Vacuum Tube Solar Energy Systems

تتكون الأنابيب المفرغة من أنبوبين زجاجيين متداخلين ومفرغين بينهما.
الأنبوب الخارجي مقاوم لجميع الظروف الجوية.
The inner tube is made of a transparent and durable glass with a special composition and is coated with a black selective surface.
Thanks to this surface, 93% of the sun's rays are absorbed and converted into thermal energy.
بسبب الفراغ، تكون خسائر الحرارة في الأنابيب بسبب التوصيل والحمل الحراري عند الحد الأدنى.
تستطيع أنظمة الطاقة الشمسية ذات الأنابيب المفرغة إنتاج الماء الساخن حتى عند درجة حرارة -40 درجة مئوية دون الحاجة إلى مادة مضادة للتجمد في ظل ظروف مناسبة.
لا توجد حاجة لمصدر طاقة إضافي لتشغيل الأنظمة.
يتحرك الماء الذي يتم تسخينه وله كثافة أقل في أنبوب الزجاج المفرغ إلى الأعلى في الأنبوب باتجاه خزان الماء الساخن.

Evacuated tubes are produced from two nested glass tubes.
The outer glass tube is resistant to any type of hard weather condition.
The inner tube is made of a special combination of transparent, durable glass and covered by a black selective coating.
through this selective coating, 93% of sunshine can be absorbed perfectly by tubes ans converted to heat.
Due to the vacuum between two glass tubes, the conducted and convected heat losses are negligible.

The evacuated solar water heaters can produce hot water even at -20C and run regularly without antifreeze with the high thermal efficieny of the vacuum tubes.
There is no need of any power supply to run the solar water heaters.
When the water is heated by the Solar Radiation through the vacuum tubes, density of water is decreased and it moves through above into the hot water tank.

Density of cold water in the tank is higher than hot water, so it flows below the vacuum tubes.
With this relocation of hot and cold water, the natural circulation occurs and the hot water is produced.

The non-pressurized (open-loop) solar water heaters work with natural circulation principle.
The difference between non pressurized and pressurized solar water heaters is presence of the Copper (cu) erpentine.
The mains water is circulated in serpentine. With heat transfer between cold mains water in serpentine and hot water in tank, the cold water is heated.
So, the hot water is produced for usage.