Economic and energetic assessment of industrial-scale solar thermal energy in the Visegrad Region

The Visegrád group's energy security is attributed to the national energy potential of each country. The energy potential results from the lack of crude oil and natural gas resources, limited access to the transmission network, and limited fuel storage. This bloc relies on raw material supplies from Russia, which is not evenly applied to all group members. Poland and Hungary have good storing potential, but it is not enough to achieve energy security and independence. Russia aims to keep control of this market while group members try diversifying their supplies to increase energy security. The purpose of this article is to present the energy balance in the Visegrád region. The analysis is based on the status of the renewable energy targets in the production, demand, import and export. Also, to determine the stability degree of these energy parameters. The material source is the literature and the energetic data from the European statistic's official agency Eurostat and European commission reports. From an energetic aspect, the four capitals were considered as a case study for a food processing plant with annual hot water demand of 43 MWh to evaluate the performance of the solar thermal energy. The simulation was conducted using T*Sol software considering 16 evacuated-tube collectors B. Schweizer Energy AG manufacturer. The chosen process heating system has a buffer tank and a continuous flow heater. Each collector was inclined according to the optimum angle for each case study. As a result, it was found that the energy demand in the Visegrád region is entirely related to the economic situation. In contrast, Political and energy development have a more significant impact than economic factors. From an energetic aspect, solar thermal energy is evident for Hungary and Slovakia since they have up to 20% solar yields compared to Poland and the Czech Republic. Nevertheless, the solar irradiation on the collector field is high enough to consider solar thermal energy solutions integrated into food and industrial processes

Linear Model of DHW System Using Response Surface Method Approach

Using alternative and clean energy resources is considered the most effective method to deal with the environment and energy crises nowadays. In this study a comparative analysis of FPC data for DHW are theoretically and experimentally evaluated to optimise the design parameters. A forced circulation solar heating system using flat-plate collector, is modelled using T*SOL as a new approach, for hot water requirements of a laboratory unit at Szent Istvan University, in Gödöllő, Hungary. The modelling shows 69% solar fraction and 510 kWh annual solar gain. Furthermore, the comparison study was based on these two factors, and the two results matched with 93.12% accuracy. After the modelling, practically, the exergy analysis was conducted to determine and highlight the losses of the system. Since Hungary is considered a cold climate country, it was found that the thermal and optical losses from the collector and the piping system were tremendous. Then all the necessary design parameters were studied to achieve the optimal working points using non-linear correlation response surface method (RSM, which has never been used as an analysis tool in the solar field) at two perspectives (solar fraction and annual yield) for seven factors using R script. The factors were collector surface area, inclination angle, glycol-water ratio, tank capacity, boiler capacity, desired hot water temperature, and volume flow-rate. We identified the most influential single factors using ParetoPlot and each two-factorsꞌ interaction using contour plots. The most influential factors on the solar yield are solar collector surface area, tank capacity, desired hot water temperature and volume flow rate by magnitude effects of +129.7, +125.3, +50.9 and +17.2 kWh per annum, respectively

Mathematical modelling and experimentation of soy wax PCM solar tank using response surface method

Worldwide, governments tend to reduce the CO2 emissions, and the storage of the solar energy system is still considered the most challenging problem to solve under the current state. Mainly, in relatively cold countries, as domestic hot water or for heat process services, where the loss in the tank is huge. Any improvement in the design can achieve a higher solar yield. Since water is the usual medium for heat storage, the integration with phase change material (PCM) can store energy when there is abundant energy and release it when it is needed. In this study, we conducted a capsulated PCM soy wax 52⁰C in an insulated water tank filled with 5 litres of water. To estimate the appropriate number of samples and the quantity of the PCM at two temperature levels using the response surface method with non-linear correlation for the charging phase. The results show 3.16, 0.95, 0.38 first degree magnitude effect for temperature, sample numbers, and wax quantity respectively and 0.29, -0.38 second-degree magnitude effect for quantity and temperature. In addition, an illustration of each two-factors interaction contour plots. &nbsp

Mathematical modelling and experimentation of soy wax PCM solar tank using response surface method

