On Tuesday, December 16, 2014 10:26:03 PM UTC, Dennis@home wrote:
On 16/12/2014 18:48, wrote:
Interesting feedback thanks. Obviously not a good idea is the general consensus.

Just as a matter if interest I thought Id run these figures by and see if I can get a
clearer picture... My electric storage heater uses 12kwh a night on cheap rate
night tariff. (Thats 85 p/night) That gets it nice and hot.
Im trying to calculate how many panels would give me the equivelent of
12kwh mains a day...so...

In winter a 2kW array will give you less than 1 kWhr if its cloudy and
about 1.5 kWhr if its sunny.
In summer its about 2kWhr and 10kWhr for the same array.

The same area of thermal panels will give you about four/five times as much.

With solar thermal you get a lower grade heat from flat panels than from
evacuated tubes. The same amount of energy if the store is cold enough
to make use of the lower grade.

From a cot point of view you should have solar PV fitted as the fits
will pay fo it and return a profit. Then fit an immersun or similar to
heat during the day when power is available.

Flat panel solarthermal yield much more than tubes per area and per pound when heating cold water (and only when heating cold water).


NT