Tag Archives: renewable energy

1734-1746 I. Dunmade
Community/shared solar power option: a pathway to sustainable rural electrification in Nigeria
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Community/shared solar power option: a pathway to sustainable rural electrification in Nigeria

I. Dunmade*

Mount Royal University, Faculty of Science & Technology, Department of Earth & Environmental Sciences, 4825 Mount Royal Gate SW, Calgary, AB T3K 0C3, Canada
*Correspondence: idunmade@mtroyal.ca, israel_dunmade@yahoo.ca

Abstract:

Nigerian governments at all levels have been making concerted effort to extend electricity supply to the rural areas. Among the several efforts by various governments are formulation of rural electrification policies, creation of agencies for the administration of rural electrification projects, installation of diesel power generators, and development of public-private partnership strategies in solving rural power supply problems. While significant progress has been made, several rural communities are yet to have access to electricity supply. Rugged terrain and limited financial resources are among the constraints to extension off-grid to the rural areas. However, electricity supply, being one of the drivers of economic development and social well-being, is a problem that has to be tackled head-on. The current climate change concern and many other environmental issues of our time necessitate finding a sustainable solution to the problem. Consequently the goal of this study was to examine the potentials of community solar power option as a sustainable rural electrification approach in Nigeria. Other goals included identifying potential hick-ups and solutions to lifecycle management of community solar. Moreover, the study was to determine the suitable configuration for efficient and sustainable community solar power management in Nigeria. The study methodology involved intensive literature survey, historical data collection and case studies on rural electrification in Nigeria as well as examples of community solar projects in Nigeria. Preliminary results revealed that community solar power would be a sustainable approach to rural electrification in Nigeria if a number of conditions are satisfied. Some of the conditions to be satisfied include devolving the management of a community solar system to a participative committee of stakeholders representatives, and incorporating community capacity building in the plan. Other conditions are government, corporate and municipalities’ collaboration in funding such projects from scratch till after one or two years of operation, and incorporation of monitoring and intervention strategies for continuous power supply and further improvement.

Key words:

community solar, lifecycle management, renewable energy, rural electrification, shared solar, sustainable energy

177–182 V.A. Mazur, H.V. Pantsyreva, K.V. Mazur, R.O. Myalkovsky and O.O. Alekseev
Agroecological prospects of using corn hybrids for biogas production
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Agroecological prospects of using corn hybrids for biogas production

V.A. Mazur¹, H.V. Pantsyreva¹*, K.V. Mazur¹, R.O. Myalkovsky² and O.O. Alekseev¹

¹Vinnytsia National Agrarian University, 3, Soniachna Str., UA21008 Vinnytsia, Ukraine
²State Agrarian and Engineering University, 13, Shevchenko Str., UA32300 Kamianets-Podilskyi, Ukraine
*Correspondence: pantsyreva@vsau.vin.ua

Abstract:

Ukraine is an agricultural country with great agricultural potential for biogas production, which is the key to fertile soils and favorable climatic conditions for energy crops, including corn. The article analyzes the experience of using biogas in Ukraine and the world, its mechanism of production. The leader in biogas production in the world is the European Union in general and Germany in particular. The total number of biogas plants in Europe exceeds 11 thousand, of which 7.2 thousand in Germany. Іnstalled biogas, which is released in the process of complex fermentation of organic waste, consists of a mixture of gases: methane – 55–75%, carbon dioxide – 23–33%, hydrogen sulfide – 7%. An important sector of renewable energy sources in biogas production is presented and the prospects for its use are determined. The energy dependence of our country on the volumes of imported natural gas is analyzed. The main aspects of biogas production are explored using renewable energy sources that are inexhaustible in our crane and the phased operation of the biogas plant is investigated. The real advantages of the need for biogas production and use in our country are outlined. Problems aimed at the development of alternative energy have been proved in order to detect environmental pollution. It has been established that in Ukraine the use of corn silage to improve the efficiency of biogas production at existing biogas stations has not been used so far. The problems of increasing the yield of corn plants have been proved not only by breeding and genetic methods, but also by cultivation technology.

