Energy efficiency assessment of China wastewater treatment plants by unit energy consumption per kg COD removed

2021 ◽  
pp. 1-41
Author(s):  
Jinze Li ◽  
Walter Z. Tang ◽  
Li Gu
Keyword(s):  
Energy Efficiency ◽  
Wastewater Treatment ◽  
Energy Consumption ◽  
Wastewater Treatment Plants ◽  
Efficiency Assessment ◽  
Unit Energy ◽  
Unit Energy Consumption

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 Modeling and Forecasting End-Use Energy Consumption for Residential Buildings in Kuwait Using a Bottom-Up Approach

Energies ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 1981 ◽  
Author(s):  
Turki Alajmi ◽  
Patrick Phelan
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Air Conditioning ◽  
Energy Profile ◽  
Bottom Up ◽  
Unit Energy ◽  
The Future ◽  
Energy Consuming ◽  
Unit Energy Consumption ◽  
End Use

To meet the rapid-growing demand for electricity in Kuwait, utility planners need to be informed on the energy consumption to implement energy efficiency measures to manage sustainable load growth and avoid the high costs of increasing generation capacities. The first step of forecasting the future energy profile is to establish a baseline for Kuwait (i.e., a business-as-usual reference scenario where no energy efficiency incentives were given and the adoption of energy efficient equipment is purely market-driven). This paper presents an investigation of creating a baseline end-use energy profile until 2040 for the residential sector in Kuwait by using a bottom-up approach. The forecast consists of mainly two steps: (1) Forecasting the quantity of the residential energy-consuming equipment in the entire sector until 2040 where this paper used a stock-and-flow model that accounted for the income level, electrification, and urbanization rate to predict the quantify of the equipment over the years until 2040, and (2) calculate the unit energy consumption (UEC) for all equipment types using a variety of methods including EnergyPlus simulation models for cooling equipment. By combining the unit energy consumption and quantity of the equipment over the years, this paper established a baseline energy use profile for different end-use equipment for Kuwait until 2040. The results showed that the air conditioning loads accounted for 67% of residential electrical consumption and 72% of residential peak demand in Kuwait. The highest energy consuming appliances were refrigerators and freezers. Additionally, the air conditioning loads are expected to rise in the future, with an average annual growth rate of 2.9%, whereas the lighting and water heating loads are expected to rise at a much lower rate.

Analysis of Energy Consumption and Mode of Energy Saving of Rotary Wheel

2011 ◽  
Vol 374-377 ◽  
pp. 451-455
Author(s):  
Ming Yue ◽  
Yun Fei Ding ◽  
Hui Jun Wu
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
Heat Pump ◽  
Efficiency Evaluation ◽  
Evaluation Standard ◽  
Unit Energy ◽  
Unit Energy Consumption ◽  
System Energy ◽  
Energy Efficiency Evaluation ◽  
Current Energy

A model of rotary wheel combined with heat pump regeneration was presented and an experimental investigation on it was also carried out. Five normal kinds of dehumidification efficiency evaluation standard were introduced in view of the existing various dehumidifying method while the current energy efficiency evaluation indices were analyzed. SMER which defines the dehumidification quantity of unit energy consumption and dehumidification system energy efficiency were introduced and used to compare energy consumption of rotary wheel with or without heat pump. The comparative analysis showed that the system of rotary wheel combined with heat pump regeneration could significantly improve SMER and dehumidification system energy efficiency of rotary wheel.

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.

scholarly journals Forecasting Energy Consumption of Wastewater Treatment Plants with a Transfer Learning Approach for Sustainable Cities

Electronics ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1149
Author(s):  
Pedro Oliveira ◽  
Bruno Fernandes ◽  
Cesar Analide ◽  
Paulo Novais
Keyword(s):  
Wastewater Treatment ◽  
Energy Consumption ◽  
Transfer Learning ◽  
Short Term Memory ◽  
Wastewater Treatment Plants ◽  
Learning Approach ◽  
Sustainable Cities ◽  
Short Term ◽  
Long Short Term Memory ◽  
Gated Recurrent Units

A major challenge of today’s society is to make large urban centres more sustainable. Improving the energy efficiency of the various infrastructures that make up cities is one aspect being considered when improving their sustainability, with Wastewater Treatment Plants (WWTPs) being one of them. Consequently, this study aims to conceive, tune, and evaluate a set of candidate deep learning models with the goal being to forecast the energy consumption of a WWTP, following a recursive multi-step approach. Three distinct types of models were experimented, in particular, Long Short-Term Memory networks (LSTMs), Gated Recurrent Units (GRUs), and uni-dimensional Convolutional Neural Networks (CNNs). Uni- and multi-variate settings were evaluated, as well as different methods for handling outliers. Promising forecasting results were obtained by CNN-based models, being this difference statistically significant when compared to LSTMs and GRUs, with the best model presenting an approximate overall error of 630 kWh when on a multi-variate setting. Finally, to overcome the problem of data scarcity in WWTPs, transfer learning processes were implemented, with promising results being achieved when using a pre-trained uni-variate CNN model, with the overall error reducing to 325 kWh.

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.

Sign in / Sign up

Export Citation Format

Share Document