There are blobby chocolate buttons. Chocolate hazelnuts. Orange creams. Walnut whips whose whirls have gone a little bit wonky.

Chocs away

Chocs away: Andy Pag and his co-driver John Grimshaw are setting out on a 4,000-mile drive across the Sahara in powered by fuel which began life as chocolate.

Not to mention disintegrating flakes, chipped chocolate caramels and enough squished family-sized bars to send Augustus Gloop, the greediest child in Charlie And The Chocolate Factory, into an all-day feeding frenzy.

Alas – as far as chocoholics are concerned – the confectionery arriving by the truckload at the Ecotec plant in Preston is not for eating.

These are the misshapen, the melted and the rejected, and they will all be transformed into a more precious commodity: fuel. Or, to be more precise, bio-diesel.

The idea of pulling into a filling station and asking for a tank of white, milk or plain might seem preposterous.

But later this month, Londoner Andy Pag and his co-driver John Grimshaw, an electrician from Dorset, will set out on a 4,000-mile drive across the Sahara in a Ford Iveco Cargo lorry powered by just that: fuel that began life as chocolate.

From the south coast of England, they will take the ferry to France, drive through Spain, the length of Morocco, turn left in Mauritania and plough on through the desert until they reach the desolate city of Timbuktu in Mali.

This isn’t just a wacky adventure.

The pair want to highlight the benefits of bio-diesel, which is better for the environment because it produces lower carbon emissions than fossil fuels and is made from renewable resources.

"Timbuktu is renowned for being the back of beyond," explains Pag, who is 34.

"If we can make it all the way there on bio-diesel made from chocolate, then there’s no reason why people at home can’t run their car to the supermarket on the same thing.

"It’s also a city on the sharp edge of climate change. It used to be a river port town, but now the river is 20km away and the edges of the town are in danger of being swallowed up by sand-dunes."

The trip came about because Pag – who has always loved exploring and has already made several expeditions across Africa – realised: "There’s a certain hypocrisy in enjoying beautiful landscapes by driving a great big, dirty diesel engine through them."

He then considered making such a trip in a carbon-neutral way.

PAG approached Ecotec, a firm in north-west England which makes fuel from renewable resources.

By coincidence, they had just been talking to one of their customers, a large chocolate manufacturer, about the possibility of recycling chocolate seconds – otherwise destined for animal feed or landfill sites – into green fuel.

Thus, the Biotruck Drive to Timbuktu was born. Pag, an engineer-turned-investigative journalist (who also runs a wedding website), expects the trip, along bumpy, pot-holed roads and through dusty deserts, to take four weeks.

"We’ll be sleeping in tents and eating local food, so I’m looking forward to some good goat kebabs," he says.

A veteran of adventures, he thinks the voyage will be easier than one he made with his wife from Diassi in Senegal to Angola.

"It took us a week to drive 200km because the road was so treacherous – it was like driving through a swamp," he recalls.

"We had to repair bridges before we could cross them, and sometimes cut our way through the trees.

"By contrast, this trip should be straightforward. I’m looking forward to the area around Timbuktu.

"The river Niger is an inland delta, so amid the desert scenery you have pockets of cultivated green and mud brick architecture – the buildings look like they will dissolve in the rain."

Pag and Grimshaw will be travelling in recycled vehicles – they have been salvaged from scrapyards.

The first part of the journey will be made in a two-wheel-drive truck that used to belong to an auctioneers in Preston, had been abandoned for two years and was about to be turned into scrap.

This is large enough to carry all the fuel, plus the two Landcruisers for the final 130 miles when, in the approach to Timbuktu, the Tarmac road runs out, making four-wheel-drives necessary.

One of the Landcruisers was bought on eBay and had been in the scrapyard; the other has a slightly sketchy history.

"The guy I bought it from said it had been used in a bank job.

"Apparently, the police damaged it when they were moving it out of the front of the bank.

"As it was effectively a writeoff, we got it practically for free."

They will also be taking 1,500 litres of bio-diesel made from 3,000kg of chocolate misshapes, the equivalent of 10,000 packets of milk chocolate buttons or 1,200 family-sized bars of chocolate.

But if Pag and his co-driver run out of provisions they cannot just dip into the petrol tank.

The bio-diesel bears no resemblance to a bar of fruit and nut.

"The exhaust doesn’t smell like chocolate, I’m afraid," says Pag.

"It’s just a golden liquid that looks like normal diesel and has the same consistency – chemically, it’s almost the same, except that it has less carcinogenic polluters."

The process by which it is produced sounds simple.

A spokesman for Ecotec, which made it, says: "You could almost do it in a pan on your kitchen stove."

First, the cocoa butter is extracted from the waste chocolate via a secret mechanical process.

The sugar that’s left over is used to make bio-ethanol, which isn’t used in the chocolate bio-diesel but can be used as a petrol substitute.

The cocoa butter is then melted, before being mixed with methanol and caustic soda – chemicals which you use to unblock your sink. These remove the fatty acids from the mixture.

Finally, the liquid is "washed" – a technical term that means acid is added to neutralise its pH level.

ECOTEC say they have "4,000 tonnes of waste chocolate available".

But if the project takes off, they could easily obtain more.

"We can use anything that comes off the production line," the spokesman says.

"It’s good for everybody. It’s good for the environment because it keeps the chocolate out of landfill sites, and it’s good for the company we get it from because we pay them for it."

The fuel is sold mostly to commercial users, but anyone with a diesel vehicle can pay 91p a litre to fill up at Ecotec’s licensed pump – the only one in the world that sells chocolate diesel.

When Pag and Grimshaw travel to North Africa, they will be taking more fuel with them than they expect to use.

"Our lorry does about 15km to the litre," says Pag (that’s 15km to eight family-sized chocolate bars).

Yet because the fuel does still produce some carbon emissions, the trip won’t be carbon neutral unless some of its output is off-set.

To do this, the pair are taking a small processing unit that can convert waste oil products into fuel and which they will donate to the Mali people when they arrive.

"Mali has had famines in the past, so it’s important they don’t use the unit to convert food material," says Pag.

"I’d expect them to use the waste oil from the fish they fry as street food, or the oil from a crop called jatropha that grows almost as a weed."

Will Pag be taking a few KitKats, in case he gets peckish?

"Well, I guess we will put a few bars of something in the glovebox.

"Though they probably won’t last very long before they melt…"