Understanding the Technology behind Solar Evacuated Tubes
Solar evacuated tubes have been around since the early 1900s. But solar heating systems are now using solar evacuated tube technology. The solar vacuum tube technology works similarly to a thermos bottle. The technology involves trapping the heat energy inside and providing an insulation barrier, ensuring that there is no heat loss back to the air.
Solar evacuated tubes work effectively in colder climates, especially during freezing conditions. However, Latitude51 Solar provides evacuated solar tube water and pool heating packages. Our solar-powered systems include the SunRain solar vacuum tubes that use a copper heat pipe in the center of the tube.
The solar heat energy is transferred to the heat pipe using specially-engineered aluminum fins. The heat pipe contains a small amount of liquid under vacuum conditions. However, according to Physics, the liquid under the vacuum will boil at a lower temperature. Due to this phenomenon, the liquid inside the heat pipe boils at 30 degrees Celsius (86F) and turns into vapor. The vapor goes to the top of the condenser bulb, where it gets cool by releasing heat through the bulb into the copper manifold and changes its state to liquid that sinks back down the heat pipe.
Understanding the Working Principle of Solar Evacuated Tubes
The solar collector is the engine of any solar water heating system. Solar evacuated tubes have been considered highly effective solar power production systems, but they were more expensive than flat panel systems.
But the increasing demands for solar energy and modern manufacturing technology have cut down the cost so that you can expect the maximum return on investment from the vacuum tube technology than any other solar collector system.
The working principle behind solar evacuated tubes is simple. As discussed above, it works similarly to the coffee thermos. The vacuum tube consists of two glass layers, and a vacuum is between them. The external layer is made from borosilicate glass which is very low in iron and allows 98% of light energy to pass through. The second internal layer has a special coating.
The SunRain solar evacuated tubes use a patented three-layer process, resulting in a coating that can absorb more solar energy. In addition, the tubes can withstand the excess temperature of 300 degrees (575F) without deteriorating. The layer makes the solar collectors stand out from other collectors available on the market.
The special selective coating converts the short-wave solar radiation into long-wave heat radiation, and the system is around 94% efficient, which means only 6% of energy is lost. The absorbed solar radiation gets transferred to the heat transfer fluid within the vacuum tube – the liquid inside the thermos.
The liquid heats up quickly and goes to the top of the tube. In an open vacuum tube system, the potable water is heated directly inside the vacuum tube. The thermosiphon inside the vacuum tube causes the hot water to rise and can be replaced by colder water. The hot water is collected at the top collection chamber and pumped through the system.
Bottom Line –
Do you want to know more about solar evacuated tubes? If yes, then feel free to contact Latitude51 Solar at 1 800 317 9054.