In message , John
Rumm writes
On 30/04/2019 08:15, wrote:

How realistic are the manufacturers claims for energy produced by
their solar pv panels. If they claim 2kw howlikel is this to be
true/realistic ?

Its likely to be a true reflection of the maximum power delivery of the
panel when in full midday sun in the summer.

In peak summer you might get a load factor as hight as 20% in the uk.
In the winter it will be down in low single digits. Averaged across the
year its usually estimated to around the range of 10% - 12%. Also peak
delivery never aligns with peak demand.

Hmm.. My grazing tenant is considering solar PV panels for an unattended
cattle watering set up.
12V bilge pumps seem readily available and adequate for the head and
flow required. Lead acid battery not a problem but...
how much panel do you need for Hertfordshire sunshine May to October?
Hot weather conveniently requires more water which, last summer, was
around 600litres/day at a head of around 5m.

My mathmatical capabilities do not stretch to this sort of problem:-)



--
Tim Lamb