison of energy indicators for the specific electrical energy consumption of companies of a sector and between sectors is analysed and discussed, providing reference levels for the energy performance of agrifood industries. Since the agrifood sector accounts for high level of energy consumption, the energy performance level knowledge can promote the rational use of energy as well as helping on the decision making of practice measures for the improvement of the energy efficiency.

scholarly journals Reduction of Energy Intensity in Broiler Facilities: Methodology and Strategies

2021 ◽  
Vol 8 ◽  
Author(s):  
Catherine Baxevanou ◽  
Dimitrios Fidaros ◽  
Ilias Giannenas ◽  
Eleftherios Bonos ◽  
Ioannis Skoufos
Keyword(s):  
Energy Consumption ◽  
Energy Saving ◽  
Thermal Energy ◽  
Energy Intensity ◽  
Electrical Energy ◽  
Energy Performance ◽  
Advanced Technology ◽  
Energy Audit ◽  
Wind Potential ◽  
Technology Level

Broiler facilities consume a lot of energy resulting in natural source depletion and greater greenhouse gas emissions. A way to assess the energy performance of a broiler facility is through an energy audit. In the present paper, an energy protocol for an energy audit is presented covering both phases of data collection and data elaboration. The operational rating phase is analytically and extendedly described while a complete mathematical model is proposed for the asset rating phase. The developed energy audit procedure was applied to poultry chambers located in lowland and mountainous areas of Epirus Greece for chambers of various sizes and technology levels. The energy intensity indices varied from 46 to 89 kWh/m2 of chamber area 0.25–0.48 kWh/kg of produced meat or 0.36–1.3 kWh/bird depending on the chamber technology level (insulation, automation, etc.) and the location where the unit was installed. The biggest energy consumer was heating followed by energy consumption for ventilation and cooling. An advanced technology level can improve energy performance by ~ 27%−31%. Proper insulation (4–7 cm) can offer a reduction of thermal energy consumption between 10 and 35%. In adequately insulated chambers, the basic heat losses are due to ventilation. Further energy savings can be achieved with more precise ventilation control. Automation can offer additional electrical energy saving for cooling and ventilation (15–20%). Energy-efficient lights can offer energy saving up to 5%. The use of photovoltaic (PV) technology is suggested mainly in areas where net-metering holds. The use of wind turbines is feasible only when adequate wind potential is available. Solar thermal energy is recommended in combination with a heat pump if the unit's heating and cooling systems use hot/cold water or air. Finally, the local production of biogas with anaerobic fermentation for producing thermal or electrical energy, or cogenerating both, is a choice that should be studied individually for each farm.

scholarly journals Evaluating the Technology Readiness of a Ribbon-Blade Wind Turbine Using NASA’s TRL Method

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7709
Author(s):  
Robert Kasner ◽  
Patrycja Bałdowska-Witos
Keyword(s):  
Energy Consumption ◽  
Wind Turbine ◽  
Technology Readiness ◽  
Technological Readiness ◽  
Modern Computer ◽  
Unit Energy ◽  
Unit Energy Consumption ◽  
Power And Energy ◽  
Turbine Design

The aim of this article was to complete a methodologically original study and evaluation of the technological readiness of an innovative ribbon-blade wind turbine in accordance with NASA’s TRL method. The structural form of the wind turbine unit analyzed herein, featuring a new ribbon turbine design, is distinguished by its safe durability. The circumferential speeds of the points on the turbine circumference were technologically verified positively and have a significant impact on the evaluation indicators of the conversion process, these being efficiency, unit energy consumption, and the quality of the power and energy of the wind power plant. The use of a new turbine design in the wind turbine analyzed herein, a working ribbon unit, resulted in a technological increase in efficiency from 13% to 32% and a reduction in unit internal energy consumption from 18% to 36% compared to the traditional wind turbine design. The TRL NASA-based evaluation herein, which consists of modern computer-aided engineering procedures (CAE standard) as well as IT instrumentation, and which includes nine degrees of technological readiness of an innovative ribbon windmill, falls in line with the standards for smart development based on knowledge and innovation (EU 2020 Strategy).

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