* Sees double-digit EBITDA rise, net profit up 5 pct in 2011
* EBITDA up 11 pct in 2010, in line with market forecasts
* To maintain current dividend payout policy to 2013-2014
* Plans to invest 650 million euros in 2011
* Shares up 1.7 percent
(Adds details on dividends, analysts, updates share price)
By Andres Gonzalez and Judy MacInnes
MADRID, Feb 1 (Reuters) - Spanish gas grid operator Enagas reported an 11 percent rise in headline profits on Tuesday, as new facilities brought into operation boosted its regulated revenue, and predicted another double-digit increase in 2011, although net profit growth is set to slow to 5 percent.
Enagas generates most of its revenue from the Spanish state by being paid for the extensions and improvements it makes to the country's gas transportation network.
The company also operates storage facilities and three of Spain's six regasification plants for processing liquefied natural gas (LNG) -- of which Spain is the world's third-biggest importer.
Analysts said the decline in the net profit growth forecast this year was due mainly to an expected rise in the cost of debt as a result of downgrades to Spain's debt ratings over 2010.
UBS analysts said they believed the cost of debt was not sustainable at levels of 2.70 percent in the fourth quarter of last year compared with 2.68 percent in the third.
The utility's net profit rose 12 percent in 2010 to 333.5 million euros ($458 million), in line with forecasts, while earnings before interest, tax, depreciation and amortisation (EBITDA) were up 11 percent at 781 million euros.
Analysts had on average forecast a result of 783 million euros, according to a Reuters poll.
"Enagas managed to surpass its internal targets for 10 percent year-on-year growth in all profit lines," BPI analysts said in a research note.
"This last year of 2010 has already set an optimistic tone on the group's ability to surpass its guidance," they said.
Enagas's shares were up 1.79 percent at 15.68 euros by 1256 GMT, outpacing a 1.09 percent rise in the Madrid market's IBEX index.
The company said it would maintain its existing dividend policy to pay out 60 percent of earnings until 2013 or 2014, but shareholders could see increased returns from that date if annual investments decrease.
The company expects to invest 650 million euros in 2011, in line with its average annual capex target of 700 million, and place assets in service for a similar amount, up from 644 million in 2010.
"If after 2014 our average annual investment over the next five or six years is lower, as I believe it will be, then logically our dividends should increase," Llarden said.
A final dividend for 2010 is expected to be paid in July, but the company said it could not provide any details. In December it paid a gross interim dividend for 2010 of 0.312 euros a share, up 10.1 percent from a year earlier, and last year also paid a final dividend on 2009 results of 0.466 euros. ($1=0.7289 euros) (Additional reporting by Martin Roberts; Editing by Greg Mahlich)