Copyright © 2014
Ikhwezi Solar (Pty) Ltd, Novatherm CC, Solar Assist (Pty) Ltd
12
12.
System Selection and Sizing
12.1
Introduction
Individuals purchase solar hot water systems for
many reasons. Some buy to realise savings on their
energy spend, others out of concern for the
environment, others as they have no other means
of heating water or it could be a combination of the
above. Whatever the motivating factor is it is
important that the type and size of the system
selected are going to best meet the consumers’
needs and expectations.
12.2
System sizing
In deciding on the system required, apart from
conducting a site visit to ascertain the proposed
installation site and associated mounting, plumbing
and wiring considerations, the sales representative
should also consult with the prospective customer
as to their hot water requirements.
It is critically important that the prospective buyer
provide accurate information in this regard, as the
results of providing incorrect information can result
in a system that either over or under performs,
given the specific needs of the customer.
The onus is on the prospective buyer to provide the
sales consultant with an accurate disclosure of the
hot water requirements and usage patterns in order
that a load profile can be formulated.
A load profile would include information such as
how many showers are taken per day and how
many litres are used, how many baths are taken
and size of baths, how much hot water goes
towards washing dishes and doing laundry, etc.
Only once this information is analysed can a final
recommendation be made on system size.
12.3
System type
System type can relate to a number of system
characteristics as follows:
Direct vs. Indirect (refer section 5 above)
Close-coupled vs. Split (refer section 4 above)
The decision between direct versus indirect is
described in section 5 above, but basically this is
determined by whether or not frost or poor water
quality dictate an indirect system.
NOTE: THE DIRECT NOVASUN
(THERMOSIPHON/PUMPED) SOLAR
WATER HEATING SYSTEMS CAN BE
USED IN ALL CLIMATE AREAS OF SOUTH
AFRICA
The decision between close-coupled and split
system is largely an aesthetic decision based on
customer preference, but there is a cost implication
in that split system requires additional plumbing,
system controller, circulation pump and mounting
structures which translate into a greater installed
cost.
As the NovaSun systems have been SABS tested in
a thermo-siphon and pumped configuration and
registered with Eskom accordingly, a split system
installation can be claimed for on the rebate
programme if the system is a thermo-siphon or
pumped system. That is, even though the tank is
installed inside the roof there is enough space that
the tank is above the level of the collector/s,
allowing a thermo-siphon to operate or a pump to
force the circulation.
NOTE: Please visit www.novasunsolar.co.za for
more information on system.
