Drivers in St Peter Port may face travel disruption as a number of roads are closed to allow for work to be complete.
Brock Road and the Rouge Huis Avenue junction are closed from today (22 April) until mid-May as part of phase one of the upgrade.
High voltage cables are being replaced, in addition to the installation of a new pillar, to increase overall capacity available in the area.
Doyle Road remains open with access from Beau Sejour.
The second phase is expected to take around five months to complete as it involves extensive and complex excavation work, cable replacement and component fixtures. Guernsey Electricity say the cables date back to the early 1960s.
Access to Doyle Motors during this time will be via Brock Road only while Doyle Road is closed.
Head of Distribution at Guernsey Electricity, Mike Lloyd, says they have worked closely with businesses and residents in the area to minimise disruption.
"These upgrades are essential to help us provide a reliable and uninterrupted electricity supply and by undertaking a larger volume of work in the local area now, we aim to minimise future road closures and disruptions.
“We appreciate that this is an important thoroughfare into Town and our teams will work hard to ensure the project is completed in a timely manner. We will also provide regular updates for the duration of the works.”
Bus routes 31 and 32 will be affected while the work is ongoing.
Prince Albert Road and Mount Durand are also closed so works to link La Charroterie to the new substation a the Princess Elizabeth Hospital can be completed.
Temporary traffic lights have been installed along Queens Road and Mount Row until 30 April.
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