The idea of blanketing buildings with living plants as a way to mitigate their environmental impact isn’t new, but Vegetal i.D. is adding a couple twists on the so-called green roof concept that company leaders think could shake up the industry. Chief among them: a cloud-based system that could allow the roof to work in concert with the storm sewer system to prevent backups during heavy rainstorms.
Vegetal is the U.S. branch of Le Prieuré, a French company with about 25 full-time staff. Owned by farmer Raphael Lamé, Le Prieuré installed its first green roof in 1989. In 2000 it patented the Hydropack system, which it says marked the first modular green roof in Europe. Since then, the Hydropack—fully grown vegetation and thin water reservoirs packed into stackable trays that can be easily transported and installed—has been put on more than 1,500 rooftops, the company said.
Now the company’s U.S. outpost is spearheading development of a next-generation system that, if all goes according to plan, will be tested for the first time this spring in Milwaukee.
Vegetal launched in 2011 with a plant nursery at a farm in Batavia, NY, and now employs six full-time staff. The main focus these days for two of those team members is a so-called stock-and-flow system that combines the Hydropack green roof with a reservoir, or “blue roof,” and cloud technology to control the flow of water from the reservoir into the storm sewer system.
The green roof/blue roof product won Vegetal a spot in a seed accelerator program for fresh water technology startups in Milwaukee. (Read Xconomy’s stories about other Milwaukee water tech startups, Microbe Detectives and H2Oscore.)
“Technically I’m not a startup, but this product is kind of a startup on its own,” said Gaelle Berges, a France native whom Lamé tapped to run the U.S. operation as its product and development manager. “We’re starting in Milwaukee. Then we want to validate this technology in other climates.”
The vegetation on green roofs absorb rain to reduce potentially harmful runoff; beautifies urban areas; improves air quality; offers a habitat for birds and insects in the city; and insulates the building, Berges said. It’s that first benefit—controlling runoff—that Vegetal is looking to amplify with its green roof/blue roof project.
“A green roof is like a sponge, and it absorbs a lot of water, but when it’s fully saturated it doesn’t retain more water,” Berges said.
Enter the blue roof concept: a plastic tray that acts as a reservoir and can be outfitted with mechanisms to control the release of the captured rainwater off of the roof.
Hydropack can capture 1.1 inches of rainfall. The new system adds an additional 4 inches of capacity with the storage well, plus the ability to purge that reservoir by remote control, said Brennon Garthwait, Vegetal storm water management specialist.
In the spring Vegetal plans to launch a two-year pilot installation on a roof in Milwaukee that ideally will produce data that will convince engineers, roofing contractors, and storm water management agencies of the product’s value, Berges said.
The pilot will test two versions