Key words:

biogas, corn, pollution, renewable energy, the intensification of production

771–782 M. Nurmet, M. Mõtte, K. Lemsalu and J. Lehtsaar
Bioenergy in agricultural companies: financial performance assessment
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Bioenergy in agricultural companies: financial performance assessment

M. Nurmet¹²*, M. Mõtte¹, K. Lemsalu¹ and J. Lehtsaar¹

¹Estonian University of Life Sciences, Institute of Economics and Social Sciences, F. R. Kreutzwald street 1, EE51006 Tartu, Estonia
²University of Tartu, Faculty of Economics, Department of Accounting and Finance, J. Liiv street 4, EE50409 Tartu, Estonia
*Correspondence: maire.nurmet@emu.ee

Abstract:

The target of increasing the use of renewable energy in rural areas has initiated the investments in bioenergy. The purpose of this paper is to assess the financial performance of Estonian agricultural companies that have invested in bioenergy solutions. An investment in bioenergy is attractive to the company if the results obtained by it enable benefits to the investors. In the context of the study of financial performance of agricultural companies that have undertaken bioenergy investments, the key performance indicators based on DuPont identity are analysed from the perspective of formulating and implementing a company’s financial decisions. The data of financial statements of the analysed companies are from Estonian Agricultural Registers and Information Board (ARIB) and Commercial Register. The study reports the financial performance results of Estonian agricultural companies using renewable resources and producing bioenergy: whether they achieved higher efficiency and profitability or change in financial structure. The Estonian agricultural companies that have invested in bioenergy solutions may need to control their financial performance by improving profitability and controlling financial leverage.

Key words:

agricultural companies’ performance, bioenergy investment, DuPont identity, renewable energy

365-376 V. Chiteculo, A. Brunerová, P. Surový and M. Brožek
Management of Brazilian hardwood species (Jatoba and Garapa) wood waste biomass utilization for energy production purposes
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Management of Brazilian hardwood species (Jatoba and Garapa) wood waste biomass utilization for energy production purposes

V. Chiteculo¹*, A. Brunerová²*, P. Surový¹ and M. Brožek²

¹Czech University of Life Sciences Prague, Faculty of Forestry and Wood Sciences, Department of Forest management, Kamýcká 129, CZ165 00 Prague, Czech Republic
²Czech University of Life Sciences Prague, Faculty of Engineering, Department of Material Science and Manufacturing Technology, Kamýcká 129, CZ165 00 Prague, Czech Republic
*Correspondence: brunerova@tf.czu.cz; chiteculo@fld.czu.cz

Abstract:

In the Federative Republic of Brazil, Jatoba (Hymenaea courbaril) and Garapa (Apuleia leiocarpa) trees are intensively harvested. The yield of one log is approximately 45–55%, which indicates a great amount of produced wood waste biomass.Present research monitored the suitability of wood waste biomass from Jatoba and Garapa trees for bio–briquette for solid biofuel production. The research was focused on chemical parameters,and energy potential of such biomass kinds. Jatoba wood waste biomass was used for the production of bio–briquette fuel and its final mechanical quality was investigated by determination of their mechanical quality indicators. Results of chemical analysis (in wet basis) exhibited great level of ash content in case of both species (Jatoba – 0.31%, Garapa – 3.02%), as well as high level of energy potential; net calorific value equal to 18.92 MJ kg^–1 for Jatoba and to 18.395 MJ kg^–1 for Garapa. Analysis of elementary composition proved following levels of oxygen content: Jatoba – 41.10%, Garapa – 39.97%. Mechanical analysis proved bio–briquette samples volume density ρ equal to 896.34 kg m^–3 which indicated quality bio–briquette fuel, while the level of rupture force RF occurred at a lower level – 47.05 N mm^–1. Most important quality indicator, the mechanical durability DU, unfortunately, occurred at a lower level; DU = 77.6% compared to the minimal level of bio–briquette fuels intended for commercial sales which must be > 90%. Overall analysis proved materials suitability for energy generation purpose with certain limitations which can improve by changing production parameters of briquetting.

