Urban Oases Combine Roof Gardens and Solar Panels
Sourced from BBC News
The garden feels like an oasis amidst Vienna's densely packed buildings.
It's a demonstration project by Vienna's University of Natural Resources and Life Sciences (BOKU), to show how a green roof can be combined with solar panels while preserving the feel of a garden.
In this case the solar panels are suspended 2m above the garden on a pergola. The semi-translucent panels allow light to reach the garden beneath, while still providing shade to the people sitting below.
Such gardens are valuable in cities where open space is at a premium and a green roof is more than just a flat roof with a few pot plants.
They have several layers of materials, providing sealing, drainage, filtration, soil and vegetation. The benefits are abundant: they can cool roof surfaces, retain rainwater, attract varied animal species, and of course create a more pleasant atmosphere.
Some are walkable, with solar panels suspended high above the garden. On others the panels are placed low down, or even at the ground level.
Given the demand for renewable energy, it makes sense to combine the garden and solar panels into a biosolar roof and in some ways the two functions complement each other.
The cooling effect can boost the performance of the photovoltaic (PV) technology. And the soil or other substrate for the plants can provide the weight to anchor the panels.
But these biosolar roofs face many technical challenges.
The plants may grow too tall and cast too much shade for the solar panels to work effectively. Conversely, the panels may limit sun or rain from reaching the plants. And maintenance of these disparate elements can be difficult.
But designers have been working on addressing these obstacles. Solutions will vary depending on the context.
From the Living Architecture Monitor
