Solar Thermal Market Research Articles

Impact of fin material properties and the inclination angle on the thermal efficiency of evacuated tube solar water heater: An experimental study

In recent years, evacuated tube solar water heaters (ETSWH) have become popular due to their efficiency and low maintenance based on trends in India's solar thermal market. Numerous studies have focused on improving system performance. In the scientific literature, there is a lack of information on the selection of appropriate fin material and the benefits associated with it. The thermal efficiency (ηt) of ETSWH is directly impacted by the choice of fin material. In this context, the goal of this study was to assess the impact of copper and aluminum using fin material as well as the inclination angle on ETSWH's ηt. The experiments are conducted for mass flow rate (mwt) varying from 2 to 5l/h. With a mwt of 2l/h, the highest outlet temperature of 55°C was recorded, while the highest ηt was found at 41.2°C with a mwt of 5l/h. At all mwt, copper fin is more efficient than aluminum fin due to their superior thermal conductivity. Among the considered inclination angles, at an inclination angle of 30°, the efficiency of ETSWH is found to be optimal. ETSWH with a copper fin attains (ηt = 58.57%), which is more significant than the case when the aluminum fin is used (ηt = 51.50%).

Solar Thermal in the Nordics. A Belated Boom for All or Not?

<abstract> <p>In this work, the use of solar thermal energy in the Nordic Countries, especially in Denmark, is studied. Renewable energies, such as solar, are an important ally in the fight against Climate Change, with more countries betting on them. In the past, it may have been believed that the Nordic Region does not have enough solar radiation for solar energy to be profitable, but changes in the climate and technology have proven this statement to be wrong. The case of Denmark is a clear example, which has become a leading country when it comes to solar thermal energy. A study of the current Danish solar thermal market is conducted in this project in order to understand how this country is making the most out of this energy source. Three different plants are studied (Silkeborg, Vollerup and Gr?sten) and compared to those of other Nordic Countries (Akershus from Norway and H?meenlinna from Finland). It was found that the main difference between them is the size of the Photovoltaic (PV) parks. Whilst Denmark specialised in large-scale plants with a two-phase building process, the other countries are only using small-scale installations. After a deeper understanding of the Danish energy market, it is concluded that there is a solar thermal energy policy that allows its exploitation. Furthermore, an increase in the level of solar radiation in Denmark over the last decade has led Danish experts to believe that solar energy in the Nordic Countries is going to be even more profitable in the following years. It is believed that Denmark will continue its current expansion into this market and also that the other Nordic countries will soon enough join.</p> </abstract>

The International Standards for Solar Thermal Collectors and Components as a Medium of Quality Assurance

