Solar water heating
Storage
Tank
Practical Action
Hot Water
Flat plate
collector
Figure 1: Passive and Direct Solar Thermal System (Illustration by Author, with reference
to CIBSE Solar Heating Design and Installation Guide, 2007)
Active systems contain circulation pumps to induce movement of the water or heat transfer
medium around the circuit.
Advantages
Greater flexibility in design and
location of system offered by
integration of circulation pumps
Greater efficiency induced through
consistent circulation of water/heat
transfer liquid
Running costs of electricity used to
operate pumps could be reduced
through installation of renewable
electricity power source, e.g. solar
photovoltaics
Disadvantages
Higher maintenance costs as
mechanical parts are present in the
system
Running costs higher as electricity
required for pump operation
Reliable source of electricity required
for operation
Table 2: Advantages and Disadvantages of Active Solar Water Heating Systems
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