
- 3 floors
- 12 units
- completed 1923
90 evacuated tubes and 2 gas boosters replaced an ageing gas bolier with a payback period less than 2 years.
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Rooftop solar panels for hot water system
The owner of a 12 unit apartment block in Darlinghurst, Sydney wanted to reduce the cost of heating the hot water via an ageing gas boiler (almost $1600 per month – in 2005). The owner also wanted a cost effective way of fitting evacuated tube collectors on the roof of the building to then feed into the existing storage tanks. The three key requirements were to limit the costs by using as much of the existing plumbing and water storage system as possible, to ensure low maintenance in the future, and also to minimise any disruption or inconvenience to the tenants.
The solution - 90 evacuated tubes (3 x 30 tube collectors) & 2 Bosch gas boosters as a backup heating auxiliary were installed. The water was fed straight into 3 existing storage tanks in the ceiling cavity.
The modular design of the system allowed the components to be quickly unloaded and carried up the internal stairs and easily passed through the small roof access door without the additional expense of hiring a large crane.
An added bonus to this installation is that the space in the tiny yard that was reclaimed and the old boiler room was adapted into a laundry.
Cost: approx $9,000
Installation time: approx 4 weeks
Savings: up to 80% reduction in gas bills. The measurement was a simple comparison of gas bills before and after the installation
Payback period: less than 2 years