Within this publication a detailed overview about the national and international solal‘t1lel1nai standards is made. The various tests are described and a cross reference list for comparing the different standards is given. Moreover a certification model is presented and the advantage of third party assessment is carried out. The requirement for a solar thermal test laboratory to conduct independent third party assessment by means of an ISO/IEC17065 accreditation is given. Finally the concept of a quality system for solar thermal markets is explained and major advantages are outlined. Solar thermal systems and their components are described in various national and international standards. In Europe the standard EN12975 de?nes the regulations and requirements for solar thermal collectors. The standard EN12976 is established for the evaluation of factory made solar thermal systems. The EN12977 is the state of the art standard for the evaluation of custom build systems. Nowadays in Libya the standard ISO9806 for solar collectors and the standard ISO9459 for domestic water heating systems de?ne the regulations and requirements for solar thermal collectors and systems. In the meanwhile, empowered Center for Renewable Energy and Energy Ef?ciency Certi?cation Body is under construction. This body is working now to set the minimum requirements of the testing facilities of solar thermal systems. The international standard for collector testing is the ISO9806 and the standard ISO9459 Part2,4,5 for domestic water heating systems. Within the year 2013 a revision of the ISO9806 will be published and, for the ?rst time, a consistent harmonized standard for the main solar thermal markets will be set in force. Besides the various standards for solar thermal products a meaningful element for the quality assurance and the customer protection is third party certi?cation. Third party certi?cation involves an independent assessment, declaring that speci?ed requirements regarding a product are ful?lled. In a certi?cation process based on speci?ed certi?cation rules an authorized certi?cation body is con?rming that a solar thermal product has passed performance tests, reliability tests and further requirements according to the standards. In Europe a certi?cation body holds an accreditation according to EN45011. At international level the standard ISO/IEC17065 is in force. Test results as a basis for product certi?cation are determined by solar thermal test laboratories. The implementation and the business operation of such a solar thermal test laboratory is an important element within the national/regional solar thermal market. To ensure the quality of the products and to attend the role of an observer on the market, the test facility has to ful?ll a number of requirements. Besides the necessary technical equipment and the implementation of tests in accordance with the various national and international standards, the laboratory shall realize a quality management system to guarantee the quality of tests and services. Based on the technical equipment, the testing scope and an implemented Quality Management System (QMS), the test laboratory can achieve an accreditation according to ISO/IEC17025 as basis for independent third party testing. Independent testing and evaluation of solar thermal collectors and components like hot water stores and controllers offers an important medium for quality assurance. To guarantee a high degree of product quality and consumer protection a quality system for the solar thermal market is necessary. Core of the quality assurance of a functioning solar thermal market are the national standards body, which is developing standards and regulations as a working basis ill technical committees, the national metrology institute that guarantees the traceability of measurements on fundamental and natural constants, and ?nally the national accreditation body which ensures the conformity of the various actors to a speci?c standard. Laboratories work closely with the certi?cation authorities and apply the developed speci?c norms and standards. The certi?cation bodies must ensure the conformance of their test laboratories with the standard ISO/IEC17025, which include the quality standard ISO 9001:2008 and also include additional requirements. The traceability of the metrics of solar thermal testing laboratories is usually made with the help of calibration laboratories that are specialized on certain measurements. Those are also accredited and ensure the traceability of their measurements to the national meteorology institute. Other stakeholders are the group of importers and exporters and foreign investors who are on the national market in entrepreneurial activities, as well as the group of consumer organizations that represent the interests of customers. By means of good networking of stakeholders and focusing 011 the quality process, a high-quality and ?ourishing solar thermal market can be created.

A comprehensive analysis on development and transition of the solar thermal market in China with more than 70% market share worldwide

China is the second-largest economy country, and the largest country worldwide in total solar energy system capacity installed. More than 70% of total solar collector capacity worldwide is installed in China. The production of solar collector in China had decreased significantly from 64 million m2 in 2012 to 37 million m2 in 2017, corresponding to a reduction of around 40% of the market in 2012. There are very limited comprehensive studies in existing literature, which have investigated the reasons on the decline of Chinese solar thermal market. This study aims to identify the reasons from both the demand and the supply sides in details. Furthermore, with the rise of emerging markets, such as the rapid development of the “Clean Heating Initiative” for space heating in North China, solar heat industrial process, and the mandatory installation of solar domestic hot water system for residential buildings below 100 m in urban area, the Chinese solar thermal market is expected to recover soon, called “U-shaped curve” in this study. The market share of flat plate collector and evacuated tube collector is predicted to change in the near future. The research and development of flat plate solar collectors will increase continually in the market other than evacuated tube solar collectors like the past 10 years. The main driver for the solar thermal market development in China in the near future will be the demand from the urban area.

Technological Advances to Maximize Solar Collector Energy Output: A Review

Since it is highly correlated with quality of life, the demand for energy continues to increase as the global population grows and modernizes. Although there has been significant impetus to move away from reliance on fossil fuels for decades (e.g., localized pollution and climate change), solar energy has only recently taken on a non-negligible role in the global production of energy. The photovoltaics (PV) industry has many of the same electronics packaging challenges as the semiconductor industry, because in both cases, high temperatures lead to lowering of the system performance. Also, there are several technologies, which can harvest solar energy solely as heat. Advances in these technologies (e.g., solar selective coatings, design optimizations, and improvement in materials) have also kept the solar thermal market growing in recent years (albeit not nearly as rapidly as PV). This paper presents a review on how heat is managed in solar thermal and PV systems, with a focus on the recent developments for technologies, which can harvest heat to meet global energy demands. It also briefs about possible ways to resolve the challenges or difficulties existing in solar collectors like solar selectivity, thermal stability, etc. As a key enabling technology for reducing radiation heat losses in these devices, the focus of this paper is to discuss the ongoing advances in solar selective coatings and working fluids, which could potentially be used in tandem to filter out or recover the heat that is wasted from PVs. Among the reviewed solar selective coatings, recent advances in selective coating categories like dielectric-metal-dielectric (DMD), multilayered, and cermet-based coatings are considered. In addition, the effects of characteristic changes in glazing, absorber geometry, and solar tracking systems on the performance of solar collectors are also reviewed. A discussion of how these fundamental technological advances could be incorporated with PVs is included as well.