Key words:

briquetting, direct combustion, renewable energy, waste management

656-668 A. Brunerová, H. Roubík, M. Brožek and J. Velebil
Agricultural residues in Indonesia and Vietnam and their potential for direct combustion: with a focus on fruit processing and plantation crops
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Agricultural residues in Indonesia and Vietnam and their potential for direct combustion: with a focus on fruit processing and plantation crops

A. Brunerová¹*, H. Roubík², M. Brožek¹ and J. Velebil³

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department of Material Science and Manufacturing Technology, Kamýcká 129, CZ165 00 Prague, Czech Republic
²Czech University of Life Sciences Prague, Faculty of Tropical AgriSciences, Department of Sustainable Technologies, Kamýcká 129, CZ165 00 Prague, Czech Republic
³Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ165 00 Prague, Czech Republic
*Correspondence: brunerova@tf.czu.cz

Abstract:

Energy consumption in Indonesia and Vietnam has grown rapidly in recent decades. To meet the energy needs of both countries, a higher utilisation of waste biomass sources may represent an adequate solution. Investigated samples represent major crop residues (waste biomass) originating mainly from the agriculture sector of the selected countries. Herbaceous waste biomass from Indonesia is, namely, cassava stems and root peelings (Manihot esculenta), coffee leaves (Coffea arabica), cacao leaves (Theobroma cacao), banana leaves (Musa acuminata), bamboo leaves (Bambusoideae spp.) and aloe vera leaves (Aloe vera). Furthermore, fruit and aquatic waste biomass originating from Vietnam is, specifically, sugarcane bagasse (Saccharum officinarum), durian peelings (Durio zibethinus), rambutan peelings (Nephelium lappaceum), banana peelings (Musa acuminata), water milfoil (Myriophyllum spicatum) and water hyacinth (Eichhornia crassipes). All mentioned types of waste biomass were subjected to proximate and calorimetric analysis: moisture, ash and volatile matter contents (%) and higher and lower heating values (MJ kg^–1). Obtained values indicated the highest level of ash content in fruit biomass samples in the case of sugarcane bagasse (0.84%), in herbaceous biomass in the case of cassava stems (3.14%) and in aquatic biomass in the case of water hyacinth (14.16%). The highest levels of lower heating values were achieved by following samples (best samples from each biomass type): cassava stems (17.5 MJ kg^–1); banana peelings (17.3 MJ kg^–1) and water hyacinth (12.8 MJ kg^–1). The overall evaluation of all observed samples indicated that the best suitability for energy utilisation by direct combustion of investigated representatives is fruit waste biomass, followed by herbaceous waste biomass and then aquatic waste biomass.

Key words:

biological residues, calorific value, energy potential, renewable energy, waste biomass, waste management

1247-1256 K. Sirviö, S. Niemi, R. Help, S. Heikkilä and E. Hiltunen
Kinematic viscosity studies for medium-speed CI engine fuel blends
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Kinematic viscosity studies for medium-speed CI engine fuel blends

K. Sirviö*, S. Niemi, R. Help, S. Heikkilä and E. Hiltunen

University of Vaasa, Faculty of Technology, PL 700, FIN-65101 Vaasa, Finland
*Correspondence: katriina.sirvio@uva.fi

Abstract:

Engine-driven power plants, run by diesel fuel or gas, will be needed for peaking power to keep the electricity grids stable when the production of renewable electricity, e.g. utilizing wind or solar power, is increased.
The choice of the alternative, renewable fuels for engine-driven power plants and marine applications is at the moment quite narrow. The amount of renewables of all liquid fuels is at present less than 2%. Biodiesels, FAMEs, have been studied for long time and apparently, despite of the problems they may have, they are still in the great interest. One important increment to the category of alternatives is fuels that are produced from e.g. oil wastes, i.e., recycled fuels. They are not renewable, but recycling of potential energy raw materials is still one step forward in increasing the suitable and more sustainable options.
To utilize the blends in medium-speed engines for power production, accurate knowledge of the physical and chemical properties of fuel blends is very important for the optimization of engine performance. The determination of the fuel kinematic viscosity is needed to create proper fuel atomisation. The injection viscosity affects directly the combustion efficiency and the engine power. Consequently, this study focused on measuring kinematic viscosity curves for seven fuel blends, as well as the neat fuels used for blending. The temperature range was 10–90 °C. The fuels used for blending were rapeseed methyl ester, animal-fat based methyl ester, hydro-treated vegetable oil, light fuel oil and marine gas oil produced from recycled lubricating oils.

