He also said the building's look would be similar to the prior design, given that the planning department laid out a set of requirements for size and shape, he said.
In the report to next week's planning, environment and development committee, council officers have setout some of the problems faced in the past year.
He said it was right that the industry regulator had delayed approval of the types of reactors proposed "to make sure any lessons learned from the events in Japan can be incorporated, enabling us to setout a clear, confident safety case alongside our planning application".
He said the government was "obviously" doing contingency planning - but had to operate on a "plausible set of assumptions", which would be setout by the Office for Budget Responsibility on Tuesday.