A building used to house e-voting machines for the longest term lease awarded is currently the subject of a retention planning permission application.

The building's owner, Martin Duffy, stands to pocket over €540,000 for storing the machines in his shed on a 25-year lease, despite the machines being projected to have a life of 20 years.

The premises in which he houses 280 of the machines constitutes an unauthorised development for which retention planning permission must be attained.

Despite being awarded a lucrative state contract, he did not have the required planning permission for the shed, which is in a remote part of Co Monaghan.

Duffy's aunt, Josephine Duffy, is the returning officer for Co Monaghan, but she has said there was no conflict of interest in awarding the contract.

The length of the contract was 15 years longer than any of the other contracts awarded. Local sources estimate the shed could have been purchased for less than the €21,600 it costs for a single year's rent for the storage.

Duffy's shed has had protracted planning difficulties. In 2009, the council issued enforcement proceedings against him for failing to comply with planning regulations. Then this year, he applied for retention.

The planning file describes the shed as "constructed agricultural machinery shed and new agricultural entrance… to retain the use of the building for the storage of electronic equipment".

A sign serving notice of the application could be seen outside the shed in a remote area four miles from Cootehill in Co Cavan.

Duffy's is the only remaining 25-year lease for storing the machines. Most of the leases have been extinguished and the machines moved to a central storage unit in Gormanstown, Co Meath. Two 10-year leases in Kerry and Meath respectively still remain at an annual cost of over €25,000 each.

A spokesman for the Department of the Environment said an interdepartmental task force appointed to oversee the disposal of the machines has now reported and a tender will soon go out regarding the disposal.

Destroying the machines will incur expenses, but selling them, in the event of locating a buyer, would also be problematic as there is an issue over rights on the software.

The Labour Party's spokes­man on local government Ciaran Lynch said there was no market for the machines. "There may be a market for the hardware but not the software. The only clear thing is that the meter is still running on these machines and the state is still paying out three years after trying to end this. John Gormley has not been able to bring things to a conclusion."

The e-voting experiment is estimated to have cost over €50m.