The client, WR Bennett, decided that it was the right time to look at reducing the costs of supplying the onsite farm houses with heat. Traditional fossil fuel boilers were installed across the properties and were aging and costly. That’s where a district heating biomass system is the perfect replacement.
Our in-house designers visited the site to assess the requirements and then produced a plan of action which included the installation of two 40ft shipping containers for the plant room and fuel store. The construction of the plant room can be seen above. The containers arrived as two separate units and were welded together on site. They were then ply lined and the fuel store and plant room fitted out.
Once the containers were dropped in position and weatherproofed, it was time to construct the fuel store and plant room. The fuel store was deigned for pellets, however it could be converted to chip at a later date if required. The joiners got to work and, as they say, built the ‘dancefloor’. This is the angled floor which pellets or chip sit on top and are pushed into the auger. Once the floor was complete the partition wall was erected and some lighting installed. Fuel delivery pipes are connected in to allow the pellet deliveries.
Following the completion of the fuel store, we were able to start work on the boiler room. Moving the 2 tonne boiler into place with a telehandler was the first task. It needs to be lined up carefully with the auger to make sure they can be connected and fuel can be transported to the boiler. The three 2200ltr buffer tanks were then moved into place at the side of the boiler. The buffer tanks are dressed and the pipework begins in the plant room connecting boiler to buffer. It is at this time that the back end protection valve is installed which protects the boiler and improves efficiency. The flue, electrics and any heat meters required in the plant room are also installed at this time as the plant room is close to completion.
For this system the client required us to connect to around 8 different properties on the farm. We had already sent a team to site ahead of the plant room construction to install the heat interface units for each property. The HIU is how we integrate the new biomass heat with the existing heating circuit. It allows the tenant to keep the same heating controls and thermostats and also the old heat source as a back up, should the biomass boiler ever fail.
As part of the heat interface units, we installed an Ofgem approved heat meter which allows the client to claim the RHI and also charge the tenant for the heat they have used.
The pre-insulated pipe run was around 100m in total and acts as the veins of the heating system. In a muddy field, the installation team worked extremely hard to wrestle the pipe into place and make the relevant connections in the ground to supply each property. The pre-insulated pipe T’s off the each property and connects to the heat interface units.
By replacing oil and LPG boilers with the new biomass boiler, the system owner is eligible to claim the Renewable Heat Incentive. This government scheme pays the site owner for every kilowatt of energy produced by the boiler. On this installation, it is estimated that the client will gain around a 6 to 8 year payback on investment on the whole system. The RHI lasts for 20 years and the owner can expect a positive cash outcome of around £300k to £400k!
As you can see, we can take a project from start to finish, handle the RHI application and handover a reliable and efficient district heating system for your business.