Despite putting its stakes in two British airports up for sale, Infratil says it is still actively looking to acquire new assets.
Infratil made a loss of $17 million dollars in the six months to the end of September, after a profit of $50 million last year.
This is due to a writedown in the value of Glasgow, Prestwick and Kent airports in Britain.
Pre-tax earnings rose 7% to $295 million, led by a pick up in TrustPower, Infratil Energy Australia and Wellington Airport.
Chief executive Marko Bogoievski says competition in the electricity market means TrustPower has lost about 3000 customers.
Despite this, he said TrustPower is progressing with new windfarms in Australia, while Z Energy battles competitors for sales.
Mr Bogoievski said revenue at Infratil Energy Australia increased about 20% in the half year, as a cooler winter in Melbourne pushed gas sales higher.
Both Wellington Airport and NZ Bus assets showed passenger growth.
While Infratil wants to sell its airport stakes, it will consider buying another airport if a suitable opportunity arises.
Mr Bogoievski says Infratil expects full year earnings between $530 - $560 million.
