German energy group RWE AG (ETR:RWE) has installed and commissioned a 5.7-MW onshore wind turbine as part of the Orkoien pilot scheme located near Pamplona, Spain, and successfully tested two technologies to reduce the environmental impact of construction and operations phases of the project.
The company said it had placed removable plastic mats on temporary work areas at the site to minimise the construction-related impact on the soil. These areas, such as access roads and storage sites, are typically excavated and gravelled, but at Orkoien, RWE tried putting special plastic mats on top of the surface that was only smoothed with the excavator in a previous step.
Once the construction is over, these mats can be removed to be used for other projects and the vegetation can regenerate completely, RWE said.
“The plastic mats surpassed our expectations,” commented Robert Navarro, President and CEO of RWE Renewables Iberia. “During the construction of Orkoien we faced harsh weather conditions with heavy rains and flooded soil. Nevertheless, we had secure access roads for the installation of the wind turbine. That is why the mats are now part of our construction toolbox for upcoming projects.”
The Orkoien wind turbine is also equipped with a new technology to avoid using greenhouse gas called sulphur hexafluoride (SF6) during the operations phase. This gas is used in medium-voltage switchgear at the base of wind turbines as a insulating agent in the circuit breaker to interrupt electrical currents. While SF6 is harmless to humans and animals, it is harmful to the climate and it may only be used under strict conditions, RWE explained.
For the Orkoien turbine, the company tested a SF6-free switchgear, using a mixture of dry air and C5 fluoroketones as an insulating agent. It is just as reliable as SF6, but it is also environmentally friendly.
Notably, this change on RWE’s part aligns with the upcoming EU ban on SF6 for new plants from 2031, the German group added.
