Our Crop Nutrients business is developing a state-of-the-art polyhalite mining operation in northeast England, and is currently participating in a large-scale, low-carbon fertiliser field trial run by British grocery retailer, Tesco.
It has been estimated that we need to produce more food in the next 35 years than we have ever produced in human history, given the projected increases in world population1. Feeding these people without harming the planet is a generation-defining challenge of the 21st century; one that could require a 56% increase in food production2and 593 million additional hectares of agricultural land3 – an area twice the size of India.
Innovations such as chemical fertilisers have helped to raise food production by 150% since the 1960s4, while arable land area has only increased by 13%5. Introduced more than a century ago, these nutrient-rich man-made products have played a crucial role in supporting population growth by boosting agricultural productivity. It’s likely that just under half of the world’s population is dependent on synthetic fertilisers6.
However, the global food system – from production and processing to distribution – is responsible for a third of global anthropogenic greenhouse gas (GHG) emissions7, with crop production accounting for 27% of these emissions; 21% of which are attributable directly to human consumption8. We also know that chemical fertiliser use degrades the soil, with fertile soil being lost at rate of 24bn tonnes a year9.
The scale and complexity of the challenge, to increase food production without exacerbating the climate crisis, means that new solutions with the potential to improve agricultural productivity, while protecting the environment and enhancing the soil, must be found.
Polyhalite. A future-enabling natural solution
There are several areas that can be explored to tackle this challenge: from diversifying food production systems to improving land management practices. With 1.3 billion tonnes of food lost or wasted globally – 40-50% of which are root crops, fruits and vegetables10 – improving the sustainability of food consumption is also crucial.
Another important area is the provision of future-enabling products – those that can help the world become cleaner and greener, while sustainably meeting the needs of a growing global population.
One such product is the naturally occurring mineral, polyhalite. Containing significant amounts of sulphur, magnesium, potassium and calcium – four of the six essential macro nutrients required for plant growth – it is ideally suited to use as a fertiliser and can improve food productivity by enhancing the soil, while significantly reducing the environmental impact and improving the performance of chemical fertilisers.
This is where Anglo American can play its part. The world’s largest known deposit of polyhalite is in North Yorkshire, England, at our Woodsmith mine. Since acquiring the project in March 2020, our Crop Nutrients team has been developing a state-of-the-art operation to extract it from underground and transform it into a natural mineral fertiliser, POLY4.
The foundations of a more sustainable solution
POLY4 has several key attributes that are expected to benefit the agricultural sector, with scientific studies proving that it not only increases yield but improves the health of the soil and has enhanced environmental performance compared to conventional fertilisers.
Anglo American has conducted over 1,500 commercial scale, ‘on-farm’ demonstrations to evidence the benefits and value of POLY4. On average, these trials show between a 3-5% improvement in crop yield, the increased productivity estimated to be needed to feed our growing population. But it is the additional, unique benefits that POLY4 brings which differentiate it from conventional chemical fertilisers.
First, there is strong evidence that it increases the crop’s uptake and efficient use of other nutrients, both from within the soil and from applied fertilisers. Greater nutrient use efficiency is a key priority because it reduces the amount of chemical fertiliser required for the same yield.
POLY4’s nutrients have extended availability to match crop needs. A 6% increase in nitrogen and phosphorus uptake has been observed, compared to conventional potassium fertiliser. This is due to POLY4’s multi-nutrient content. This is important because – just like you or I – consuming a more balanced and nutritious diet makes plants stronger, healthier and more productive.
Secondly, POLY4 works in harmony with the soil. It improves soil health by adding calcium, which helps stabilise soil structure; leading to better water infiltration and retention, drainage and aeration. Stronger soils resist compaction and erosion, and provide more favourable environments for soil biology. Plus, unlike chemical fertilisers which require remedial action to counter unwanted impacts, POLY4 has no known detrimental effect – it is low in chloride, pH neutral and does not cause a sudden increase in salt index (like conventional potassium fertilisers) which may impair soil biology.
Thirdly, it reduces environmental impact. It has low waste production due to a 1:1 ore to product ratio, with no chemical processing required between the mineral’s extraction from the orebody and its application to the field. The ore is merely crushed and granulated which, together with the low impact design of the Woodsmith operation, means the POLY4 – from mine to field – will have a total carbon footprint that is up to 85% lower than that associated with the production of comparative conventional fertilisers.
