Photo: HA Hessen Agentur GmbH –Jan Michael Hosan
The market for solid fuels, especially renewable solid fuels, is growing. To meet the demands, so far unused biomass from agriculture and forestry is targeted for utilisation. Carbonisation of those kinds of biomass opens up new strategies in regional material flow management. For this purpose, a project investigated the production and monitored the combustion properties of briquettes for small heating systems with and without biochar (carbonised biomass).
impact on a flame at the height of the stove and being high enough to capture all emissions. Fire power, fire temperature and thermal efficiency were found not to be affected by the hood extraction rates. Sulphur dioxide and total suspended particles showed no significant effect of extraction at a 95% confidence level while a mea- surable influence of extraction on carbon monoxide emissions was detected, but this was considerably smaller than the effect of the stove. There was no detectable interaction between stove type and extraction level indicat- ing that the influence of the extraction on emissions is independent of the type of stove. The authors concluded that, provided the extraction level does not change between tests and falls between their tested boundaries, it is possible to use an extraction hood to compare emissions from different stoves. Table 10 summarizes pollutant emission factor monitoring studies from biomass gasification. From these studies it can be inferred that biomass must be gasified under optimized conditions to minimize these emission factors. It is feasible that comparisons between emissions from different cooking devices may be made without the aid of air-flow measurements the- reby significantly simplifying and reducing the cost of emission assessment in the stove design. For the hood design methodology,  proposed a hood which was described in details by . The tower is in the form of an inverted funnel with a cylindrical bottom, 1.0 m in diameter and 1.9 m high. From the top of the cylinder, the tower decreases to 0.2 m in a length of 1.0 m and is topped with a stack 1.2 m in height. This design has the po- tential to vent out the flue gases at turbulent flows because of the decreasing diameter of the inlet and outlet.
most operations. There is therefore a need for a cost-effective energy supply system in the smallscale sector.
This study is based on a sandstone operation in Phuthadithjaba, Free State Province. Like most SSM operations, energy requirement for Maluti Sandstone was low. This is because the operation is largely labour intensive, with electricity only used during processing stages. The operation is located in an area that receives good sunshine, and hence solar was used for the assessment. Although South Africa is rated amongst the countries with diverse rich renewable energy resources, the use of renewable energy is area-specific. It is therefore important to locate potential RE resource (s) in a given area. Based on the findings, it was concluded that the integration of energy systems (i.e. solar and generator) seems feasible as compared to stand-alone systems. Generators remain cheap in terms of start-up capital; however their long-term costs are high. Hybrid systems not only offer an affordable option, but also eliminate disadvantages of different systems thereby ensuring reliability and security of supply. It is clear that renewable technologies are becoming favourable and attractive solutions because of their long-term benefits as compared to traditional sources.
Package System - SorTech
Cooling and Heating
Adsorption Chillers with 8 or 15 kW cooling capacity
SorTech AG develops, manufactures and distributes adsorption chillers in the smallscale performance range. The chillers are compact, highly efficient and noiseless. The electricity consumption of an ACS 08 is only 7 W – this is unmatched worldwide. Driving temperature as low as 55°C is sufficient to drive the chillers. That’s why SorTech chillers are a perfect match for solar-driven cooling. Furthermore, the machines can also be used for heating assistance with the integrated heat pump mode.
Designers might chose hydraulics for tiny, mobile powered systems because the same power density advantage of hydraulics over electromechanical should hold for a powered orthosis as it holds for an excavator. The story, however, is complex because the scaling laws are not intuitive. For example, in a cylinder, force is proportional to area while weight is proportional to volume. Surface effects such as friction drag of seals and viscous drag of gaps become significant at small bores and impact overall efficiency. On the other hand, the thickness, and thus the weight, of a cylinder wall required to contain a fixed pressure goes down with bore. The final weight of a hydraulic system at smallscale cannot be determined by proportionally scaling the weight of a large system and determining for equal efficiency, which is lighter a fluid power or an electromechanical system for a tiny system cannot be answered using intuition.
