* Low natural gas and power prices could shut reactors
* Filtered vents could cost up $15 million to $30 million
* Filtered vents would be in addition to hardened vents
Jan 9 (Reuters) - U.S. Nuclear Regulatory Commission (NRC) staff on Wednesday will brief the commission on its recommendation to require nuclear operators to spend tens of millions of dollars to install filtered vents at more than two dozen reactors.
Energy analysts have said the filtered vents recommendation, which were in response to the staff's review of lessons learned from the 2011 Fukushima nuclear disaster in Japan, was just one of several factors that could increase costs of nuclear power and possibly lead to the shutdown of some older reactors.
Other factors include the low cost of natural gas from record shale production that has pushed power prices to decade lows and reduced electric revenues, the lack of government action to limit greenhouse gas emissions, state efforts to pressure power capacity prices lower and increasingly strict environmental water and other regulations, the analysts said.
At the NRC meeting on Wednesday, the nuclear industry will also present their less-costly proposals to filter contaminants out of the reactor's containment in the event of an accident without the installation of costly external filters.
"This is not a decision making meeting for the NRC. The different parties will present the pros and cons of installing filters. We're basically at the beginning of the process ... and will come away from this meeting with a lot more information," Tom Kauffman, a spokesman at the Nuclear Energy Institute, an industry trade group, told Reuters.
A spokesman at the NRC said the commission had not set a date to decide on the filtered vent issue but hoped to have something later this year.
The NRC staff recommended the nation's 31 boiling water reactors with Mark I and Mark II containment types - similar to those damaged at Fukushima - install filtered vent systems. The 104 reactors in the United States provide about 20 percent of the nation's power.
The NRC said the staff has estimated the filtered vents, which could be as large as the trailer on an 18-wheeler truck, could cost about $15 million. Others however estimated the equipment could cost $30 million or more.
The nuclear industry said it was too soon to put a price on the cost of the filtered vents as the NRC had not yet decided what equipment, if any, will be required and the operators had not submitted their plans to NRC to install hardened vents.
In one of its earlier decisions after reviewing the lessons learned from Fukushima, the NRC in March required the operators of Mark I and II reactors to modify or install hardened vents to more effectively and safely release excessive containment pressure after a serious accident.
Mark I containments already have hardened vents and will likely only need to modify their vents to meet the NRC requirements. But the operators of the nation's eight Mark II reactors will have to install hardened vents as they do not exist in that containment type.
The nuclear industry said it had until the end of February to submit plans to the NRC on how they will meet the hardened vent rules over the next two 18- or 24-month refueling cycles.
"If filtered vents are required, that will change everything because the current plans only include hardened vents - not hardened and filtered vents," NEI's Kauffman said.