Tried and tested
We continue to explore new opportunities to validate the product’s potential and we are currently participating in a large-scale, low-carbon fertiliser commercial trial with the UK’s largest supermarket chain, Tesco.
The aim of the trial is to identify the most sustainable and cost-effective alternatives to conventional fertiliser options. Held across 1,300 hectares in the 2023 growing season, and using seven different low carbon fertilisers, including POLY4, the plan is to scale this up to a minimum of 4,000 hectares in 2024 across Tesco’s field vegetable suppliers. The first year of the roll-out is expected to produce up to 70,000 tonnes of fresh produce including lettuces, carrots and potatoes, growing to some 200,000 tonnes in 2024.
Tesco expects the trial to reduce the greenhouse gas emissions footprint of producing the vegetables involved by up to 20% across the growing season, compared to using conventional chemical fertilisers. The initiative could help pave the way for large-scale, low-carbon fertiliser production.
Ekaterina Yakovenko, Innovation and New Business Model Manager for Crop Nutrients, said: “We are very proud to be playing our part in the Woodsmith project, which is aligned with Anglo American’s purpose – to re-imagine mining to improve people’s lives – and our aim to become a true materials solutions provider and partner of choice for any agribusiness that prioritises environmental responsibility, and long-term sustainability.
“As well as playing its role in helping to solve challenges in the global agricultural industry and meeting the nutritional needs of the world’s population, the Woodsmith Project, and our efforts to bring our POLY4 fertiliser product to fruition, is expected to have a direct and indirect economic impact, as well as making a difference to local people and businesses.”
A commitment to bring Woodsmith to the world
Currently, two mine shafts over a mile deep are being built, along with a 37km-long tunnel to the granulation plant. A fundamental aspect of Anglo American’s Sustainable Mining Plan, the mine has been designed to ensure limited surface and environmental impact.
In February 2023, Anglo American announced that capital expenditure for Woodsmith this year will be £650 million and approximately £800 million per year for the following three years, as it moves towards reaching polyhalite by 2027 and making a positive difference to the global fertiliser markets.
The project currently employs over 1,650 people at sites in Whitby, Teesside and Scarborough with the majority from the local surrounding communities. A recent study has shown that the project has contributed £222 million to the Yorkshire and Northeast economies last year, and over £1.2billion since it began.
To learn more about Woodsmith and POLY4, click here.
1‘The food security challenge’; Global Food Security (GFS), the UK cross-government programme on food security research; https://bit.ly/3KDkPO8
2‘Sustainably feeding the world in 2050: Are efficiency and equity the answer?’; EIT Food; 20 August 2019; https://bit.ly/3mLoXDq
3'How to sustainably feed 10 billion people by 2050, in 21 charts; J. Ranganathan, R. Waite, T. Searchinger, C. Hanson; World Resources Institute; 5 December 2018; https://bit.ly/3ZFT8KM
4‘Remarks by CFS Chair at the Global Leaders’ Symposium at the Food for Future Summit 2022’; Committee on World Food Security; 24 February 2022; https://bit.ly/3mPohwG
5ibid.
6‘How many people does synthetic fertiliser feed?’; H. Ritchie; Our World in Data; 7 November 2017; https://bit.ly/3FeM2F1
7‘Greenhouse gas emissions from food systems: building the evidence base’; Francesco N Tubiello et al; Environmental Research Letters; Volume 16, Number 6; published 8 June 2021, https://bit.ly/3ZvEJAr
8‘How many people does synthetic fertiliser feed?’; H. Ritchie; Our World in Data; 7 November 2017; https://bit.ly/3FeM2F1
9‘Global Land Outlook – First Edition; Part 1, Chapter 4; Pg. 52; United Nations Convention to Combat Desertification (UNCCD); 2017; https://bit.ly/3yzh1aY
10‘Food Waste Facts’, Stop Wasting Food Movement, https://bit.ly/3Lfo2W9
i https://www.tescoplc.com/news/2023/greener-greens-tesco-launches-uk-s-largest-low-carbon-fertiliser-roll-out-to-increase-food-security-and-cut-the-carbon-footprint-of-its-veg/