Evacuated GlassTube Collectors combine the high efficiency performance of evacuated tubes with rapid heat transfer capacity of heat pipes to provide a collector that can operate efficiently in almost any climate providing hot water for residential or commercial solar water heating projects
The Key Component of the Evacuated Glass Tube Solar water heater is the Evacuated Glass Tube(EGT). The Evacuated Glass Tube having the best possible insulation (Vaccum Jacket), allows sunlight to pass through, but prevents thoroughly the thermal heat transfer, featuring high efficiency, low heat loss and longer life.
The use of Evacuated Glass Tube Technology appears to be one of the significant progresses in the solar industry all over the world. Now Evacuated Glass Tube solar systems are popular through out the world
Advantages of EGT Solar Water Heaters
- Highest Efficiency – above 80%
- Handles hard water and no scales formation on EGT walls.
- Practically Nil maintenance and very long life(20 Years).
- Elegant appearance, light weight and can be installed easily
- Minimal heat loss – Thanks to EGT Technology
- Superior winter performance and high frost protection
- Available in sizes 100 / 200 / 500 liters per day or by integrating multiples of 500 LPD to suit any applications.
Construction
Operation
Step 1: The absorber coating on the inner glass tube absorbs sunlight and converts it into heat.
Step 2: Steam forms inside heat pipe which transfers heat rapidly up to the manifold.
Step 3: A pump circulates water or heat transfer fluid through the header pipe, carrying heat back to the storage tank. Gradually throughout the day the tank is heated up.
The tank can be boosted by an electric element, gas/oil boiler, or the solar tank can simply feed an existing water heater tank with solar pre-heated water.
Design Advantages
Evacuated glass Tube Efficiency
The vacuum space in the evacuated glass tube greatly reduces heat loss. This greatly increases the conversion efficiency at higher water temperatures or when the outside temperature is very cold.
Passive Tracking The round absorber surface of the evacuated tubes passively track the sun throughout the day, so no mechanical tracking device is required. This allows maximum surface area exposure from 7am to 5pm which covers the majority of the solar radiation each day. The end result is on average around 60% of the total available daily light from sunrise to sunset can be converted into usage heat.
The passive tracking feature also allows the collector to be installed at directions East or West of equator pointing (North or South) without too much reduction in output.