Solar wind
Localization: Scilla/Bagnara
Year: 2011
Project Team: Francesco Colarossi (Team manager), Luisa Saracino, Paolo Colarossi,
Engeenering support: 3TI Progetti Italia
2nd PLACE at the International Competition SOLAR PARK SOUTH
Solar Wind is a hybrid (wind/solar) system composed by a wind energy plant integrated with the existing structure of the “Costaviola” viaduct between Scilla and Bagnara and by a carriageable surface covered with photovoltaic panels. Almost ten kilometres of the A3 motorway (from Salerno to Reggio Calabria), between the municipalities of Scilla and Bagnara, will be dismissed after the construction of a new route. This route will be built mainly in tunnels, in response to the need of a safety intervention and a functional modernisation of the present road, as well as taking into account the needs of the controversial project of the Messina Channel crossing.
The original route was mainly built between the 60s and 70s and it features massive and daring works (viaducts and tunnels) for that time, well represented by a series of elegant viaducts designed by Nervi, Zorzi and Morandi, offering spectacular views over mostly intact terraced agricultural landscape on one side and a beautiful view over the sea of the Calabria coast, the Channel, Sicily and the Eolie Islands on the other. Rather than demolishing completely the old route, including the extraordinary concrete viaducts, yet fully integrated within the landscape and the collective imaginary, this old route could experience a second life. Some of the bypassed routes will be reused and equipped in order to promote energy production by means of renewable sources and experimenting new eco-friendly technologies. Therefore, the connections between villages of the area and the access to many valuable crops will also be preserved. Nonetheless, the second life of these routes will promote new ways of making environmental art and land art, which will be functional to the creation of a more responsible type of tourism.
In 2010, over 750 architecture firms from over 50 countries attended an International competition of ideas called “SOLAR PARK SOUTH” and our firm was very proud to win the second prize. The International competition “Parco Solare Sud” held by the Calabria Region for the requalification of the Scilla-Bagnara route within the Salerno-Reggio Calabria motorway, was the occasion to reconsider the function of the existing infrastructures: the viaduct, other than being just a transport mean would have an even more significant duty producing energy. Rather than spending 40 million Euros (that’s the estimated cost of the environmental retrieval) for the demolition of these dismissed routes, the disposal of rubble and landscape restoration, the same amount of resources (or either part of it) could be used for the requalification of the entire infrastructure, as well as of the territory they cut through.
The winds that constantly blow through the valleys where the viaducts stand, would be used to produce clean energy: the empty spaces between the pylons that hold the carriageway would be filled with an organic and attractive element featuring wind turbines. This idea follows the intention to create a new concept of wind and photovoltaic fields, which inevitably have a deep visual impact on the natural landscape. Therefore, the integration of the turbines within an existing structure allows avoiding the exploitation of natural areas that are still immaculate. Furthermore, as the chapter regarding structural feasibility will explain in detail, the project would also allow the viaduct to improve from a static point of view. The “Solar Wind” project, in addition to the integration of the wind turbines, includes solar panels and tapping elements along the road surface. The carriageable road surface will be substituted by a technological type of asphalt (Solar Roadways, produced in USA), which is covered in photovoltaic cells, while the internal carriageway will become a completely pedestrian route, enriched by equipped panoramic spots and solar greenhouses. Public and private sector should ideally manage the route together. Private companies (energy and trading) should take on all costs and benefits and public agencies (Region and ANAS) should host them. Such virtual scenario highlights the importance of social issues and suggest a different use of the route, as more than a merely public system of “common spaces”, because private and personal histories are able to produce important sharing occasions. The functions of the route are intentionally not very detailed, in order to allow the installation a certain grade of fortuity, which makes architecture very similar to life.
WHY?
Inexhaustible energies are the safest energy source for Humans and Nature, although there are two huge problems that still limit their maximum exploitation: the costs/benefits ratio and the relation with the context (natural or anthropic landscape). As architects and planners, our main goal is to tackle the second issue. Solar Wind is a sustainable way to produce energy from renewable sources. Fourteen turbines, a 15 MW system that could produce 22.500 MWh/year, enough to meet the energy requirements of five thousand families. It must be emphasised that the “attractive vision” proposed matches the figure of a “renewable engine” that will start a virtuous circle on an environmental, energetic and economic point of view. Involving local producers and investors would also give an important contribution to the region’s economy, though the actual positive outcomes would surely be much wider.
HOW?
The support structure of the wind turbines has been conceived as a ring structure partly hanging by a frame inserted between the piers of the viaduct and partly in mutual contrast between the rings theirselves. The support structure of the wind turbines is made of ring elements positioned within the viaduct’s spans. Such elements follow an architectural and functional design in terms of energy production return and will be placed in order to distribute tensions partly on the side frame and partly straight into the ground through the adjacent ring structures. Such a complex behaviour needs a deep investigation of structural issues on both global and local levels. The first stage of the investigation focused on the behaviour of ring structures, in order to be able to determine the dimensions and typology of the beam, as well as the amount of abutments needed to hold down the strain and to reduce the dimensions of the elements’ sections. It must be emphasised that the new structure, which will be built on the piers of the existing structure, will contribute to the static nature of the old viaduct, providing static and seismic adjustments which the viaduct inevitably needs after so many years, no matter how well built. In order to perform an evaluation of the wind energy plant’s profitability, in terms of annual production of electric energy, the costs of the project were roughly calculated and separated (cost of structure and cost of turbines). The steal structure, which has a total weight of 8.300-8.500 tons circa, would involve an investment of around 25 million Euros. The wind turbines, considering a 15 MW plant and a cost of 1.000 Euro/kW, would involve a cost of around 15 million Euros. The overall cost would therefore fall within the budget (almost 40 million Euros) considered for the demolition of the viaducts to achieve environmental retrieval. The construction of similar implants on other viaducts of the dismissed route between Bagnara Calabra and Scilla could also be scheduled subsequently, involving the research of other financial resources. It must be either emphasised that, considering the present development of the renewable energies’ sector, a wind energy plant is a safe economic investment, in addition to its important environmental value. In order to evaluate the payback period (when an equivalence between cash outflows and inflows occurs) it is necessary to figure a possible profit, which can be determined depending on: > approximate price of energy paid by the National company for energy acquisition (around 0,17 €); > average annual costs for maintenance (around 0,007 €/kWh). Sectoral economic studies outlined that a wind turbine, in 20 years time, would produce an average financial profit of over 3.2% per year, in times of favourable selling conditions, while payback period usually varies between 8 and 10 years.