* Government adviser raises Chinese proposal to introduce absolute cap from 2016
* U.S. has announced plans to rein in emissions from its power sector
* Climate negotiators heading to Germany for climate talks
By Kathy Chen and Stian Reklev
BEIJING, June 3 (Reuters) - China is considering an absolute cap on its CO2 emissions from 2016, a senior adviser to the government said on Tuesday, a day after Washington announced new targets for its power sector, signalling a potential breakthrough in tough U.N. climate talks.
Progress in global climate negotiations has often been held back by a deep split between rich and poor nations, led by the United States and China, respectively, over who should step up their game to reduce emissions.
But the statement by adviser He Jiankun, coupled with the U.S. announcement, sparked optimism among observers hoping to see the decades-old deadlock broken. The steps come ahead of a global meet on climate change starting on Wednesday in Germany.
Adviser He had suggested at a conference in Beijing that China would put the cap in place by 2016. But he later told Reuters that the idea was his personal view.
"What I said today was my personal view. The opinions expressed at the workshop were only meant for academic studies," he said. "What I said does not represent the Chinese government or any organisation."
Earlier, He had told the conference: "The government will use two ways to control CO2 emissions in the next five-year plan, by intensity and an absolute cap."
China is the world's biggest emitter. Carbon emissions in the coal-reliant economy are likely to continue to grow until 2030, but setting an absolute cap instead of pegging them to the level of economic growth would mean they would be more tightly regulated and not spiral out of control.
"The Chinese announcement marks potentially the most important turning point in the global scene on climate change for a decade," said Michael Grubb, a professor of international energy and climate policy at University College London.
It is not clear at what level the cap would be set, and a final number is unlikely to be released until China has worked out more details of the five-year plan, possibly sometime next year.
The United States, the world's second-biggest emitter, announced plans on Monday for the first time to rein in carbon emissions from its power sector, a move the Obama administration hopes can inject ambition into the slow-moving international climate negotiations.
"The China-US one is a key trust relationship (in climate talks) and if they are rising above that it sends a very powerful signal to the rest of the world to get serious," said John Connor, CEO of Melbourne-based The Climate Institute.
CHINESE RELUCTANCE ON TARGETS
China is often accused by rich countries of holding back progress in U.N. talks on emissions due to its reluctance to take on a binding target. It is stepping up efforts to clean up or shut down carbon-emitting sources - coal-fired power plants, factories and vehicles - because of a pollution crisis that shortens thousands of lives every year.
The Beijing government has placed air pollution among its top issues on the national agenda in response to public anger and the protests it has sparked.
Focus will now turn to Bonn in Germany, where negotiators from over 190 nations meet from Wednesday for the latest 10-day round of talks in a process meant to lead to a new global climate treaty in Paris in December 2015.
"Interesting hint from Beijing, although the key point will be where (the cap) is set. If ambitious and announced well in advance of Paris, it could be a game changer," said a spokesman for EU Climate Action Commissioner Connie Hedegaard.
Despite the notion of an absolute cap on CO2, adviser He said China's greenhouse gas emissions would only peak in 2030, at around 11 billion tonnes of CO2-equivalent. Its emissions currently stand at around 7-9.5 billion tonnes.
But He said that would depend on China achieving a real reduction in coal consumption from sometime around 2020 or 2025, and on the nation meeting its target of having 150-200 gigawatts of nuclear power capacity by 2030.
The share of non-fossil fuels in China's energy mix would reach 20 to 25 percent in 2030, He added.
(Additional reporting by Michael Szabo in LONDON; Editing by Joseph Radford, Muralikumar Anantharaman, Ron Popeski and David Evans)