Subtask A: Collectors

The objective of this subtask is to examine existing testing and certification procedures for low-temperature evacuated tube and flat-plate collectors, air heating collectors, medium- to high-temperature concentrating collectors, to identify weaknesses, inconsistencies in application, and significant gaps. The research will result in new or improved tests that can be communicated to ISO/TC 180 for consideration in updating old standards or developing new standards. Results will be promoted to certification bodies when they are relevant for consideration in how product certification is implemented. Methods include round robin tests to refine existing test procedures, in cooperation with researchers, industry and certification bodies involved in these technologies. The task will also establish ongoing information dissemination and communications to provide necessary information and feedback among participants, industry, and certification bodies to promote harmonized standards and coordination among certification bodies.

• Road Map
• Work Plan

The activities in this subtask are intended to produce research results that can inform participants, industry, testing labs and certification bodies with new information on testing that will promote harmonized testing and certification.

Activity A.1 – Roadmap of Collector Testing and Certification Issues

Develop a roadmap on existing collector testing processes to serve as a guide to how tests and standards are applied and how they relate to certification, and to identify gaps, inconsistencies and weaknesses along with approaches to addressing problems. Develop recommendations for improving the system for emerging technologies where standards and testing are under development, for example by exploring the possibility of “provisional” or “light” certifications based on Technical Specifications rather than final CEN or ISO standards.

Activity A.2 – Low-to-Medium Temperate Collector Test Procedures, Standards and Simulation

Based on priorities and issues developed in Activity 1, this task will analyze current issues in flat plate and evacuated tube collector testing and certification and initiate worldwide round-robin tests to identify variations and problems in procedures. Issues the teams will consider for research will include but not be limited to:

• wind speed dependence and comparability of ratings when tested at different wind speeds,
• whether infrared effects explain some of the variations in outdoor and indoor testing (note that the Germans use a “cold baffle”- two glazings with cool air passing between; this will be very useful to see what the bias is in their testing, versus FSEC/Bodycote that do not attempt to alter the IR flux), and
• how the most recent changes in the EN12975 series of standards apply to these issues. The research will also involve a comparative analysis of how standards are applied in different countries and whether there are inconsistencies or differences that should be resolved to promote harmonization of standards and certification.

Where appropriate researchers will review component test simulation tools to identify any issues in their application to current SHC technology and opportunities to adapt to new applications. CTSS, Dynamic System Test, Input-Output, and recent regression modelling results for using measured data to determine parameters in models will be investigated. Research testing and measurement standards will be considered to identify conditions used in ratings, and share information needed to promote harmonization across participating countries.

Researchers will review current laboratory approaches to qualification and safety testing to identify inconsistencies, gaps, and problems specific to low- to medium-temperature collectors. Research will also examine the implications of component/material substitution on performance and lifetime and characterize key components. Based on the results researchers will develop recommendations for research or improved practices to resolve issues. Topics may include but will not be limited to:

• Hail testing (incident angles, ice vs. steel balls, type/handling of ice [clear, opaque, cracks,…], test to failure approaches) and moisture, differences in testing related to different types of collectors.
• Determining whether quality ratings and degradation estimates are feasible based on tests and their implications for system life, lifetime performance, reliability and warranties.
• Mounting structures; lightning protection, working fluids and other topics raised by growing installations in varied locations, and will address what is appropriately addressed in component and system testing and certification versus building codes and installer responsibility.
• Component and material substitution and how it is addressed in testing and standards, including when substitutions should be considered significant enough to require new testing and standards. For example with change in glass thickness from 4 to 3.2 mm, substituting thicker aluminum for copper on absorber fins, fin bonds going from fused to mechanical. Heat transfer fluids are also an issue, for example in the U.S. heat transfer fluids in systems with single-wall heat exchangers must be certified by the Food and Drug Administration (FDA) as food-grade, while in Europe standards are different.

Activity A.3 – Air Heating Collector Test Procedures, Standards and Simulation

Based on priorities and issues developed in Activity 1, for closed loop collectors this task will examine common practices for testing and certification of existing collectors as applied by Bodycote, Fraunhofer ISE and others (5 collectors already certified by SRCC using ASHRAE, 3 tested by ISE using modified EN12975) to identify issues in ASHRAE 93/96, how collectors are certified by SRCC, Solar Keymark and Australia.

