Wood-burning Biomass Boilers for District Heating Systems

Published: 25th January 2016

Wood-burning biomass boilers are ideal for district heating.

Wood-burning biomass boilers are ideal for district heating.

The cost and environmental advantages of wood-burning biomass boilers for single homes or commercial buildings can be substantial, but the benefits can be much greater when multiple properties use a district heating system. 

Such area heating systems - which still qualify for payments from the government’s Renewable Heat Incentive (RHI) scheme if wood fuel from an accredited source is used - are becoming more popular and a surprisingly large number of organisations and families could benefit from them.

What is a district heating system?

A district heating system provides heat and hot water to multiple properties. A central boiler heats water, which is then circulated around a highly-insulated network of underground pipes (known as the heat main) and distributed to the connected buildings via heat exchangers. 

Usage by each building can be measured individually for the purposes of billing or identifying areas where steps can be taken to reduce energy usage. 

Homeowners may find the idea of heating their houses via a shared system a little unusual, but most people will have some experience of them, even if they do not know it. Hospitals, university campuses, schools and blocks of flats are among the settings that they have been used in the UK, although they are much more common for residential heating in Denmark and Austria. 

What are the benefits of district heating? 

District heating systems offer a number of advantages for homeowners and building occupiers over more traditional single-dwelling alternatives. They include:

  • The availability of on-demand heat and hot water 24 hours a day 
  • Lower energy bills
  • Less space being required in the properties (they don’t need their own boiler, chimney or fuel storage)
  • Reduced noise
  • Minimal maintenance costs 
  • High safety levels
  • The reassurance of a highly-reliable source of heat

They also offer the potential for significantly reduced C02 emissions, particularly when fuel from a renewable source (such as wood from well managed forests) is used. 

Why choose wood-burning biomass boilers for district heating?

Using wood fuel is a simple way to reduce CO2 emissions.

Using wood fuel is a simple way to reduce CO2 emissions.

When buying a boiler for a single property, the initial capital cost of a wood-burning biomass system is typically more expensive than equivalent oil or gas-fired alternatives and it only becomes financially attractive once the RHI payments and fuel prices are factored in to calculate total cost of ownership.

However, the scenario is slightly different for district heating systems, as the price gap between biomass and oil or gas boilers becomes comparatively smaller as the installations get bigger. Once the running costs and RHI income are added to the calculations, wood-burning biomass boilers are often by far the most cost-effective option for district heating systems.

They are also much more effective at cutting CO2 emissions, as wood is a carbon neutral fuel (the C02 captured by trees as they grow is equal to that released into the atmosphere when wood is burned). Huge reductions are achievable from installations that use multiple wood-burning boilers and have energy outputs of more than 200kW - something that can be particularly beneficial to businesses with large premises. 

The low CO2 emissions associated with wood-burning biomass boiler based district heating systems can be a real advantage to housing developers. They help to achieve Code for Sustainable Homes compliance and with any local emissions targets. Cheap heating and hot water from an environmentally-friendly source may also impress buyers and prospective tenants. 

Where can biomass district heating systems be used?

While switching to a biomass district heating system on an existing housing estate may prove too difficult to achieve, there are a number of environments in which it is both a practical and cost-effective choice.

Typically, settings with multiple associated properties could benefit from the lower energy costs and carbon emissions of district heating, including:  

  • New housing developments
  • Social housing / privately-owned tenanted housing 
  • Holiday home developments 
  • Farms 
  • Hotels and leisure complexes 
  • Business campuses /office parks
  • Country estates 
  • Public buildings, such as council offices, universities and schools

For further information about wood-burning biomass boilers and district heating systems or to request a site visit and quote, please contact Denby Dale Energy