Understanding the background
In an era where the urgency of the energy transition is more pressing than ever, finding alternative solutions that optimise energy performance and yield significant consumption savings is imperative. Amidst the global drive to meet climate goals, biomass stands out as a promising and sustainable solution.
The Importance of biomass for the global energy transition
Biomass is a key driver of renewable energy production worldwide. In France, it accounts for 55% of renewable energy production, while in Finland, combined with nuclear energy, it represents 85% of total energy output. Germany and Sweden also make extensive use of biomass for its environmental and economic benefits. In the United States, biomass makes up 5% of renewable electricity generation, supported by government subsidies. In Asia, China and India are making significant investments in biomass technologies to meet their energy needs and reduce their carbon footprints.
Equans, a major player in the energy sector, is committed to developing the renewable energy sector and supporting energy producers in implementing renewable energy sources in a way that is beneficial to both the cause and the parties involved. For more than 15 years, Equans has been using its expertise to help power plants successfully convert from gas to biomass.
What is biomass energy?
Biomass energy is created by turning organic materials like wood scraps, farm waste, or algae into energy we can use. There are lots of ways to do this, including burning it directly, gasifying it, or turning it into a gas through pyrolysis. These processes can also be used to make liquid biofuels like bioethanol and biodiesel.
Advantages of biomass over traditional fossil fuels
Energy from biomass offers a number of significant advantages not only over fossil fuels but over other alternative energy sources:
- Renewability: unlike fossil fuels, biomass is a renewable resource. The raw materials can be regenerated in relatively short cycles, contributing to the sustainability of the energy supply.
- Reduced emissions: burning biomass produces fewer greenhouse gases than fossil fuels, helping to combat climate change. For example, burning peat emits approximately 106 g CO₂/MJ compared to 95 g CO₂/MJ for coal.
- Waste recovery: biomass can be used to recycle organic waste, reducing the amount of waste sent to landfill.
- Energy independence: local use of biomass can reduce dependence on imported fossil fuels, thereby increasing regional energy security.
- Versatility: biomass can be converted into different forms of energy, including electricity, heat and biofuels, providing a flexible energy solution.
- Base load power: unlike solar and wind energy, which are intermittent, biomass can provide a consistent and reliable energy supply, ensuring stable baseload power generation.
Gas to biomass conversion in power plants
The conversion of gas-fired power plants to biomass is a complex but feasible technical process. The technical aspects of this conversion include several important steps to ensure an efficient and sustainable transition:
Adaptation of equipment
Boilers and other equipment need to be adapted or replaced to run on biomass fuels. Boilers designed to burn natural gas are not suitable for burning solid biomass such as wood chips or pellets. They must therefore be converted or replaced with boilers that are suitable for burning biomass and that allow efficient combustion and energy production.
Supply management
Ensuring a stable and sustainable supply of biomass is vital for the continued operation of the plant. This includes establishing reliable and sustainable supply networks to ensure that raw materials are continuously available in sufficient quantities. It is also important to establish appropriate storage facilities to keep the biomass dry and free from contamination.
Fuel handling and storage
Biomass fuels such as wood chips require special handling and larger storage areas than natural gas. These areas must be designed to keep the biomass dry and free from contamination, which is essential for efficient combustion and to reduce the risk of fire.
Boiler modifications
The plant's boilers must be replaced or upgraded to burn solid biomass instead of gas. This requires the installation of combustion systems adapted to the biomass, capable of compensating for variations in fuel quality and humidity, while ensuring complete and efficient combustion.
Treatment of emissions from biomass installations
Although the use of biomass for energy production is cleaner than fossil fuels, it is not free of pollutant emissions. Thanks to advanced technologies and the expertise of specialist partners such as Equans, it is possible to install effective emission treatment systems that minimise the environmental impact of biomass energy production while meeting performance and regulatory requirements.
Emission controls
New kilns and advanced filters and scrubbers are being installed to control the increased emissions from biomass, such as particulates and gases. Although biomass generally produces lower CO₂ emissions than fossil fuels, it can produce higher levels of particulates and other air pollutants. This requires the installation of advanced air pollution control equipment to capture and remove these pollutants before they are released into the atmosphere.
Ash treatment
Biomass combustion produces ash, which requires new collection and disposal systems. This ash may contain nutrients and heavy metals. Its disposal must be carefully planned to avoid environmental pollution and to allow its possible use as an additive in agriculture or for other industrial applications.
Modernisation of systems
The power plant's control systems will need to be upgraded to handle the new type of fuel and to ensure smooth integration into the existing power grid. This includes the installation of monitoring and control software and hardware capable of handling fluctuations in the quality and composition of the biomass fuel.
Training
Training of personnel for the operation and maintenance of the new biomass plants is necessary to ensure the smooth and efficient operation of the plant. This training will include the new operating procedures, safety measures specific to the handling of biomass, and the maintenance and management of the newly installed equipment.
Equans' contribution
Equans plays a crucial role in these transitions by contributing its technical expertise and integrated solutions that cover:
- Design and engineering: Equans helps to plan the necessary changes to existing plants to ensure a smooth and efficient transition to biomass. Equans provides design and engineering expertise to develop tailor-made solutions for the specific needs of biomass power plants. This includes the selection of the most appropriate technologies and their efficient integration into existing systems.
- Installation and commissioning: The company supervises the installation of new plants and ensures that they are commissioned so that they function properly from the outset. The company is involved in the installation and commissioning of abatement systems and ensures that the systems operate effectively from start-up.
- Maintenance and optimisation: Equans provides regular maintenance and optimisation services for abatement systems to ensure their continued performance and adaptation to new environmental regulations.
Training and support: Equans provides detailed training programmes for plant personnel to ensure a thorough understanding of new systems and best practices in their management. Equans also provides training programmes and technical support to plant operators to help them understand and manage abatement systems efficiently and safely.
Sisseln Case Study
Is the Sisseln project, Equans was involved in the conversion of a gas-fired power plant into a wood-fired CHP plant using advanced technologies, including fixed sensors to measure the moisture content of the biomass supplied. The conversion resulted in a saving of 50,000 tonnes of CO2 per year and an 86% increase in production efficiency.