Worldwide, governments tend to reduce the CO2 emissions, and the storage of the solar energy system is still considered the most challenging problem to solve under the current state. Mainly, in relatively cold countries, as domestic hot water or for heat process services, where the loss in the tank is huge. Any improvement in the design can achieve a higher solar yield. Since water is the usual medium for heat storage, the integration with phase change material (PCM) can store energy when there is abundant energy and release it when it is needed. In this study, we conducted a capsulated PCM soy wax 52⁰C in an insulated water tank filled with 5 litres of water. To estimate the appropriate number of samples and the quantity of the PCM at two temperature levels using the response surface method with non-linear correlation for the charging phase. The results show 3.16, 0.95, 0.38 first degree magnitude effect for temperature, sample numbers, and wax quantity respectively and 0.29, -0.38 second-degree magnitude effect for quantity and temperature. In addition, an illustration of each two-factors interaction contour plots

Effect of in series and in parallel flow heater configuration of solar heat system for industrial processes

The boiler is an enclosed vessel that transfers the energy from fuel combustion or electricity into hot water or steam. Then, this hot water or pressurized steam is used for transferring the heat to a certain heat process. Usually, the required hot water or steam keeps on varying throughout the day which also may be implied on the daily or monthly load. Therefore, several configurations of connecting the boiler into the solar heating system ensure the temperature of the final output. The boiler can be connected in series or parallel to improve the efficiency of the overall process as well as to reduce the running costs. This paper presents a simulation study of a solar heating system for industrial processes. Two flow-heater system configurations are designed for covering the heat demand of a pasteurising factory existing in Budapest, Hungary. The configuration “A” consists of a solar heating system for hot water preparation using in series flow heater configuration. While configuration “B” consists of the same solar system but with a parallel flow heater configuration. These system configurations are modelled using T*sol software for evaluating the system performance under the Hungarian climate from five different aspects: required collector area, glycol ratio, volume flow rate, relative tank capacity, and tank height-to-diameter ratio. According to the optimum design parameters, in series configuration is better than parallel by 3.14% at 45 m² collector area, 0.45% at 25% glycol ratio, 0.42% at 50 l/h · m² volume flow rate, 2.05% at 50 l/m² relative tank capacity, and 0.42% at 1.8 tank height-to-diameter ratio respectively. The results show that in series configuration is better in terms of solar fractions than parallel configuration from all five aspects

A model of Lean Management for organizational innovation: cases in visegrád and AFTA

Originated as a production management philosophy, Lean Manufacturing has successfully transferred and implemented globally. Lean genealogy studies have been conducted, indicating the essential concept now evolves to Lean Management (LM), which is applicable to many branches of production and services management, viz quality and productivity, human resources, knowledge and technology, etc. Innovation has been made to ensure a smooth customization of knowledge and principles, tailored to each organization who is eager to implement this state-of-the-art management system. However, failures are becoming commonplace due to the lack of understanding the core values, and insufficient intensification of compensation for cultural differences. In this paper, cases of implementing LM across the Visegrád group (V4) and the ASEAN Free Trade Area (AFTA) from previous literature are taken into consideration. Factors that differentiate the characteristic of LM are brought to discussion. Therefore, the discovered gap between the two trade blocs urges the in-depth amendment and modification of employed concepts, tools, etc. A model is consequently elaborated, which aims at facilitate the managerial decision-making process regarding knowledge transfer of LM between V4 and AFTA, based on critical factors related to human, technology and culture, i.e. Labor cost, Manual requirement, Awareness, Continuous Improvement culture. This model can be used to predict the change should be made, or the criterion should be fulfilled to transfer the implementation and knowledge of LM effectively

The use of Lean Six-Sigma tools in the improvement of a manufacturing company – case study

Handicraft production is usually chaotic and difficult to monitor, since its products and manufacturing processes are complex. As all the manufacturing steps rely on varied skill levels of the workers, the situation is even more stochastic. There are several common problems, such as inappropriate production method, line unbalance, excessive stock, lack of production planning and control phases, etc. They stem from the lack of suitable operation model, redundant workforce usage, and insufficient internal training activities, which lead to the waste of human resources. In this paper, a roadmap to improve the operational efficiency of handicraft manufacturing is suggested, using Lean-Six Sigma methodology and tools. A case study is conducted in a Vietnamese firm to show the validity of the approach