• Energy Research

AbstractThe most important characteristics of solar thermal collectors are: long-term stability, high efficiency and architectural acceptable appearance for facades and roof installation. The efficiency of collectors is an important characteristic not only after their production, but more important is during their operation in outdoor - weathering conditions in different locations. How to solve the problem of the durability of collector's efficiency over a period of time and place them in buildings without destroying the architectural appearance? – These are some of the questions that are frequently asked. Some proposals of solving the current issues for of solar thermal collectors are discussed in this work.

AbstractThe most important characteristics of solar thermal collectors are: long-term stability, high efficiency and architectural acceptable appearance for facades and roof installation. The efficiency of collectors is an important characteristic not only after their production, but more important is during their operation in outdoor - weathering conditions in different locations. How to solve the problem of the durability of collector's efficiency over a period of time and place them in buildings without destroying the architectural appearance? – These are some of the questions that are frequently asked. Some proposals of solving the current issues for of solar thermal collectors are discussed in this work.

Sustainability usually refers to the ability to maintain a certain standard of human lifestyle without causing environmental damage or any other destruction to nature and biodiversity. It is beneficial for human health and well-being in addition to socio-economic benefits and contributes to environmental integrity. However, as Robert Swan (1956) once stated: “the greatest threat to our planet is the belief that someone else will save it”—this is true even today; namely, there are still serious threats to the planet and there is “a short time period” for action. We all have to be obliged to save the planet in which we live throughout our daily and local activities. In this study, the authors provide an overview of the meaning of sustainable tourism and its relationship to all global Sustainable Development Goals established by UN (2015) as one way to achieve a brighter sustainable future and society for everyone, leaving no one behind. More specifically, the case of Kosovo and its potential for the development of sustainable tourism is analyzed. In this case, the authors aim to present the potential to serve the local tradition, culture, diversity, and inclusiveness through sustainable actions in the tourism and hospitality sector.

Sustainability usually refers to the ability to maintain a certain standard of human lifestyle without causing environmental damage or any other destruction to nature and biodiversity. It is beneficial for human health and well-being in addition to socio-economic benefits and contributes to environmental integrity. However, as Robert Swan (1956) once stated: “the greatest threat to our planet is the belief that someone else will save it”—this is true even today; namely, there are still serious threats to the planet and there is “a short time period” for action. We all have to be obliged to save the planet in which we live throughout our daily and local activities. In this study, the authors provide an overview of the meaning of sustainable tourism and its relationship to all global Sustainable Development Goals established by UN (2015) as one way to achieve a brighter sustainable future and society for everyone, leaving no one behind. More specifically, the case of Kosovo and its potential for the development of sustainable tourism is analyzed. In this case, the authors aim to present the potential to serve the local tradition, culture, diversity, and inclusiveness through sustainable actions in the tourism and hospitality sector.

Different energy solutions are required to satisfy the energy demand of the world’s ever-growing population. Photovoltaic Thermal systems (PVT) could propose resolutions to tackle real-time issues regarding power generation. Life Cycle Analysis (LCA) is performed to compare the environmental impact and measure the energy across different PVT modules consisting of a-Si, CdTe, and CIS thin-film solar cells. The authors performed LCA to calculate the energy payback time (EPBT) and life-cycle CO2 emissions of residential rooftop and open-field PVT systems. The primary energy needed to produce thin-film PVT modules of 1 m2 cell area was considered in the present life cycle analysis studies operated using water as the working fluid. The annual net electrical energy savings at various Indian weather conditions, such as New Delhi, Jodhpur, and Ladakh, have been calculated. For the thin-film PVT systems, the calculated values of annual energy yield for three locations with average solar radiation levels and peak sun hours in the range of 600–1000 W/m2 and 6–8 h were reported. Results show that the CO2 emissions for rooftop installation of CdTe and CIS are around 200 and 156 kg/annually, which is lower than the open field installation of the same, where CO2 emissions were found to be 295 and 250 kg/year.

Different energy solutions are required to satisfy the energy demand of the world’s ever-growing population. Photovoltaic Thermal systems (PVT) could propose resolutions to tackle real-time issues regarding power generation. Life Cycle Analysis (LCA) is performed to compare the environmental impact and measure the energy across different PVT modules consisting of a-Si, CdTe, and CIS thin-film solar cells. The authors performed LCA to calculate the energy payback time (EPBT) and life-cycle CO2 emissions of residential rooftop and open-field PVT systems. The primary energy needed to produce thin-film PVT modules of 1 m2 cell area was considered in the present life cycle analysis studies operated using water as the working fluid. The annual net electrical energy savings at various Indian weather conditions, such as New Delhi, Jodhpur, and Ladakh, have been calculated. For the thin-film PVT systems, the calculated values of annual energy yield for three locations with average solar radiation levels and peak sun hours in the range of 600–1000 W/m2 and 6–8 h were reported. Results show that the CO2 emissions for rooftop installation of CdTe and CIS are around 200 and 156 kg/annually, which is lower than the open field installation of the same, where CO2 emissions were found to be 295 and 250 kg/year.

Solar energy is one of the most used renewable energy source in different applications nowadays. The direct method of harnessing solar energy is the solar thermal conversion method using solar absorbers. Solar thermal collectors are mainly used for heating water and for space heating. They capture incident solar radiation, convert it to usable thermal energy, and transfer the solar energy into a heat transfer fluid. All of these requirements should be accomplished economically with a minimum energy loss. One of the most important components of the solar thermal collector is the solar absorber. To be effective, the absorber should exhibit wavelength selectivity, i.e. have maximum solar absorbtance, minimum solar reflectance and thermal infrared emittance. A high solar absorbtance is required to collect as much of the incident solar radiation as possible and a low thermal infrared emittance contributes to minimize radiant energy losses. Usually, lightweight materials like, copper or aluminium, that have a high thermal conductivity, are used to transfer the absorbed energy from the surface to the media (fluid) which has to be heated. For high coefficient of efficiency of solar thermal collectors, the most important parts are: 1) spectral selective coatings that are composed of islands of metal embedded in a threedimensional matrix of dielectric with a solar absorbtance of α > 0.95 and an emittance of ε

Solar energy is one of the most used renewable energy source in different applications nowadays. The direct method of harnessing solar energy is the solar thermal conversion method using solar absorbers. Solar thermal collectors are mainly used for heating water and for space heating. They capture incident solar radiation, convert it to usable thermal energy, and transfer the solar energy into a heat transfer fluid. All of these requirements should be accomplished economically with a minimum energy loss. One of the most important components of the solar thermal collector is the solar absorber. To be effective, the absorber should exhibit wavelength selectivity, i.e. have maximum solar absorbtance, minimum solar reflectance and thermal infrared emittance. A high solar absorbtance is required to collect as much of the incident solar radiation as possible and a low thermal infrared emittance contributes to minimize radiant energy losses. Usually, lightweight materials like, copper or aluminium, that have a high thermal conductivity, are used to transfer the absorbed energy from the surface to the media (fluid) which has to be heated. For high coefficient of efficiency of solar thermal collectors, the most important parts are: 1) spectral selective coatings that are composed of islands of metal embedded in a threedimensional matrix of dielectric with a solar absorbtance of α > 0.95 and an emittance of ε