Residents of the quake-stricken Christchurch seaside suburb of New Brighton will start having their homes reconnected to electricity tonight.

The area has been without power for over a week following last Tuesday's 6.3 magnitude earthquake.

Lines company Orion said the last of Christchurch's main power substations to be connected - Brighton substation - was confirmed as working yesterday.

About 24,000 houses and businesses in Christchurch still remain without power. Around 16,600 of those awaiting reconnection were in the eastern suburbs of New Brighton and Dallington.

A final test yesterday confirmed a transformer installed next to the Brighton substation was working and people in the area would start to be reconnected tonight, Orion said.

"We caution that it is likely to be only a few hundred at a time."

There were faults on every underground cable leading out of the Brighton substation, which meant the reconnection process was going to be very slow.

"We have over 80 underground cables, each with multiple faults, to unearth and repair, and each fault takes a minimum of 12 hours to locate, dig up and repair."

Orion could not identify which areas would be reconnected first, but said it would be areas on the end of the least damaged cables.

There are 15 generators currently installed in the wider New Brighton area, supplying power to 1800 sites.

As cables are repaired and power supplied through the Brighton substation the generators will be moved to other sites in the area.