2) Will it work Here?
- Is my site free from shading?
- Is Snow an issue?
- Will Hail damage solar modules?
- Is the slope or angle of the roof important?
- Do I need a south facing roof?
- Will the PV mounting system damage my roof?
Is snow an issue?
Snow is an issue in the winter months, but it typically melts quickly because the modules are positioned towards the sunlight and the module angle allows the snow to fall away.
Production in the winter months is also at the lowest point in the year so most people don’t worry about removing the snow. However, if you want to remove the snow you may want to purchase a snow rake. Snow rakes can have several telescopic sections that extend your reach.
Isn’t it too cold for solar PV systems?
No, in fact solar PV modules actually work better in cooler temperatures as the voltage increases.
Is it worth the effort to remove the snow?
This is a common questions and when you are first introduced to solar PV you might ask why you won’t remove the snow. Many people do remove the snow, but if your decision is based on economics consider the following.
A small array was set up on the rooftop of NAIT located in Edmonton to test a number of assumptions. The NAIT array has twelve solar PV modules installed in pairs at commonly utilized fixed angles (14°, 18°, 27°, 45°, 53°, and 90°). The snow was cleared only from one of the two modules pairs. The difference in production levels in the winter months in year 1 (year 2 is shown in brackets) between modules angled at 53° was negligible at 2.9% (6.3%); however, the difference between modules pairs at 14° was 21.3% (19.5%).
The actual difference in kWh generated from the six month period between October 1st and March 31st in year 1 between modules angled at 53° was 3kWh (8kWh); and the difference between modules pairs at 14° was 14.1kWh (15.6kWh).
To put this in perspective, the value of 15kWh @ .10 per kWh is $1.50 per module. Therefore, if your system had 20 modules and the slope was 14° clearing the snow for 5 months would generate an extra 300 kWh or $30.
Another consideration is the amount of yearly CO2 offset. In Alberta this can be calculated by taking the number of MWh and multiplying by 0.65; thus, 0.195 tonnes would be removed from the atmosphere (0.3 MWh x 0.65).
For questions or comments on the “Is snow an issue?” section please send us an email to: CustomerService@ensegs.com