For open loop collectors research will examine common practices for testing and certification of existing collectors as applied by Bodycote and others, and research at NREL and other labs. Work will be coordinated with SRCC to apply results where they are appropriate for equipment certifications which are in process.

Work on both open and close-loop collectors is expected to include but is not limited to:

• Examining how growing markets would benefit from more information on performance and better tests.
• Characterizing issues involved in passive/active building integration of systems.
• Studying test procedures and promoting round-robin tests, recommending changes in requirements and certification schema for different types of collectors as needed.

Where appropriate researchers will review component test simulation tools to identify any issues in their application to current SHC technology and opportunities to adapt to new applications. CTSS, Dynamic System Test, Input-Output, and recent regression modelling results for using measured data to determine parameters in models will be investigated. Research testing and measurement standards will be considered to identify conditions used in ratings, and share information needed to promote harmonization across participating countries.

Researchers will review current laboratory approaches to qualification and safety testing to identify inconsistencies, gaps, and problems specific to air heating collectors. Research will also examine the implications of component/material substitution on performance and lifetime and characterize key components. Based on the results researchers will develop recommendations for research or improved practices to resolve issues. Topics may include but will not be limited to:

• Hail testing (incident angles, ice vs. steel balls, type/handling of ice [clear, opaque, cracks,…], test to failure approaches) and moisture, differences in testing related to different types of collectors.
• Determining whether quality ratings and degradation estimates are feasible based on tests and their implications for system life, lifetime performance, reliability and warranties.
• Mounting structures; lightning protection, working fluids and other topics raised by growing installations in varied locations, and will address what is appropriately addressed in component and system testing and certification versus building codes and installer responsibility.
• Component and material substitution and how it is addressed in testing and standards, including when substitutions should be considered significant enough to require new testing and standards.

Activity A.4 – Concentrator Collector Test Procedures, Standards and Simulation

Convene active parties (either virtually or face-to-face) engaged in Alanod meeting, IEA research, and recently formed SRCC standards subcommittee to develop improved methods for measurement, characterization and testing to coordinate efforts, characterize strengths and weaknesses of existing approaches embodied in ASTM905 efficiency test methods.

Research current approaches and develop new procedures and standards as needed for in-situ testing of large collectors, for example placement and calibration of environmental monitoring, time periods for collection, approaches to normalizing and extrapolating data, etc. CEN/TC 312 meetings created a resolution regarding revision of EN12975-1 and 2 and implementation of M/369 recommended clarifying how present standards apply to tracking and/or concentrating collectors. Action on the resolution will be considered in order to avoid duplication of effort and to leverage other work.

Assess applicable research conducted on fresnel, linear, dish, fixed mirror, and other novel configurations (e.g, fixed receiver, either line or point) conducted in Europe, Australia, and U.S. (including for CSP) to determine their applicability to measurement and testing needs of solar thermal products.

Conduct a review of component test simulation tools to identify any issues in their application to current SHC technology and opportunities to adapt to new applications. Research testing and measurement standards to identify conditions used in ratings, and share information needed to promote harmonization across participating countries.

Researchers will review current laboratory approaches to qualification and safety testing to identify inconsistencies, gaps, and problems for concentrating collectors. Research will also examine the implications of component/material substitution on performance and lifetime and characterize key components. Based on the results researchers will develop recommendations for research or improved practices to resolve issues. Topics may include but will not be limited to:

• Hail testing (incident angles, ice vs. steel balls, type/handling of ice [clear, opaque, cracks,…], test to failure approaches) and moisture, differences in testing related to different types of collectors.
• Determining whether quality ratings and degradation estimates are feasible based on tests and their implications for system life, lifetime performance, reliability and warranties.
• Mounting structures; lightning protection, working fluids and other topics raised by growing installations in varied locations, and will address what is appropriately addressed in component and system testing and certification versus building codes and installer responsibility.
• Component and material substitution and how it is addressed in testing and standards, including when substitutions should be considered significant enough to require new testing and standards.

