The company says the $22million project will maintain a ``safe and reliable electricity supply'' to west Camden.

Considered ``essential infrastructure'' under state planning guidelines, the project will be assessed and determined by Integral Energy, making it almost certain to go ahead.

Camden High School principal John Jarvis said Integral Energy representatives told parents at a recent meeting the company had also considered building the substation opposite the West Camden Sewerage Treatment Plant.

``I fully understand we have to have more power but I just think they really need to put more thought into how far they are from residents,'' Mr Jarvis said.

``There's no conclusive evidence on whether it's safe.

``If there were other sites available that aren't near a school and homes, why not go with that?

``I can't imagine lots of people wanting to build a house near sewage works.''

Integral Energy's spokesman said the site on Cawdor Road about 250metres from the school, provided ``the best balance of social, environmental, health, economic, technical, operational and safety considerations''.

He said the site opposite the sewage plant wasn't suitable because it posed safety risks.

Cawdor Road resident Kristin Jones said she was concerned about how being in close proximity to the substation would impact on her health and safety.