There is a certain trend in public support policies to require certain system performances/qualities rather than only collector performances/qualities. The logic is clear: Requiring a Solar Keymark certified collector is not enough to guarantee a good working system or a high energy yield. So far this is not possible because for a large part of the market (custom built) there is no final standard yet. And even for factory made systems the industry faces a lot of problems because there is not a definition for system family and an extrapolation procedure between the test of one system and the performance of systems of the same family (same manufacturer).

The work is important and urgent as some member states right now are considering establishing their own methods for system certification, so there is a risk that different national procedures will develop, which is exactly what the Solar Keymark is intended to avoid. From the member states there is a clear indication that if a good Solar Keymark procedure will be established, they would use this and not a special national one.  

This work package is focusing on the following main aspects:

1. Improvement of the standards for Factory Made Systems (EN 12976 Part 1 and 2 [2]) focusing on aspects that need clarification in order that certification of these products takes into account the different aspects of thermosyphon and forced circulation systems, as well as, uniform interpretation of criteria when performed by different Certification Bodies and Test Laboratories.
2. Improvement of the standards for Custom Built Systems (CEN/TS 12977 Part 1,2,4 and 5 and EN 12977 Part 3 [3]) considering the possibility of future certification of Storage tanks and complete systems according to improved standards.
3. Development of an extrapolation procedure that proves to be valid for different types of systems allowing for flexibility in the definition of families of systems and reducing test costs for the manufacturers.
4. Development of a procedure for converting the test results of the existing test method,  into results valid for the “EU reference tapping cycles”, necessary for Labelling of systems according to future European Directive.

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1. Clarification of the methodologies adopted for reliability tests of different system types and preparation of checklists for the vague criteria related to requirements of EN 12976 (Part 1). 
   
   The work proposed will include detailed description of procedures adopted by the test laboratories to perform the reliability tests, field tests of these procedures in running EN 12976 tests in 2009 and 2010; exchange and comparison of results and experiences in order to define a guide for uniform reliability test procedures.
   
   Discussion on all the requirements of the standard and identification of the points to be clarified based on the present experience of use of the standard.
   
   Output:
   
   Preparation of a guide for uniform reliability test procedures. Construction of a checklist for evaluation of the requirements of the standard EN 12976-1 considering all the aspects including the requirements for evaluation of Installers and Users documentation. The work to be developed can eventually guide to a proposal of revision of the standard EN 12976.  
   
   
2. Extrapolation procedure allowing for flexibility in the definition of families of systems and reducing test costs for the manufacturers  
   
   Preliminary investigations of a new method based on the ISO/ISO 9459-5 (DST) - utilising information from the collector testing - shows promising results. This proposal needs to be further elaborated and validated with system test results.
   
   Output:
   
   The expected final result is a procedure for performance prediction of systems in a system “family” based on one complete test of one system in the family plus maybe some supplementary testing of a system with another size. The procedure will be included in the Solar Keymark scheme rules – and “flexible system certification” will be possible. It is expected that this will lead to a dramatically increase in system certificates. 
   
   
3. Development of a procedure for converting the test results of the existing test method, into results valid for the “EU reference tapping cycles”, necessary for Labelling of systems according to future European Directive
   
   Work will be done to adapt the solar thermal EN standards to the requirements in the ANNEX IV – and give advice how to use existing EN standards for solar systems in ANNEX IV. Work will focus on a flexible procedure which can use separate tests of solar thermal systems/components and back-up boilers for determination of energy efficiency of the whole system – this to avoid immense testing of all possible configurations of solar thermal systems and boilers. Furthermore the solar standards will be adapted to the “EU Tapping Profile” as defined in CEN Mandate M/324 concerning Energy labelling.
   
   Output:
   
   Procedure that will allow based on the present EN standards for Factory Made Systems, to determine the Energy label according to the objective of European Union to have labels for water heater systems. 
   
   
4. Definition of a procedure for the assessment of the hot water comfort provided by the store being part of the factory made system.
   
   Hot water comfort in this context means the amount of hot water (at a specific temperature level) that can be withdrawn from the store during one continuous tapping even in cases where no solar input is available. This will be obtained by a good design of the storage tank enhancing stratification and, most import, reducing mixture of cold water from mains with hot water inside the tank. Furthermore the temperature level as well a possible fluctuations of the outlet domestic hot water temperature (e.g. in case the volume flow rate is changed) is a parameter that will be taken into account for the determination of the hot water comfort.
   
   In this sub- task a quantitative definition for this term and a test methodology will be developed. Finally, a proposal for introduction of this term in the Standards will be presented.
   
   The knowledge of hot water comfort is important information of the user and is also required for the assessment and comparison of different solar thermal systems.
   
   The different methods being available shall be investigated with regard to different system and storage concepts both, by theoretical and practical means. The advantages and disadvantages of the individual methods will be discussed between test labs and industry and synthesised in a new method. The new method will be validated by means of tests carried our for different system and storage concepts.
   
   Output:
   
   Procedure for determination and assessment of the hot water comfort provided by the store being part of the factory made system and proposal for implementation in EN 12976.

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• Proposal for determination of Hot Water Comfort of custom built systems
• Proposal for determination of Hot Water Comfort of factory made systems
• Proposal for Energy Labelling of custom built systems
• Proposal for Energy Labelling of factory made systems
• Improved extrapolation procedure for the determination of the performance of factory made systems
• Preparation of a Guide of procedures adopted for the reliability tests of factory made systems
• Establishment of a clear checklist for support of decision on verification of reliability requirements of Factory Made Systems/Custom built systems    
• Contribution to the revision and further improvement of standard series EN  12976 [2] and CEN/TS 12977 [3]
• Contribution to the growth of certificated Factory Made Systems due to reduced test costs (extrapolation procedure of test results)
• Clarification of needs of reliability tests for factory made systems and decision making on verification of product requirements
• Establishment of labelling procedures for solar thermal systems based on the present test methods of standards EN 12976 Part 1 and 2 [2] and CEN/TS 12977 Part 1,2,4 and 5 and EN 12977 Part 3 [3].
• Clarification of the term “Hot Water Comfort”  when applied to Solar Water Heating Systems and selection of the correct methodology for its determination.   

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