How reliable is solar hot water? Should I switch to solar?

reliable solar hot water heaters

Are you thinking of switching to a solar HWS but wonder “how reliable is solar hot water” or “does solar hot water work when it’s cloudy”? 

In the past 20 years, solar hot water has advanced rapidly and the technology surrounding it is now cheaper, more reliable and has a longer life span.

Does solar hot water work if it’s cloudy?

Even when the sky is cloudy, the sun is still letting off solar rays that heat your hot water. If the sky is blue and the sun is shining, you will have more hot water BUT  it doesn’t need to be sunny and hot for a solar hot water system to work and generate great, free hot water.

Solar boosters and back up systems

Most solar hot water systems have a booster system or back up system which means if your hot water tank isn’t holding enough hot water for your needs that the booster will heat water for you on the spot. A common and popular type of back-up system is a gas or electric instantaneous hot water system.

Making the switch to solar hot water

In Australia, with our temperate climate and sunny weather, it makes sense to try and utilise what Mother Nature provides free of charge to heat your hot water. By using solar energy means you pay less than conventional electric or gas water heaters, whilst reducing harmful greenhouse gas emissions. It’s a win-win on all accounts!

Is my roof suitable for solar hot water?

Roof space

Most houses will use 2 solar collectors which are around 2m tall x 1 m wide each. That means you need at least 2m x 2m, plus some clearance space on your roof.

For a roof-mounted tank, you’ll need even more roof space .

Ground space

You’ll also need some ground space for the ground-mounted hot water storage tank, if applicable. This isn’t necessary for roof-mounted tanks.

North facing roof area

It is best if the collectors can be mounted facing north in order to capture the most sunlight. If you’re not sure, use a compass or go to Google Earth to check if you’ve got a north-facing roof area.


The solar collectors will need to be placed in an area of high sunlight and minimum shade. Shade from trees and surrounding buildings aren’t ideal.

Climate can also be a factor when choosing a solar hot water heater. Extreme weather areas that get frost or very high heat will need a product designed to suit the climate.

If solar doesn’t suit your home then a heat pump system is a great alternative. In the industry we call heat pumps “solar without the panels”.

Types of solar water heaters »


More information about switching to solar

For more information about the cost of switching to solar hot water, contact one of our solar hot water experts. 

Solar hot water is our business – it’s not a sideline like other companies! We are authorised installers and repair technicians for all the solar hot water heater brands including Solahart, Rheem, Edwards, Apricus, Quantum and many more.  Our solar systems are competitively priced because we purchase large quantities direct from the manufacturers – a saving we can pass on to our customers.

For hot water heater service advice