scholarly journals Innovative Designs in Household Biogas Digester in Built Neighbourhoods

2021 ◽  
Author(s):  
Isaac Mbir Bryant ◽  
Martha Osei-Marfo

Most household biogas digesters operate on continuous automatic stirring modes. Often, these digesters rely on electrical energy for their continuous operations which are often mesophilic. Rarely do manually-stirred discontinuous household biogas digesters operating on hyper-thermophilic conditions exist. This work seeks to highlight some innovative designs in a household biogas digester piloted in Terterkessim slum in the K.E.E.A. Municipality of the Central Region, Ghana. A pyramidal dome-shape biogas digester was constructed on an abandoned septic tank using blocks and concrete. The digester has a rectangular sub-surface base and a pyramidal gas holder above the surface of the soil. The digester has a two-blade manual stirrer, a ball bearing affixed at the bottom and a handle to manually mix the content of the digester. In order to heat the content of the digester to a hyper-thermophilic condition for hygienising the digestate, a solar-photovoltaic was installed on the roof of a toilet connected to the household biogas digester.

2021 ◽  
Vol 3 (5) ◽  
Author(s):  
Arvind Sharma ◽  
Mohan Kolhe ◽  
Alkistis Kontou ◽  
Dimitrios Lagos ◽  
Panos Kotsampopoulos

Abstract In this paper, solar photovoltaic hosting capacity within the electrical distribution network is estimated for different buses, and the impacts of high PV penetration are evaluated using power hardware-in-loop testing methods. It is observed that the considered operational constraints (i.e. voltage and loadings) and their operational limits have a significant impact on the hosting capacity results. However, with increasing photovoltaic penetration, some of the network buses reach maximum hosting capacity, which affects the network operation (e.g. bus voltages, line loading). The results show that even distributing the maximum hosting capacity among different buses can increase the bus voltage rise to 9%. To maintain the network bus voltages within acceptable limits, reactive power voltage-based droop control is implemented in the photovoltaic conditioning devices to test the dynamics of the network operation. The results show that implementation of the droop control technique can reduce the maximum voltage rise from 9% to 4% in the considered case. This paper also presents the impact of forming a mesh type network (i.e. from radial network) on the voltage profile during PV penetration, and a comparative analysis of the operational performance of a mesh type and radial type electrical network is performed. It is observed that the cumulative effect of forming a mesh type network along with a droop control strategy can further improve the voltage profile and contribute to increase photovoltaic penetration. The results are verified using an experimental setup of digital real-time simulator and power hardware-in-loop test methods. The results from this work will be useful for estimating the appropriate photovoltaic hosting capacity within a distribution network and implementation of a droop control strategy in power conditioning devices to maintain the network operational parameters within the specified limits. Highlights Voltage and line loading constraints’ combination can reduce PV hosting capacity by 50% as compared to only voltage as a constraint. Implementation of reactive power versus voltage droop control in PV power conditioning device can reduce voltage variation from 9% to 4%. In a PV integrated electrical energy network, line loading can be reduced by 20% if the network is configured from radial to mesh type.


2014 ◽  
Vol 675-677 ◽  
pp. 1880-1886 ◽  
Author(s):  
Pedro D. Silva ◽  
Pedro Dinis Gaspar ◽  
J. Nunes ◽  
L.P.A Andrade

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 belonging to the following agrifood sectors: meat, dairy, horticultural, distribution and wine. Through the quantification of energy consumption of companies is possible to determine the amount of greenhouse gases (GHGs) emissions indexed to its manufacturing process. Comparing the energy and GHGs emissions indexes of companies of a sector and between sectors is possible to create reference levels. With the results of this work is possible to rating the companies in relation to reference levels of energy and GHGs emissions and thus promote the rational use of energy by the application of practice measures for the improvement of the energy efficiency and the reduction of GHGs emissions.


The solar energy being clean, green & commercially modest, have become one of the most prevalent choice amongst the renewable sources of electrical energy. Utilization of energy generated from Solar photovoltaic (SPV) system rest on the maximum extraction of the power generated. Ideal maximum power point (MPP) tracking (MPPT) is used to transfer 100% generated power from source and transfer it to load. In literature of recent years, a good number of publications found on SPV systems and MPPT. In this paper most popular MPPT techniquesPerturb & Observe (PO) and Incremental Conductance (IC) methods are simulated and implemented. The comparison is also presented on the ground of parameters like tracking time, tracking efficiency etc.


Energies ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2701 ◽  
Author(s):  
Saeed Abdul-Ganiyu ◽  
David A Quansah ◽  
Emmanuel W Ramde ◽  
Razak Seidu ◽  
Muyiwa S. Adaramola

The main objective of this paper is to experimentally assess the real-life outdoor performance of a photovoltaic-thermal (PVT) module against a conventional photovoltaic (PV) system in a hot humid tropical climate in Ghana. An experimental setup comprising a water-based mono-crystalline silicon PVT and an ordinary mono-crystalline silicon PV was installed on a rooftop at the Kwame Nkrumah University of Science and Technology in Kumasi and results evaluated for the entire year of 2019. It was observed that the annual total output energy of PV module was 194.79 kWh/m2 whereas that of the PVT for electrical and thermal outputs were 149.92 kWh/m2 and 1087.79 kWh/m2, respectively. The yearly average daily electrical energy yield for the PV and PVT were 3.21 kWh/kWp/day and 2.72 kWh/kWp/day, respectively. The annual performance ratios for the PV and PVT (based on electrical energy output only) were 79.2% and 51.6%, respectively, whilst their capacity factors were, respectively, 13.4% and 11.3%. Whereas the highest monthly mean efficiency recorded for the PV was 12.7%, the highest combined measured monthly mean electrical/thermal efficiency of the PVT was 56.1%. It is also concluded that the PVT is a worthy prospective alternative energy source in off-grid situations.


