Behind the scenes of AD

See what happens at the farm’s AD Plant

Our on-site Anaerobic Digestion (AD) Plant is a complementary part of the farm business, allowing us to turn energy crops and waste potatoes into electricity and a highly potent fertiliser.

There’s a lot going on at the plant throughout the year – here’s a snapshot of how we run this part of Pengelly Farms!

Harvesting

Before anything goes into the Plant, we have to produce it first! Along with our potatoes, we also plant and sow crops of sugar beet, maize and rye which are harvested throughout the year.

Once the crop gets back to the farm, it’s stored in one of our silage pits and the maize and rye is clamped, where it ferments before it is ready to use in the digestor.

Our potatoes also play a key part in our AD Plant – any that aren’t good enough for customers go into the digestor, helping us to significantly reduce food wastage.

Feeding

The AD Plant needs regular feeding, every day of the year, to keep everything running smoothly. We also need to make sure it gets the right amount of each different type of feedstock; if a new type of feed is used, the system has to be acclimatised to it by slowly introducing small quantities.

It takes a lot of feedstock to keep the plant full – about 50 tonnes per day!

Outputs

Along with generating electricity via biogas, which goes straight into the National Grid, our AD Plant also produces two valuable by-products from the process – solid and liquid digestate.

These effectively act as a high-powered fertiliser, and help us to support the growth of new energy crops which will be fed into the digestor in future.

Upkeep

The AD Plant is a large, complicated piece of machinery, with numerous parts that need to be maintained, repaired and replaced over time. Our engineers and Plant team keep a constant eye on things, ensuring that the Plant runs smoothly by responding to alerts in person and remotely, 24 hours a day, 365 days a year!

We also regularly sample feedstock and digestate to have it analysed, and make sure that we putting in and getting out the best possible products.

We’re always on the lookout for more land for growing energy crops for the AD Plant – click to find out more about this farming opportunity in Cornwall.