Transpired solar collectors in building service engineering: Combined system operation and special applications

One of the easiest ways to integrate renewable sources of energy into the heat producing system of a building is the application of transpired solar collectors. They are widespread in North America, where air heating is a common heating alternative, but they are gaining bigger share in the European solar thermal market nowadays. Their simple construction, maintenance-free operation and high working efficiency result in low capital and operating costs. The combination of TSC with other system elements results in additional benefits. Preheating the combustion air of large-scale boilers results in the increase of boiler efficiency and thus the reduction of natural gas consumption and CO2 emission. Whether to choose TSC or heat recovery unit for a certain air conditioning system has to be investigated by examining efficiency-influencing factors of both systems. Besides solar air heating, transpired solar air collectors can reduce the cooling demand on a building. Roof ventilation and nocturnal radiant cooling are two alternatives, which are being presented in the current paper.

Thermal performance assessment and improvement of a solar domestic hot water tank with PCM in the mantle

To develop an appropriate solar DHW (Domestic Hot Water) tank for residential dwellings and put it into the European solar thermal market for promotion, thermal performance tests of PCM (Phase Change Material) hot water storage tanks of both a prototype and an improved version with a water volume of 148 l and 35 kg PCM in the mantle has been carried out. The tank was designed to provide DHW for residential dwellings through a combination of solar and auxiliary heating, concurrently using PCM on the basis of cheap SAT (Sodium Acetate Trihydrate) as a thermal battery to shave off peak auxiliary power or to work under power outage. Heat transfer matching properties of the bottom and the top spirals separately for solar charge and auxiliary charge of the prototype DHW tank were ascertained in terms of heat exchanger capacity rate (HXCR) and the rule of thumb of boiler powers, respectively. Moreover, heat content of the PCM was estimated via a series of test cycles in order to infer its capacity and stability. It was found that there were some technical problems for the prototype tank module, such as mismatching property of the heat exchanger spirals, heat mixing phenomena during hot water draw-off. Thus, an improved tank was manufactured based on the test results of the prototype. Further tests indicated that the matching property of the top heat exchanger spiral was ameliorated for auxiliary charge and the heat mixing between hot water supply pipe and water tank was restrained during discharge, except that the length of the bottom spiral should be further reduced. Regarding the PCM in the mantle, it was inferred that the PCM heat content was somewhat lower than that of ideally working SAT. The PCM tended to perform stably under 16 test cycles with more than 3-month consecutive tests, implying no phase segregation occurred as that would degraded its performance.

Performance Enhancement of Solar Water Heater using Phase Change Materials (PCM): A Review

Solar water heater (SWH), one of the most popular solar thermal systems, accounts for 80% of the solar thermal market worldwide. This review paper presents the previous work on solar water heater using phase change material. PCM had been used in different part of heating networks including shell and tube type collectors, flat pate collectors and evacuated tube collectors. Recent findings about the effects of phase change material on various solar collectors are discussed. This review highlights the need for further research in improving the solar water heater using materials for latent heat storage.

Review and analysis of solar thermal facades

Harnessing solar energy to provide for the thermal needs of buildings is one of the most promising solutions to the global energy issue. Exploiting the additional surface area provided by the building’s façade can significantly increase the solar energy output. Developing a range of integrated and adaptable products that do not significantly affect the building’s aesthetics is vital to enabling the building integrated solar thermal market to expand and prosper. This work reviews and evaluates solar thermal facades in terms of the standard collector type, which they are based on, and their component make-up. Daily efficiency models are presented, based on a combination of the Hottel Whillier Bliss model and finite element simulation. Novel and market available solar thermal systems are also reviewed and evaluated using standard evaluation methods, based on experimentally determined parameters ISO 9806. Solar thermal collectors integrated directly into the facade benefit from the additional wall insulation at the back; displaying higher efficiencies then an identical collector offset from the facade. Unglazed solar thermal facades with high capacitance absorbers (e.g. concrete) experience a shift in peak maximum energy yield and display a lower sensitivity to ambient conditions than the traditional metallic based unglazed collectors. Glazed solar thermal facades, used for high temperature applications (domestic hot water), result in overheating of the building’s interior which can be reduced significantly through the inclusion of high quality wall insulation. For low temperature applications (preheating systems), the cheaper unglazed systems offer the most economic solution. The inclusion of brighter colour for the glazing and darker colour for the absorber shows the lowest efficiency reductions (<4%). Novel solar thermal façade solutions include solar collectors integrated into balcony rails, shading devices, louvers, windows or gutters.

