Nature Based Solutions - Implementation Models Database

Implementation model

Photovoltaic Roof Garden

A short description of the NBS project

As part of EU Biosolarroofs concept, the project Photovoltaic Roofgardens combines previously separated disciplines as green roof construction, building-integrated photovoltaic systems and roof design. Producing renewable energy, offsetting increasing soil sealing, improving the micro-climate, storing CO2 and rain water and extending the life of the roof membrane – a combined roof system should do all this and much more. The aim of the project is to combine these concepts to develop one holistic system. Synergies will be found between areas that have until now competed with each other. For the development of such a holistic concept, the following comprehensive analysis was carried out: understanding of users and users’ needs, coordination of appropriate vegetation systems in combination with PV shading, effects of shading patterns on people, integration and coordination with the architecture, landscape planning, construction and irrigation concepts as well as cost and revenue. These concepts have been tested using demo simulations. The research project’s initial results were presented at BOKU Wien: the plant-filled roof terrace creates a pleasant, comfortable environment. The photovoltaic pergola with semi-transparent glass-glass modules provides shade and produces green energy. The wooden test facility at BOKU does not yet represent the final architectural design. But it is already clear how the solution works: the previously underutilised terrace has become an attractive recreational and meeting place with a noticeable three to five degree temperature difference. In the test garden, five tons of CO2 are saved every year thanks purely to the photovoltaic system, without taking account of the CO2 retention properties of the plants and soil. The plants also act as a fine dust filter. The final design of the photovoltaic roof garden consists of a green roof structure, a pergola made of wood or steel and a canopy with photovoltaic glass-glass modules. A photovoltaic roof garden unit measures around 56sqm and can be endlessly multiplied. It provides about 5.500 kilowatt hours of green energy a year, or enough to supply one to two households. The costs including plants, steel girder construction and photovoltaic system are around €79.500. At €1.400 per square metre, the photovoltaic roof garden costs roughly the same as a conservatory. But for the same price, it provides both green energy and pleasant, green surroundings.

NBS Implementation context
Location Austria, Wien (Austria)
Status Project delivered (2013-2015)
Description of the NBS
NBS Scale object (building, etc.)
NBS Impacts scale • Object (building) • Neighbourhood • City
Urban density/ Soil consumption High (dense city center)
Combined with other(s) environmental friendly solution(s)?
if other
NBS Typology
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NBS Uban Challenges
Climate Issues Climate mitigation
Climate adaptation
Other 0
Urban water management and quality Urban water management and quality
Flood management
Other 0
Air Quality Air quality at district/city scale
Air quality locally
Other 0
Urban Space and Biodiversity Biodiversity
Urban space design
Urban space management
Other 0
Urban Regeneration and Soil Air quality at district/city scale
Other 0
Resource efficiency Food, energy and water
Raw materials
Other 0
Public health and well-being Acustic
Quality of life
Other 0
Environmental justice and social cohesion Environmental Justice: Recognition
Environmental Justice: Procedural Justice
Environmental Justice: Distributional Justice
Environmental Justice: Capabilities
Environmental Justice: Responsibility
Social Cohesion
Other 0
Urban planning and governance Urban planning and form
Governance in planning
Other 0
People Security Control of crimes
Control of extraordinary events
Other 0
Green economy Circular economy
Bioeconomy activities
Direct economic value of NBS
Other 0
Stakeholder and Governance
Who Started this initiative? Community • Research institutions
Contracting Authority
Project manager (leader and main partners): entities names, and know-how involved
Who (else) was involved in the project ? (Inhabitants, local association, etc.)
More detail on the process and the role of the different stakeholders (How did it happen?)
OPTIONAL Considering the actual impacts, who are the primary beneficiaries of the project.
Cluster Governance Model Description
cluster5_network_governanceCollaborative_governanceThis project is funded by the Federal Ministry for Science, Research and Economics and the Austrian Research Promotion Agency. The costs including plants, steel girder construction and photovoltaic system are around €79.500 (€1.400 per square metre).
Global Estimated cost of the project 50k€ - 200k€ (€79.500)
Cluster cluster1_public_financing
FM Public financing
Description of the financing mechanism This project is funded by the Federal Ministry for Science, Research and Economics and the Austrian Research Promotion Agency. The costs including plants, steel girder construction and photovoltaic system are around €79.500 (€1.400 per square metre).
Business Model
Class Type Description
Temporal Factor
Expected time for the NBS to be fully effective after its implementation
Expected life time of the intervention
Already feedbacks on the project? In case, the project has already been adapted to new requisites, please explain the modifications brought
Success and limiting factors
Process Enablers
Class Subclass Type Description
Knowledge_driversGeneration of evidence Collaboration Awareness • Lesson learnt through implemented projects; • Networks; • Climate Change -
Governance_driversProcess efficiencies • Collaboration; Co-creation and participation • Co-production Process efficiencies • Collaboration; Co-creation and participation • Co-production
Process Inhibitors
Class Subclass Type Description
Knowledge_driversUncertainty • Performance unknown
Governance_driversInstitutional barriers • Lack of flexibility of decision making structures
What makes this project a pioneer?
Brief description of the innovativeness
Has the project received a prize, an award?
Has the project received a media coverage? (in reviews, in press, etc.)
IM Keywords