* Fire on April 15 caused by high-voltage cable
* Angola LNG reiterates Q2 export target
* Upstream issues raise doubt over feed gas supply
By Oleg Vukmanovic and Edward McAllister
LONDON/NEW YORK, May 15 (Reuters) - Angola's hopes ofbecoming this year's only major new liquefied natural gassupplier suffered another setback in April after fire occurredat its plant just hours before production was to begin.
This could further delay the troubled project, which is seenas key to relieving a global shortage of the fuel and could help push global LNG prices back towards record highs.
A small electrical fire broke out when a high voltage cableoverloaded as operations were about to begin, according to aprivate report by energy consultants Poten & Partners, seen byReuters and corroborated by industry sources.
In June 2012, a fire ignited at the site, delaying itsopening, which is now 18 months behind schedule.
"Operators were just hours away from making LNG when theincident occurred," the Poten report said of the April 15 fire,adding the overloaded cable was connected to a helper motorlinked to a compressor.
Helper motors are used to get the plant's turbines andcompressors running during start up. Compressors act likeengines, helping cool natural gas to liquid form so it can beput in special tankers for shipping overseas.
Angola LNG, a venture led by U.S. oil major Chevron,declined to comment on the fire, though a spokesman for theproject said production is expected to begin by the end of June,as previously announced.
"Angola LNG is currently in the process of testing andrestarting the plant in readiness for first LNG," the spokesmansaid. The plant was originally scheduled to begin in late 2011.
Angola's state-run oil and gas company Sonangol, which has a22.8 percent stake in the plant, is planning for first LNG to beshipped at any point between May and November, according to thePoten report.
Sonangol did not respond to repeated calls and emails.
It is so far unclear how serious the damage was and how longit will take to fix, though Poten said in the report repairscould be completed within weeks of the incident.
Poten declined to comment on its own report.
Electrical fires are rare, but do occasionally happen whenequipment is being used for the first time, experts said, andrecovery times can vary depending on what has been affected.
"Assuming there is not any significant cable damage outsidethe immediate area, that could be a relatively quick fix," saidJeffrey Beale, president of LNG engineering specialists CH-IVInternational.
"On the other hand, if they don't have readily availablespare parts for that unit, it could be a long time."
The latest incident follows a fire in mid-summer 2012 aftera gas heater unit was left running while the gas flow had beenturned off, a source briefed by engineers said.
MARKET AWAITS SUPPLY
Some LNG traders said the first cargo could come as early asthis month, although others are more sceptical.
The project aims to produce one or two cargoes beforeshutting down again until August for a full battery of tests,traders briefed by Angola LNG representatives said, putting offcommercial production still further.
"The big thing in the market is this project. It is one ofthe reasons Asian prices have come down a bit because people areexpecting it to start," one LNG market source said.
Asian prices rose to $20 per million British thermal units(mmBtu) this winter, before slipping to about $14 per mmBtucurrently.
Angola LNG was initially meant to supply the United Stateswhen construction began in 2008, but subsequent large increasesin U.S. natural gas output has dented import needs and leftAngola seeking other buyers.
Global supplies are however tight and prices have shot tonear record highs over the past year as demand increases andoutput stagnates.
Angola LNG is seen as a key relief to that shortage.
The Soyo LNG tanker, which was expected to take on one ofAngola's first cargoes for export, entered the facility on April16 but sailed out of the port again on April 17, two days afterthe fire and has since left for Spain.
Other Angola LNG stakeholders include Total, BP and ENI with 13.6 percent each.
BP (BP.)