WORLD AND RUSSIA SOLAR THERMAL POWER PLANTS MARKET TRENDS

The article deals with the world solar thermal power plants statistic data based on International Energy Agency materials including types of solar collectors (SC). Moreover, indicators of installed power of solar thermal stations (STS) per a thousand people, annual sales of STS and their structure by countries of the world are presented. There is only one producer of SC of European standards in Russia with small sales volume. Volume, coasts and producers of SC data in Russia are shown. The prospects of Russian solar thermal market are evaluated.

Uncertain future for solar thermal power

The World-Market Status special report – the solar thermal power market grew after a period of uncertainty during the global recession. Despite this growth, the future of solar thermal power is still unclear, unlike other alternatives (such as PV), which are gaining popularity thanks to continued cost reductions.

The International Standards for Solar Thermal Collectors and Components as a Medium of Quality Assurance

Within this publication, a detailed overview of the national and international solar thermal standards is made. The various tests are described and a cross-reference list for comparing the different standards is given. Moreover, a certification model is presented and the advantage of third-party assessment is carried out. The requirement for a solar thermal test laboratory to conduct independent third-party assessment by means of an ISO/IEC17025 accreditation is given. Finally, the concept of a quality system for solar thermal markets is explained and major advantages are outlined.Solar thermal systems and their components are described in various national and international standards. In Europe, the standard EN12975 defines the regulations and requirements for solar thermal collectors. The standard EN12976 is established for theevaluation of factory-made solar thermal systems. T e EN12977 is the state of the art standard for the evaluation of custom build systems. Nowadays in Libya the standard ISO9806 for solar collectors and the standard ISO9459 for domestic water heating systems def ne the regulations and requirements for solar thermal collectors and systems. In the meanwhile, the empowered Center for Renewable Energy and Energy Efficiency Certif cation Body is under construction. T is body is working now to set the minimum requirements of the testing facilities of solar thermal systems.The international standard for collector testing is ISO9806 and the standard ISO9459 Part 2, 4, 5 for domestic water heating systems. Within the year 2013, a revision of the ISO9806 will be published and, for the first time, a consistent harmonized standard for the main solar thermal markets will be set in force. Besides the various standards for solar thermal products, a meaningful element for quality assurance and customer protection is third party certification. Third party certification involves an independent assessment, declaring that specif ed requirements regarding a product are fulfilled. In a certification process based on specif ed certification rules an authorized certification body is confirming that a solar thermal product has passed performance tests, reliability tests and further requirements according to the standards. In Europe, a certification body holds an accreditation according to EN45011. At the international level the standard ISO/IEC17065 is in force.Test results as a basis for product certification are determined by solar thermal test laboratories. The implementation and the business operation of such a solar thermal test laboratory is an important element within the national / regional solar thermal market. To ensure the quality of the products and to attend the role of an observer on the market, the test facility has to fulfill a number of requirements. Besides the necessary technical equipment and the implementation of tests in accordance with the various national and international standards, the laboratory shall realize a quality management system to guarantee the qualityof tests and services. Based on the technical equipment, the testing scope and an implemented Quality Management System (QMS), the test laboratory can achieve an accreditation according to ISO/IEC17025 as basis for independent third party testing. Independent testing and evaluation of solar thermal collectors and components like hot water stores and controllers off ers an important medium for quality assurance. To guarantee a high degree of product quality and consumer protection a quality system for the solar thermal market is necessary. Core of the quality assurance of a functioning solar thermal market are the national standards body, which is developing standards and regulations as a working basis in technical committees, the national metrology institute that guarantees the traceability of measurements on fundamental and natural constants, and finally the national accreditation body which ensures the conformity of the various actors to a specif c standard.Laboratories work closely with the certification authorities and apply the developed specif c norms and standards. The certification bodies must ensure the conformance of their test laboratories with the standard ISO/IEC17025, which includes the quality standard ISO 9001:2008 and also include additional requirements.T e traceability of the metrics of solar thermal testing laboratories is usually made with the help of calibration laboratories that are specialized in certain measurements. Those are also accredited and ensure the traceability of their measurements to the national meteorology institute. Other stakeholders are the group of importers and exporters and foreign investors who are on the national market in entrepreneurial activities, as well as the group of consumer organizations that represent the interests of customers. By means of good networking of stakeholders and focusing on the quality process, a high-quality and flourishing solar thermalmarket can be created.

