The benefits of on-site composting

For the past few years, National Trust properties across the UK have been using a variety of food waste management and collection processes, enabling robust data to be captured and assessed, and benefits defined. The Trust has established that an on-site closed loop system delivers the optimal solution. For properties such as Chartwell House, near Westerham in Kent, which has land on which to grow much of the fresh produce used in its catering services, on-site composting is now the default solution.

As one of several properties composting their food waste on site, Chartwell House, residence of Sir Winston Churchill from 1924 until his death in 1965, is in fact now home to not just one but three composters, together processing up to 15 tonnes of food waste each year.

The property hosts an average of between 1,200 and 1,500 visitors each day, around three quarters of whom take advantage of the propertys catering facilities, comprising of an award-winning restaurant and a kiosk serving light snacks and refreshments. In addition to the visiting public, the kitchen also caters for a busy schedule of special events and private functions. All of the meals are prepared on site with a substantial portion of the seasonal produce coming directly from the propertys kitchen garden.

Research

As one of the earlier adopters of recycling practices amongst National Trust properties, Chartwell conducted thorough research into the food waste processing options available to it and elected to follow in the footsteps of Lanhydrock and Sizergh Castle by installing Ridan composters with which to convert the waste into compost which could then be used on the propertys grounds.

Unlike many other establishments, at Chartwell the responsibility for managing the composting process lies with the catering, rather than the grounds or estate staff. Kitchen personnel use dedicated food waste collection bins with which to ensure that food waste is kept separate from other waste streams. This not only benefits the composting process by removing the opportunity for contaminants to enter the waste but also prevents dry recyclable materials such as glass, paper, tin and card from being contaminated by food waste, thereby increasing the recycling value of these other waste streams.

Beverley Hunt, catering development manager, affirms: We have quite a large catering team comprising 23 permanent staff, who are supported by a further 15 staff in busier periods, all of whom might at some time interact with the composters. During peak hours we can be extremely busy so it has been crucial to maintaining our efficiency levels that we have been able to integrate the composting solution seamlessly into our operation.

Kitchen staff generally empty the contents of our three or four food waste collection bins once a day into one of the composters on a rotational basis in order that all three units are running pretty much in tandem with one another. The resultant compost material is stored in maturation boxes which our gardeners are able to draw from whenever required. All of the compost is used in the kitchen garden to grow produce which is used in the menu so this is a truly closed-loop system.

Head gardener Giles Palmer has been impressed at the quality of the compost: Contrary to any initial doubt I may have had before the introduction of the composters, I have found the quality of the compost to be outstanding; in fact, by blending it with our garden waste, it seems to accelerate the speed with which the green waste breaks down.

Far from hiding the composters away from the public gaze, Chartwell has instead chosen to outwardly promote them to the visiting public and has produced signage and information boards in the kitchen garden which explain the natural process the waste goes through.

Educating people

Ms Hunt explains: We want to help people better understand the impact we are having on our environment and encourage them to adopt eco-friendly practices themselves. We also place Food for Thought information sheets on our tea trays to help increase public awareness and inspire people to consider how they, too, can reduce their carbon footprint.

The composters have brought multiple benefits on a number of commercial, operational and environmental levels. Chartwell has been able to save money by eradicating its food waste disposal costs and producing its own compost as well as enhancing the propertys green credentials. It has reduced the number of general waste bins and collection vehicles required, in the process decreasing bin lifts from 16 per week to just six; at 6 per bin of waste taken away, this equates to an annual saving of over 3,000. In less than three years after their installation, the composters have more than paid for themselves, whilst the waste area is now much cleaner and smarter and with an absence of bad smells which has resolved past problems with attracting wasps and vermin.

Tamzin Phillips, the National Trusts waste adviser, sums up: Of all the different products the Trust has trialled over the last few years, we have found the Ridan composter to be the most suitable for our requirements, being simple to operate, cheap to run and inexpensive to buy and install; it also delivers an excellent quality compost. The staff at Chartwell, who were initially sceptical, quickly changed their opinions and, together with other properties around the country, have helped demonstrate the positive and broad ranging impact that food waste composting can make at a National Trust property.

Ridan co-founder and manufacturer of the composters used by the National Trust, Dan Welburn, has seen continuous growth in the use of composters by catering establishments: On-site food waste recycling is now a financially viable and completely environmentally friendly solution for most catering outlets including schools, hotels, cafs and restaurants. As long as you have some ground, even a small garden, on which to spread the compost, then on-site composting is a practical, low cost solution that works.