Solex Roofing Installation Manual 2
Solex Energy Ltd +44(0)1305 837223 www.solexenergy.co.uk
Overview
Solar roofing offers an alternative to solar traditional solar thermal panels or tubes. Its
main advantages are those of cost, aesthetics, and the ability to provide larger solar
collecting areas on a given roof slope. The efficiency per m
2
is around 80% that of
traditional flat panels.
The output of the solar roofing is heated water, which may be used for hot water, space
heating, pool heating or any other water heating application.
Operation Summary
A solar fluid circulates through black silicone rubber absorber strips on the roof and is
heated by the sun. Solar glazing in the form of glass or plastic slates, tiles or sheets
covers and insulates these strips, and forms the roof surface. An insulation layer behind
the strips also reduces heat loss.
The rubber will cope with freezing conditions, and in overheat situations the fluid will drop
back into a holding tank below. The fluid is circulated by a solar pump/controller unit which
transfers the heat through pipes to where it is required.
Roof Orientation and Pitch
•
The roof to be covered should ideally face south.
•
Orientations from SE to SW are fine with performance around -12% at the extremes.
•
Orientations as far as E or W still perform okay, with performance at around -25%.
Given the choice, and all other considerations being equal, W or SW should be chosen
over E or SE, as ambient temperatures are higher in the afternoon increasing
performance, and also hot water and heating demand is usually higher in the evening.
The ideal pitch is 30
o
to 50
o
for year round performance. Steeper pitches up to 60
o
favour
winter performance which is important for space heating. The slates have a minimum
pitch of 25
o
and a maximum of 90
o
. For pitches under 25
o
or over 70
o
contact us for
additional installation instructions.
Performance
The average annual output (south facing, 30
o
-50
o
) is in the range 400 - 425kwh/m
2
/annum
when used to provide hot water, and somewhat more than this when used to provide lower
temperature output e.g. for space and pool heating. Instantaneous output under full sun is
up to 720w/m
2
.
Use the spreadsheet at
www.solexenergy.co.uk
to calculate roof outputs, energy savings
and system costs.
System Sizing
•
Hot water systems
– the recommended sizing is 2m
2
solar roof/person, with a
minimum size of 6m
2
. The recommended sizing is generally:
Typical 3 bedroom house – 8m
2
Typical 4 bedroom house – 10m
2
Typical 5 bedroom house – 12m
2
