Cleaner Energy Systems最新文献

A sizable amount of wastewater is produced every day. Wastewater treatment is required to safeguard the environment, human health, flora, and aquatic life. However, wastewater treatment is an expensive operation on one hand, but on the other hand, wastewater contains five to ten times the energy needed for treatment in the form of chemical energy. This energy is accessible via biological processes. Wastewater contains potential and kinetic energy in addition to chemical energy, and it can be harnessed to generate hydropower. Any country must have a central inventory of wastewater in order to harvest this energy. To harness renewable energy from wastewater sector, it is necessary to have a central database for wastewater generation with type of wastewater and its parameters. Unfortunately, Bangladesh lacks a reliable inventory of national wastewater generation, composition, and attributes that may be utilized for estimating wastewater's potential energy output. Therefore, the aim of this research is to estimate the annual total domestic and industrial wastewater output in Bangladesh and estimate its energy recovery potentials. To estimate domestic wastewater (DWW) and industrial wastewater (IWW), an income-based estimating technique and industry-based reports/literature, respectively have been used. Few novel technologies, such as up-flow anaerobic sludge blankets (UASB), anaerobic digestion (AD), and micro hydropower plants (MHP), and five scenarios using only half of the total wastewater (DWW & IWW) have been considered for estimating the energy recovery potential of wastewater. For the hydropower evaluation using MHP, the unit total head is assumed, whereas the average chemical oxygen demand (COD) has been considered for the energy potential assessment of the UASB and AD. Techno-economic analysis (TEA) steps have been also discussed. Results indicate that the expected annual output of DWW and IWW is 4874 million m³ /yr. and 452 million m³ /yr., respectively. In terms of energy potential, scenario 2 has the highest (1986 Giga watt-hour equivalent (GWh)/yr.)), followed by scenario 1 (1857 GWh/yr.), scenario 5 (1770 GWh/yr.), scenario 3 (1401 GWh/yr.), and scenario 4 (976 GWh/yr.). This rigorous research will open up new horizons by attracting the attention not only of Bangladeshi researchers, but also of the international community.

World energy consumption will grow by almost 50 % between 2018 and 2050, resulting in a 79 % increase in electricity generation over this period. In general, renewable energy has been an important source of electricity generation for several years due to its ability to produce unlimited energy. Among the renewable energies are the oceanic ones, which depend on the resources of the tidal waters and the oceans. Tides are a promising energy source, given their periodicity and predictability, using techniques of harmonic analysis or ocean modeling. The Amazon is a region with multiple sparsely distributed populations, with difficult access to energy. Renewable sources are an alternative to bring energy and development to these communities. This paper focuses on the assessment of the power of tidal currents in the Pará River Estuary (PRE, Brazilian Amazon) as an alternative source of electricity generation in the region. This estuary is characterized by particularities such as not having its own source, it has an extension of 300 km and a depth between 0 and 70 m. The methodology was based on the two-dimensional hydrodynamic model (2DH) of SisBahia. The results show the occurrence of five areas with potential for tidal energy exploitation. Power densities for these areas are in the range of 0.4–0.7 MWh/m² in a spring and neap tidal cycle. This article demonstrates the relevance of choosing parameterized quantities that do not depend on specific equipment, as well as the importance of an adequate characterization of the hydrodynamic patterns in the PRE, necessary to optimize the use of hydrokinetic energy.

Green economy has become the world's main goal of economic development in the twenty-first century. The new energy vehicle industry has developed rapidly in a green and low-carbon economy. The government has used subsidies to promote the healthy and efficient development of the new energy vehicle industry in its early development stage. However, due to information asymmetry and the correlation of interests between the government and firms, some new energy vehicle firms have fraudulent behavior to obtain government subsidies. In the face of this fraudulent phenomenon, how should the audit department take corresponding measures to avoid the audit risk of government subsidies for firms, and how can the government face the unknown nature of the development of the emerging industry? The study takes Suzhou Golden Dragon, a new energy automobile firm, as an example to analyze the impact of government subsidies on this automobile firm in recent years and explore the causes of its audit risk and corresponding countermeasures by analyzing the motive and means of its fraudulent behavior, which can play a role in improving the defects of China's government subsidy audit theory and strengthening the rigor of audit practice. By analyzing the fraudulent phenomenon, some reasonable suggestions can be given to the government to promote the healthy and benign development of China's new energy vehicle industry, which can also enrich the means of supporting the development of new industries in the early stage of the future.

In the modern era, every country work towards sustainable development with the help of effective utilization of renewable energy system. The design and planning of multi-renewable energy system networks for Hurawalhi, Maldives, with an approximate 450.09 KW load, is proposed in this study. The first resource assessment for solar radiation, wind velocity, and the tidal range is done through linear regression and decision tree-based data analysis. Design of the system is done through the HOMER software, where the electricity production (KWh/Year) through the solar and tidal systems are 1,401,086 and 197,509, respectively. The energy generation through the proposed system is 1593.6 kWh/day (Baseline) and 2424.25 (Scaled). Cost optimization is done through the Chaotic Particle Swarm Optimization and Cuckoo Optimization techniques. Further survival measurement is done through the logrank and probit analysis.

