GREEN FUEL: Leigh Ramsey and Celia Wade-Brown at Weltec workshop.

FOUR Wellington buses are trialling an alternative fuel that promises to eliminate the black smoke that belches from most diesels.

They are part of the first commercial trial of a new “green diesel” that has been developed by staff at Weltec polytech and Hutt Valley alternative fuels company Veranis.

The new fuel – an emulsified diesel/water blend – is the work of former BMW master technician Tony Devos, business development manager Leigh Ramsey and ex-oil company people.

The group has brought together an unlikely amalgamation of sustainability and fossil fuel to reduce the dirty emissions from diesel vehicles like buses and trucks.

“We’re all close to retirement and ended up back here with an idea we think is worthwhile,” says Tony.

The idea was spurred by the aim of producing a clean fuel from a rapidly diminishing oil supply.

Leigh says the engineers have developed a secret “recipe” called agent X, which allows water and diesel to bond. This is known as an emulsion.

“The water is in such very small droplets,” he says. “[It is] encased by diesel and becomes an emulsion, much like mayonnaise.

“So the engine doesn’t see the water, as it is surrounded in oil droplets.”

Wellington city councillor Celia Wade-Brown says she was “very impressed” with what she saw and strongly supports the Green diesel as a tool to reduce emissions and deal with waste engine oil safely.

“This is a way of improving the liveability of Wellington’s downtown,” she says.

She saw a Veranis presentation to aregional waste forum,  which consisted of local and regional council representatives.

Leigh says while focusing on waste oil fuels using their technology for off-road machinery  Celia asked:s “Can you do the same with straight-run diesel fuel used   in buses?”

“We say yes and with the support of local and regional authorities we now have a pilot programme to prove the viability of this technology in the field.”

He says with New Zealand about to open its doors and showcase itself to the world with the Rugby World Cup next year, a technology like theirs would benefit the country’s 100% pure brand.

DIESEL DATA: Leigh (left) and Tony check emissions output.

What’s behind the new fuel

Tony explains:

FOSSIL fuels are a diminishing resource. Let’s face it, the first time we took a barrel of fuel out of the ground, we had a barrel less.

With no one making new fossil fuel and it’s  not renewable, it must run out. It’s a finite resource.

Humans use fossil fuel at an extraordinary rate and have very become reliant on it (if not addicted to it). So the logical thing to do when running out of a resource is to use it more wisely.

Diesel engines use the chemical energy in 1 kilogram (or litre) of hydrocarbons more efficiently than the equivalent  petrol engine does. Petrol engines are 25% thermally efficient, while diesel engines are 40%.

That isn’t particularly efficient (the petrol engine) and a considerably better argument is to use diesel.

However, diesels have significant downsides: , they produce much more noxious emissions,  particulate matter (PM) and Noxs (oxides of nitrogen).

Everyone will have seen a bus go by and the cloud of black smoke belching out the back – that’s PM

But run a heavy vehicle on ‘green diesel’ developed in New Zealand by Veranis and it almost turns off the soot to a point where you struggle to see it – it doesn’t get created. We burn the fuel more efficiently.

A reduction of 50% in PM is easily achieved.

DIRTY AS: Comparison of green diesel emissions (left) and ordinary diesel.

TONY fires up the engine of an old bus and inserts a sensor, with small blotting paper, in the exhaust.

With the engine revving at about a three-quarter load, a set volume of gas is sucked out of the exhaust system, and runs through the filter. It comes out looking jet black.

Then the fuel is changed to ‘green diesel and the particulate matter left behind doing the same test is massively reduced.

Tony says:

Particulate matter is  very small carbon pollutants that go deep into your lungs and gets stuck and  cause deep lung diseases.

Old and young people are particularly susceptible – the young breath much faster than adults. The old usually have a reduced immune system, which puts them at risk.

A bus in New Zealand has to conform to emission standards. When new, it is at the peak of technology and runs to that standard.

Over the years, it gets moved from the city to suburbs then to school runs, with those fresh new lungs on it breathing the noxious fumes.

They may do the school run for up to 15 years, and then they’re sold to some hippie to end its life.

Euro standard 3/4/5 is a standard for emission measurement and is what new vehicles must meet.

But these standards are constantly being updated and so requiring buses to have cleaner engines actually means replacing the entire vehicle.

So the choice is to replace the bus or put ‘green diesel’ in it. Even the old dunger buses have the ability to dramatically improve their standard of compliance.

Leigh says:

The old dungers are ideal candidates to trial ‘green diesel’.

One of these old buses creates as much noxious emission as around 15 euro 5 buses, so let’s attack the largest polluting part of the fleet.

It also makes good sense to protect the health of the young, who are most at risk.

Veranis also can incorporate waste lubricating oil in its fuel.

Waste oil is a horrific problem in New Zealand. It has additives in it which allow it to mix with water easily.

Most waste oil in  New Zealand  is transported t through Wellington (by either land or sea) before it goes to furnaces in Westport to be burnt as a cheap fuel.

This is extremely risky.

The problem with waste oil isn’t burning it, it is the bulking up of it into large parcels and moving/shipping those parcels geographically far away from where it’s created to dispose of it.

For example,  if a truck was to roll over  in the Hutt Valley anywhere north of Taita or on the Rimutakas , there is the potential to render the Petone aquifer useless for years, if not decades.

Four litres of waste oil make a million litres of water undrinkable.

Oil industry experts involved in Veranis say in comparison to diesel and petrol, waste oil is one of the hardest of hydrocarbon products to clean up.

Veranis would like to see to the bulking-up and transporting of waste oil reduced and see it consumed locally close to where it is created by  re-circulating it back into the diesel fuel-stream using ‘green diesel’ technology.

This eliminates the risk of the current model and turns what is considered a waste product into an asset for recycling.

Bus depots are very good trialling places. They have central fuelling stations in their own yards, creating their own waste oil on site, doing the same circuit every day.

In terms of data, it is a great control.

We can put data logging and emission sampling equipment on a bus to measure what it does out on the road, come and download the data collected into the laboratory computers

Then we can recreate those road conditions on a state-of-the-art dynamometer, which allows him to make repeatable tests.