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* Reverse flows technically possible
* Slovakia has biggest capacity to pump EU gas to Ukraine
* Gazprom has raised legal doubts over reverse flows
* Reverse flows in use in EU for over a decade
By Alexander Winning
LONDON, April 7 Reverse flows of natural gas
from Europe to Ukraine to help it handle Russian price increases
and supply cuts would be possible within hours once the
infrastructure is in place, but the flows could require approval
from Russia's Gazprom first.
Ukraine is in emergency talks with the EU on importing gas
from the West, pumping gas in the opposite direction to the
original design of the pipelines, following a leap in the price
Gazprom charges it for supplies.
Relations between Ukraine and Russia have been in crisis
since popular protests in Kiev ousted pro-Russian president
Viktor Yanukovich in February, after which Russia seized
Ukraine's Crimea region and formally annexed it last month.
Slovakia is the EU's best-placed country to pump gas to
Ukraine should Russia cut supplies, but reversing flows along
any of the four pipelines that take Russian gas to Slovakia via
Ukraine would breach the terms of its contracts with
state-controlled Gazprom, a spokesman for Slovak pipeline
operator Eustream said.
"For a reverse flow, you would have to stop the East-West
flow in one of the (four) pipelines and reverse the flow. But
you would have to have approval from Gazprom," the spokesman
"Gazprom does not agree with this (reverse flows), and thus
it's not an option," he added.
Gazprom Chief Executive Alexei Miller raised questions about
the legality of reversing gas flows to Ukraine in an interview
aired on Russian state television on Saturday.
Gazprom would be able to monitor whether gas is being
re-exported to Ukraine because Slovakia would have to build a
metering station before reverse flows can start.
Officials from Norway and The Netherlands, other large gas
suppliers, have already said they would be unable to supply
Ukraine and other European countries with substantial amounts of
gas in the event of a Russian supply cut.
An industry source earlier told Reuters that the cost of
building the metering station in Slovakia and making some minor
technical adjustments was about 20 million euros ($27 million)
and would take nine months to complete.
Slovakia is looking at the option of pumping around 10
billion cubic metres (bcm) of gas per year to Ukraine, enough to
meet around 18 percent of Ukrainian demand, the Eustream
Eustream said it was working with Ukrainian pipeline
operator Ukrtransgas to try to ensure that reverse flows could
start by the winter, when demand for gas peaks. It has already
built a compressor station to drive gas eastward.
Previous gas crises have disrupted Russian supplies to
Ukraine, a major transit route for Russian gas, and interrupted
onward flows to Europe.
EU member states have been reversing gas flows between
themselves for more than a decade, and the European gas
transmission network is now closely integrated.
Fluxys Belgium, which operates gas transmission
infrastructure and storage facilities, has been able to reverse
gas flows since 1998, when the Interconnector pipeline opened
between Bacton in Britain and Zeebrugge in Belgium.
"Most of our interconnection points, including the
Interconnector Zeebrugge Terminal, can be switched from import
to export and vice-versa," a Fluxys spokesman said.
"It's just a question of a couple of hours before you can
switch from one to the other direction."
Before it was able to reverse flows, Fluxys had to link up
an existing pipeline to a compressor station to change the
pressure of the gas and install a mechanism similar to a valve
that monitors the flow of gas in the reverse direction.
Gas is driven through a pipeline by a pressure gradient,
moving from an area of high pressure to one of low pressure, so
for flows to be reversed, the end of the pipeline with high
pressure and the one with low pressure must be switched.
Before that can take place, flows in the original direction
must be halted for several hours.
($1 = 0.7303 Euros)
(Additional reporting by Martin Santa in Brussels and Michael
Kahn in Prague; Editing by Henning Gloystein and Will Waterman)