Introduction
What makes Bioenergy with Carbon Capture and Storage (BECCS) a promising option for removing carbon emissions at scale?
One of the biggest draws is its ability to be integrated into industries that emit biogenic CO2. The capture and storage of carbon originating from biomass makes this process completely net negative, meaning facilities that integrate BECCS remove more CO2 from the atmosphere than they produce. Pulp and paper mills are a prime example, but they aren’t the only viable source of biogenic CO2 emissions in industry.
Combined heat and power (CHP) plants already operate to sustainably process and produce energy, but they may in some cases have the potential to become entirely net-negative. Because these systems produce electricity and repurpose heat that’s released, CHP plants are considered an eco-friendly option for power production. Overall, the sector remains significantly lucrative with a global market size valued at $30B+ in 2022 and is “expected to surpass around $46B by 2030.”
How it Works: Dual Generation Process
Combined heat and power is also referred to as cogeneration for its ability to generate two forms of energy: thermal and electrical. This system is called the dual generation process and represents an efficient and sustainable approach to energy production. At its core, this system harnesses the potential of a single energy source, typically natural gas or biomass, to generate both electricity and thermal energy.
In the case of BECCS implementation, and the focal point of Biorecro project development with CHP, only facilities with the combustion of biomass in waste incineration processes are considered as the source of CO2 in this case is biogenic.
Traditional power plants waste a significant amount of heat during electricity generation, whereas CHP plants optimize energy utilization by capturing and repurposing the excess heat produced in the process. This surplus heat can be utilized for various purposes, such as heating buildings, providing hot water, or driving industrial processes. By effectively squeezing more energy out of the same input source, CHP plants not only reduce greenhouse gas emissions but also enhance energy resilience and lower overall energy costs.
CHP Efficiency
In comparison to conventional electricity and thermal energy production, CHP plants need less fuel to produce energy. Moreover, when electricity travels through an extensive network of power lines some energy is lost during that transmission due to resistance in the wires.
By producing electricity on-site, CHP plants bypass this loss entirely. Avoiding this kind of loss also means less fuel is consumed during electricity production. Traditional power generation systems, which often rely on fossil fuels like coal or natural gas, produce electricity and thermal energy separately, leading to substantial energy waste.
“By capturing and using heat energy that would otherwise be wasted, CHP systems operate far more efficiently than grid electricity and on-site heating.” –US Environmental Protection Agency
While CHP plants alone offer substantial environmental benefits, it’s worth noting that their positive impact can be further amplified by integrating Bioenergy with Carbon Capture and Storage (BECCS) into the process. The supplementary measures of BECCS have the potential to elevate the sustainability of CHP plants by capturing and storing carbon dioxide emissions.
Fuel is introduced into the furnace, initiating a process in which water circulating within the boiler’s walls is heated to produce steam. This high-pressure steam is then utilized to drive a turbine, subsequently generating electricity within the generator for broader distribution. This configuration may vary depending on the facility, but in general steam is what drives this process.
Any excess heat generated during the electricity production process is systematically captured and repurposed, primarily for district heating, which benefits residential and commercial spaces.
CHP Key Components
Prime Mover: The prime mover is the heart of a CHP plant, responsible for converting the primary fuel source into mechanical energy. Common prime movers include internal combustion gas turbines, steam turbines, or engines.These devices drive the generator to produce electricity.
Generator: The generator is coupled to the prime mover and transforms the mechanical energy generated into electrical power. It produces electricity that can be distributed for various uses.
Heat Recovery System: A central element of CHP plants is the heat recovery system. It captures and repurposes the excess thermal energy generated during electricity production. This recovered heat can be used for different heating purposes, such as heating in buildings or providing hot water.
Primary Fuel Sources: CHP plants are versatile and can run on a range of primary fuel sources, including natural gas, biomass, waste heat, coal, or even renewable resources like solar or geothermal energy. The choice of fuel depends on factors such as availability, environmental considerations, and the specific application of the CHP plant.
Biomass as a Requirement for BECCS: In order to implement BECCS at a CHP facility, the primary fuel source must come from biomass. The capture of CO2 from combustion of biomass as fuel is how the BECCS process is able to remove carbon from the atmosphere. More on that later in the article.
Electricity Generation Process: The electricity generation process in a CHP plant begins with the prime mover combusting the primary fuel to produce mechanical energy. The produced energy from combustion is used to rotate the generator, converting it into electrical power. Simultaneously, waste heat is generated during this process and is directed into the heat recovery system.
Heat Recovery Process: The heat recovery process is a vital aspect of CHP plants’ efficiency. It captures the waste heat produced during electricity generation and redirects it for productive use. Heat exchangers transfer the heat to a secondary circuit, where it can be used for various heating needs, such as space heating, domestic hot water, or industrial processes. This process maximizes the overall energy utilization of the system.
Disclaimer: Jämtkraft AB is not affiliated with Biorecro
BECCS Implementation
BECCS integration into Combined Heat and Power (CHP) plants presents a promising avenue to further enhance the environmental sustainability of these facilities. BECCS involves the utilization of biomass as a primary fuel source within CHP systems. The combustion of waste biomass generates both electricity and thermal energy, a process already inherent to CHP plants.
However, the crucial distinction lies in the subsequent step: BECCS incorporates carbon capture technology to capture and store the carbon dioxide emissions produced during biomass combustion. Once the prime mover of the CHP plant combusts the waste biomass, the released emissions are captured and pressurized into a supercritical fluid. This CO2 is then safely transported and stored underground, resulting in a net negative system which removes more carbon from the atmosphere than is produced. This is an important distinction to make, in comparison to CCS systems added to oil and gas combustion which are at best net zero.
At present, these already existing facilities emit biogenic CO2 as a waste byproduct from the energy production process. By implementing BECCS to capture and store this carbon, carbon removal is achieved utilizing a second tier waste stream, enhancing the sustainability of this system.
The first-tier waste stream of biomass from municipalities and industry is combusted, producing energy as well as a second-tier waste stream of biogenic CO2 which is then captured and sequestered underground. In other words BECCS at CHP facilities produces carbon removal using the waste of the waste – a highly circular and sustainable process.
By combining the efficient energy production of CHP plants with the carbon mitigation capabilities of BECCS, these integrated systems not only provide electricity and heat but also play a vital role in actively removing CO2 from the atmosphere at scale, contributing significantly to a sustainable and climate-stable future.
A depiction of how waste biomass is processed at CHP plants and captured by BECCS technology for long-term storage. CO2 from the atmosphere is stored in the physical structures of biomass via photosynthesis.
When this biomass is burned, the CO2 is then emitted from flue gasses to be captured and then subsequently stored underground using CCS technology. During this process the facility produces energy and heat from the combustion of the biomass fuel stock.
Why CHP Plants Need BECCS
The integration of BECCS operations has the ability to sequester those emissions and deliver large-scale, long-lasting carbon removal. Investing in the BECCS technology is not only required to meet the climate targets set in place by the Paris Agreement, it also requires less infrastructure in comparison to other CDR methods that can’t be integrated into existing industries. The overall economic advantages and environmental benefits of CHP plants and BECCS combined will give us a pathway to a lowered carbon footprint and stable climate.
