Green roofs are one of the latest trends in sustainable building, and for good reason: they substantially improve energy efficiency (they can reduce heat loss by 34% in the winter lower heat gain in the summer by 84%), and also clean the air through photosynthesis, by absorbing CO2 and producing oxygen.
So it only seems natural that someone would take the green roof concept beyond the buildings, and now a landscape artist from Spain has done just that. The “Phytokinetic” bus, designed by Marc Grañén, puts the type of green roof you’d expect to see on a building on top of a city’s public transportation. As the bus drives around the city, the green roof absorbs CO2, produces oxygen, and also increases the efficiency of the bus’ travels by reducing the amount of air conditioning that has to be used to keep its patrons cool on hot days.
And though you may suspect that the additional weight of the plants and soil would make the bus less efficient, Grañén compensated for that by replacing traditional plant soil with hydroponic foam, and a coating that doesn’t hold water.
So how do the plants stay watered? Fast Company explains:
The garden is watered using condensation drawn from the bus’s air conditioning conduits, which are sandwiched between the ceiling and the plant bed. A stainless steel mesh anchors the foliage so there’s no risk of it spilling over the sides of the bus or onto its front windshield should the driver makes a sharp turn or hit the brakes.
What do you think about this new environmental twist for a city’s public transportation – are the perceived benefits worth the investment?
Personally, I think it’s a great idea, if for no other reason than it wakes people up to the realization that even a small change can have a big impact. The amount of oxygen being produced by a few green roofs on buses isn’t going to have a world-changing impact, but it will certainly make people stop and think about their carbon emissions, and how they can effect small changes in their life to better the environment.