Companies must either keep to that limit, buy permits from others below their EU cap, or fund emissions cuts in developing countries, earning offsets called CERs under a U.N.-run Kyoto Protocol scheme called the Clean Development Mechanism.
Until now there was no software link between the EU and U.N. schemes allowing CER delivery, a link originally expected nearly 18 months ago. The delay has made EU carbon market participants nervous as the first significant CER contract settlement date nears on December 1.
The connection should happen shortly, said European Commission environment spokeswoman Barbara Helfferich, who declined to give a more precise indication of the date.
"We are negotiating with the U.N. (climate agency) to decide on the date," she said. "We had a successful test run. Now we have to see that the U.N. is also ready, so setting the date is under negotiation.... It should be shortly."
"I welcome the successful outcome of the testing phase," said EU Environment Commissioner Stavros Dimas.
"This now paves the way for the transfer of credits from the Clean Development Mechanism into the EU registry system."
If the link is not up and running by December 1 then most CER contracts have a clause allowing settlement to roll over until the patch is complete. However, confidence would be harmed at a time many countries are considering introducing their own cap and trade schemes.
"What you really can't put a number on is the impact on sentiment," said a carbon trader who declined to be named.