Activity A.5 – Communication and Adoption of Results

In coordination with Subtask B, develop efficient means of communication for the results of the overall task including the Internet, promotion of web conferences and meetings, and other tools identified in the course of the task.

• Identify existing groups working in the subject of technology, testing and standardization and establish links with these groups to engage them in communications and harmonization effort.
• Develop a communication plan for the target audiences that draws on the current IEA-SHC communication plan to further target industry, standards and certification bodies, testing laboratories, and other supporting organizations.
• Prepare and maintain a web page that includes work in progress in addition to final deliverables for projects with implications for testing and standardization, with material open to outside groups or limited to participants as appropriate.
• Establish an alert system for information on relevant data from IEA tasks, TC standardization groups, and certification bodies (Solar Keymark, SRCC, Office of Australian Renewable Energy Regulator) to actively notify interested parties of developments rather than relying on their searching for the information.
• Establish a regular forum for participants and outside persons to pose questions or make suggestions regarding testing processes so that developers of new technologies have an entry point into the testing process, and existing technology practitioners have a place to raise questions or provide input.
• Actively recruit participation from other countries including China and India either as direct participants in research or as observers. Organize joint meetings in conjunction with Solar Keymark networking or other events (Standardization Technical Committee meetings) to promote ongoing action to harmonize standards, testing and certification. Organize more meetings with broad international appeal and dispersed locations like ISES meetings. Work to make standards and testing a distinct track in larger meetings where researchers in this task can be involved as individuals in standards development.

Subtask B: Systems

The objective of this subtask is to examine existing testing procedures for entire systems and identify weaknesses, inconsistencies in application, and significant gaps. Testing research will investigate component/material substitution issues, including implications for qualification and safety testing. System performance characterization, testing, simulation and modelling and extrapolation will be investigated to help clarify key issues including accelerated aging testing and performance prediction. The research will extend to analyzing how system testing and performance characterization results can be applied to analysis and public dissemination of public benefit indictors, including environmental, economic, energy and occupant comfort indicators for solar thermal systems. Where appropriate, research results that have implications for testing standards will be communicated to ISO/TC 180 and/or certification bodies to consider. Methods will include round robin tests to refine existing test procedures, in cooperation with researchers, industry and testing bodies involved in these technologies. The task will also establish ongoing information dissemination and communications to provide necessary information and feedback among participants, industry, and certification bodies to promote harmonized standards and procedures.

• Work Plan

The activities and projects in this subtask examine testing and certification procedures for systems. By examining current practices, weaknesses in existing methods can be identified and improved, gaps in existing methods and processes can be identified and redressed, and inconsistencies in the application of existing methods and processes can be reduced by sharing information and promoting harmonization of procedures. One of the objectives will be a more sound, well-documented and widely adopted set of procedures for estimating the environmental, energy and economic impacts of solar thermal systems over their lifetimes. Another objective will be a more sound, well-documented and widely adopted set of procedures for understanding how system design and components interact with buildings and other equipment in delivering reliable and comfortable space conditioning, reliable hot water, energy surety, and other indicators of solar thermal value to end-users.

Activity B.1 – Roadmapping of Systems Issues

Convene a meeting of experts to discuss issues and define research needs in more detail. Conduct research to define the limits/boundaries of solar thermal systems within the context of building integration, what is the solar thermal system in the contexts of storage, cooling, heating. Work will also consider how systems should be defined for incentive programs; characterizing quantity and quality of heat; and appropriate parameters for due diligence assessments for larger custom systems. Investigate ranges of tolerance/acceptable uncertainty in performance and/or define bands of acceptability for performance. Examine existing performance testing and research applied to systems and promote round robin tests to investigate variations in practices and procedures and their impact on test results, for example for passive systems where there are problems in producing comparable results for separable thermosiphon systems versus ICS and non-separable thermosiphon systems.

Activity B.2 – Component/Material Substitution, Qualification and Safety Testing

Research how component and material substitution should be addressed in testing and standards, including when substitutions should be considered significant enough to require new testing and standards. For example, the substitution of Grundfos pumps for Wilo pumps, or substitutions of different storage components.

