Sometimes we have new ideas that we think can help us enhance our surroundings, but we’re not always able to put them into practice. I’m going to explain how innovation allowed us implement a good idea that will help protect our environment.
It all started in 2009 when we thought that there had to be a more effective way of managing some of the waste that we produce on a regular basis as a result of our electricity distribution operations.
We have been using the gas SF6 (sulphur hexafluoride) for insulation and extinguishing electric arcs for some years, due to its electrical and thermal characteristics.
The gas is used in high voltage areas and it functions by acting as an insulator to prevent the “lightning” (arc) from jumping between the terminals. If it were possible to use just air instead of this gas, the facilities would have to be much larger in order for the arc to be prevented.
However, there are also two drawbacks to this. On the one hand, when it is released into the atmosphere it helps generate the greenhouse effect and on the other, the final disposal of equipment formerly containing SF6 requires a combustion process at a temperature of over 900 º C to cancel the hazards of the by-products. Moreover, this can’t be done in Spain because there are no authorised facilities where it could be carried out. These difficulties are compounded by the fact that the elimination process should be performed on the entire system, which means that large volumes have to be shipped to other countries. This transportation in turn produces CO2 emissions and it doesn’t include the extraction of the gas in advance, which means that its energy efficiency is very low.
It was precisely with the goal of reducing the impact of these drawbacks that the REGALIZ project was set up (Recycling and Eliminating SF6 Gas Located in Zonal Installations). This R&D initiative was allocated a budget of €1.5 million. The aim was to develop a comprehensive and innovative technology that would on the one hand allow to recover the gas and on the other, to process the decomposition by-products produced in the high voltage switchgear apparatus as a consequence of the interruptions in current. Therefore, processing and recovering the gas could enable it to be reused in other equipment, thereby reducing its effects on the environment.
This project required the collaboration of a partner firm, AFESA Medio Ambiente, a company specialising in waste management, and funding from the Centre for Industrial Technological Development (CDTI), which is seconded by the Ministry of Economy and Competitiveness.
The top priority in the work was to build a pilot plant, which allowed to experiment and validate the results obtained. Based on these results, an initial permit was issued by the Basque Government for disposing of a limited number of systems.
The efficiency of the pilot plant allowed AFESA Medio Ambiente to build the first industrial-scale plant in Spain in Lantarón (Álava) to recover the SF6 gas and neutralise the by-products generated in the equipment. It also recently received the administrative permit required to operate under a normal regime of activity. This facility has allowed AFESA to open a new line of business, which currently provides services to various companies in the electricity sector. There is also the possibility of rolling it out to other countries.
The main benefits of this activity for Iberdrola are:
- Enhanced asset management due to lower costs of disposal of equipment containing SF6 gas.
- Recovery of the SF6 gas contained in equipment that reaches the end of its useful life, thereby reducing the amount of gas.
- Lower emissions of environmentally hazardous gases.
The effort made by those involved in this project allowed to implement a good idea that is already enhancing the environment in which we live.
