Bold new law requires green rooftops in France

Rooftops in France are going green.

Under a law passed last week by the French Parliament, new buildings in commercial zones must partially cover their roofs with plants or solar panels.

"This draft law is a very positive step forward and a concrete lever for greener and smarter cities," said James Watson, CEO of the European Photovoltaic Industry Association. "There are so many unused rooftops in our cities today and solar photovoltaics is the perfect solution to make the best out of them as it can be seamlessly integrated in an urban setting."

Watson added that rooftops, large or small, represent 70 percent of the installed solar capacity in France.

French environmental activists initially had called for a stricter rule that would require all new buildings to be completely covered with either solar panels or plants, according to Agence France-Presse, but the government convinced them to limit it to only commercial buildings.

Even with the limitations, this is progress for France, which has lagged behind other major European countries like Italy, Germany and Spain in solar power development. Recently, the capital city has embarked on a number of greenifying projects, including adding two wind turbines to the iconic Eiffel Tower.

During summers, green rooftops help keep buildings cool, while photovoltaic cells provide electricity for the remaining air conditioning needs.

"Solar electricity produced on your roof can partially or entirely instantaneously cover your own power needs," Watson said.

The benefits go far beyond cost savings. In 2014, solar energy production saved about 110 million tons of carbon dioxide emissions globally.