Approximately 156 million new shares will be issued under the offer, ranking equally with those on issue.
Tilt Renewables' major shareholders, Infratil and Mercury NZ and their relevant subsidiaries, have each provided commitments to fully subscribe for their respective entitlements in the equity raising. They are prevented from participating in shortfall bookbuilds or sub-underwriting.
Infratil currently holds 65 per cent of Tilt shares, while Mercury holds 19.99 per cent.
The 336 megawatt Dundonnell project is Tilt's biggest development yet, comprising 80 Vestas 4.2 MW turbines. They will stand 189 metres high to the blade tip, with a 150-metre diameter rotor and should generate about 1,230 gigawatt-hours of electricity annually. Construction is currently underway.
A total of A$300m for the Dundonnell project costs will be funded by the combination of a syndicated bank debt package from Tilt's existing bankers and a term facility with the Danish Export Credit Agency.
The proceeds of the offer plus cash reserves will be used to fund the remaining expected construction costs, Tilt said.
Citigroup Global Markets and Forsyth Barr are acting as underwriters lead managers of the offer.
Tilt owns and operates eight wind farms in Australia and New Zealand with an installed capacity of 636 MW and an additional 336 MW under construction. It also has a significant pipeline of over 3,000 MW of wind and solar projects in Australia and New Zealand of which just under 1,500 MW have secured the required planning approvals.