Instruction Manual

PowerOptimal Elon® 100 Installation Manual
Version date: 2022/05/23
Page 20 of 37
Version number: 2.20
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You can expect the following approximate energy generation from solar modules for various
locations
2
:
Location
Electricity generated
kWh/kWp per year
Bloemfontein
2055
Cape Town
1762
Durban
1570
Johannesburg / Pretoria
1871
Mbombela
1766
Port Elizabeth
1698
Upington
2075
B2. Geographic features
Major geographical features (such as hills or mountains) can reduce the total solar yield.
B3. Azimuth / horizontal angle
The azimuth refers to the horizontal orientation of the modules
– in the Southern Hemisphere, by how many degrees they are
oriented away from north
Due north is best in the Southern hemisphere. Modules should
preferably not be oriented more than 15º away from due north.
B4. Inclination or tilt angle
The tilt angle refers to the vertical orientation of the modules – a rough guide is that the modules
should be tilted at the site’s latitude. For example, Musina is 22º S, Pretoria & Johannesburg are 26º
S, Bloemfontein is 29º S, Durban is 30º S and Cape Town & Port Elizabeth are 34º S.
To optimise winter performance, one can add 15º to the tilt angle. (Note: as long as you are within
about 15º of the optimal latitude, the loss in efficiency is not substantial.)
B5. Shading
Solar modules lose a lot of efficiency if even a small part of the module is shaded. For example, just
3% shading can cause a 25% loss in power! Shaded cells on a module also causes hotspots, which will
reduce module lifetime.
It is thus important to place the solar modules on a rooftop area that is free from shading for as much
as possible of the day (and throughout the year).
2
Urban Energy Support. Website:
http://www.cityenergy.org.za/uploads/resource_274.pdf. Last accessed:
07/04/2017.