MADRID, Feb. 4 (Reuters) - Shares in Spanish renewable energy firm Acciona fell on Tuesday, hit by draft rules to determine subsidies for wind and solar energy technologies that imply cutbacks for the sector.
The draft rules, sent to affected companies on Monday, set the rate of return for existing renewable energy facilities at 7.4 percent and at 7.5 percent for future operations, versus over 10 percent previously.
"The news is worse than expected, mainly for wind energy," Banco Sabadell said in a note to clients, adding that Acciona was likely to be one of the worst hit.
Acciona shares lost 3.3 percent to 47.485 euros by 0940 GMT, the biggest fall on Spain's blue chip index.
The measures are part of a sweeping government overhaul of the energy sector to curb a 30 billion euro ($41 billion) power tariff deficit, built up after years of policy that kept prices below regulated costs that included green energy subsidies.
The new returns, which vary for over 1,000 different types of technology - including wind, thermosolar, photovoltaic and biomass - and year of installation, imply an overall cut in subsidies to the sector of over 1.5 billion euros.
The new rates are based on a review by two independent auditors and used Spain's 10-year government bond plus 300 basis points as a reference.
Companies have 20 days to give their feedback on the new rules, which have not yet been approved by the Spanish cabinet.
($1 = 0.7397 euros) (Reporting by Tracy Rucinski; Editing by Mark Potter)