In-depth guide CTG012 Biomass heating A practical guide for potential users Contents Preface 01 Executive summary 02 Biomass as a low carbon energy source 02 The need for biomass heating 02 Biomass fuels and heating systems 03 Implementing a successful biomass system 03 Part 1 – Introduction 07 1.1 What is biomass? 08 1.2 Why is biomass a renewable and low carbon source of fuel? 08 1.3 Why use a biomass heating system? 09 Part 2 – Technical manual 15 2.1 Biomass fuels 16 2.2 Biomass heating systems 36 Part 3 – Implementation guide 49 3.1 Initial assessment 52 3.2 Detailed feasibility 53 3.3 Procurement and implementation 72 3.4 Operation and maintenance 80 Glossary 84 Appendix A – Conversion factors 86 Appendix B – Basic calculations 88 The Carbon Trust would like to acknowledge the support and input of the following organisations and individuals in the preparation of this guide: Biomass Energy Centre, Black & Veatch Ltd., Buro Happold Ltd., Peter Coleman (AEAT Ltd.), Department of Energy and Climate Change, Econergy Ltd., Forest Fuels Ltd., Forestry Commission, Andy Hall and Geoff Hogan (Forestry Commission), Anthony Haywood (Cwm Rhonda NHS Trust), Imperative Energy Ltd., Invest Northern Ireland, Richard Landen, Ali Nicol, Walter Poetsch (BSRIA), RegenSW, Gideon Richards (CWP Ltd.), Andrew Russell (Mercia Energy), Scottish Government, South West of England Regional Development Agency, Daniel Sullivan (Optimum Consulting), Welsh Assembly Government and Wood Energy Ltd. www.carbontrust.co.uk Biomass heating: A practical guide for potential users 01 Preface In 2005, the Carbon Trust’s Biomass Sector Review1 highlighted the significant potential of biomass heating in the UK. It showed that carbon savings of up to 20 million tonnes of CO2 per year could be achieved using UK biomass resources alone. It also identified that using biomass for heating typically gives the most cost-effective carbon savings of all uses of biomass and that this is particularly the case for small-to-medium scale applications (100 kWth-3MWth). Recognising the potential impact of biomass heating The information and processes laid out in this guide will in this range for commercial and industrial applications, also help organisations adopt ‘best practice’ approaches the Carbon Trust launched the Biomass Heat Accelerator and avoid common errors when installing biomass (BHA) in 2006. By working with existing biomass heating heating systems. The guide should help users to design, projects across the UK, the BHA has identified that a lack procure, implement and operate successful, cost-effective of customer knowledge and understanding of biomass biomass heating solutions and achieve significant heating technology is a significant barrier to wider uptake. carbon savings. This guide, prepared with the assistance of Black & Veatch Ltd., is the first major publication from the Biomass Heat Accelerator and is intended to provide The Biomass Heat Accelerator practical guidance to businesses and public sector The Biomass Heat Accelerator is one of the organisations considering using biomass as an alternative Carbon Trust’s Technology Acceleration projects source of heating for space, hot water and/or process which aims to accelerate the uptake of this low heat. The guide focuses on existing, conventional carbon source of energy. biomass combustion equipment, in the 100kWth-3MWth To achieve this, the Biomass Heat Accelerator is size range, that use solid fuels such as wood chips, working with a range of the UK’s leading installers pelletised biomass fuels and straw. However, much of and manufacturers of biomass heating equipment the information in this guide will also be of relevance to reduce the total cost of projects. The Biomass to those involved with other types of biomass projects Heat Accelerator is also working to reduce risks (e.g. biomass CHP schemes). in the fuel supply chain through quality assurance The first section of the guide introduces the concept and information provision. of biomass as a low carbon source of fuel and the key More broadly the aim of the project is to increase benefits of its use. It also covers some of the high-level awareness and understanding of biomass heating policy and market aspects of biomass use in the EU and technology amongst the customer base as a lack the UK. of this presently restricts wider market uptake. The second section provides a detailed technical Visit: www.carbontrust.co.uk/biomass for more overview of the properties of biomass fuels and typical information on the Biomass Heat Accelerator. biomass heating equipment. The third section contains a process guide covering details of the steps required to take a biomass system Throughout this guide, the term ‘site owner’ is used from initial concept to full implementation. Although to mean an individual or organisation considering this is not intended to be definitive, and individual implementing a biomass heating system at a specific circumstances and projects will vary, the section is site. However, the guide will also interest project intended to help potential site owners approach such developers, energy managers, those acting on behalf projects in a logical, structured manner. of clients to help them specify and procure biomass heating systems or other interested stakeholders such as government bodies. 