Harnessing the power of combined heat and energy for a cleaner, more efficient energy system
In the quest for a more sustainable and efficient energy future, cogeneration stands out as a powerful yet often overlooked solution. Also known as Combined Heat and Power (CHP), cogeneration is the simultaneous production of electricity and useful heat from a single fuel source.
Imagine a facility that uses natural gas not only to generate its own electricity but also captures the excess heat that would normally be wasted—using it for industrial processes, heating buildings, or even district heating.
This dual-purpose approach makes cogeneration significantly more efficient than separate production of heat and power.
For Canada, a country with vast energy needs from its industrial sectors, cogeneration represents a critical pathway toward reducing greenhouse gas emissions while maintaining economic competitiveness. As of 2021, energy-intensive industries accounted for approximately 40% of Canada's total energy demand and a similar proportion of its greenhouse gas emissions 1 . Within this challenging landscape, cogeneration offers a practical solution for doing more with less energy—a crucial advantage in the transition toward a cleaner economy.
Cogeneration systems can achieve overall efficiencies of 75-90%, compared to 40-60% for conventional power generation 2 .
Multiple sectors including oil & gas, manufacturing, and mining utilize cogeneration to power their operations.
By maximizing energy output from each unit of fuel, cogeneration significantly reduces greenhouse gas emissions.
Canada's energy-intensive industries have increasingly turned to cogeneration to power their operations. Between 2005 and 2021, greenhouse gas emissions from on-site electricity generation and cogeneration at these facilities nearly doubled, reaching over 25 megatonnes of carbon dioxide equivalent 1 . While this increase in emissions might initially seem concerning, it reflects a complex story of industrial growth and the gradual transition toward more efficient energy systems.
| Industry Sector | Primary Fuel Sources | Key Trends | GHG Emissions Impact |
|---|---|---|---|
| Oil & Gas Extraction | Natural Gas (>90%) | Generation nearly doubled; tied to bitumen extraction growth | Significant contributor to sector emissions |
| Wood & Paper Products | Bioenergy (dominant), Natural Gas (growing) | Generation fluctuated with industry conditions | Bioenergy offers lower net emissions |
| Chemical Manufacturing | Natural Gas | Generation increased | Contributed to overall emissions growth |
| Metal/Non-metal Mining | Natural Gas | Generation increased | Contributed to overall emissions growth |
| Other Manufacturing | Hydroelectricity | Hydro generation lower in 2021 vs. 2005 | Lower emission profile |
Source: Based on data from citation 1
At the heart of cogeneration's efficiency advantage lies waste heat recovery—the process of capturing and reusing thermal energy that would otherwise be discarded into the environment. In conventional power generation, as much as 40-60% of the energy content in fuel is lost as waste heat. Cogeneration systems capture this thermal energy for productive use, potentially reaching overall efficiencies of 75-90% 2 .
The basic principle involves capturing heat created in one part of a facility and reusing it in other applications. The key component determining how much heat can be recovered is the heat exchanger technology used. Modern compact heat exchangers can recover up to 25% more energy than traditional shell-and-tube designs at comparable cost, due to their five times higher heat transfer efficiency and lower capital expenditure 2 .
Overall energy efficiency comparison between conventional power generation and cogeneration systems
A compelling example of waste heat recovery comes from Hamburg, Germany, where surplus heat from a copper production plant is transferred to district heating using gasketed plate heat exchangers. This system reuses approximately 160,000 MWh of thermal energy per year—enough to heat 3,400 apartments while reducing carbon dioxide emissions by an estimated 20,000 tonnes annually 2 .
This project demonstrates how industrial energy users can become valuable contributors to urban energy systems through cogeneration.
Cogeneration systems can be implemented through various technological approaches, each suited to different contexts and temperature requirements:
ORC technology enables recovery of low-temperature waste heat (as low as 80°C) from industrial processes and engines for electricity production. These systems use an organic fluid with a lower boiling point than water, allowing efficient energy conversion from heat sources that would be insufficient for conventional steam turbines 2 4 .
Properly configured CHP systems can achieve remarkable efficiencies. When waste heat is fully utilized, over 90% of the input energy can be recovered for productive use 2 . These systems are particularly valuable in settings with simultaneous needs for electricity and thermal energy.
| Technology | Best For | Temperature Range | Key Advantages |
|---|---|---|---|
| Steam Turbines | Large industrial facilities, district energy | High temperature (>400°C) | Proven technology, high reliability |
| Gas Turbines | Large-scale power and heat needs | High temperature (>500°C) | High power-to-heat ratio, fast startup |
| Reciprocating Engines | Smaller-scale applications, backup power | Medium to high temperature | Quick response, high electrical efficiency |
| Fuel Cells | Emission-sensitive environments, institutional campuses | Low to medium temperature | Ultra-low emissions, quiet operation |
| Organic Rankine Cycle (ORC) | Low-grade waste heat recovery | Low temperature (80-300°C) | Utilizes heat sources unusable for other technologies |
The cogeneration landscape is evolving with new technologies entering the market. Fuel cell-based CHP systems represent a cutting-edge approach that converts chemical energy directly to electricity and heat with minimal emissions. Companies like FuelCell Energy have shifted from niche projects to scalable platforms, with partnerships forming to offer turnkey, zero-carbon power generation solutions 6 .
Fuel cell CHP established commercial viability in specialized applications, such as converting biogas at wastewater treatment plants into clean electricity and heat.
The strategy had evolved toward market-wide scalability through platforms like Dedicated Power Partners—a collaboration designed to streamline project development and financing 6 .
As Canada progresses toward its 2035 clean electricity goals, cogeneration facilities are exploring various pathways to reduce their environmental impact:
Optimizing production processes and energy intensity to reduce electricity and process heat requirements per unit of output 1 .
Transitioning to lower-emitting energy sources like nuclear, bioenergy, hydrogen, or renewables 1 .
Adding CCS capabilities to existing fossil-fueled cogeneration plants to capture emissions 1 .
Canada recognizes the importance of cogeneration in its energy transition strategy. Natural Resources Canada's CanmetENERGY division conducts research and development focused on industrial process optimization, with waste heat recovery identified as a priority area 7 .
Developing tools to identify optimal waste heat recovery solutions based on a plant's overall context and energy flows 7 .
Creating electronic databases with detailed performance information on various waste heat recovery technologies 7 .
A $15 million fund established in 2023 to support hydrogen production and storage, creating foundational infrastructure for fuel cell CHP applications 6 .
Cogeneration represents a pragmatic, efficient approach to meeting Canada's intertwined needs for economic productivity and environmental responsibility.
By simultaneously generating electricity and useful thermal energy from a single fuel source, these systems squeeze maximum value from every unit of energy while reducing the carbon footprint of industrial activity.
The continued evolution of cogeneration—through more efficient heat exchangers, innovative business models like FuelCell Energy's scalable platforms, and supportive government policies—suggests its importance will only grow as Canada advances toward its climate goals.
For a country with both significant industrial energy needs and ambitious emission reduction targets, cogeneration offers a rare win-win solution: doing more with less while powering the economy and protecting the planet.