Shanghai is raising the price of household gas for the first time since 2008, the local authority said yesterday.

Natural gas prices will likely rise by at least 20 percent to reflect global costs and encourage energy conservation, according to the Shanghai Development and Reform Commission.

No timetable was announced, but a public hearing is to be held on July 18 to solicit opinion on two options which were outlined, both three-tier tariffs.

Households consuming less that 290 cubic meters of natural gas a year will see a rise of 0.52 yuan (8 US cents) to 3.02 yuan for each cubic meter of gas.

The cost between 290 and 500 cubic meters will rise to 3.62 yuan.

Gas used in excess of 500 cubic meters will be priced at 4.53 yuan.

Under an alternative option, the price for the first tier will remain at the current 2.5 yuan per cubic meter with smaller rises to 3.32 and 4.23 yuan in the second and third tiers.

Users of manufactured, or liquified, gas, a minority in the city, will pay 1.31 yuan per cubic meter, a rise of 0.06 yuan, regardless of consumption.

"The price rises are in response to China's energy consumption reform," said commission official Wu Xinhua. "It reflects the higher costs of natural gas nowadays and will secure gas resources of better quality."

The market price of natural gas has increased more than 37 percent since 2008, the commission said, while Shanghai only raised prices once for commercial and industrial users in 2010.

Other cities and regions across the country are also adjusting prices after a March statement from the National Development and Reform Commission calling for changes.

It urged a system of at least three tiers with the first covering 80 percent of households to encourage energy conservation. In regions short of energy, the price differences should be greater, the commission said.

China is pursuing price reforms in water, fuel, power and natural gas to better reflect a scarcity of resources and encourage conservation, after a long period of low prices to keep inflation in check.

PetroChina Co said earlier it was losing money on every cubic meter of natural gas it imported due to high prices in international markets.

Last year, China relied on foreign gas for more than 30 percent of its consumption of natural gas across the country.