China will raise power tariff surcharges for some energy- intensive firms by 50 to 100 percent from June 1, in renewed efforts to curb expansion in energy-guzzling and polluting industries.

For firms that fall into the restricted category, power surcharges will rise to 0.1 yuan per kilowatt hour (kWh) from 0.05 yuan previously, while those under the to-be-eliminated category will see their power price surcharges rise to 0.3 yuan per kWh from 0.2 yuan in the past, the National Development and Reform Commission (NDRC) said in a report posted on its website last week.

These firms are mainly in the aluminium, cement, steel, zinc, ferroalloy, calcium carbide and sodium hydroxide sectors.

Local governments and power suppliers must cancel any ongoing favorable power prices to aluminium, ferroalloy and calcium carbide makers at a designated date, and any preferential power rates in the name of direct trade between power generators and power users but without any approvals must be halted immediately, the report said.

It sourced a joint notice by the NDRC, State Electricity Regulatory Commission and National Energy Administration.

The government had asked local governments and power firms to cease preferential power price treatment to energy intensive sectors in the past, but the calls were loosely followed as local governments wanted to boost their economic output and increase fiscal revenues.

The policies were mostly ignored since late 2008 when the economy was roiled by the global slowdown.