Red Hall Farming Ltd decided to add an additional biomass boiler to their site near Crewe, following the installation of additional poultry sheds. With previous experience of the benefits of a biomass system (a 950kW Reka boiler installed by the team from Core Biomass in 2011) the decision to heat the new sheds with biomass was a logical one. The existing boiler significantly reduces fuel costs, and improves the quality of production by providing a better environment, all whilst shortening the crop cycle, in turn reducing feed costs. Add on the RHI payments for using renewable heating and return on the capital investment is significant over the lifetime of the boiler.
shortening the crop cycle, in turn reducing feed costs
The new boiler was installed in autumn 2014. The boiler is sized to cover the full heating load, with back up provided at point of use via LPG heaters installed within the sheds. The system incorporates a small 10,000ltr thermal store, which helps to smooth out peaks and troughs in the load, giving the boiler time to match output to the heating system consumption. Once lit, the boiler remains on for the entire crop cycle, working very hard at first and gradually reducing in output as the birds grow larger. At the end of a cycle the boiler is shut down and cleaned ready for the next crop. During the crop cycle, the boiler runs continuously. A central de-ashing system collects ash from the boiler, heat exchanger and cyclone and deposits it in an external skip which can be emptied without the need to stop the combustion process.
The mechanical installation was carried out by Bridge Greenhouses, who designed and installed the heat distribution system consisting of pre-insulated steel district heating pipes and Draper Vent fan coil heat exchangers within the chicken sheds. This configuration allows high flow temperatures and ensures longevity and reliability of the underground pipework distribution.
large grate area and heat exchanger area, heavy duty large diameter auger screws, high chrome water cooled grate
The Justsen boiler was chosen for the project because of its robust and flexible industrial design. The fuel used at the site is difficult to burn, with both a high dust content and a high moisture. The industrial design is evident in the very large grate area and heat exchanger area, heavy duty large diameter auger screws, high chrome water cooled grates and water cooled combustion chamber. The Justsen water cooled grate is unique, as each grate is cooled completely and evenly, unlike most water cooled grate boilers where the moving grate rows are not cooled at all. These features facilitate burning of difficult fuels and trouble free continuous use at high loadings – perfect for heating chicken sheds. The extra capital cost is offset by the ability to burn low cost fuels, which can work out to a cost per kW of heat produced as low as 1.2p/kWh. Longevity of the installation was a key consideration, with the RHI subsidy set to run for a period of 20years.
cost per kW of heat produced as low as 1.2p/kWh
The fuel feeding system consists of a large fuel storage bay, with moving floor fuel extraction area of 10x4m. Fuel is handled on site with a telescopic loader, the wood fuel is simply pushed onto the moving extraction area using the loader and piled up high to allow the boiler to run continuously through the night. This is a low cost and durable solution for sites where a loader and driver are on hand during the days. Fuel delivery is via articulated lorry, which can reverse into the fuel bay and discharge a full load inside.
Telephone: +44 (0)1263 577 301
Hall Farm House, Aldborough
Norwich, Norfolk, NR11 7HU