Please read carefully - important for understanding under floor
heating:

If 160 Watt/m² floor heating is fitted in a room with floor tiles, the
heating only consumes 160 Watt/m² during the warm-up period, e.g. from
18°C to the target floor temperature of 24°C.

At 160 Watt/m² rating this is of course correspondingly faster than
120 Watt/m² - and you save time in the warm-up phase.

Subsequently the floor heating, i.e. from the surface of the floor
tiles, only releases approx. 10 Watt/m² heating power into the room
for each degree Celsius warmer than the room itself.

Roughly half of the heat is released into the room in the form of
infrared heat, i.e. radiant heat.

If the temperature in the room is 22°C and the floor is 24°C, the
floor heating would then only release 20 Watt/m² into the room.

If the room is warmed e.g. by the sun to 24°C, the floor heating will
release no more heat at all into the room and therefore not consume any
more electricity. This is the self-regulation effect of floor heating."

The high percentage of radiant heat in underfloor heating means that
the room temperature can easily be turned down by several degrees to
e.g. 20°C, and it will still be perceived as pleasantly warm.

A floor temperature of 21°C is felt as warm (the emphasis here is on
the feeling of comfort created by under floor heating - the prime
source of heating is e.g. radiators).

In this case the floor heating would only release 10 Watt/m² into the
room.

With a heating area of e.g. 10 m² and a rating of 10 Watt/m² this
would result in electricity costs of 15 cents for 10 hours at a price
of 15 cents/kHz.
This assumes adequate thermal insulation beneath the floor base.

In an extreme case, a 160 Watt/m² floor heating system would heat a
room from 20°C to 36°C (i.e. one degree per 10 Watts) if it were not
limited by the thermostat to approx. 28-29°C.

If the floor plate is thick enough, e.g. 8cm (e.g. heating base from
Knauf) and if the customer has access to suitably low-cost storage
heating electricity, it is also possible to heat an entire apartment or
individual rooms with night storage underfloor heating. The investment
costs are relatively low. If the intention is to use the underfloor
system as the main source of heating, it is important to use low-cost
night storage current.

The consumption costs: i.e. one litre of heating oil provides 10kW/h of
chemical energy although only 80-90% is actually used as heat in the
flat (boiler, radiation and chimney losses). In the case of
electricity, however, 100% is given up to the floor surface. And there
are no costs for chimney sweeps, boiler maintenance or fume emission
measurement.
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