Solar Water Heaters
A solar water heater uses sunlight directly to heat water, reducing electricity or gas used for bathing and washing.
Two common types
- Evacuated tube collectors (ETC): glass tubes that retain heat well and perform better in cooler weather.
- Flat plate collectors (FPC): a glazed panel, durable and often preferred where water is hard.
Sizing
Capacity is usually chosen by litres per person per day. Hotels and hostels need larger, carefully designed systems with a backup heater.
Cold and hilly areas
In freezing conditions, pipes and tanks need protection. Ask about frost handling before buying.
Installation notes
- Place collectors where they receive unshaded sun for most of the day
- Face them roughly south at a suitable tilt
- Insulate pipes, especially long runs and outdoor sections
- Plan roof load for a filled tank
- Descale periodically if your water is hard
Backup heating
Cloudy days and winter evenings need a backup, usually an electric element or gas. Check that it is wired through a thermostat so it only runs when needed.
Frequently asked questions
Does it work in winter?
Yes, with reduced output on cloudy days; an electric backup element is common.
How is it maintained?
Periodic cleaning of collectors and descaling where water is hard.