Growing concern about greenhouse gas (GHG) emissions and climate change are profoundly altering the way utilities, businesses and governments plan for the future. Beside direct policy and stimulation, one of the mechanisms to enable change towards a lower climate impact is by trading carbon credits in a capped emissions trading scheme. Because of a (planned) shortage of credits, the credits become scarce in an economic sense, and a price for the credits is created. In this way, the idea is that the emission reductions will be made there where the cost is lowest.
Besides cap and trade mechanism described above, other trading schemes like CDM and JI are directly linked to the Kyoto cap and trade scheme. Also voluntary and other mechanism are being used, that are linked to Kyoto emission markets. Because of limitation in the linking and the large risks involved in these markets, the credits are exchanged at a lower price compared to cap and trade credit markets.

Recent prices for EUA and CER (CDM) futures, from: www.co2prices.eu

Prices for Over The Counter settlement for EUA and CER (CDM) credits, from: ECX monthly report, www.ecx.eu
Wikipedia on Emissions trading
Link to EU resources on Emissions Trading
European Emission Trading System (EU ETS)
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