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Extensive Sedum Green Roof. An extensive green roof is a green roof that is less than 6″ thick. As opposed to an intensive green roof that is more than 6″ thick. Because of the thickness of the growing medium an extensive green roof can only support sedum and drought tolerant small plants. The reason for this is the limited root space and the small amount of water the soil can store. Here is a good image of an extensive green roof structure.
Solar-roadway backers set crowdfunding record - CNET
solar panels made into roof shingles by Dow Solar
Next Gen Solar Power Chargers by Changers - Innovative solar energy battery charger made of paper-thin Maroshi solar panel and the Kalhuohfummi battery with multiple socket options for all electronic devices, storing up to 4 watts of energy | MONOQI