I haven't been here for long. Only a month. But it is long enough to comment on the
climate in Cambodia. This is a tropical country. We have an abundance of sunshine
even in December. However, to my disappointment, I haven't seen any solar heaters
utilizing the sunshine in Phnom Penh. Instead I have seen (at some hotels) electric
heaters. While those imported electric heaters are bought with much-needed hard currency
and are powered with imported fuel, a solar heater can be locally made with local
materials and local labor.
You may think of a solar heater as "a system" made up of a solar panel
and an insulated hot water tank with an electric heater backing it up for a rainy
day, and coming with sensors and automatic this and that. But a simple solar heater
is nothing but a flat water tank placed on top of the roof. The size of the tank
depends on how much hot water you need. A tank can be made of iron, wood, heavy-duty
plastic bag or even brick-anything works as long as it is watertight and remains
watertight. The flatter the tank, the better the heat absorption. Paint the top black.
Fasten a pipe to the bottom of the tank. Such a simple tank can be made by locals
and installed by a plumber or a do-it-yourself-homeowner.
At morning you fill the tank with cold water. At evening you can empty hot water
from the tank. In my experience in Tokyo, water was heated to about 70 degrees Celsius
in an iron tank during summer. Here you can expect comparable temperatures even in
If you are thinking of buying an electric heater, check with a local plumber instead.
Once he gets the basic idea, he can probably make a better solar heater than the
one I have described.