A project studies renewable electricity generation on motorways

CIRCE, Ferrovial and CI3 have brought together in ESPHERA the most promising technologies that may make it possible to use the conditions found on these roads to produce energy
As well as sun and wind, other energy sources such as the flow of traffic and electromagnetic and luminous radiation have also been studied
CIRCE has concluded work on this project to study the feasibility of integrating different types of renewable energy on motorways.
The ESPHERA project – Study of Systems to Produce and Harvest Renewable Energy on Motorways – has carried out a theoretical analysis of different technologies that would allow these highways to generate their own electricity to supply lighting systems, toll points, etc. To this end a selection of the most promising technologies has been made, taking into account financial criteria, efficiency, sustainability and environmental impact. Other factors have also been considered such as ease of installation, resources required for putting them into operation, and technological readiness.
In addition to analysing existing and established renewable energy sources, such as solar photovoltaic, wind and geothermal power, the more innovative systems on the market have also been investigated. Of these, the concept that has raised most hopes is the Vortex, which consists of a post that oscillates with the wind and generates electricity thanks to a set of magnets.
Among the other systems studied are some that capitalise on the force that vehicles exert on the ground as they pass to obtain electricity, for example the i-BUMP, which utilises a speed-bump mechanism, or the SRECC, which obtains energy from the movement of a liquid.
On a different tack, the project has studied a way of gathering the residual energy present in the atmosphere to produce electrical energy (known as “Energy Harvesting”) which may then be stored or used to feed low consumption systems.
The value of this technology lies precisely in its ability to use the resources produced by vibrations, temperature gradients, electromagnetic radiation, illumination and the like to supply low consumption equipment.
Among its findings, the project has concluded that traditional renewable technologies are still the most efficient for these purposes due to their readiness level, especially for relatively high consumption applications, such as motorway service areas. Additionally, it has highlighted the desirability of combining different technologies in what are known as hybrid systems, in order to improve the efficiency and results of the installations.
A theoretical model has been produced from the data obtained taking into account different meteorological variables, which will help study the feasibility of installing these energy systems in new projects.
The ESPHERA initiative has been financed by the Centre for the Innovation of Smart Infrastructures (C13), founded by Ferrovial, the Castile-La Mancha regional government and the University of Alcalá. Ferrovial is also in charge of technical coordination for ESPHERA, which has benefitted from the collaboration of Cintra (the motorway subsidiary company of Ferrovial) and the Aravía company, who hold the concession for the maintenance of the section of the A-2 motorway between Zaragoza and Calatayud.