Solar Hot Water System Comparison: Flat plates vs. Evacuated Tubes
If you have decided to invest in a solar hot water heating system, it
is time that you begin to consider the type of system you want – a flat
plate solar heater or an evacuated tube system. It is important that you
make an informed decision, keeping in mind your needs and the climatic
condition of the place that you live in.
What are flat plate collectors?
The flat place collector is the only type of solar heating system
that was previously available to people. This system consists of an
insulated box with a glass on one side and a copper tubing that runs
through the absorber plates. They are often connected to a water storage
tank on the roof.
What are Evacuated tube collectors?
Evacuated tube systems are comparatively new in the solar water
heater scene. They use a glass tube with vacuum inside and copper pipes
that run through the centre. These copper pipes are all connected to a
common manifold. This manifold, in turn, is connected to a circulation
pump that keeps pumping water to the storage tank below. This entails
that you will be able to get warm water throughout the day and even at
night.
Think of the evacuation system as a thermos bottle. Just like a clear
thermos bottle would allow in sunlight and then the vacuum would hold in
the heat, the mini tubes in the evacuation system has the same function.
Which one should you prefer?
With knowledge of how the two water heater systems work, you have to
decide which system will be the best for your home. Your decision should
be influenced primarily by the location of your home. If you live in a
place that does not receive a lot of direct sunlight, you should most
certainly choose the evacuation tube system.
The evacuation system is more effective in the sense that it can extract
more heat out of the air, even on a humid day. You will not require
direct sunlight to heat the water. The unique system by which the
evacuation tubes work, make it more efficient even when the sun is not
shining in an optimal angle. In addition, you may face less trouble with
an evacuated tube, since it is less prone to accidental damage.
Flat plate heaters are big and bulky and are harder to install. However,
if you are taking the service of a professional installer and not doing
the job yourself, this should not be an issue for you.
Both the heaters require frame to be attached to. However, installing
the various tubes of the evacuated heater to the tilt-frame will take
slightly longer.
If you live in a place that is mostly affected by a windy weather, you
should avoid the flat plate solar heater. This is because the surface
area of the uninsulated glass of flat plate is more.
The flat plate panels melt the snow because of the high amount of heat
loss that takes place due to the uninsulated glass. However, the
insulation of evacuated tube ensures that there is not much heat loss.
Thus, if your south facing roof does not routinely melt the snow during
a typical winter, flat plates should be a better choice. |
