Developing alternative net-zero Nitrogen fertilisers with no losses to groundwater and lower cost of N nutrient reaching the crop

Food production depends on crops grown in fields, glasshouses and gardens and all growers use some form of fertilisers or "plant foods". Fertilisers containing Nitrogen can be manufactured by passing air through a large, continuous electric arc (the high temperature forces the Nitrogen in the air to react with the Oxygen so that the Nitrogen can then be used as a fertiliser) - it takes enormous amounts of electricity which, currently at least, is made by burning fossilised fuels. There is another problem with these manufactured fertilisers such as ammonium nitrate and urea (the mostly widely used in the UK) and that is that they are water soluble and 30 to 50 % are likely to be lost to groundwater. That is a financial loss and a pollution risk.

Many plastics contain Nitrogen, originally sourced from air the same way. Up-cycling these plastics at end-of-life of original use can re-use that Nitrogen without incurring the original energy consumption. Initial investigations have shown that one such source contains 22% Nitrogen and that it is, when incorporated into the soil, released to the crop without loss to groundwater. This is an organic, bio-release by the soil fungi.

Initial field trials have shown that the material must be ground up and then could be pelleted in order to handle it but that the pellet must break down rapidly as soon as it gets into the soil. So, the first step is to investigate pelleting the material and to do so within the context of application to the soil . That application method, for many other reasons including energy use and the increasingly narrow weather windows to planting a crop (because of climate change), will be by direct drilling.

The summary plan, then, is to develop a pellet that will stand handling and passage through a selection of common direct drills, to be applied in a measured quantity in a strip just below seed planting depth, and that the pellet breaks down so as to release the Nitrogen content to support crop growth. That growth will be monitored though to harvest . Alongside will be control plots using a conventional mineral fertiliser such as ammonium nitrate.