M&V Solar Water Heating Guideline - Eskom

Measurement and Verification Standard Guideline for Low Pressure Solar Water Heating Systems v1r1
EXECUTIVE SUMMARY
This document presents a standard guideline for Measurement and Verification for Low
Pressure Solar Water Heating Systems, and the application thereof in the context of Eskom’s
energy efficiency and demand-side management programme (EEDSM).
The Guideline is based on the review of essential topics related to the technology and
associated Measurement and Verification (M&V).
This document overviews the main solar water heating programmes based on the Low
Pressure Solar Water Heating Systems. The basic features of the solar water heating
technologies are considered in order to allow better understanding of the physical process
and their relation to the performance of the technologies in typical designs for South African
Conditions. The climate conditions in South Africa and the solar energy potential of the
country are reviewed.
Performance tests done by the South African Bureau of Standards (SABS) are reviewed and
their reported results are linked to the M&V work. Examples are shown to illustrate how to
allocate the parameters that are needed for the M&V process.
The document reviews the Retrofit and Green Field projects and recommends that the Low
Pressure Solar Water Heating Systems Projects will be considered as Retrofit projects since
prior to the retrofit there is a presence of electrical water heating process (although, by not
through dedicated electric water heater) at the project site.
Baseline process is presented and associated metering and other alternative procedures
leading to the baseline development are given in the document. Results from prior research
at the energy related issues at low-cost housing are presented. Examples and data from
energy audits are included based on the experience of the developers in similar projects.
For the determination of the energy savings, Option A is proposed as a suitable M&V
solution. The procedure is developed and the possible options are given with typical
examples.
The document answers the main M&V question related to Low Pressure Solar Water
Heating Systems, namely: “What is the thermal output of the systems and how it is related
to the base line determined?” This is done by the development of a performance model
based on SABS test results, geographical location of installation and hot water consumption.
The model outputs are properly used to evaluate, quantify and report the energy savings at
M&V process.
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