Ust Luga's export capacity is 20 million mt/year, according to the terminal's website.
A European utility-trader said coal prices were unlikely to be affected as the temporary reduction in capacity was small compared with overall volumes being shipped from the terminal.
"I have seen [the terminal's] export capacity on paper and the reality of how much coal is shipped through there, and it's so much more," the source said.
The source said physical coal shipments from Ust Luga were close to double the terminal's official capacity.
"I don't think it will have much effect on the price," the source said. "Producers will always talk up supply tightness regardless."
The terminal on Friday said it had shipped 9 million mt of coal so far in 2018, similar to volumes over the same period of 2017.
A European trader also said the maintenance would not have a significant impact on exports out of Ust Luga.
The source said summer works were likely to keep volumes flat compared with 2017, as the higher export volumes expected for this year would be negated by the maintenance.
A steady flux of vessels were fixed in the region at lower levels on the back of the announcement as shipowners with vessels in the region had little choice.
"They have to fix at lower rates if they don't want idling ships in the region," an operator said.
Time-charter rates were around $6,000-$7,000/day for Panamax coal vessels in the Baltic region, from around $10,000/day before the maintenance was announced.
Unlike most major coal producing nations, Russia does not have one key export terminal and instead ships thermal coal from several ports in the Baltic region, most of which are not within its own borders.
The main terminals in the region are St Petersburg, Ust Luga and Murmansk in Russia, Riga and Ventspils in Latvia, as well as ports in Estonia, Lithuania and Finland.
Russian thermal coal comprises roughly 43% of the total EU import market, according to Eurostat data.
An offer was heard Wednesday for 5,850 kcal/kg NAR coal around $90.30/mt FOB Baltic. S&P Global Platts most recent weekly FOB Russia Baltic assessment for 6,000 kcal/kg NAR coal was $85.25/mt on Friday, but sources said this increase in price was largely due to rising prices in the CIF ARA market instead of any supply shortage concerns.
Platts CIF ARA 6,000 kcal/kg NAR price was assessed at $94.60/mt on Wednesday, from $89.35/mt a week ago.
