Maybe Samsø started a trend in becoming a net exporter of renewable energy because it appears that the Vatican is thinking about doing something similar.  The curvaceous roof of Paul VI Audience Hall, a building that's located right by the famous St. Peter's Basilica, has been topped with 2,400 photovoltaic panels to source energy for lighting, heat, and air conditioning. 

The 5,000 m2 (54,000 sf) roof will produce ~300 megawatt hours of energy and cost approximately $1.6 million (donated by SolarWorld and SMA Solar Technology).  With the addition of this massive solar roof, the sovereign city-state will cut CO2 emissions by about 225 tons.  But that's not all:

According to Reuters, Cardinal Giovanni Lajolo, governor of Vatican City, mentioned that the Vatican was considering the possibility of a solar energy system on ~740 acres of land known as Santa Maria di Galeria, a plot located just north of Rome.  The Vatican-owned site is currently used as a transmission center for Vatican Radio, and if installed, the system could produce six times the amount of energy needed to power the transmission antennas.  The remaining power would be transferred to the Italian national grid for use by surrounding communities. 

Although it's important to stress that this is only an idea right now, going through with it would make the Vatican a net exporter of alternative energy.   

In the meantime, the Vatican is working on the installation of enough renewables to provide 20% of its needs by 2020.  You'll note that this emphasis on renewable energy coincides with the recent publication of a list of additional deadly sins.  Pollution, or ecological offenses, was front and center on that list.




[+] Vatican unveils ambitious solar energy plans [Reuters]
[+] Vatican installs huge solar panel energy system [Telegraph]

Image credit: Reuters