A Queensland electricity company has again beaten the Northern Territory Government-owned Power and Water Corporation in a major tender to supply power to a government building.

The latest Northern Territory Government gazette shows Brisbane firm Q-Energy has been awarded a $795,000 contract to supply power to the Chan Building in Darwin for three years.

The building is owned by the Territory Government.

A spokeswoman for the Chief Minister says it was a commercially awarded contract that has gone through the proper tender process.

Last year, Q-Energy beat Power and Water in a $2.3 million bid to supply electricity to Parliament House.

The Government recently announced Power and Water was increasing its electricity prices by 30 per cent because of its large debts.