If you have common hot water for your apartment block it can be powered a number of different ways.
Cogeneration systems are rated the most efficient central hot water systems to install. After this gas-boosted solar, heat pump systems, electric-boosted solar and then gas.
It is a major infrastructure project to change your common hot water system type after the property developer has installed it.
At Freesia Gardens, we investigated changing our system from gas with 3 storage tanks to solar + gas.
Unfortunately, the new piping to get the water from the ground floor up to the roof, 7 storeys above to run it through a new solar system on the roof was not feasible. This also would have added additional water pumping costs to our energy bill.
Instead, we are going to invest in a new roof to put over out outdoor boilers to extend their life. With each of the 3 boilers costing $11k to replace it is an important piece of infrastructure which we need to protect.
The problem we face is rising gas prices in the state of NSW.