Generally, there are two types of solar hot water systems:
- Active systems (also known as split systems), where the solar panels are installed on the roof and the storage tank is located on the ground or in another convenient location.
- Passive systems, where the tank is installed on the roof above the solar collectors.
Active systems are often installed on townhouses where space is available for a ground mounted tank. Passive systems are often installed on apartment buildings where internal or ground space for tanks is limited or inconveniently located.
Independent information on choosing and installing solar hot water systems is available at:
- Solar Hot Water & Heat Pump Fact Sheet (Clean Energy Council)
- Solar Hot Water Systems (Your Energy Savings)
- Your Home – Hot Water Service
Other issues that might need to be considered when installing solar power on common property include, but are not limited to:
- any competing uses for unshaded northerly aspect roof space (the best for solar)
- roof access and material
- structural strength of the roof
- number of people the hot water system is supplying and how much hot water is required
- fencing off the system on a flat ‘active’ roof top
- tank location and its weight-bearing load
- connections to plumbing and power (gas or electric boosted). The type of any pipe or cable, the route taken, the method of affixing them, and the size of any hole in common property floors and walls and their impact on waterproofing and fire safety separations need to be considered
- size and location of panels and tanks and the impact on residents
- ensuring the integrity of any waterproof membranes is maintained or reinstated, particularly when mounting panels on flat roofs
Centralised Hot Water Systems
Particular care needs to be taken if replacing a centralised gas hot water system with a solar boosted system. The performance requirements are very different from those of a house or commercial building. The system needs to cope with peak loads where many residents might turn on the taps expecting a hot shower at the same time. Make sure the system and installer you choose has experience with residential strata installations.