The next phase of testing at the new biomass power station near Lockerbie is getting underway.
Residents may hear some noise during the testing
Operators E.ON UK said it involved the release of steam from the plant, which is located at Steven's Croft.
The company warned people living nearby that they might hear some noise which, it said, would not be repeated once the plant had been commissioned.
The main tests are being carried out during morning and evening spells and could go on for a number of weeks.
The £90m facility, the largest of its kind in the United Kingdom, is expected to be fully operational by the end of 2007.