To a recent press fanfare, a company based in Japan said it was to build a fully-automated, super-efficient, vertical farm to grow lettuce in Kyoto. By stacking the lettuce on trays under efficient lighting systems, in a 4.8 ha building, they are projecting 30,000 lettuces per day, 10m per year.

That works out at a mind-boggling 1m tonnes per ha (100,000 x the productivity of a wheat field in the UK). The efficiency goes beyond recycling 98% of the water and LED lighting, but by using robotics (including robots to plant seedlings and harvest the heads), so labour efficiency is huge.

I am enough of a boy to think of the boy’s toys element of a robotic vertical farm as having a “wow factor”. And there is a lot of “wow factor” in modern technological approaches to agriculture and food. This may be autonomous vehicles with image analysis systems that can recognise weeds from other plants and zap them individually (as championed by Simon Blackmore at Harper Adams), to precision agriculture and livestock farming providing inputs at an appropriate amount to each small unit of land or each animal according to circumstances.

Some of my own work is with remote sensing to develop smarter ways of managing landscapes to grow food and deliver ecosystem services and the precision with which imaging can work is gobsmacking. John Deere’s big tractors purportedly have more lines of computer code than the first space shuttle. Technology is not just the “Clarkson factor” of machines and widgets: molecular genetics to improve yields, chemical engineering of new inputs, nano-tech applications and so on. Technology, and some very sexy technology, is part of farming.

A tech utopia?

The Japanese factory indicates that there are new ways of doing things that can be efficient and effective. Does this mean we can see a technological future where the grand challenge of feeding the growing population will be solved in a way that doesn’t impinge on the environment with agriculture occurring in factories? Not quite yet.

On average, a person uses about a football pitch of land to provide their food, fuel and fibre each year. If Londoners ate like globally average citizens, about 6m ha is needed to grow the food required by the population of London. The total area of London is about 170000 ha. A typical vertical farm would be able to stack area and gain about 10x the area, and thus the yield, of a non-vertical setting. Even so, it would take 3-4 x the entire area of London to feed London.

London is already pretty full, so the area of several Londons would need to be found somewhere around London, and, of course, some crops are suited to urban farming – typically those are already grown under glass – high value crops like tomatoes, herbs, peppers, cucumbers.

Iterative improvement

Thanet Earth is a pretty good example – even if not a vertical urban farm – of how efficient our own sector is already. It is difficult to imagine urban farming of cereals or livestock taking off. We are likely therefore to need broad acre farming for some time to come.

Nonetheless, urban and vertical farming is part of the mix. It can help produce fresh and local produce. It can contribute to healthy diets in urban centres – where supplying mega-cities looks like a considerable challenge in many parts of the developing world.

Perhaps most importantly, urban agriculture is a route to reconnect people to agriculture. When you have been involved in growing food – even passively by seeing it grown – you see it as more than a “throw-away” commodity. Given that the EU and North America throw away the equivalent production of sub-Saharan Africa each year, changing the way we value our food is important to deliver a food system that is sustainable and works for all people, everywhere.

Technology surely plays an important part in the future of agriculture, but so does us recognising technology’s limits. It is difficult to imagine 11bn people in 2100 eating as unwisely and unsustainably as we currently do, no matter how technologically optimistic we may be. Valuing the world, its natural systems, and living within them – with the aid of technology – is what we need to do.

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If you are interested in writing a blog on a similar topic for the NCUB, please contact Kelly Stiebel, Project Manager (Food) Kelly.stiebel@ncub.co.uk