GUANGZHOU, April 23 (Xinhua) -- Carbon emissions allowances closed at 22.46 yuan (3.34 U.S. dollars) per tonne on Tuesday, down 0.18 percent from Monday, at the China Emissions Exchange (Guangzhou), the largest local carbon market in China.

A total of 381,833 tonnes of allowances were traded on Tuesday, with a turnover of about 8.15 million yuan.

The allowances, officially known as Guangdong Emissions Allowances (GDEA), are carbon dioxide emissions caps assigned to companies. Firms whose emissions surpass their share must buy extra quotas from authorities or purchase unused quotas on the market from those that cause less pollution.

Since its opening in December 2013, the market has traded 111.46 million tonnes of GDEA, with a total turnover of 2.18 billion yuan.

The carbon market in Guangdong covers all companies whose annual carbon dioxide emissions surpass 20,000 tonnes from the province, except those in Shenzhen, which has a separate market. So far, more than 240 enterprises in sectors of power generation, steel, cement, petrochemicals, paper making and aviation have been included.

Activities on the market are reflective of the industry's emissions control cost in Guangdong, a manufacturing powerhouse and big energy consumer in China.