http://www.stuff.co.nz/4513470a10.html
Government officials are looking at cutting the speed limit by 10kmh - and charging motorists to drive in urban centres - as ways of cutting greenhouse gas emissions.
Next month at a stakeholder meeting in Wellington an all-of-government taskforce will present a raft of measures that could become tools in the climate change fight.
The meeting comes after the Government's U-turn this week on plans to introduce its emissions fuel tax next year. That has been delayed till 2011 as a result of concerns about the high cost of living and the record price of petrol.
Lowering the speed limit is just one measure being assessed by the Transport Ministry, as part of a project to provide information to the Government on the expected magnitude and cost of greenhouse gas mitigation.
The initiative is likely to generate controversy - the 100kmh limit has been in place for decades.
"We don't think you need this and we think that would be an over-reaction," AA spokesman Mike Noon said.
"It's an over-reaction against the car, which would be extremely unpopular and certainly not going to be supported and practised by motorists."
A government-commissioned report issued two years ago showed lowering the speed limit by 10kmh would cut aggregate oil demand by 1.4 per cent. It also found a vehicle travelling at 90kmh is 11 per cent more efficient than one travelling at 100kmh.
The taskforce - which includes members from the agriculture and forestry, economic development, transport, conservation and foreign affairs ministries - is also looking at ways of cutting emissions in other sectors, including energy, forestry and agriculture.
The speed limit has been unaltered since the oil crisis in the late 1970s, when it was lowered to 80kmh to reduce petrol use. That was done along with "carless days" in which vehicle owners were barred from using their cars one day a week.
Other measures being looked at by the taskforce to cut emissions in the transport sector include an urban road pricing programme that could involve both tolling and congestion charging, economy labelling of fuel and driver education.
well, I'm not completely against it, but I would also think that it would depend on the vehicle/gearing etc as to what fuel savings you would get.
For instance in my Altezza, I would probably have to drive in 5th gear instead of 6th, as it labours at 90 in 6th. So I guess my fuel economy would be worse.
I guess it gives me a good reason to buy that close ratio gearbox
90km/h on the napier taupo road some are just about to change into 3rd 
