Race to the finish ... NBN Co has to pass 268,000 premises in five months to meet its target. Photo: Nic Walker
NBN Co will need to dramatically boost the speed at which it rolls out its fibre-optic network if it is to meet connection targets it set only last year.
Figures released on Monday show only 72,400 premises had been passed by the end of December after 18 months of fibre rollout. In order to meet its own targets, NBN Co will need to pass 268,000 premises in the next five months.
The company's target is to pass 341,000 new and existing premises with fibre-optic cable by June this year.
Chief executive Mike Quigley vowed to improve the rollout in the second quarter of the year. He said the slow connection rate was reflective of progress in ''the early stages of the rollout'' and blamed delays on difficulties sorting out contractual agreements it must sign with other companies such as Telstra.
''The rollout is not a linear progression, but a rapid ramp-up. We are targeting to pass more premises in the final quarter of the financial year than we will have passed in the entire project up to the beginning of that quarter,'' he said.
''Additional construction resources will be added over the coming months to help achieve these targets.''
NBN Co counts as ''passed'' premises where cable has been laid in the street but a house is yet to be connected.
According to figures released by NBN Co, the company expects to pass more than 50,000 premises next month. NBN Co predicts a rapid acceleration of the rollout, from close to 100,000 premises in March to about 150,000 in April.
In May, the company hopes to pass more than 200,000 premises, reaching 280,000 in the final month of the financial year.
Opposition communications spokesman Malcolm Turnbull was quick to dismiss NBN Co's definition of ''premises completed or under construction''.
''Construction begins according to the NBN Co without anyone even putting a crowbar into the ground. It begins 'when NBN Co issues contract instructions to its contractors for a Fibre Service Access Module', so essentially at a planning stage,'' he said on his website.
In August The Age reported that the cost of the nation's biggest infrastructure project had blown out by $2.9 billion over the next 10 years with the deadline pushed back by six months.
At the time, Mr Quigley and Communications Minister Stephen Conroy said construction costs would rise 3.9 per cent to $37.4 billion and the deadline for rolling out the high-speed internet connection to Australian homes had been pushed back to June 2021.
Higher labour costs, longer network distances and future upgrades to wireless and satellite broadband equipment have pushed up the cost. Operating expenses - primarily staff costs - have jumped from $3.7 billion to $7.8 billion, while savings have been made in other areas.
with Lucy Battersby and Ben Grubb