Call for residents' help choosing replacement buses

20:19, Mar 17 2014

With the death of Wellington's iconic trolley buses now firmly on the horizon, the city's residents will be called on to help choose their replacements.

The type of vehicle that will take over from the city's ageing diesel and trolley buses is a major topic Greater Wellington Regional Council will seek feedback on when it releases its new public transport plan.

Persisting with the existing fleet of diesel buses alongside new trolley buses is one of the options being considered, as is upgrading to fully electric, hybrid, or more modern diesel buses.

Factors include how reliable, noisy and environmentally friendly each option is.

The council is expected to approve its draft plan tomorrow before seeking feedback on it from April 4.

Transport portfolio leader Paul Swain said he did not have a personal preference.


Even though the technology for fully electric battery buses was still in its infancy, he expected Wellingtonians would support a move towards that option.

Of the 278 buses servicing Wellington, 194 fell below the European emissions standard the council wanted to meet, Mr Swain said.

"This is about lifting the environmental standard of the entire fleet, over time."

Keeping the 60-strong fleet of existing trolley buses would mean spending up to $60 million upgrading the 15 substations that power the network, 13 of which were built in the 1950s.

Maintaining the overhead wires also costs ratepayers up to $6m each year.

Mr Swain said the council could not justify asking taxpayers or ratepayers to stump up that much cash, and asking passengers would see ticket prices skyrocket.

Regional councillors Paul Bruce and Sue Kedgley, who both have ties to the Green Party, have called the move to ditch trolley buses "short-sighted and foolhardy".

They say the proposal should be delayed until electric battery bus technology was up to speed.

Mr Swain said they were entitled to their view, but he would be interested to hear where they thought the money to pay for trolley buses should come from.

Even if it could be found elsewhere, it would not be worth it because trolley buses "can only go where the wires go" and could not overtake other buses, he said.

The existing trolley bus fleet was refreshed between 2007 and 2009 at a cost of $27m, using old chassis and motors.



Modern diesel buses

Diesel buses in line with stricter European engine guidelines that are significantly cleaner-burning than older engines.

Cost: $300,000 to $450,000 per vehicle.

Pros: Cheapest capital cost.

Cons: Highest level of emissions.

Modern trolley buses

Electric buses powered by overhead cables.

Cost: $700,000 per vehicle plus cost of overhead wires.

Pros: No emissions, quiet, efficient at moving up steep gradients, newer ones can cover limited distances without wires.

Cons: Costly to set up, maintain.

Hybrid buses

Typically use electric engine in conjunction with a diesel-based combustion engine, which charges an internal battery pack that drives the motor. Kinetic energy from braking is also converted into electrical energy.

Cost: $600,000 per vehicle.

Pros: 25 per cent less emissions than diesel buses, more fuel efficient, no additional infrastructure required.

Cons: Young technology, long- term reliability unknown.

Electric buses

Powered by an electric battery that drives the motor. Can be either an "Opportunity Bus" which recharges at stopping points en-route or/and "Overnight Bus" that is designed to operate all day without recharge. Both type utilise kinetic energy from braking.

Cost: Between $900,000 and $1.1 million per vehicle plus infrastructure and battery costs

Pros: No emissions, quiet, less maintenance cost than diesel buses, high-efficiency electric motors may provide cost advantages.

Cons: Young technology, long- term reliability unknown, cost of building charging stations, size of some batteries can limit seating capacity.


The Dominion Post