I raised this topic recently when The Economist pointed to a new Brookings study which argued that the cost of renewables had been severely underestimated. There was some pushback in the comments thread, and now I see that Green Tech Media, an American green energy industry website, has also debated the study and questioned the ethics of The Economist's reporting. Listen to the podcast debate here.

While I'm on the broad topic of climate change, its worth noting some ripples in China's treatment of this issue. China accounts for about 25% of the world's carbon emissions, so along with the US, China needs to be a leader in cutting emissions. But back in early June China signaled that it was not yet prepared to put a cap on its carbon emissions growth:

Any near-term regulation of China's greenhouse gas emissions would likely allow for future emissions growth, a senior government official said on Monday, discounting any suggestion of imminent carbon cuts by the biggest-emitting nation.

Sun Cuihua, deputy director of the climate change office at the National Development and Reform Commission, said it would be a simplification to suggest China would impose an absolute cap on greenhouse gas emissions from 2016.

No decision had yet been taken on a cap and the timing of such a measure was under discussion, she said. Several options were being considered and China would choose policies in accordance with its conditions and stage of development.

"Our understanding of the word 'cap' is different from developed countries," Sun told a conference.

But at a recent conference in Germany, China's chief climate diplomat Xie Zhenhua said:

China might announce a “peaking year” for its carbon emissions in the first half of 2015 when the country would present its contributions to address global climate change, said China’s chief climate negotiator on Monday.

Go read the NY Times' coverage for further context on that quote. That piece also offers a link to a fascinating argument by former US senators Timothy Wirth and Tom Daschle, making the case that binding global treaty on emissions is a chimera, and that the aim for the 2015 Paris conference instead ought to be to get nations to commit to binding national cuts to emissions:

A new agreement should recognize that a simple one-formula-fits-all framework is not feasible: We don’t know how to allocate emissions among nations, the global economy makes this impossible anyway, and the early differentiation between developed and developing economies is no longer valid. Instead, a new start is needed, based in part on what has been called “pledge and review”: Nations will pledge concrete steps to reduce their carbon emissions and periodically submit their progress to the international community for review.

Rather than strive for an elusive, binding global treaty, the idea is to encourage countries to make strong national commitments in their own economic self-interest and then roll those up in the Paris agreement, which would not take the form of a treaty and thus would not need to be ratified. Countries would be motivated to take these actions in response to competition, both economic and political; international peer pressure; and the aspirations of their own people. The overarching goal is to spur national action to bend the carbon curve downward in a meaningful and measurable fashion, giving greater certainty to the private sector to innovate and invest in low-carbon technologies. This is the world’s best option for accelerating progress and averting catastrophic climate change.

Photo by Flickr user Iamoix.