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The C-Series controller can operate as a Diversion Controller, also called a shunt regulator, to manage battery charging from alternative energy sources such as PV, wind or hydroelectricgenerators. A diversion controller monitors battery voltage and, when the voltage exceeds the settings for your charge stage (whether bulk or float), the power is diverted from the source (solar, wind, or hydro generator) to a “dump” load which will dissipate the excess power into heat.
Electricity generation using wind energy has been well recognized as environmentally friendly, socially beneficial, and economically competitive for many applications. Because of crucial fossil energy resources shortage and environmental issues the wind energy is very important resource for electricity production. Small wind turbines, photovoltaic systems, full cells and pump as turbines (PAT) in smallscale are main resources for distributed generation systems. Meanwhile, for remote areas wind energy beside photovoltaic system can combine as a hybrid system to provide necessary electric power of users. This system should be designed in such a way that the load demand of remote areas be provided with maximum reliability. Usually Direct coupled axial flux permanent magnet synchronous generator (AFPMSG), self-excited induction generator with gear box and permanent magnet synchronous generator(PMSG) with gear box can be used to connect to small wind turbine. In the past few years, there have been many studies on smallscale wind energy conversion systems. Authors of (Jia Yaoqin et al., 2002), (Nobutoshi Mutoh et al., 2006), (T.Tafticht et al., 2006), (Ch.Patsios et al., 2008) and (M.G.Molina et al., 2008) presented maximum power point tracking(MPPT) methods for smallscale wind turbines. (Etienne Audierne et al., 2009), (M.G.Molina et al., 2008), (Boubekeur Boukhezzar et al., 2005), (Md.Arifujjaman et al., 2005) and (Jan T.Bialasiewicz, 2003) described smallscale wind turbine furling system and modeled smallscale wind turbines.
The term frontier involves the concept of maximality in which the function sets a limit to the range of possible observations . It is therefore, possible to observe points below the production frontier for firms producing below the maximum possible output, but there cannot be any point above the production frontier, given the available technology. Deviations from the frontier are attributed to inefficiency. The need to measure inefficiency effects is the major motivation for the study of frontiers. Frontier studies are classified according to the method of estimation.  grouped these methods into two broad categories-parametric and non-parametric methods. For the parametric methods, it can be deterministic, programming and stochastic depending on how the frontier model is specified. Many researchers, including  have argued that efficiency measures from deterministic models are affected by statistical noise. This however, led to the alternative methodology involving the use of the stochastic production frontier models.  and  independently proposed the idea of stochastic measurement. The major feature of the stochastic production frontier is that the disturbance term is a composite error consisting of two components, one symmetric and the other one-sided. The symmetric component, V i , captures the random effects due to
The engine powers a high-pressure oil pump with an output pressure of 3 MPa and a flow rate of 60 litres per minute. The input torque of the pump shaft is 25 Nm at 3000 rpm. The hy- draulic winch can be fixed to tree trunks, stumps, or wooden pegs by lashings. The winch was tested at three locations with different assortments of wood. The results showed that the ex- perimental winch was practical for timber extraction and that <250 kN of force was needed for successful extraction. At the test sites, the expense of lumber removal was on average 140% greater with the winch than with a horse but the advantage of the hydraulic winch is high pulling force. Because of its small size and low weight, the unit can be easily handled by two workers, easily moved at short distances in small plots with rough terrain, and easily trans- ported among plots. With a one-man crew, the percentage of direct costs represented by wages dropped to 56%, and the percentage represented by fuel increased to 40%.
INTROD U CTION
The built environment is a major consumer of heat and electricity. The recognition of the environmental damage caused by the wasteful use of this energy coupled with advances in technology has led to a change in the view of the building as an energy system. Technologies such as photovoltaic facades and cogeneration allow a building to produce much of its own heat and power from cleaner sources. This raises new performance-related issues such as the best means of using the supplied heat and power, matching supply with demand, the interaction of the EG components with more traditional plant and suitable control of the EG sources in transient conditions. The answer to most of these questions requires some form of integrated building and systems simulation.