Research how to extrapolate changes within a model line. For example, how to treat changes in the size and or number of collectors even though their “construction” is identical, or tank volume changes (with the same stratification devices if any are used). There has been work on procedures that use a complex mapping of solar fraction vs area/volume by simulation, with variations for climate, draw volume, and other factors. Another approach is to “test at extremes” and interpolate. Examining various approaches and determining their strengths and weaknesses will provide laboratories, industry and certification bodies with better, more standardized approaches to deal with sizing issues.

Survey current laboratory approaches to qualification testing and how they relate to systems to identify inconsistencies, gaps, and problems. Develop recommendations for research or improved practices to resolve issues, building on the base of experience developed in collector testing.

Investigate (with input from test laboratories, industry and certification bodies) whether quality ratings and degradation estimates for whole systems are feasible based on tests and their implications for system life, lifetime performance, reliability and warranties. Determine to what extent individual collector and component testing can be aggregated into whole system predictions of lifetime, performance, and reliability.

Survey current practices for safety-related testing and certification to identify issues, including lightning protection, over-temperature protection, and other factors raised by growing installations in varied locations, and address what issues are best considered in component and system testing and certification versus building codes and installer responsibility.

Activity B.3 – Simulation and Modelling

Conduct a review of component test simulation tools to identify any issues in their application to current SHC technology, opportunities to adapt to new applications, and issues in applying them to systems analysis. CTSS, Dynamic System Test, Input-Output, and recent regression modelling results for using measured data to determine parameters in models will be investigated. Research testing and measurement standards applied to combi-systems, identify conditions used in ratings, and share information needed to create/apply common methods across participating countries.

Activity B.4 – Analysis and Public Dissemination of Benefit Indicators

Examine value and application of test results to quantify environmental benefits including carbon footprint, lifecycle disposal and recycling issues, energy payback calculations, and others suggested in the course of research. Recommend further research in areas where benefits estimates are inadequately supported by testing and characterization efforts, and recommend improvements that could strengthen the technical basis for benefits estimates. Although these benefits measures depend on basic performance information, there are questions concerning how well current measures support these benefits estimates and how the scientific basis for them could be improved to help industry gain public and policy support.

Examine the relation between test and characterization information and consumer perceptions of issues such as “comfort” to identify areas where existing test and measurement data are inadequate for quantifying these factors. An example would be the differences users sense between hydronic, forced-air and radiant space conditioning systems and how solar systems perform in these different applications. Related performance issues that go beyond thermal performance include reliability and security of systems and ability to cover loads.

Activity B.5 – Communication and Outreach Coordination

In coordination with Subtask A, develop efficient means to communicate the results of the overall task including the Internet, web conferences and meetings, and other tools identified in the course of the task.

• Identify existing groups working in the subject of technology, testing and standardization and establish links with these groups to engage them in communications and harmonization effort.
• Develop a communication plan for the target audiences that draws on the current IEA-SHC communication plan to further target industry, standards and certification bodies, testing laboratories, and other supporting organizations.
• Prepare and maintain a web page that includes work in progress in addition to final deliverables for projects with implications for testing and standardization, with material open to outside groups or limited to participants as appropriate.
• Establish an alert system for information on relevant data from IEA tasks, TC standardization groups, and certification bodies (Solar Keymark, SRCC, Office of Australian Renewable Energy Regulator) to actively notify interested parties of developments rather than relying on their searching for the information.
• Establish a regular forum for participants and outside persons to pose questions or make suggestions regarding testing processes so that developers of new technologies have an entry point into the testing process, and existing technology practitioners have a place to raise questions or provide input.
• Actively recruit participation from other countries including China and India either as direct participants in research or as observers. Organize joint meetings in conjunction with Solar Keymark networking or other events (Standardization Technical Committee meetings) to promote ongoing action to harmonize standards, testing and certification. Organize more meetings with broad international appeal and dispersed locations like ISES meetings. Work to make standards and testing a distinct track in larger meetings where researchers in this task can be involved as individuals in standards development.