Australia-based Energex has started $10 million-plus work to double the available power capacity for more than 6,500 homes and businesses in Ipswich City's southern suburbs.

The work includes the installation of a second transformer at the Ipswich South substation, as well as upgrades to underground and overhead powerlines in the area.

There are dozens of new houses, units and commercial premises connecting to the local electricity network every week. The company spent more than $40 million in its last financial year on various upgrades.

Once completed, the upgraded substation and improved local supply network will allow Energex technicians to restore power faster after unexpected damage to the network caused by storms, wild weather, vehicles hitting power poles or underground cables being accidentally damaged.

The project is part of a record $4 billion-plus five-year capital expenditure program currently being undertaken by Energex.