Key words:

alternative fuels, fuel blends, Fuel viscosity, power plant, renewable energy, viscosity curve

344–358 A. Brunerová, M. Brožek and M. Müller
Utilization of waste biomass from post–harvest lines in the form of briquettes for energy production
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Utilization of waste biomass from post–harvest lines in the form of briquettes for energy production

A. Brunerová*, M. Brožek and M. Müller

Czech University of Life Sciences Prague, Faculty of Engineering, Department of Material Science and anufacturing Technology, Kamýcká 129, CZ165 00 Prague, Czech Republic *Correspondence:brunerova@tf.czu.cz

Abstract:

A great amount of herbal waste biomass is produced nowadays during agriculture crop processing; also during ‘post–harvest lines’ operations. Such waste biomass occurs in the bulk form, thus, is not suitable for direct combustion; it can be improved by using of briquetting technology. Therefore, present paper provides chemical, mechanical and microscopic analyses of waste biomass originating from post–harvest lines and briquettes produced from it. Namely, waste biomass originated from production of oat (Avena sativa) – husks, wheat (Triticum spp.) – husks and poppy (Papaver somniferum) – straw and seed pods and mixture of all mentioned were investigated. Unprocessed materials were subjected to microscopic and chemical analysis and subsequently produced briquette samples were subjected to determination of its mechanical quality. A satisfactory level of moisture and ash content was observed, as well as, materials energy potential; oat – 17.39 MJ kg^-1, wheat – 17.04 MJ kg^-1, poppy – 14.48 MJ kg^-1. Also microscopic analysis proved suitability of all feedstock materials within evaluation of geometrical shapes of their particles. However, evaluation of briquette mechanical quality unsatisfactory results. Process of briquetting revealed unsuitability of oat feedstock for briquette production; other materials proved following values of volume density and mechanical durability (in sequence): wheat – 1,023.19 kg m^-3, 89.1%; poppy – 1,141.43 kg m^-3, 94.7%; mixture – 972.49 kg m^-3, 62.7%. In general, only poppy briquettes achieved requested mechanical quality level for commercial briquette production. However, undeniable advantage of investigated materials is the form they occurred in; no further feedstock preparation (drying, crushing) was needed.

Key words:

calorific value, cereal husk, mechanical durability, renewable energy, solid biofuels

456–467 M. Križan, K. Krištof, M. Angelovič and J. Jobbágy
The use of maize stalks for energy purposes and emissions measurement during their combustion
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The use of maize stalks for energy purposes and emissions measurement during their combustion

M. Križan, K. Krištof*, M. Angelovič and J. Jobbágy

University of Agriculture in Nitra, Faculty of Engineering, Department of Machines and Production Biosystems, Tr. A. Hlinku 2, SK949 76 Nitra, Slovakia
*Correspondence: koloman.kristof@uniag.sk

Abstract:

Biomass is an ideal renewable energy with advantages of abundance resources and neutral in greenhouse gas circulation. Majority of this energy could have been used directly in agriculture itself. The rest of the biomass for other parts of industry or even communal parts could be made available as a refined and densified biomass available for direct combustion in form of bales. The objective of the work was a monitoring of possibilities of maize cortical use for energy purposes during combustion. Emissions measurement from the combustion of maize phytomass was performed by measuring device TESTO 350 M/XL. During the combustion of packages with the moisture of 18% and 38% was monitored and the effect of moisture on the content of gas emissions of CO, CO2, NO, NO2 as well as the percentage of residual O2 in the flue gas after combustion. All values of monitored emission limits were in current normative limits defined in Collection of Laws no. 356/2010. All emissions limits are in accordance to monitored standards for CO, CO2, NO, NO2, but on the other hand it should be noted that the more favourable results are based on combustion of cortical with moisture of 18% than at 38%. The issue of maize cortical harvesting considering machinery, technological and economical viewpoint within the Slovak republic but also worldwide is poorly understood and therefore these issues should be the subject of further research.

