* FTSEurofirst 300 index up 0.05 percent
* German energy companies fall sharply
* Autos gain after strong car sales data
By Atul Prakash and Danilo Masoni
LONDON/MILAN, Sept 15 (Reuters) - European shares were little changed at midday on Tuesday, with German energy companies RWE and E.ON down after a report said they needed to set aside more money to shut down nuclear power plants.
Investors were reluctant to make big bets before the Federal Reserve decides on Thursday whether to raise U.S. interest rates for the first time since 2006.
Shares in RWE and E.ON both fell more than 7 percent after Spiegel Online said they were short as much as 30 billion euros ($34 billion) of the money they need to set aside to build a safe disposal site for nuclear waste, as part of Germany's exit from nuclear power. E.ON, however, said that nuclear provisions were adequate.
"Uncertainty about the Fed's likely decision continues. If there is no rate hike on Thursday, it could also give a signal that the Fed has some concerns about the health of the economy," said Christian Stocker, strategist at UniCredit in Munich.
The mood among investors in Germany, Europe's biggest economy, slumped in September to its lowest level in 10 months, hit by fears about slower exports to emerging markets, a survey by the ZEW think tank showed on Tuesday.
The STOXX Europe 600 Basic Resources index fell more than 1 percent, the top sectoral decliner in Europe.
"Chinese demand for industrial metals continues to be weak and there are some overcapacities in the mining sector. This is a combination which is negative for the sector," Stocker said.
Miner and commodity trader Glencore also fell, as a slowdown in demand sent coal prices below levels last seen in the global financial crisis of 2008-2009.
The auto sector instead rose 1 percent after figures showed European car registrations surged 11.5 percent last month as a regional market recovery gathered pace.
At 1200 GMT, the pan-European FTSEurofirst 300 index was up 0.05 percent at 1,397.80 points. The index ended 0.5 percent lower in the previous session.
Although the benchmark index is up more than 5 percent from a low it hit late last month, it is down about 14 percent from its peak two months ago, mainly on concerns about the pace of economic growth in China and the prospects of a U.S. rate hike.
Europe bourses in 2015: link.reuters.com/pap87v
Asset performance in 2015: link.reuters.com/gap87v
Today's European research round-up
Editing by Mark Trevelyan, editing by Larry King