Evacuated Tubes

Flat Plate Collectors

Because of the circular shape of the evacuated tube, the sunlight is perpendicular to the tube for most of the day.

Flat plate collectors provide peak energy output at midday when the sun is perpendicular to the collector’s surface.

Averaged over a year, evacuated tube collector heat output is between 25% to 40% greater that a flat plate collector because the vacuum tube technology minimises heat loss.

Flat plate collectors produce similar heat output in summer conditions, however perform poorly during winter months due to heat loss.

Evacuated tubes are resistant to corrosion. 

Flat plate collectors are prone to corrosion problems.

Evacuated tubes are not easily broken however if one does break replacement tubes are inexpensive and easy to install.

If a flat plate collector panel is damaged the whole panel may need to be replaced which is very expensive.

No water passes through the tubes so any damage will not result in water leakage or interference with the integrity of the system.

Damage to the flat plate collector could result in water leakage and the total loss of hot water. Repairs are both expensive and time consuming.

The system is easy to install and the low weight to size ratio eliminates the need for roof or structural modifications.

A flat plate system collector area is often quite heavy and may require an engineer’s report prior to installation.

Evacuated tubes are hail resistant and will not freeze in frost conditions.

Flat plate systems require expensive antifreeze systems to be installed in frost prone areas.

Modular design allows airflow and eliminates any debris or moisture build-up between the roof and collector.

Debris and moisture build up created by the flat panel design can create problems and could void roof warranties.