Key words:

emission limits, maize cortical, maize cortical combustion, maize cortical harvesting, renewable energy

1101–1106 A. Mäkiranta, B. Martinkauppi and E. Hiltunen
Seabed sediment – a natural seasonal heat storage feasibility study
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Seabed sediment – a natural seasonal heat storage feasibility study

A. Mäkiranta*, B. Martinkauppi and E. Hiltunen

University of Vaasa, Faculty of Technology, Electrical Engineering and Energy Technology, P.O. Box 700, FI-65101 Vaasa, Finland
*Correspondence: anne.makiranta@uva.fi

Abstract:

The new discovery among renewable energy resources, seabed sediment, has been utilised as a heat source for 42 houses in Vaasa since 2008. Sediment heat is annually loaded by the Sun. In this study the amount of annually charged energy is estimated. The difference of sediment temperatures between the coldest and the warmest month during the year is a key value in the approximation of the loaded energy. Sediment temperatures are measured once per month via optical cable by distributed temperature sensing (DTS) method. The monitoring period is three years, 2014–2016. The estimation of incoming energy (575 MWh) versus known exploited energy (560 MWh) is reasonable. Despite of the extraction this seasonal heat storage in the seabed of the Baltic Sea seems to reload well annually.

Key words:

distributed temperature sensing, heat storage, renewable energy, sediment heat

359–368 A. Brunerová, J. Malaťák, M. Müller, P. Valášek and H. Roubík
Tropical waste biomass potential for solid biofuels production
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Tropical waste biomass potential for solid biofuels production

A. Brunerová¹*, J. Malaťák², M. Müller¹, P. Valášek¹ and H. Roubík³

¹Czech University of Life Sciences Prague, Faculty of Engineering, Department of Material Science and Manufacturing Technology, Kamýcká 129, CZ165 00 Prague, Czech Republic
²Czech University of Life Sciences Prague, Faculty of Engineering, Department of Technological Equipment of Buildings, Kamýcká 129, CZ165 00 Prague, Czech Republic
³Czech University of Life Sciences Prague, Faculty of Tropical AgriSciences, Department of Sustainable Technologies, Kamýcká 129, CZ165 00 Prague, Czech Republic
*Correspondence: brunerova@tf.czu.cz

Abstract:

Subsequent utilization of waste biomass in developing countries occurs at poor level, despite the act, that it has great potential in solid biofuel production. Densified waste biomass is utilized for direct combustion, therefore, its suitability (energy potential, chemical composition) must be determined in attempt to protect environment and reduce air pollution. Main aim of present research was to determine suitability of waste biomass originating from production of rice (Oryza sativa), Date fruit (Phoenix dactylifera L.) and Jatropha fruit (Jatropha curcas) for solid biofuel production. Within a moisture, ash and volatile matter contents, major chemical elements (C, H, N, O) and net calorific value (NCV) were determined. Rice waste analysis proved low NCV (14.33 MJ kg^–1) and high ash content (20.74%), which presented problems during combustion. Jatropha fruit waste (cake) analyses exhibited outstanding NCV (24.44 MJ kg^–1) caused by residual oil content. Within major elements analysis a low content of oxygen (26.61%) was proved (recommended). Date fruit waste exhibited average NCV (16.40 MJ kg^–1). However, high oxygen content (44.01%) was defined as limiting factor. Overall evaluation proved greatest suitability for Jatropha fruit waste (cake), followed by Date fruit waste and lowest potential was determined for Rice waste. However, investigated plants are not cultivated for energy production purposes, thus, observed results achieved satisfactory level of their suitability for solid biofuel production.

Key words:

briquettes, calorific value, Jatropha curcas, renewable energy, rice husk