Scottish prison

Sector: Prisons and high-security sites
Equipment: A900 Rocket Composter and Dehydra Dewaterer

The backstory

The UK prison service has been at the very forefront of source segregation and recycling for much longer than most people would realise. It was recognised by the service early within the cycle of waste creation that the value – or indeed the savings – can be had when it is properly separated, cleaned, and bulked together to minimise transportation in and out of the grounds.

Many sites throughout the nation also benefit from having gardens and cultivation plots – growing vegetables that go straight back into the kitchens.

According to food waste charity WRAP, in the UK, over 1 million tonnes of food is being squandered within the hospitality and food service (HaFS) sector every year – costing the sector circa £3.2 billion – and prisons are included in this category.

A number of prisons across the country have decided to boost their sustainability and implement an on-site solution which cuts out the waste-handling middlemen. This has seen them invest in food waste drying and composting equipment, as a way to reduce the volume of wastage and create a useful resource from any food that ends up in the bin. One institution in
Scotland in particular has an interesting story to tell…

The challenge

It’s no secret that prisons are maximum security sites – with both the people and vehicles entering and leaving the premises being documented and monitored at all times.

But the Scottish-based prison – which houses hundreds of inmates who each eat three meals per day – was generating plenty of food waste, and it needed a method of dealing with it effectively.

Prior to contacting Tidy Planet, the site macerated the organic wastage and flushed it into the sewer – as this minimised the number of collection vehicles entering the site. But over time, the fats, oils, and greases started regularly causing problems with blocked drains – floods in heavy downpours became commonplace headaches.

As a result, the prison decided to take advantage of the most environmentally friendly method available at the time – off-site anaerobic digestion, implementing two truck visits per week to collect the material.

However, in order to further improve security and reduce its carbon footprint, the institution sought a solution that would enable it to fully close the loop.

The solution

When approached by the prison, we recommended a Dehydra Dewaterer and a A900 Rocket Composter, as it would allow the gardening teams to reduce the volume and weight of the waste it produces, and then compost on site.

This allowed the prison to decrease the number of vehicle movements – improving security and saving money on off-site collection fees – as well as implement a programme that also upskilled inmates, and employed a circular food waste growing and composting model.

The site now composts all its food waste, and the resulting compost goes back to the grounds and gardens team to be used in horticultural projects. But it’s not just the security and bottom line that receive a boost, the prison also recognises that the transferable skills inmates learn from in-prison activities – such as composting – can also help them when they’ve been released and are reintegrating themselves into society.