IT may not be everybody’s idea of fun, but thousands of people consider watching Ana Louise or Rebecca Caron rattling along the motorway to be an enjoyable pastime.

The pair attracting the attention are no ladies, of course; they are two of the iconic Eddie Stobart lorries that are individually christened and have spawned an official fan club.

Eddie Stobart’s green livery is recognisable across the country but the company is getting greener still as it moves in a new eco-friendly direction.

From this week there will be a new name for transport geeks to record in their Stobart logbooks — Eddie the Engine — and you won’t see him stuck in a traffic jam on the M6.

On Tuesday, the Cumbrian company famed for road haulage will launch its first foray into rail freight after investing £5.5m in a service that will shift goods for Tesco. The trains will run between the retailer’s depots in Livingston in Scotland and Daventry in Northamptonshire.

“This was our idea,” said the haulier’s chief executive, William Stobart, whose brother Edward created the business 36 years ago. “It’s greener and you have to think of these things, haven’t you? Tesco had been looking at rail but couldn’t get it to add up. We had to prove that rail could be as reliable as trucks. We did a lot of tests.”

The train will ship a cargo equivalent to the capacity of 26 lorries, before being reloaded and returning to the Midlands — all within a day. It will travel at an average speed of 40mph, which is comparable with a lorry, although the whole process will take slightly longer because of additional loading and unloading.

Still, Eddie Stobart claims that because Tesco will fill the train on both legs of the trip, the supermarket chain will benefit from savings of about 20% on a load that industry figures suggest would cost some £13,000 for a one-way road trip.

That looks like a huge reduction in an industry operating on narrow margins. For the year ending last February, Eddie Stobart is expected to announce profits of £5m on revenues of about £130m. Considering the company runs 850 vehicles, that works out at less than £6,000 profit per lorry per year.

But, strangely, it is the environmental benefit of rail that makes the whole project possible, because without almost £500,000 in “green” grants from the Department for Transport and the Scottish Executive the service would not have been financially viable.

“Our understanding is that if we keep on applying for the grant we will get it renewed if we can show the environmental benefit,” said Andrew Tinkler, the haulier’s chairman. “There is an environmental impact on continually taking 26 trucks up to Scotland five days a week.”

The Rail Freight Group (RFG), an industry lobbying organisation, reckons that moving goods by train saves more than 5.6m lorry journeys in Britain each year. It says the private sector has invested about £1.5 billion in rail freight since privatisation, mainly on new locomotives and wagons but also on new freight terminals.

And since the break-up of the state railway in the late 1990s the amount of freight traffic moving by rail has increased by 60%. In that time, rail’s share of the national freight market has grown from 8.5% to 11.5%.

But that is only half the industry’s story. Lord Berkeley, RFG’s chairman, fears that the rail companies’ profitability could be hit by the rail regulator’s review of the charges they pay Network Rail. Freight transporters fear the five-yearly review, now under way, will bring a rise in the amount they pay to use the national network.

The industry has also suffered from a mixed reputation in Britain, where often the distances covered aren’t great enough to justify the cost. If, for example, a train carrying several loads encounters a problem, none of the loads gets delivered on time. On the roads, some lorries would find a way through.

Stobart believes he has the answer to this problem, although it is hardly a high-tech one. “The train is diesel- powered,” he said, “because otherwise it could run only on electrified tracks. If there is a blockage, this train can turn off like a truck and find an alternative route. If we didn’t have that, it wouldn’t work.”

But others view the switch to rail as more of a publicity stunt. Chris Morgan, a logistics analyst at the research firm Datamonitor, said: “It seems to be food retailers who are beginning to look at this, because of the bad press they receive about how far food travels to get to the shelves. But there’s also a pollution benefit. It’s good PR.”

Still, Eddie Stobart claims to be in talks about further rail deals with other big clients, including Coca-Cola, which may convince doubters that the deal is the real thing.

In the meantime, the move to rail will be great news for those die-hard Stobart fans with their notebooks, who will cheer Eddie the Engine as he puffs his way up and down the Tesco line.