Frequently Asked Questions
The estimated lifetime of a PV module is 30 years. Furthermore, the modules' performance is very high providing over 80% of the initial power after 25 years which makes photovoltaic a very reliable technology in the long term.
Most manufacturers in general propose
performance guarantees on the modules after 20 years of 80% of the
initial output power. On the electronic components and accessories
(inverters), the guarantee usually does not exceed 10 years.
The electricity production of a PV system
depends on external (environmental conditions) and internal (technology,
layout of the system) parameters.
Shadows on the modules (also if they appear only at certain times of day) reduce significantly the gain of the whole system and should be avoided.The map below represents the yearly sum of global irradiation on a horizontal (inclined) surface. Alternatively the maps represent solar electricity [kWh] generated by a 1kWp system per year with horizontal (or inclined) modules.
To determine the PV electricity generation potential for a particular site, it is important to assess the average total solar energy received over the year.
The size of solar system you need depends on several factors such as how much electricity or hot water or space heat you use, how, the size of your roof, and how much you're willing to invest. Also, do you want the system to supply your complete energy usage or to supplant a portion of your higher cost energy usage? You can contact a system designer/installer to determine what type of system would suit your needs.