LONDON, Jan 11 (Reuters) - Intercontinental Exchange (ICE) (ICE.N) saw a record number of trades of carbon allowances in 2021, up almost 30% on the previous year, it said on Tuesday. Regions such as Europe and parts of the United States, including California have set up emission trading systems (ETS), putting a price on carbon dioxide emissions as part of their efforts to cut greenhouse gas emissions and meet climate targets. A total of 18.3 billion tons of carbon allowances traded in 2021 on the exchange, up from 14.3 billion in 2020, ICE said. The bulk of these, some 15.2 billion tons, were trades of EU Allowances, traded on Europe’s ETS, which was up from 12.17 billion a year earlier. The price of benchmark EU Allowances soared almost 150% in 2021, pushed higher by moves by the European Commission to reduce the number of permits available. The rapid price rise tempted more financial institutions and trading houses into the market, further boosting demand. read more A record 2.4 billion California Carbon Allowances also traded on the exchange last year up from 1.87 billion in 2020, along with 255 million allowances in Britain’s ETS which launched in May 2021. Some 346 million tons of Regional Greenhouse Gas Initiative (RGGI) allowances also traded on the exchange, up from 231.5 million in 2020. RGGI covers several U.S. states, including Connecticut, Maryland, Massachusetts, New Hampshire, New York, Rhode Island, and Vermont.