Vertical farming: increasing food security and reducing emissions with our tailor-made tariff

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At Octopus Energy, we’re using technology to develop new ways to power some of the most sustainable, innovative businesses with 100% green energy. One of our tariffs, Vertical Power, is specially designed to power Vertical Farms, but what exactly are these farms, and why are they so important?

Vertical farming is our ticket to solving some of the biggest issues facing food supply and farming today. It allows crops to thrive locally, irrespective of the weather; making better use of our limited space and water, and reducing CO2 emissions caused by transporting food around the world.

So… what actually is vertical farming?

An image of crops grown on stacked shelves

Vertical farming is the process of growing crops indoors in a high-tech controlled environment using LED light. It's called 'Vertical' because the crops are grown on shelves in water (Hydroponics), air (Aeroponics) or soil, on minimal floor space, enabling these warehouse-type buildings to ‘crop’ up anywhere - including urban areas where food demand is highest.

This clever technology increases crop yields by growing crops in their favourite conditions all year round; controlling the temperature, light levels and humidity depending on the growth stage and/or crop type. Lights can be on for 20 hours a day, increasing the growth rates – some crops can grow in just 15 days!

The ability to increase crop yield is becoming more vital as the Food and Agriculture Organisation (FAO) estimates that food production will have to increase by 70% by 2050 to feed the growing population.

Why is vertical farming so critical for a more sustainable future?

Globally, agriculture accounts for nearly 50% of habitable land use, 70% of global water consumption and produces ~23% of global greenhouse gas emissions. It is also the major source of nitrogen and phosphorus loading to water bodies, polluting crucial drinking sources, harming human health and threatening marine ecosystems. With 800 million people undernourished globally, we need a more sustainable food production method to provide for the growing population.

Less exposed to the environmental effects of climate change

An image of two vertical farmers in an underground vertical farm

In a vicious cycle, while farming is driving climate change, climate change is making traditional farming methods more challenging than ever. As the weather is more unpredictable, ranging from heat waves and drought to storms and flash flooding, crop yields are under threat. At the same time, more land is being given to housing as the population increases.

Independent of the surrounding climate, vertical farming is less exposed to these threats and is a more sustainable practice. It demands ~⅕ of the land required by traditional methods, 70-95% less water, 0 pesticides and 95% less fertiliser. If supplied by renewable energy, it has an electricity carbon footprint of zero helping the UK work towards its Net Zero target.

Increasing efficiency is essential to achieving sustainability. The table below shows an example of vertical farming's increased efficiency and reduced resources requirement compared to other farming methods.

Resource efficiency Vertical farming Greenhouse farming Outdoor farming
Water use efficiency 1L/kg lettuce/year 20L/kg lettuce/year 250L/kg lettuce/year
Energy use 250kWh/kg/year 60-180kWh/kg/year 0.3kWh/kg/year
CO2 emissions 158kg/ton of lettuce 352kg/ton of lettuce 540kg/ton of lettuce
Land use efficiency 0.3m2 for 1kg lettuce/day 9m2 for 1kg lettuce/day 93m2 for 1kg lettuce/day
Food miles 43km 800–1600km 3200km
Yield 80-120kg/m2/year 41kg/m2/year 3.9kg/m2/year

Encourages more locally-grown food

Increasing locally produced food with vertical farming will increase the UK's food security and cut our carbon emissions. Currently almost half of our food supply is produced abroad, accounting for millions of tonnes of UK carbon and costing the UK billions of pounds annually.

Cuts food waste

Furthermore, one-third of all food produced globally is lost or wasted, costing the global economy £720 billion a year and the UK £19 billion. Vertical farming addresses this waste by bringing production closer to the consumer, reducing the risk of spoilage during transportation.

What has Octopus Energy got to do with vertical farming?

When it comes to vertical farming, energy accounts for 40-50% of production costs. Zoisa Walton (director of Octopus Energy for Business) and her team have responded to this by creating our Vertical Power tariff which enables farms to shift their energy consumption to the cheapest times of the day/night.

Harvest London is one of the vertical farms we work with to help increase sustainable food production. Located in Leyton, they’re providing fresh, affordable produce not usually grown in the UK such as Thai Basil, direct to local caterers all round London - thus removing hundreds of thousands of food miles a year. They are using 100% renewable energy on Octopus Vertical Power tariff to reduce their energy cost and carbon emissions.

Check out our Youtube video below featuring Zoisa and Chris Davies (CEO of Harvest London)!


Using our Vertical Power tariff, Harvest London creates ‘night time’ for their crops when electricity is in high demand, and most expensive - between 3-7pm. Enabling high electric load businesses to work at odd times is vital when it comes to reducing their environmental impact. This is because it helps them run off the greenest energy, and takes strain off the electrical grid during the busiest times (when the UK has to call on dirty fossil fuel generators to meet demand).

We support the sustainability ambitions and production endeavours of emerging initiatives like vertical farming. Technology and green energy will play a major role in reducing costs and helping to unlock a new era of sustainable farming.

Find out more in our Powering the Future of the Food Industry blog.

Published on 15th January 2021 by:

image of Charlotte Waterman

Charlotte Waterman

Product and Marketing Executive

Hey I'm Constantine, welcome to Octopus Energy!

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