Members voted 4-0, with new Commissioner Nancy Argenziano not taking part. The utility regulatory board was charged with deciding whether there was a need for more power and whether it would be economically feasible for its customers.
The decision follows public hearings in April that drew protests from environmental groups. Among the 31 witnesses at those hearings were three Glades County Commissioners who said the plant is desperately needed to create jobs and economic growth.
Opponents argued the plant would contribute to global warming and pollute the famous River of Grass at a time when the state and federal government are spending more than $10 billion to clean it up.