A review on loop heat pipe for use in solar water heating

Abstract In this paper, a comprehensive review on the loop heat pipe (LHP) for use in solar water heating (SWH) will be carried out. LHP is an efficient heat transfer device that could transport thermal energy over long distances, up to several tens of meters. It has some unique features over conventional heat pipe, e.g., gravity-unaffected and flexibility in its design and installation, which makes LHP particularly suitable for applications in SWHs. A significant literature review of the LHP technology will be illustrated, and the review results will be analyzed in terms of the performance characteristics and research methodology. For the performance characteristics, the steady-state and transient behavior of the LHP device will be examined. The research methods, i.e., theoretical analyses and computer simulations, and experimental investigations, will be analyzed. Although substantial work has been done in LHP studies, the opportunities for further work will be identified. This review will help recognize the problems remaining in the existing SWHs, remove the barriers to solar applications, identify new research subjects to improve the performance of the SWHs, expand solar thermal market potential throughout the world and broaden the application of LHP in solar water heating.

The Tunisian Solar Thermal Market: A Change of Scale

In the face of continuous increase in oil demand in the international market over the last few years, coupled with the stabilization of national hydrocarbon resources and the growth in the national demand of energy, since 2000 the energy balance in Tunisia has been characterized by an energy production deficit. Therefore, since 2005, Tunisia has committed to a national plan of energy conservation and renewable energy development, with the goal to reduce (fossil) energy consumption 24% by 2016 and 40% by 2030.Conscious of the energy challenges, the Tunisian Government through the National Agency for Energy Conservation (ANME) has established an ambitious program to promote solar water heaters (SWH), called “PROSOL”, which has already increased the installation rate of solar thermal from 7 000 m2/year to 80 000 m2/year. PROSOL is being implemented in three steps: residential, tertiary, and industrial. The Residential PROSOL financial mechanism focuses on the removal of two major barriers to the final consumer: the heavy initial investment and the high payback time in comparison with other conventional technologies. Promoting the quality of solar installations is a central objective of the program PROSOL Tunisia. Installation objectives in the tertiary sector during the period 2010 – 2016 are 30 000 m2, with 15 000 m2 already completed and 4 000 m2 expected completed in 2013 alone. Financing is supported by UNEP and ANME and is provided at several points in the project cycle including subsidies of feasibilities studies, capital cost, and maintenance. The third mechanism is Industrial PROSOL. Since 2010, this solar process heat program has been developed with the aim to install 30 000 m2 in the industrial sector during the period 2010 - 2016. This is a pilot phase for establishing a funding mechanism appropriate to the industrial sector, identifying barriers to the development and implementation of the first solar installations in industrial process in Tunisia. The first installation of 955 m2 in the textile sector will be in operation by the end of 2013.The PROSOL Program creates a real change of scale in the market for solar water heaters in Tunisia. The typical indicators of development continue to advance for this market as the programs advance, including a substantial increase in local manufacturing, local job creation, financial and energy savings to the State, and emissions avoidance. Finally, the requirement of QUALISOL and SWH certification based on Solar Keymark standards ensures a lasting quality and durability to the sustained growth of the solar thermal market in Tunisia.

