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

Coral reef habitat mapping in the Red Sea (Hurghada, Egypt) based on remote sensing

Remote sensing can give information about the configuration and composition of coral reefs, about the biophysical parameters of the seas and oceans in which they occur and about the changes over time of these elements. This paper deals with the classification of a Landsat7 ETM+ data set in order to identify the different bottom types (macro-algae, coral, sea grass and sand) occurring on the reefs offshore Hurghada, Egypt. Before classification, the radiance values received at sensor are corrected for atmospheric and water column effects. ‘Depth-invariant bottom indices’ are calculated and form the basis for classification. Besides the bottom type as an ecological classification, also a geomorphological classification is made. After contextual editing of the ecological classification, both results are combined into an open-ended hierarchical classification scheme. An in-depth accuracy assessment still needs to be undertaken but a mean accuracy between 47% and 83% is to be expected

Remote sensing as a tool for bathymetric mapping of coral reefs in the Red Sea (Hurghada – Egypt)

For monitoring coral reefs, a bathymetric map is useful as a base map. Different methods have already been developed to map bathymetry using remote sensing. Two main groups can be distinguished. One group is using active remote sensing data; the other is based on passive sensor generated multi-spectral information. In this article, the focus is on the passive data method. A modified «depth of penetration» mapping method was implemented on a Landsat7 ETM+-image over Hurghada (Egypt). Some 420 depth measurements were used for ground-truthing and accuracy testing. The accuracy test revealed that the resulting bathymetric map is useful for coral reef mapping, but care should be taken when using it. Deviations from reality were caused by assumptions inherent to the theory used, field sampling, satellite image characteristics and errors during implementation of the method.Een bathymetrische kaart vormt een van de basiselementen voor het bestuderen van koraalriffen. Verschillende methodes werden reeds ontwikkeld voor het bepalen van de diepte met behulp van teledetectie. Twee belangrijke groepen kunnen hierin onderscheiden worden. De ene groep baseert zich op informatie verkregen van actieve sensoren, de andere gebruikt multispectrale data afkomstig van passieve sensorsystemen. In dit artikel wordt enkel de passieve sensor methode besproken. Een aangepaste «Depth of Penetration» karteringsmethode werd toegepast op een Landsat7 ETM+-beeld over Hurghada, Egypte. 420 dieptemetingen werden gebruikt voor het absoluut determineren van de afgeleide diepte en voor het bepalen van de nauwkeurigheid van het resultaat. Hieruit bleek dat de resulterende dieptekaart gebruikt kan worden bij het karteren van de koraalriffen. Toch is enige voorzichtigheid bij het gebruik gewenst. Fouten werden veroorzaakt door veronderstellingen inherent aan de toegepaste theorie, de gebruikte waarnemingstechnieken, de kenmerken van het satellietbeeld en fouten bij de implementatie van de methode

Remote sensing as a tool for bathymetric mapping of coral reefs in the Red Sea (Hurghada-Egypt)

For monitoring coral reefs, a bathymetric map is useful as a base map. Different methods have already been developed to map bathymetry using remote sensing. Two main groups can be distinguished. One group is using active remote sensing data; the other is based on passive sensor generated multi-spectral information. In this article, the focus is on the passive data method. A modified «depth of penetration» mapping method was implemented on a Landsat7 ETM+-image over Hurghada (Egypt). Some 420 depth measurements were used for ground-truthing and accuracy testing. The accuracy test revealed that the resulting bathymetric map is useful for coral reef mapping, but care should be taken when using it. Deviations from reality were caused by assumptions inherent to the theory used, field sampling, satellite image characteristics and errors during implementation of the method

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