The deal for the renewable energy and "some" of the large-scale generation certificates is subject to regulatory approval and a final investment decision, Windlab said.
The Kennedy Energy Park is being developed in a joint venture between developers Windlab and Eurus Energy.
It will comprise of 43.5MW of wind capacity, 15MW of solar and a 2MW lithium-ion battery system when complete.
Windlab announced plans for a 58MW hybrid project in October 2015, the first phase of a wider project, the Big Kennedy Energy project.
With the power deal in place, and the A$50 million (US$40 million) raised in an initial public offering last month, the project is moving closer to a final investment decision, Windlab's executive chairman Roger Price said.
As part of the deal, CS Energy has also secured first rights to negotiate a power take-off agreement on the second phase of the project.