In stark contrast to some statements seen here, in parts of Europe it is a big trend even for non-electricians to put 1 or 2 photovoltaic modules to the balcony or elsewhere with an on- grid converter. Those are plug- and-play- systems which are easy to install via a connection to the 230V net.
Feed back into the grid is economically useless since the additional costs (an additional or special meter is needed to be rent from the power company, tax declaration needs to be considered, feed-in fee is only 30% of the feed- out fee ) are not worth the feed-in fee.
A typical system with two Trina HoneyM 335 Watt modules and a Micro inverter Envertech EVT-560 incl. cables and special wall outlet, but without mounting system costs 600 Euros.
There are also special offers with older 300W modules for 500 Euros.
It is recommended to adjust one module to South-West and the other to South-East to optimize the match power consumption - power generation.
With electricity costs of 0.30 Euro per kWh and complete DIY-installation, those "balcony power plants" can have an ROI of under 10 years.
Some users who can adapt the homework to their systems to some extent (sunshine day = washing day, vacuuming day etc. ) report an ROI of only 5 years.
Warranty time is normally > 15 years, often 20 years and more.
Of course, power supply companies are not amused by this trend and are sometimes giving doubtful or wrong information about the technical possibilities or legal situation.
Although not in English, there are tons of information in some facebook groups, f.e. https://mobile.facebook.com/groups/644592795726938_rdc=1&_rdr.
EDIT: This is a question from 2014, when the equipment was not yet available (micro converters) or was still too expensive.