In the present scenario of renewable energy, there is growing interest in harnessing tidal energy resources in India. Converting the energy through the tidal range into electricity has the advantages of being predictable, yet the tidal range resources of India is largely unquantified. This paper shows possible tidal energy resources at Gulf of Kutch and Gulf of Khambhat. A detailed analysis to be done through the Logistic Regression, Linear Discriminant Analysis, K-Nearest Neighbor, Naïve Bayes, Support Vector Machine. Regression analysis is used to create the relationship between power generation and tidal range for different basin areas of different location. Other methods are used for the to identify the accuracy and validation of the results. In this paper the five potential locations of Gulf of Kutch are Okha, Sikka, Rozi, Kandla and Navlakhi, on the other hand five potential locations of Gulf of Khambhat are Daman, Hazira, Bhavnagar, Pipavav and Diu. In this analysis also identify possible power generation at all the location with probable basin areas. The possible basin areas at all the locations are 5 × 10⁶ m², 7 × 10⁶ m², 10×10⁶ m², 12×10⁶ m². It is find out, in the Gulf of Kutch the maximum tidal range at Okha, Sikka, Rozi, Kandla and Navlakhi are 8.88 m, 9.41 m, 7.97 m, 8.88 m and 8.07 m respectively. In the gulf of Khambhat the maximum tidal range at Daman, Hazira, Bhavnagar, Pipavav and Diu are 8.96 m, 13.14 m, 13.33 m, 13.41 m and 11.56 m respectively.

This work describes the methodology used to realize a performance analysis of an ammonia-water condensing gas absorption heat pump. This heat pump shows a nominal heating output of 18,9 kW for an outdoor temperature of 7 °C and a delivery temperature of 35 °C, and it is designed for domestic hot water and heating production. The experimental results obtained in the laboratory are contrasted with those obtained from the monitoring of two residential facilities in the northern part of Belgium. Experimental tests were carried out in a climatic chamber to emulate different outdoor climatic conditions based on a combination of the EN 12309 requirements and typical Belgium weather data. Measurements of gas consumption, electrical consumption, water flows, and temperatures were collected to compute performance indicators. On the other hand, the monitoring data was analyzed and contrasted with the experimental results to evaluate the field systems’ performance; the problems found and modifications made are described and discussed. The results show that the performance of the systems is highly dependent on the coupling with other appliances, on the operating conditions and control of the system, resulting in penalties that can be considerable depending on the configuration used. An empirical model calibrated with experimental data is proposed, as well as a penalization factor calibrated with the monitoring data. The results presented evidence the differences found between the studied facilities, highlighting the main role of proper installation and control not to diminish the main performance indicators.

Activation of heat pump flexibilities is a viable solution to support balancing the grid via Demand Side Management measures and fulfill the need for flexibility options. Aggregators as interface between prosumers, distribution system operators and balance responsible parties face the challenge due to data privacy and technical restrictions to transform prosumer information into aggregated available flexibility to enable trading thereof. Thereby, literature lacks a generic, applicable and widely accepted flexibility estimation method for heat pumps, which incorporates reduced sensor and system information, system- and demand-dependent behaviour. In this paper, we adapt and extend a method from literature, by incorporating domain knowledge to overcome reduced sensor and system information. We apply data of five real-world heat pump systems, distinguish operation modes, estimate power and energy flexibility of each single heat pump system, proof transferability of the method, and aggregate the flexibilities available to showcase a small HP pool as a proof of concept.

Studies focusing on reducing trade-related carbon footprint by consolidating institutional quality are not much in the literature. This study examines the role of institutional quality and green trade on carbon emissions. The empirical findings are based on generalised method of moments and 45 African countries spanning the period of 2008 to 2020. The initial findings revealed that institutional quality has a neutral impact on carbon emissions but trade openness increases it. However, strengthening institutional quality towards green trade reduces carbon emissions. Precisely, strengthening institutional quality towards green trade by 1% will have a joint effect of reducing carbon emissions by 0.04%. The policy implication is that clean trade can be achieved by strengthening the region's institutions which subsequently promote environmental sustainability.

Methane emission modelling is essential for predicting landfill gas emissions and recovery, including sizing the landfill gas collection system. This study presents a developed methane emission model which can be replicated globally. The steps of model development and model equation are highlighted. The output from the developed model shows an average methane generation rate of around 8.06 m³/h in 1997 to about 16.17 m³/h in 2021. The results of the developed model have been critically addressed, and a comparison of the output is discussed with other models. The simulation done using the Monte Carlo approach shows a maximum deviation of around 18% from the developed model, validating the accuracy of the developed model. The findings of this study will serve as the basis for the development of a more robust LFG model for Indian as well as global landfills for methane recovery.

This paper investigates the operation and control of smart inverters (SI) for solar and solar-plus-storage systems with an emphasis on Volt-VAR Control (VVC) at solar interconnections. The paper provides techno-economic recommendations for both normal-size and oversized solar inverters equipped with VVC. The objective is to minimize the voltage violations, and active power curtailment by providing reactive power support to the grid while the IEEE 1547-2018 standards are satisfied. Moreover, a collaborative VVC is tested where a battery storage system is paired with the solar facility which is becoming a popular configuration to enhance energy resilience in communities. An unbalanced distribution network is modeled based on a modified IEEE 13-bus system to which three 700 kW solar PV plants are connected through smart inverters. Solar data from the University of Louisiana’s 1.1 MW solar farm is used and grouped into 28 clusters. Those clusters represent a 2-year period with 15-min granularity. Typhoon HIL 402 real-time simulator is utilized for modeling and verifying the proposed approach. A control prototype is also developed on dSPACE MicroLabBox to further investigate the interaction between the controller and the rest of the system in a more realistic testing environment.