I-LOFAR wants windfarm ban within 5km of Birr site
The consortium behind the I-LOFAR radio telescope in Birr Castle is appealing to Offaly County Council not to permit any large wind or solar farm within a five-kilometre radius of its site in a bid to avoid “radio noise or pollution”.
In a submission on the draft Offaly County Development Plan, the consortium is seeking planning regulations to protect this “significant infrastructure,” pointing out that radio astronomy involves the detection of the very weakest signals from very distant radio sources often billions of light years away.
Therefore, due to I-LOFAR's extreme sensitivity, it is “vulnerable to interference (even as a result of low power emissions) from terrestrial sources such as wind turbines, photo-voltaic inverters, and emissions from switching electronics such as are used in LED lighting. Although such systems are not intended to be radio transmitters, they in fact emit radio energy over a broad range of frequencies causing unwanted radio noise or pollution.”
Among the measures that the I-LOFAR consortium has requested is consultation with them in relation to any LED lighting installation plans, any proposed radio transmission systems close to their site, or any developments within a 5km radius which require the use of large power inverters.
Made up of Irish astrophysicists, computer engineers, and data scientists, representing Irish universities and institutes of technologies, the group which runs I-LOFAR also appealed to the council to allow “no further large wind farm/photo voltaic installations” within a 5km radius of Birr Castle.
Outside of this zone, they want limitations put on wind turbine heights within a 10km radius, and consultation in relation to wind farm equipment used as they maintained “turbines from certain manufacturers are better than others” in terms of radio interference.
In addition, field tests to see the effects, if any, on the station of any photo-voltaic installation plans should be carried out, the submission continued.
Justifying the call for the planning regulations to be changed to protect the station, the consortium said in its submission: “The internationally important Irish Low Frequency Array (I-LOFAR) at Birr Castle is particularly sensitive to wind turbines, photo-voltaic converters, LED lighting regulator systems, high frequency switching electronics and conventional radio transmitters in its vicinity" due to the "emission of unwanted signals which can enter either the main beam or the sidelobes of the telescope" and "reflection from the turbines (blades and structures) of unwanted signals (both terrestrial and astronomical) into either sidelobes or the main beam of the telescope."
Separation distances of at least five kilometres are therefore crucial in protecting such a sensitive system from "detrimental interference,” the submission sent in as part of the Offaly County Development Plan process argued.
I-LOFAR has already received €3 million in backing from Science Foundation Ireland, Offaly County Council, private donors and eight partner universities.
I-LOFAR is the Irish addition to the LOFAR network and the 12th international station to be built in Europe. It allows Irish astrophysical research to be integrated into one of the most sophisticated telescopes on the planet.