Author(s):  
Gary M. Sandquist ◽  
Jay F. Kunze

Perception that U.S. government energy subsidies have favored nuclear energy at expense of renewables (hydroelectric, wind, solar, geothermal) is not supported by facts. Largest beneficiaries between 1950 and 2006 from federal energy subsidies have been oil and gas receiving more than half of all federal incentives. Primary subsidy for nuclear energy has been R&D. Evaluating the actual electrical energy produced resulting from government subsidy support shows that wind and solar have cost taxpayers 355mils/kWh, coal 1.53 mils/kWh, nuclear 3.8 mils/kWh and hydro at 5.88 mils/kWh. Average cost of U.S. electrical energy in 2006 was 91 mils/kWh so renewables were subsidized at four times the average cost of electricity. Subsidy for Solar Photovoltaic to produce 0.01% of U.S. electricity as of 2006 was $4.43/kWh.


2014 ◽  
Vol 590 ◽  
pp. 878-882 ◽  
Author(s):  
P.D. Gaspar ◽  
P.D. Silva ◽  
J. Nunes ◽  
L.P. Andrade

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.


2021 ◽  
Vol 335 ◽  
pp. 03002
Author(s):  
Chong Jia Joon ◽  
Kelvin Chew Wai Jin

Solar photovoltaic (PV) panels have been widely used to convert the renewable energy from the sun to electrical energy to power electrical loads but suffers from relatively low efficiency between 15% to 22%. Typically, the panels have an average lifespan of 25 to 30 years but could degrade quicker due to the panel overheating. Beyond the optimum working temperature of 25°C, a drop of efficiency by 0.4 to 0.5% for every 1°C had been reported. For solar PV applications in urban regions, passive cooling is beneficial due to limited amount of space and lower energy consumption compared to active cooling. A solar PV system with augmented cooling was conducted at a balcony of a condominium from 10am until 2pm. The solar PV system consisted of an Arduino controller, solar panel module, temperature sensor and LCD monitor. Reusable cold and hot gel packs were attached to the bottom of the solar PV. Both setups of solar PV panel with and without the cooling system were placed at the balcony simultaneously for measurement of temperature, output voltage and current. From this research, the outcome of implementing a cooling system to the solar PV increases the efficiency of the energy conversion.


2021 ◽  
Vol 302 ◽  
pp. 01006
Author(s):  
Sukkhi Buakaew ◽  
Prayut Jiamrittiwong ◽  
Nutdechatorn Puangngernmak

Renewable energy as a solar photovoltaic system represents an essential role in improving and promoting energy sustainability in agricultural/aquaculture-related activities. The “Crab Bank” is the program on practicing the caught gravid females of Blue Swimming Crab (BSC) in supporting conditions, allowing them to spawn and then release the zoea and young crabs back to the sea where are in the Eastern Economic Corridor (EEC). Onward with the project, many scientific studies assess the BSC stocks condition, evaluate the fishing habitat, and other relevant issues as the energy used in a micro-indoor system as Recirculating Aquaculture Systems (RAS). The off-grid solar photovoltaic system is used in the system cause the installed location was near the seaside area. The system’s large size was operating, including solar panels, inverter, charger, and batteries to maintain the AC motor pump, affecting much energy loss in the system. The off-grid solar system design for modular systems is represented in this paper to describe the new structure of the micro modular RAS that reduces cost and increases the solar system’s efficiency in modular concepts comparing the traditional system. The new structure model represents the calculation result in the term of electrical energy and experiment to scale for replacement in the aquaculture area in Rayong or Jantaburi in the EEC region. This research is a cooperation between KMUTNB Rayong and the Provincial Energy Office Of Rayong.


2015 ◽  
Vol 813-814 ◽  
pp. 992-996
Author(s):  
P. Chandra Dheeraj ◽  
B. Avinash ◽  
G. Sai Pavan Kumar ◽  
P.S. Sivasakthivel ◽  
M. Venkatesan

With the fast depletion of the conventional energy resources and the amount of pollution it is creating, the entire world is looking for an alternative non-conventional and a renewable energy to lessen the dependency on the conventional energy resources. In this scenario, utilizing solar energy which is abundant in nature is gaining high attention. One way of utilizing solar energy is by using solar photovoltaic cells which convert light energy into electrical energy, but they are too costly and less efficient. Many techniques are being developed to reduce the cost and improve the efficiency in harnessing solar energy. Sun tracking technique is one of the methods to increase the efficiency of solar cells. The present work is focused on providing a microcontroller based automatic two-axis sun tracker using Photodiodes as sensors to track sun. The system is assisted with a manual control through LabVIEW (Graphical User friendly Interface) to aid during bad weather conditions.


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