The number of cars on the world's road is rapidly increasing: hitting nearly two billion vehicles in the next 35 years according to the International Energy Agency.
With extra cars come extra emissions. One French company, Ouicar, is looking to transform the way we hire cars with a peer-to-peer car-sharing scheme.
"Ouicar was set up in 2012 on the basis of a simple observation: France's 30 million vehicles, which cost each owner around 6,000 euros ($6,615) per year," Benoit Sineau, chief operating officer of Ouicar, told CNBC's Sustainable Energy. "On the other side, you have people who want to hire, around 10 million per year in France," Sineau added.