1. Int roduction
The traditional view of small business record keeping suggests that it is paper based and filed in a shoe box until such time that it is placed in the hands of the accountant for the preparation of the annual taxation return. Over the years the accounting profession and small business training providers have been trying to change the approach to record keeping adopted by small business operators, with a view to them holding better records and ultimately improving the management of their business. With the introduction of lower-cost and more user-friendly computerised accounting systems (CAS) there appears to be fewer obstacles to improved record keeping practices. This paper reports on the findings of a study that investigated small business usage of CAS. It begins with a review of the literature on the adoption of Information Technology (IT) and then considers the findings of the study in the context of the adoption factors identified. It concludes with a discussion of the issues that are associated with the usage of CAS and provides some direction for those organisations involved in advising small business operators about their record keeping.
2.0 EQUIPMENT FOR LAND PREPATION AND PLANTING OPERATION At the onset of the raining season, farmers are faced with the challenge of timely utilization of the soil moisture immediately the rain falls for planting operation. Failure to plant at the appropriate time can lead to poor crop establishment or even total failure a condition which is not desirable by farmers as this can greatly affect their productivity. Hence the need for a labour and time saving machines that will help farmers to fully maximize every useful time during planting season. In view of the above, Agricultural engineers and equipment fabricators have made concerted effort to develop several smallscale seed planters that have unique operational requirement in order to achieve maximum efficiency. Generally, planters can be categorized into Animal drawn, Hand held, Motorize and Tractor mounted.
B. Case study 2:
The second case study explores a different type of project with a number of special considerations. In this case, an existing limited SCADA solution was in place to read basic substation meter data, but only the G&T utility had primary access to the collected data. Knowing that the IEDs in its substations were capable of providing much more accurate data that was useful for planning and system management, the utility opted to pursue a new SCADA system. This system would collect data from substation IEDs in lieu of the antiquated substation meters, provide an interface for real-time monitoring and remote control, and use the new system to pass the required data to the G&T utility. The utility personnel had no expertise in SCADA systems or communications, but had a team that was willing and eager to learn. All information technology services for the utility are contracted to a third party, prompting the involvement of another team in the design and planning process. Upon initial inquiry, the utility had already explored the costs associated with deploying fiber optic links to its substations and found them to be prohibitive;
Malian households depend, in majority, on rain-fed agriculture for their food production. Overreliance on rain-fed agriculture limits the production output due to unreliable rainfall in the country. To mitigate this, the government has invested in rehabilitation of irrigation schemes to reduce dependence on rainfall. Through appropriate irrigation technologies and improved agronomic management practices agricultural productivity will be increased. This study determines the contribution of different irrigation systems to produce vegetables on household welfare in rural communities. The objective of the study was to contribute to improved livelihood of smallholder farmers in rural areas by use of irrigation systems in vegetables production. Three localities corresponding to two specific climatic regions favorable to vegetable crops production in Mali (Baguineda, Kati, Koulikoro region and Mopti region) was the study area. This study was guided by the production theory. Primary data was collected from 273 farmers selected proportionately from four wards (Fanafiecoura and Tieman, in Koulikoro region and Mopti and Dialango, in Mopti region) using face- to-face interviews. Secondary data from literature reviews was also used. Descriptive statistics and DEA functions were used for analysis. The Statistical Package for Social Scientists (SPSS), Stata and Excel programs were used for analysis. This study found that the irrigation systems as used in production of the three main crops to be characterized by inefficiency. Drip and sprinkling irrigation systems was relatively more economically efficient as compared with Californian system. The use of drip, sprinkling and Californian irrigation systems lead to greater benefits as compared to costs. The excess benefit (compared to costs) is realized more with drip followed by sprinkling and the third being California irrigation system. This study recommends more training and capacity building to the farmers in the study area with an aim of reducing their levels of inefficiencies in horticultural crop production. Farmers should be supported to adopt the use of drip, sprinkling and Californian irrigation systems which lead to greater benefits as compared to costs. Drip, sprinkling and Californian irrigation systems present a good opportunity for superior technical efficiency in vegetable production. These irrigation technologies should be promoted.
