While flat-tube collector is reasonable and easy to install, the problem is that they are slightly less compact. This drives a certain restriction to their efficiency as they can be only operated at maximum efficiency when the sun is overhead. Installation of evacuated tube collectors can help solve this problem because it uses individual rounded tubes that respond well to sun rays throughout.
A solar hot water system using an evacuated tube collector allows it to operate more efficiently and retain the temperature for a longer period of time. Also, with ETCs, the limitation of weight and roof structure caused by flat plate collectors are eliminated. Even if it is a bit cold and snowy, adequate sunlight will pass through to preheat the water and ensure cost-saving.
What is an Evacuated Tube Collector?
The evacuated tube collector contains numerous rows of parallel transparent glass tubes integrated into a head pipe and wherein the heat transfer fluid and absorbs the heat produced by tubes. These glass tubes are lightweight, cylindrical, and perform well even when sunlight is low. That’s why it is considered very useful in areas with cold, cloudy, and snowy weather conditions.
It offers combined effects of surface coating and vacuum insulation of the absorbent component that ensures high heat extraction efficiency in comparison to FPCs. At this moment, the glass evacuated tube has become very common in solar thermal usage and are proved to be useful in all applications for higher temperature efficiency.
How does Evacuated Tube Solar Collector Work?
Evacuated tube collectors consist of single or various rows of parallel, transparent glass tubes maintained on a frame. Each tube carries a thick glass outer tube and a thinner glass inner tube that is covered with an effective surface coating to absorb solar energy while reducing heat loss. The tubes are made of soda-lime glass that is reliable, durable, and can withstand extreme temperatures for solar radiation.
Unlike flat plate controllers, ETCs don’t heat the water within the tubes instead, the air is evacuated from the space in the middle of two tubes, producing a vacuum. The vacuum works as an insulator to reduce heat loss either via convection or radiation. With the support of vacuum, ETCs usually produce high fluid temperatures as compared to flat plate counterparts.
The adoption of evacuated tube collectors has significantly grown over time due to its several advantages like reduction in manufacturing costs, great performance in all seasons, and attractive appearance. In comparison to flat plate collectors, ETCs offers a lot of benefits:
- Improved ability to capture sunlight as the surface area is exposed directly to the sun
- More efficient in heat transfer
- Greater durability
- Cost-effective choice
- Superior performance in overcast conditions
- Less prone to corrosion
- Compact design
When you’re switching from electric to solar hot water systems, you can count on Solar Crafts, established with an aim of delivering impeccable solar solutions to limit environmental damage and ensure cost-saving at every step. Contact us today to learn more about evacuated tube collectors and receive a free quote on desired products.