Imagine a farm where driverless electric tractors roam the fields, day and night, before silently connected themselves to solar-powered charging points ready for their next autonomous shift.

According to industry analysts, this may no longer be science fiction, but the technology of the near future.

Many manufacturers are developing new energy supplies and autonomous guidance systems for farm vehicles, including John Deere, whose SESAM battery-powered tractor was awarded a special mention at the Paris International Agribusiness Show in February.

The SESAM (Sustainable Energy Supply for Agricultural Machinery) prototype produces 130kW of continuous power, but so far it is limited to about four hours of operation and requiring some three hours to recharge.

The company is also developing guidance systems allowing a driverless 'robot' tractor to follow the movements of an operator-driven tractor, carrying out a similar or following field operation.

David Fairman, sales director at Norwich-based John Deere dealer Ben Burgess, said: 'Technology never goes backwards.

'In the future you may have two or three machines working in a field, with one governing the others. You might have an operator in the master vehicle, or someone standing on a headland with a remote control watching all three, but I cannot see there not being an operator at all.

'What this then leads us to is possibly reducing the size of units. In some ways we have got to the scope of how big a combine can physically be, but what I think we will see is machinery that will work a bit slower and on smaller widths, but it will work 24 hours a day, seven days a week.

'Somewhere in the world this technology is being worked on and tested, but how far away it is, I don't know.'

Mr Fairman said he had seen two major efficiency revolutions during his 30 years in the machinery industry – the widening of operating widths and the introduction of satellite-guided auto-steering.

'These have been the two big breakthroughs – and the next lot of technology will be equally as big,' he said.

'When you think about it, you are already seeing robotic lawn mowers, and vacuum cleaners in your house which go onto docking stations when the owner is out. That is the technology, and it is scalable, so there is no reason why it couldn't happen on a large field.'

ELECTRIC TRACTORS BY 2020?

A research paper for the National Farmers' Union suggests battery electric and diesel-electric hybrid tractors will be widely available from 2020 onwards.

The report says most of the technological progress seen in electrification of transport so far has been in light electric and plug-in hybrid vehicles such as private cars and delivery vans, with more limited expectations for industrial vehicles carrying large payloads.

However, its says recent announcements from Mercedes-Benz, Tesla Motors and others suggest the prospects for both the range and payloads of heavy electric vehicles may change markedly over the next 5-10 years.

The research also assesses the prospects for robot tractors – taking the principles of GPS-guided precision agriculture to new heights, and enabling one controller to manage several vehicles and operations at once.

In the future, it says such robot tractors could make full use of periods of favourable weather by working day and night, under monitoring and control from the farm office.

The Autonomous Tractor Corporation (ATC) of North Dakota, USA, was one of the first to develop a robotic control system in 2012 for its Spirit lightweight tracked vehicle, says the report. More recently, major manufacturer CNH demonstrated driverless tractors from both its Case IH and New Holland brands in August 2016, while John Deere and Fendt/AGCO have also been developing guidance systems, allowing a driverless tractor to follow or reflect the movements of an operator-driven tractor.

The report says: 'Driverless tractors and drones, perhaps with several operating in one place as a robotic 'swarm', are thought to offer particular opportunities for smaller farms to increase their productivity. Along with other present and future applications such as robot livestock feeders and fruit pickers, these new developments in 'agri-tech' could even help farmers and growers to manage post-Brexit anticipated changes in the availability of seasonal labour.'