More than 1,700 homes are currently without power across Tendring and Colchester.
UK Power Networks became aware of an issue with undergroudn electrical equipment around 12.40pm this afternoon and are looking to restore the power by 4pm to 1,310 homes.
There are a further 394 homes said to be affected by an overhead electricity fault line which is also said to be solved by 4pm.
The affected postcodes are said to be CO7 0, CO7 7, CO7 8 and CO7 9 in areas such as Alresford, Elmstead Market and Thorrington.
The latest update sent at 12.48pm by engineer David said: "Our engineers are on their way.
"At this point we think the issue is faulty underground electrical equipment affecting 1310 properties.
"Specialist engineers from our control room are also working to divert power remotely, so it's possible your power could come back on at any point.
"We can't always restore everyone this way.
"That's why we're also sending staff to the area to check our equipment.
"Every fault is different, so our time frames have to be estimated but currently we hope to have power back on between 3 and 4pm.
"We must stress that it may become necessary for this to change, depending on what our engineers find. We'll keep you updated with our progress."
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