New Zealand petrol service station owner Z Energy has sealed a $NZ785 million deal to buy US major Chevron's local chain of Caltex-branded stations in a move that will give the local player almost half the country's transport fuel market. In a deal first revealed by The Australian Financial Review 's Street Talk online on Monday, Z Energy is buying 100 per cent of Chevron New Zealand, in a transaction that will include all its remaining downstream interests.