The majority of the maize producers in Guatemala are small-scale subsistence farmers. Approximately 60% of the country’s basic grains are produced on small farms that cannot produce enough food to satisfy the basic nutritional needs of a typical family (5–6 persons). The numerical importance of these groups of farmers, their precarious nutritional situation, and their high rate of demographic growth demand a long-term effort aimed at improving their productivity and income (Herrera and Jiménez 1992). The incorporation of new technologies into existing maize production systems should help achieve these goals. One strategy to effectively and rapidly increase yields is to promote more extensive use of improved maize varieties and hybrids by small-scale farmers. Although the availability of improved maize seed has steadily grown between 1977 and 1993, the supply has not sufficiently met demand, and access to this resource by small-scale farmers has been seriously limited. In 1993, 31% of the harvested maize area was sown with improved varieties (Lopez Pereira 1995); open pollinated varieties (OPVs) accounted for 19% of the total area while hybrids accounted for the remaining 12%. The principal users of the improved varieties, however, were medium- and large-scale farmers (Echeverría 1990). Although the percentage of area under OPVs is above the average for Central America (including México) and for Latin America as a whole, the percentage of area sown with hybrid materials is below the respective averages of both regions. Overall, the percentage of area sown with improved varieties is below the 40% reported for developing countries, excluding Argentina, Brazil, China, and South Africa (Heisey, Morris, and Byerlee 1998). Maize seed production in Guatemala
The most important objective for efficient biomass exploitation in the rural areas is to develop sustainable projects that integrate energy crops within agricultural activities by recovering marginal lands. In this context the most sustainable sources of biomass are lignocellulosic crops as Miscanthus giganteus, Arundo donax, sorghum or reed grass that can be used for heat and electricity production by direct combustion or by production of biofuel and biogas (Jurišiü et al., 2014). In the European policy for rural development provisions oriented on sustainable grow is estimated that maximum 30% of potentially available biomass can be used for energy production. Miscanthus biomass has a very good quality for combustion (similar as a light coal or wood), thermic value of Miscanthus biomass amounts to 9.2-17.7 MJkg -1 (Tomiü et al., 2011). In the last ten years, in the developed countries there were completed the technologies and equipments required in manufacturing and efficient burning of briquettes from sawdust, straw, Miscanthus, grasses and other forms of biomass. (I. Voicea, 2014). Romanian strategy on biomass exploitation for energy (excluding wood products) is in that point where potential of new frameworks will appear in order to set up projects for bioenergy production. In this context, this study reveal the opportunities for smallscale projects based on biomass combustion for heating systems that are sustainable for households and small farms.
The paper examines the impact of perceptions of the employees and computer efficiency on readiness of the employees to adopt ERP systems in small and medium-sized enterprises (SMEs). In carrying out the study, random sampling technique was used to select 200 employees who have worked at least 3 years in an SME. Relevant data were collected using structured questionnaire. The correlation analysis was used to test the hypothesis. The findings showed that Perceived Ease of Use, Perceived Usefulness, Perceived Personal Competence and Computer Efficiency have a positive influence on the employee’s readiness to adopt ERP systems. This paper suggests strategies which top management of SMEs can implement to encourage its employees in adopting ERP systems.
! Mike Bergey, President of Bergey WindPower Company, the largest producer of small wind energy systems in the United States concurred: “The industry has 6,000 - 7,000 machines interconnected in the U.S. all the way back to 1977. We have more than half a billion run hours on grid-intertied small-scale renewable energy systems, without any reported injuries or liability claims from the interconnected operation of these systems. This is in spite of the fact that most of these operational hours are with inverters that do not meet the emerging inverter safety standards such as IEEE 929-2000 and UL 1741. It has always been necessary for manufacturers to insure the safety of their equipment. This industry is no exception.