Law was passed in early 2015 about new buildings requiring solar panels or plants on the roof.
According to this article published by The Guardian in March 2015, France passed a law saying all new rooftops needed to be covered either by solar panels or plants. The solar panels allow energy to be stored giving more renewable energy to the city, plants have multiple beneficial effects to being planted on the roof. While a solar panel may store the suns energy, the plants on top help to insulate the building-keeps cool air in during the summer and hot air in during the winter. Another benefit is the retention of rainwater, which helps to reduce runoff from storms!
Solar panels are a growing resource, more and more buildings are starting to install solar panels on the rooftops and sides. Originally when I first heard about solar panels being installed on residential buildings the price was estimated to be around $10,000 for a small system. Now, a small system that could help reduce the energy bill from the electric company can be reduced by a small solar panel system. Other technologies are being developed to help reduce the use of fossil fuels burning a hole in the atmosphere-literally.
Electric car company, Tesla Motors, has taken a step away from solely producing electric cars but as an accessory, has developed a "super" battery to run your home electricity on, plus charge your car. Tesla's Powerwall has multiple battery capacity sizes but Tesla is saying that even the smaller one will be more than enough storage to run an average size home storing energy during the day and relying on the battery during the night. Here's a short video summarizing the powerwall:
Also, Elon Musk, the CEO of Tesla, decided that the battery was so important that instead of patenting it, he's allowing other companies to copy and remake his technology so that other major companies can create more environmentally friendly technology.