As many as 35 000 people in the sugar cane industry could lose their jobs if Eskom is granted a 16% electricity increase, the South Africab Cane Growers' Association said on Thursday.

The increase could result in the closure of four mills, the association's financial affairs director Thomas Funke said at a public hearing held by the National Energy Regulator of South Africa (Nersa) in Durban.

He said the sugar cane industry made R10-billion a year and employed 350 000 people.

There would be a 19.4% loss of income in the industry if the increase was granted. It would also have a dramatic effect on food security.

"We believe the increase is not appropriate and not affordable. A double-digit increase will have serious impact on net returns."

Funke said an increase higher than inflation was not possible for the association to digest.

National Union of Metalworkers of SA president Cedric Gcina warned that an electricity increase would negatively affect industries and the poor.

In his submission, he highlighted the impact the increase would have on the smelting industry.

Gcina said that in a snap survey in November, ten energy intensive companies indicated to Numsa that electricity accounted for 37.04% of their operating costs.

The survey revealed that with the proposed electricity price increase, operating costs would increase by on average 6.83% a year, and that as a result, two-thirds of the smelting companies may have to close down. Gcina said one company indicated it would retrench workers.

Congress of South African Trade Unions KwaZulu-Natal secretary Zet Luzipho said Eskom wanted to operate like a private company whose main objective was to make a profit.

"Eskom must operate according to developmental objectives of the country and not like a profit-thirsty monster it has become."

He said the proposed increase would result in hikes of 110%, which would cause high unemployment, poverty and inequality.

Most families in the country were responsible for supporting three to eight members, and most of these families lived below the bread-line on R10 a day, he said.

Luzipho said it could not be correct that people had to brace themselves for poverty every time Eskom wanted to expand.

More than 100 people picketed at the International Convention Centre where the hearing was held.

A group from the South Durban Community Environmental Alliance and members of Numsa sang struggle songs, demanding to be allowed in.

Protesters carried placards reading: "stop Eskom price increase", "poor to pay for Eskom bad planning", and "why is government silent?"

Pensioner Joseph Harker, from Wentworth, said he paid R800 a month for electricity and that the R40 yearly increase to his pension would not cover the proposed hike.