Vacuum Tube Technology is the key component of NuPower Solar Systems and is the world's most efficient system for converting the sun's energy into hot water (see comparison diagram below). The technology has successfully been used
in the USA, Europe and Asia for 20 years and works even in extreme cold, low sunlight or cloudy conditions absorbing up
to 93% of the sun's energy.
HEAT PIPE
SELECTIVE
COATING
OUTER TUBE
INNER TUBE
NUPOWER USES 2mm THICK
GLASS TUBING
WITHSTANDS HAILSTONES UP TO 30mm
A vacuum tube consists of two glass tubes made of high impact glass [similar to Pyrex] fused together. The space between these two tubes
is an hermetically sealed vacuum which insulates the tube against
heat loss. The inner tube is coated with black selective coatings [heat absorbent] on the outside. These coatings absorb solar energy, and inhibit radiative heat loss. A heat pipe transfers the heat inside the
tube directly to the water through the condenser at the end of the heat pipe. This condenser can reach a temperature of up to 400°C.
NuPower uses a glass tube thickness of 2mm [compared to 1.2 and 1.6mm]. This added quality provides extra
strength against storm damageand can withstand hail stones up to 38mm. Our tubes are guaranteed for 20 years,
however, in an extreme case where there is damage, we need to replace only the broken tube, and not the whole system.
This diagram shows the advantage of vacuum tubes against flat plate collectors. Vacuum tubes can absorb solar energy even in early morning and late evening. As the sun's rays move during the day, the efficiency of the tubular design stays constant, whereas the flat panel is fully efficient only during peak sun hours. The efficiency curve remains constant even under –7°C and absorbs solar energy.
FLAT PLATE SOLAR HEATING only operational 12h00 - 14h00
VACUUM TUBE SOLAR HEATING always a 90° ray on the tube thus full efficiency at any given time during the day
