Building type Business
Building age 1800-1914
Location Snape
Cost of work 500000
District Suffolk Coastal
Features Solar PV Panels,Combined Heat and Power,Insulation and Glazing

Snape Maltings is situated on the Suffolk Heritage coastline in an area of outstanding natural beauty, next to the River Alde and has undergone major redevelopment that now offers a mix of retail outlets, residential units, art galleries and river trips. The listed status of the complex meant a sensitive approach was essential in the redevelopment process at Snape Maltings as it is a Grade 2 listed site. A remote boiler house using environmentally sound technology to heat the entire site suited the owner’s strong environmental principles.

Heating and hot water to all 66 residential properties and 9,000 sq ft retail areas using a highly efficient biomass heating system supplied and installed by Energy Innovations of Theberton, Suffolk was thought to be the best option.

Sustainability Features

System Summary:

  • Boiler: Gilles HPKI‐K 550
  • Heat Output: 550kW – there are back‐up oil boilers, but the woodchip boiler is the lead boiler at all times.
  • Fuel: Locally sourced woodchip.
  • Fuel Storage: 150m3 Underground bunker.
  • Fuel Delivery: Direct tip, articulated or rigid lorry.
  • Final Heat: 963.6 MWh / 963,600 kWh ‐ Primary Heat 1133 MWh / 1,133,647 kWh
  • Boiler Features: Automatic ignition, Pneumatic heat exchanger cleaning. Automatic ash removal. Integrated flying ash removal by multi‐cyclone dust separator. Data logging, remote maintenance and diagnostics by broadband.
  • System Features: Variable flow district heating system. Multiple properties heated via interface unit (HIU) for heating and instant hot water.
  • Each property individually heat metered.

The Boiler

A fully automated Gilles woodchip boiler has been installed in a new boiler house on the edge of the site. The boiler provides heating and hot water to all the buildings on the site, distributed through a network of underground preinsulated district heating mains.

Fuel Store

A 150m3 underground store, incorporating a hydraulic walking floor has been installed to make use of the local forest produce transferring fuel to the boiler as required. The store has been designed so that when it is a third full, the largest delivery can still be made, this keeps delivery costs to a minimum and making considerable savings over the life of the system. As the wood fuel is sourced locally, the net CO² produced is reduced by 256 tonnes per annum for the site.

District Heating Mains

The system was selected for its ability to heat multiple properties at one time and this is achieved through installing Isoplus insulated pipes. Energy Innovations are market leaders in the design and installation of district heating systems and they use Isoplus pipes due to their flexibility and ability to carry hot water with minimal heat loss.

Heat Meters

Full records of the heat energy (kW) transferred from the boiler to each individual property and other parts of the development are recorded to enable correct billing to be carried out for each tenant and to claim the Renewable Heat Incentive.

Special Project Requirements

As the project was within an area of outstanding natural beauty (AONB), the flue height could not be at the designed height and therefore a shorter flue and flue exhaust had to be fitted. Planning & listed building status meant that an existing footprint had to be used for the boiler house. Cost of the boiler house was increased due to the design and a higher specification of materials. As there were limitations on the footprint of the boiler house and fuel store an underground fuel store had to be built and additional costs were incurred due to the high water table on‐site.

Fuel Supply

Security of supply is always an issue. I do have concerns that biomass tends to have its own prices that are not tracked to other fuels or to the cost of production. A few tips to woodfuel users are:

1. Have your fuel supply in place at the design stage of the project.

2. Treat your fuel supplier as a project partner.

3. Always use EU standard fuels.

4. Install a fuel system so that more than one company is capable of delivering. e.g.. walking floor, tipped, hi‐tip, blown or bags.

5. Use industry standard delivery fittings and pipe sizing.

6. Shop around for your fuel; the delivery distance will have a big influence on the price fuel. The fuel supply sector is still growing and a more local supplier may be able to provide quality fuel at a reduced cost.


Design Process




Green Lifestyle



Client Feedback

Johnny Gooderham from Snape Maltings said, “English Heritage recently named the Snape Maltings Conservation Project as one of the best in England. We are very pleased that we now have such an energy efficient heating system up and running. Reducing our carbon footprint on such a historic site was always going to be a challenge, this boiler using woodchip from local forestry, is doing just that… we would recommend others to use biomass for heating and hot water on district heating projects such as ours.”


Underground fuel storage is the most expensive storage option. Installation costs and

payback times will be reduced by using above ground fuel storage methods


Suppliers and Professional Services Used

To see this or other biomass projects in Suffolk please contact:

Gary Battell ‐ Woodland Advisory Officer

Suffolk County Council

Economy, Skills & Environment

Endeavour House B2‐F5‐43

8 Russell Road




Tel: 01473 264 776

Mobile: 07894 251 084