Designing and implementing solar photovoltaic system in secondary residence

The goal of this research was to find out, what kind of further training an experienced electrician or electrical contractor needs to be able to design and implement a 12volts off grid system for residential use. In Finland, installing the low voltage system of 12 volts not necessary requiring qualifications, but anybody is allowed to implement such system. However, if something happens, the insurance company may cause troubles, if the system is not installed by professionals. Despite of this, it is not common at the moment, that a contractor designs and implements such a system. The system was designed to be implemented into two secondary residence owned by two families. in implementing phase It was found out that it is a challenge to find a contractor that would be interested in and capable to implement low voltage systems. In common, contractors are specialized in higher voltages, and they do not necessary have experience, tools and components required in working with lowest voltages. Also the relationship between voltage, current and resistance seemed to be lost. Although the formulas P=UI and U=RI should be known by everyone working with electricity, the impact of distance and current on designing the wiring seemed to be unknown or forgotten. It was found out, that to be able to design and implement low voltage solar photovoltaic system, an experienced contractor without earlier experience on such systems, needs further information concerning the standards and regulations, fire safety, batteries and designing the wirings. This information could be given in further training concentrating on photovoltaic energy systems and special issues in 12 and 24 volts installations.