M&V Solar Water Heating Guideline - Eskom

Measurement and Verification Standard Guideline for Low Pressure Solar Water Heating Systems v1r1
Table of Contents
1 INTRODUCTION ................................................................................................................... 7
2 OVERVIEW OF SOLAR WATER HEATING PROGRAMMES ....................................................... 7
2.1 Background ...................................................................................................................... 7
2.1.1 National Solar Water Heating Programme Launch .................................................. 7
2.1.2 Low Pressure Solar Water Heater Roll-out ............................................................... 7
3 OVERVIEW OF RESIDENTIAL SOLAR WATER HEATING TECHNOLOGIES ................................ 8
3.1 General ............................................................................................................................ 8
3.2 Solar Collectors ................................................................................................................ 8
3.2.1 Main Types of Collectors Used in South Africa ........................................................ 8
3.2.2 Collector Orientation ................................................................................................ 9
3.3 Influence of the Local Climatic Conditions on the SWH System Performance ............. 12
3.3.1 Climatic Zones in South Africa ................................................................................ 12
3.3.2 Evaluation of LPSWHS in respect of Installation Site Location and Climatic
/Seasonal variations ......................................................................................................... 14
3.4 High Pressure and Low Pressure Solar Water Heaters ................................................. 14
3.4.1 High Pressure Solar Water Heaters ........................................................................ 14
3.4.2 Low Pressure Solar Water Heaters ......................................................................... 15
4 Low Pressure Solar Water Heating Systems as Retrofit projects or Greenfield Projects17
4.1 Retrofit projects ............................................................................................................ 17
4.2 Greenfield Projects ........................................................................................................ 17
4.3 Low Pressure Solar Water Heating Systems as Retrofit Projects ............................... 17
5 Testing of Low Pressure Solar Water Heating Systems. .................................................... 17
5.1 Tests by South African Bureau of Standards (SABS) .................................................... 18
5.2 Essential Information from SABS Test Reports Used to Determine the Performance of
the Low Pressure Solar Water Heating Systems ................................................................ 18
5.2.1 Examples based on extracts from a typical SABS Test Report Performed on
LPSWHSs ........................................................................................................................... 19
5.3 Accuracy and Errors of the Tests at SABS ..................................................................... 22
6 Baseline of low pressure solar water heating projects ........................................................ 22
6.1 Typical Site Description ................................................................................................. 22
6.2 Electricity Usage Patterns in Low-cost Housing Environment ....................................... 24
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