VATICAN CITY — And then there was light — and it was powered by the sun. The Vatican on Wednesday activated a new solar energy system and announced an ambitious plan that could one day make it an alternative energy exporter. The massive roof of the ‘Nervi Hall’ where popes hold general audiences and concerts are performed, has been covered with 2,400 photovoltaic panels to provide energy for lighting, heat and air conditioning. After weeks of tests, the system went on line at full throttle hours before Pope Benedict held what officials called the ‘first ecological general audience in the Vatican.’ The new system on the 5,000 square meter roof will produce 300 megawatt hours (MWh) of clean energy a year for the audience hall and surrounding buildings. The 1.2 million euro ($1.6 million) system, devised and donated by German companies SolarWorld and SMA Solar Technology, will allow the 108-acre city-state to cut its carbon dioxide emissions by about 225 tons and save the equivalent of 80 tons of oil each year. ‘This is a very courageous initiative,’ said Carlo Rubbia, the Italian who won the 1984 Nobel Prize in physics and attended the unveiling […]