The Japanese aren't talking cost however. They don't want to tip their hand.
(I know, I didn't get it either)
Japan ups CO2 offset buying as nuclear power slows
Japan is stepping up efforts to meet its Kyoto Protocol targets by buying more greenhouse gas emissions offsets from abroad than previously planned as its own emissions rise and nuclear power production dwindles.
Japan has become a major emissions credit buyer, using the New Energy and Industrial Technology Development Organisation (NEDO) as its agent. Having already bought 23 million in the past two years, the government says it will buy at least 77 million more tonnes of carbon offset credits by 2012....MORE