Solar Hot Water FAQs

Evacuated tubes are generally more efficient, and will definitely perform better on cooler and cloudy days. Having said that however, the factor that has the biggest impact on the efficiency of your hot water system is the tube/collector to tank ratio. If you have a large tank and only 1 collector or 20 tubes, then the system is going to operate inefficiently, meaning that you will have to rely on the “boosting” capabilities of your system.

Instantaneous gas boosters have different capacities. A gas booster with a capacity of “21L/min” is capable of heating 21 litres of hot water per minute, provided there is sufficient water pressure. Similarly, a gas booster with a capacity of “26L/min” is capable of heating 26 litres of hot water per minute. How much hot water do you need per minute? The average showerhead uses 9 litres of water per minute, so a 21L/min booster is good for 2 showers at once (provided there is enough water pressure).

Stainless steel tanks will last longer than a conventional glass-lined tank (most stainless steel tanks come with a 15 year warranty). However, they are generally 25% more expensive than their glass-lined equivalents. The biggest factor on the life of tanks is water quality. Provided the water quality is good, there is no reason why a glass-lined tank won’t last as long as a stainless steel tank. Keeping your tank out of the elements can also help to prolong its life.