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EN
1 DESCRIPTION OF THE APPLIANCE
1.1
Characteristics
The use of forced-circulation solar heating systems allow for
saving up to 70–100% energy, given that the burner in the boil-
er or the heating element works for less time, compatibly with
the zone’s exposure to sunlight and the dimensions of the solar
system installed, with a simultaneous reduction in carbon di-
oxide emissions.
Solar systems are built with premium-quality materials in con-
formity to international standards, and are accompanied by all
relevant certificates and analyses confirming their quality.
Characterised by a modern design, these systems are easy and
quick to install and blend in harmoniously with traditional or
modern architectural styles of buildings, supplying cold water
for free almost year-round.
Even regions that receive less sunlight are guaranteed to have
pre-heated water, which helps to considerably reduce the con-
sumption of conventional energy.
1.1.1
General characteristics
Nowadays it is widely known that we have to produce and save
energy without however polluting the environment. The plan-
et’s conventional energy sources are running out at an alarm-
ing rate while society’s energy requirements increase, gener-
ating polluting agents that threaten the climatic equilibrium.
Renewable energy sources are a possible solution to the energy
problem but also to pollution. International legislation is grad-
ually changing and encouraging – or even enforcing – the use
of alternative energy products with the aim of satisfying energy
requirements without jeopardising the environment.
1.1.2
Domestic hot water requirement
Statistically it has been calculated that a family’s average con-
sumption hovers around 35–50 litres a day per person. If we
add the consumption of the washing machine and dishwasher if
they have been connected to the solar heating system, roughly
20 litres a day are required for each appliance (for one wash).
A family of four, therefore, assuming an average consumption
of 40 litres of hot water each, will need a 160-litre solar water
heater. If we add the household appliances connected to the
solar system, this requirement increases by at least 40 litres a
day. In order to take full advantage of the solar water heater, we
must use as much hot water as possible during the day, so that
the system can produce constantly when there is sunlight while
maintaining maximum performance.
1.1.3
Operation of the solar system - water heating
The surface of the collector, through the solar energy it absorbs,
heats the liquid (water or anti-freeze solution) that circulates
inside the solar heating collector. The heated liquid becomes
less heavy and flows towards the calorifier, heating the water
contained in it. The circulation of the liquid in the collectors is
not forced, but natural (thermos phonic effect).
There are numerous factors influencing the temperature of the
water supplied by a solar heating panel and their values oscil-
late in relation to the season, the time of the day and the place.
Considering that the solar heating panel is a system exposed to
atmospheric conditions, the fundamental parameters that in-
fluence its performance include the temperature of the supply
water, the available solar energy and the outdoor temperature.
The temperature of the mains water does not remain constant
throughout the course of the year, since it is far cooler in winter
than in summer. If we take 45°C to be a satisfactory tempera-
ture for the domestic hot water (for satisfying the needs of a
household), we infer from statistical data that the temperature
of the mains water should increase by 35°C during winter and
by 20°C during summer.
Moreover, the available solar energy does not remain con-
stant during the year, since in winter it is lower than in sum-
mer. When there is a low amount of sunlight coupled with cool
outdoor temperatures, the solar panel ensures pre-heating
and is assisted by the use of the heating element or central
heating boiler (triple-energy systems). Regarding heat losses
during the night, these are minimised by the system’s effective
thermal insulation. These losses naturally depend on the out-
door temperature, which varies in relation to the place and the
weather conditions.
