SR239 Practical means of assessing solar water heater performance and operation (2018)

Solar water heating (SWH) systems can save large amounts of energy. These systems are, however, not simple, so it is important to ensure that they are delivering the level of performance required.

Verifying that an SWH system is achieving a level of performance can be done cost-effectively to a basic level of accuracy. This study report describes practical means of establishing the overall SWH system performance.

A variety of other information can also be collected about the operation of a SWH system. This information can be helpful to the occupants interested in understanding their system and looking to improve how it performs. Operational information is also important to solar professionals looking to address any performance issues with the system.

This work follows on from a project looking at solar water heaters in New Zealand, which was reported in SR184 and SR188. Material in SR237 may also be of interest.