The Concept of Test Centre Development with Respect to the Establishment of Test Capacities for Solar Thermal Markets

The proposed concept for sustainable and integral test centre development offers the opportunity to establish various test methods and procedures for the quality assurance of solar thermal collectors, systems and components on a regional, national and international market. The concept of an integrative test centre evolution is presented and discussed in its major phases. Moreover, the cross-linking and embedding of the concept in the context of a functioning quality infrastructure with the various market participants is presented. By means of anonymised practice examples of finished and ongoing projects the concept is demonstrated and evaluated. The results are presented and lessons learned are described. The implementation and the business operation of a solar thermal test facility is one important element within the specific market. To ensure the quality of the products and to attend the role of an observer on the market a test centre has to fulfill a number of requirements. Besides the necessary technical equipment and the implementation of tests in accordance to the various national and international standards the laboratory has to realize a quality management system to guarantee the quality of tests and services. On the basis of the technical equipment, the testing scope and the implemented quality management system the test laboratory can achieve an accreditation according to ISO / IEC 17025 as proof of independent third party testing. Within the concept based on a comprehensive analysis of the current situation, taking into account the economic and political conditions and the future vision as well as the development goal for testing methods a project plan with a specific roadmap is carried out in close cooperation with the local partners. Such solutions may consist in modular or complete technical concepts for a testing centre, of targeted training, continuing education activities or a Round Robin test to ensure the proper understanding and application of the testing methods. According to the experience of recent and ongoing projects it is recommended to conduct a detailed analysis which considers the state of the art, the local circumstances and the main objectives of the test centre. Moreover a high quality of documentation and knowledge transfer are evident to reach a sustainable result. Furthermore it can be concluded, that the training and the continuing education of the staff of the test centre is the most important factor, since their ideas and innovation assures the quality of work and the future of the test centre.Particular the systematic, sustainable and integrated approach of the method is new and innovative. The development and implementation of a solar test centre within the presented concept ensures a high reliability and reputation. Moreover it leads to a high level of consumer satisfaction, improved market transparency and may support a flourishing solar thermal market in the countries considered.

Study of a New Integrated Solar Collector

Even though the integration of renewable energies in new buildings is technically easy, the rise of solar thermal systems in the French market of energy renovation is limited by recurring constraints of implementation related to the installation of the storage tank. This is the reason why the Integrated Solar Collector (ISC) constitutes a very promising concept to develop. For both new buildings and renovation of the existing buildings, the ISC gives the opportunity to reduce the cost of installation and operation comparatively to a conventional Solar Domestic Hot Water System, because of their simplicity and passive operating process (without pump, nor controller). This second advantage is extremely important for the development prospects of the solar thermal market which is currently slowed down by the level of investment. The third advantage of our new ISC is the possibility of successful architectural integration, contrary to the currently available solutions with the storage installed on the roof.We developed a new concept of ISC adapted to the energy renovation with a multidisciplinary approach. Its design took into account various aspects: architectural integration (storage bellow the collector), energy performance (solar heat transfer at the bottom of the storage, fully insulated storage) and technological constraints (freezing risk). The project made it possible to study on the one hand its global performance (stratification, solar fraction) and on the other hand the free convective heat transfers inside the storage cavity. The approach used both numerical (architectural draft and design of the prototype, global modelling, and velocity / temperature fields) and experimental tools (test of heat, PIV on a cavity heated at the bottom, test of the prototype). The first prototype of ISC puts forward very satisfactory energy performances. Improvements are possible by enhancing thermal stratification in the storage system. Concerning the heat pipes operation against gravity, the project highlighted the current lack of technological solution adapted to our needs. The study of the building integration showed the architectural opportunities given during the renovation (new volumes) and the technical constraints which were solved (weight, storage insulation, freezing).

Standards and Certification Schemes for Solar Thermal Collectors, Stores and Systems — An Overview about the Latest Developments