1 http://www.carbontrust.co.uk/publications/publicationdetail?productid=CTC512 02 Executive summary Executive summary Biomass as a low carbon energy source In June 2008, the Government’s Renewable Energy Strategy consultation proposed that under one possible Biomass is a form of stored solar energy and is available scenario 14% of the UK’s heating may need to come in a number of different forms. These include wood, from renewable sources by 2020 for the UK to meet its straw, energy crops, sewage sludge, waste organic share of the EU 2020 target for total renewable energy. materials and animal litter. Given that less than 1% of UK heat demand is currently Although burning biomass releases carbon dioxide met by renewable sources, this implies a dramatic and to the atmosphere, this is offset by the carbon dioxide rapid transformation in the way heat is provided over the absorbed in the original growth of the biomass, or next decade. To help deliver this step change in renewable captured in the growth of new biomass to replace the heat the Government took powers in the 2008 Energy materials used. As a result, using biomass for heating Act to establish a ‘Renewable Heat Incentive’ (RHI) to results in very low net ‘lifecycle’ carbon emissions give financial support to those generating renewable relative to conventional sources of heating, such as gas, heat. An overview of the RHI appears on page 66. heating oil or electricity. Of all possible renewable heating solutions, biomass has the potential to deliver some of the most significant The need for biomass heating and cost-effective carbon savings, particularly for commercial and industrial applications. In addition to Heat in all its forms presently accounts for nearly half carbon savings, biomass heating also offers significant 2 of the UK’s carbon emissions . The UK has a legal benefits for users, including operational fuel cost requirement to reduce carbon emissions by at least savings and reduced fuel price volatility. It can also 26% by 2020 and 80% by 2050 (against a 1990 baseline) stimulate local economic activity by creating fuel 3 under the Climate Change Act . Meeting these targets supply chains and make use of resources that would will require a major shift away from fossil fuel heating otherwise be treated as waste and sent to landfill. systems to lower carbon forms of heating. 2 http://renewableconsultation.berr.gov.uk/consultation/chapter-4/executive-summary/ 3 http://www.defra.gov.uk/environment/climatechange/uk/legislation/index.htm Biomass heating: A practical guide for potential users 03 Biomass fuels and heating systems Implementing a successful biomass Biomass heating is a mature, proven technology and system has been used successfully for many years in countries The Carbon Trust’s experience of working with existing such as Austria, Finland and Denmark. The two key biomass heating installations has shown that there is elements of a biomass heating solution are the fuels currently a wide variation between common practice and the heating system. and best practice. The most commonly used sources of biomass heating In order to successfully design and deliver a high fuels are virgin wood, certain energy crops, industrial performing, cost-effective biomass heating solution it is wood residues and certain agricultural residues. Biomass essential that site owners follow a structured approach fuels are typically delivered as woodchips or wood to system implementation. pellets, but can also be in other forms such as logs or straw bales. Fuel is normally provided by one or more The key phases of this approach are as follows: dedicated suppliers, but on-site materials can also be used in some situations, such as on farms. The key characteristics of a biomass fuel include its Initial assessment moisture content which affects its energy content (the In this phase the aim is to understand quickly whether calorific value), and the particle size/grade. Factors which biomass is likely to be an appropriate, alternative affect fuel costs include the type of fuel and its associated heating solution for the site before embarking market availability, the quality of the fuel, the form the on a detailed feasibility study and engaging with fuel is delivered in and the proximity of the fuel source potential suppliers. This phase typically involves to the point of use. a basic assessment of site suitability, a basic economic appraisal and a review of other potential, The heating system itself consists of biomass boiler non-financial benefits. plant, ancillary equipment (such as control systems flues and pipe work), and infrastructure to receive and store fuel and transfer it to the main boiler unit.