Vertical farming—the process of cultivating produce in stacked, indoor shelves, rather than side-by-side in fields—is a fast-growing industry (pardon the pun). Since it was conjured (or revived, depending who you ask) in a 1999 Columbia University lecture, the technology has grown into a global industry set to be worth $13.5 billion by 2030.
Companies like Plenty, Bowery Farms and Infarm have innovated vertical farming with a dazzling array of modular, IoT-connected smart devices, which can improve plant “recipes” (the insider term for creating better, more nutritious food) and ramp efficiency alongside vast improvements on water and land usage.
Berlin’s Infarm, for example, claims to have saved over 10m gallons of water and 500,000 square feet of land across its 1,200 farming units, installed in supermarkets in restaurants).
But it is scale and efficiency that proves vertical farming’s bete noir. Leafy greens—low on energy demands and relatively high in price—constitute the lion’s share of output. High-energy food like cereals and potatoes, essential to human survival, remain firmly within the wheelhouse of traditional farms, which already occupy 40% of livable land on Earth, and one of our biggest environmental threats.
“What’s really needed, and that will come with time, is a humanitarian aspect to (vertical farming), which addresses food crises and starvation issues in, say, sub-Saharan Africa where farmers have to put up with horrible things like invasion of locusts,” says Dickson Despommier, the professor who popularized the medium 22 years ago. “Locusts would have a very difficult time invading a vertical farm.”
To feed the world, however, vertical farms need better lights. LED technology has already skyrocketed since its mainstream rollout in the 1960s. “Haitz’s Law” dictates that LED light increases by a factor of 20 and cost drops by a factor of ten every decade.
“The direction is clear: the prices have gone down, the efficiencies have gone up, and I see that continuing,” says Lars Aikala, CEO of Valoya, a leading supplier of LED lights to the vertical farming industry.
But things are getting more complex. Nowadays companies like Valoya can tinker with light spectra to increase growth rates in certain plants while reducing energy costs. “When we started in 2009 this field was pretty much untouched,” says Aikala.
Experts expect Haitz’s Law to tail off in the coming years, as technology becomes smaller, compacter and tougher to scale up. Rather, the next big leaps in LED technology will come via smart sensors, which will help lights replicate night and day, isolate spectra and better tailor themselves to plants’ preferred sunlight.
“If growers want to replicate seasons all year round they have to replicate and control all these parameters in a very narrow window, so plants can survive and grow in a healthy state all year round,” says Fei Jia, technical solutions manager at Heliospectra. “LED lighting allows this because of a high photon efficiency.
“Smart farming is the trend in lighting.”
An added bonus is that around 95% of an LED light is recyclable, helping vertical farmers persuade the public they’re not just a flash in the pan. When sensor technology can lower costs enough to produce carbs and other vital produce, their companies can finally claim to be solving a part of a food crisis that is leaving almost a billion people without adequate access to nutrition each year.
“We’re just at the starting point of (LED) technology, so price will go down but conversion is going to go up to create more power with less energy,” says Infarm co-founder Erez Galonska. “Now we’re standing on 50-60%, and with the next generation of technology we easily improve the LEDs. It’s already improved so we’re more energy-efficient already.”