During the last decade the use of solar thermal products has grown drastically all over the world. One reason for this increase was the implementation and continuous further development of specific standards series like the EN 12975 [1], EN 12976 [2] and EN 12977 [3] as well as the European certification scheme Solar Keymark which has become the most important certification scheme worldwide. The Solar Keymark being the world wide largest certification program with approx. 1600 certificates is not only accepted basically throughout Europe but is also introduced in other regions such as Northern Africa or Latin America and other countries like Japan or Canada. With the latest revision of the EN 12977 series Solar Keymark can now also be granted for so-called custom built solar thermal systems as well as for solar thermal heat stores.In order to support the global solar thermal market further developments of the International Standards and the implementation of a global certification schemes are essential. The first steps have been taken in the field of the solar thermal collectors. In 2011 ISO TC 180 decided to join their efforts in the review of the EN 12975 series dedicated to solar thermal collectors with CEN TC 312 to come up with a joined standard. The FDIS/ISO 9806 is currently under enquiry and is expected to come in force as EN ISO 98096 by the end of 2013. This standard will pave the way towards a global certification scheme which is currently under discussion between the already existing schemes Solar Keymark and SRCC with the support of certification bodies (e.g. AENOR and DINCERTCO) and Research and Testing Centre for Solar Thermal Systems (TZS) at ITW, University of Stuttgart being one of the leading test laboratories worldwide. Apart from the well-known collector technologies the EN ISO 9806 will cover in addition concentrating and tracking collectors, air collectors and PVT collectors.Besides the harmonization of existing standards another important topic is the development of new test procedures in order to make the existing standards applicable for new developments and to reduce testing costs as well as the implementation of new standards. Just lately ITW/TZS developed an indoor test procedure for complete solar thermal domestic hot water systems which will help to reduce the testing time and development periods. Examples for new standards are standards for the absorber durability, the durability and performance testing of evacuated tubes and the durability and performance testing of heat pipes which are currently under development in cooperation of ISO TC 180 and CEN TC 312.Additional work is done in the project SpeedColl funded by the German Government. Here the project partners ITW/TZS and Fraunhofer ISE are developing test procedure for accelerating aging testing of complete solar collectors.This conference contribution will give an overview of the current international standards, the ones to come and new test procedures. In the field of product certification it will provide a review of the existing Solar Keymark certification and an outlook to the currently discussed global certification scheme. The advantages of a global certification scheme on the future development of the worldwide market for solar thermal products will be described as well as the roadmap towards its implementation.

Solar thermal market in Taiwan

The long-duration of national programs has been the driving force behind the expansion of the local market of solar water heaters (SWHs) in Taiwan in the last two decades. This study examines the potential market for SWHs using the statistical data from end users and the 2010 Population and Housing Census. The current effective utilization rate of residential SWHs in terms of potential number of systems installed is estimated to be 11.8%. The analyses also show that the current national subsidy program has recently lost its momentum in expanding the market. Therefore, regional subsidy programs should become the main force in influencing the growth in sales. In addition, SWHs of larger scale would be particularly effective in industries. To promote such applications, a combination of performance-based and direct subsidy schemes or tax deductions can be offered to end users to promote the applications of SWHs in the commercial sector. Solar-assisted cooling systems are considered to be another potential application of solar energy, which is associated with energy saving and power consumption in commercial and residential buildings. A short review of the R&D activities is also given in this paper.

Financial Analysis of Solar Water Heating Systems during the Depression: Case Study of Greece

The use of solar thermal collectors is an economic alternative for water heating. In Greece more than 4 million m2 of collector area has been installed; however, the financial and economic crisis has dealt the solar thermal market a heavy blow. The aim of the paper is twofold: firstly, to present the new legislations and combined efforts taken by the government in order to give the solar thermal market a boost; secondly, to evaluate the effect of these efforts and calculate the new financial data from the citizens. For the promotion of solar water heaters, new legislations and concerted efforts are taken by the government. The effect of the new incentive program on the payback time of a typical glazed solar hot water system in Greece was investigated in this work. Long-term meteorological data from 47 stations are analyzed in order to evaluate the potential of solar water heater application at each site in Greece. The RETScreen software was used to predict the financial viability and the green house gas emissions reductions. The economical indicators showed that Tymbakion was the best site and Ioannina the worst. From the environmental point of view, it was found that on an average an approximate quantity of 1.47 ton of green house gases can be avoided entering into the local atmosphere each year.DOI: http://dx.doi.org/10.5755/j01.ee.23.1.1222

Possibilities for Utilization of Solar Thermal Energy in Multi-Family Buildings in Latvia

Possibilities for Utilization of Solar Thermal Energy in Multi-Family Buildings in LatviaThe paper is focused on analysis of the current situation for the solar thermal system market in Latvia. Solar energy potential and solar thermal market development in Latvia is compared with those in the countries, where solar irradiation is equivalent to that of the Latvian climate.This research also includes a description of the solar and pellet combisystem installed for a demonstration pilot project; the main parameters of this system are identified and the performance data for the first month of operations is analysed.An economic analysis for different heat supply scenarios from simulation data and real performance of the system is shown.