Utility spokesman Brent Staeben says the account includes labour and financing costs, and the cost of replacement power while Point Lepreau was out of service.
Staeben says the Crown-owned utility will make equal monthly payments to pay down the deferral account over the expected 27-year lifespan of the reactor.
He says the plan will allow the utility to keep power rate increases at about two per cent a year over the next 10 years, while also paying down its debt by $1 billion.
When the refurbishment began in 2008, it was expected to cost $1.4 billion but NB Power says that ballooned to about $2.4 billion when technical problems and delays extended the project three years longer than expected.
In July, a memo from the Prime Minister's Office suggested the full cost could be as high as $3.3 billion when cost overruns from NB Power and Atomic Energy of Canada Ltd. are taken into account.
NB Power has said the cost of the project to the utility was $2.4 billion.