Given a clean slate a solar passive approach to heating would be taken but when renovating this luxury doesn’t always exist. Solar air heaters allow you capture the suns energy from the roof or external wall of your building and direct it inside.
To make use of solar air heaters you need a sufficient area north facing roof that is not shaded during winter to mount the collector.
A solar air heater is never going to generate the volume of heat of central heating system and it can only run in the middle of the day unlike electricity/gas based systems. Making solar air heating work most effectively means you need some thermal mass to store the warmth you collect during the day, ensuring you have adequate insulation across roof/walls/floor and checking your draft proofing.
I choose and installed two of the SolaMate units. I installed both units myself, each over two easy days on my own. The installation instructions we thorough and easy to follow. You need to be a reasonably confident handy man to tackle the installation yourself.
Through autumn and spring we get at least 80% of our heating from the SolaMate, our roof is shade compromised in winter but we still get a couple of hours during the middle of the day. One of the greatest benefit is the fresh air during winter which simply couldn’t otherwise get.
As they use a very small amount of power we tend to leave them on heating made at the maximum temperature in cool weather making the most of any available heat. It’s a very much set and forget. The control panel lights up when the fan as active so it’s easy to tell from a glance when it’s running and turn off any supplementary heating.
Summer cooling is not as noticeable as the winter heating due to the reduced temperature difference. On a 15 degree day we can get 40 degree air coming in through the vents – a 25 degree increase. After a hot summer day inside temperatures might creep into the mid to high 20’s inside but the outside temperatures not dropping much past the high teens. At best there’s usually only a 10 degree difference available. That said – the gentle movement of cooler air is noticeable – especially when sleeping.
My installed cost was around $3700 per panel.
Over the Solarventi – Australian made, significantly higher air flow volumes, summer cooling capacity.
Over the Smart Breeze – regardless of filtering I didn’t want air from my roof cavity being pumped into my house.
- Australian designed and made product
- Roof mounted solar collector
- 3m x 1m or 1.2m x 2.5m size panels
- Each panel caters for up to 100 sqm of floor area
- Can be mounted flat on the roof or via an elevated frame
- In addition to heating the unit exhausts hot air during summer to cool the house.
- Air flow is provided by an efficient low wattage (80W) fan
- For more information see the SolaMate website
- Originating from Scandinavia
- Primary focus is on providing dry, fresh air from outside to maintain indoor air quality with a secondary focus on heating
- Powered via an integrated photovoltaic panel
- Models available for floor areas ranging from 20 to 140 square metres
- For more information see the SolarVenti website
- Designed and made in Australia
- Roof mounted box
- Uses filtered hot air from the roof cavity for heating
- Can also purge hot air from the roof cavity or suck in cool air from outside for cooling
- For more information see the Smartbreeze website