On the 18th November members of the AgriFoRwArdS CDT as well as the Department of Engineering, University of Cambridge were invited to attend a site visit to Zero Carbon Farms. Zero Carbon Farms grow fresh microgreens and salad leaves 33 metres below the busy streets of Clapham, London, and are an industry sponsor of Cohort 3 CDT student Pat Wichitwechkarn. They are a cutting edge AgTech company that builds and operates Controlled Environment Farms, providing a future-proof and sustainable solution for growing food produce. They use the latest hydroponic systems and LED technology to grow crops all year-round in a perfect, pesticide-free environment using 100% renewable energy. Thanks to a controlled environment, each tiny leaf tastes as amazing as the last, containing up to 90 times more nutrients than its fully grow counterpart. The greens are unaffected by the weather and seasonal changes, and thanks to the prime location, Zero Carbon Farms reduces the need to import crops and drastically reduce the food miles for retailers and consumers.

The start of the tour was scheduled for 15:00 on the Friday and gave plenty of time to see the facilities and speak with the Zero Carbon Farm team. No area was left unexplored and the start of the tour began with the tray preparation and seed germination stage. Host for the tour was Tommy Vermeir, Growing Manager for Zero Carbon Farms. In attendance were AgriFoRwArdS CDT students Pat Wichitwechkarn, Rachel Trimble, Bethan Moncur, Andrew Simpson and William Rohde. Cohort 3 student Pat Wichitwechkarn said that;

During the visit to zero carbon farms on November 18th, Tommy (the grow manager) guided us through the underground farm in London. The location used to be a bomb-raid shelter but is now filled with shelves illuminated with purple LEDs that house a variety of greens. Tommy showed us through the entire process from seed germination to crop harvest. He also gave us a tour of the irrigation and grow systems that are used in the farm.

The growing of the food is done on felt made out of old carpet. They then keep this on trays and flood with water and nutrients. LEDs are used as a lighting source to ensure ideal growing conditions. Lighting and packaging, to energy and waste, every input is carefully managed to optimise efficient growth and suitability. This has allowed Zero Carbon Farms to achieve B-Corp status, naming Zero Carbon Farms the first UK AgTech to be B Corp certified, and only the second in the world. CDT cohort 3 student, Rachel Trimble commented that;

It is rather magical to have food production in such an urban, manmade space.

The growth stages of the produce is then directly managed by moving the trays across staging areas. LED technology is used to carefully provide the exact amount of energy required at each stage cycle. Air flow and heat is also carefully monitored.

Although the current process is highly manual, one area of focus is how to automate each stage of the growing cycle, but also areas such as tray cleaning, while still ensuring that activities carried out in quality-visible roles like packing are completed by the associate workforce who provide the final quality check. Alongside this, Zero Carbon Farms have worked in collaboration with Alan Turing Institute, building a model to allow some level of predictive control of the temperature in the growing stacks. None of these systems could operate if it were not for the carefully managed and controlled environment within the underground bunkers. This is achieved via a vast network of irrigation and pump controls that allows everything from water to heat to be finely tuned.

Cohort 4 student Andrew Simpson commented on the visit;

What a great privilege to be offered first hand access to this eye-opening farm where 21st Century agri-technology inhabits a 1940’s war-time subterranean bunker under a busy London street.  I was quite surprised that we were given full permission to photograph, film and ask as many questions as we liked about how – and why – a farming business would choose to operate underground, away from sunlight and other natural resources.

The answers to all of these questions were open and frank and made a huge amount of sense.  For example, renewably-generated electricity is provided by a company on a carefully measured basis, effectively converting sunlight into highly calibrated artificial light to optimise and control the growth of these premium plants for the food and cosmetics industries, where consistency is key. It makes sense; you can’t control sunlight but you can control artificial lighting.  The same can be said for water, airborne pollution and pathogens as well as of course temperature; who knew? (Well, I didn’t!)

The exceptional team running this organisation invited us all back to visit which was massively kind considering how much of their time we took.  I would definitely encourage anyone who knows little (like me before my visit) about what will almost certainly become a mainstream growing practice in future as we face down climate and environmental change, to take a visit if the opportunity presents itself.

A huge thank you to Zero Carbon Farms for providing an excellent tour of the facilities and answering questions throughout. Also, a big thank you for Pat for making logistical arrangements throughout the visit. If you would like to know more about Zero Carbon Farms or take the visa yourself then please see their website and get in touch.

Do you want to get involved in the CDT?

If you are interested in learning more about what we do and if you share a passion for agriculture and technology then go to our AgriFoRwArdS CDT website to see more about our research, how you can be involved, and how to apply to be a student in the program.