The question of ‘what is CHP?’ doesn’t exist in a vacuum, but as part of a larger discussion on how heating technologies can reach a more sustainable approach. For a few years now, governmental authorities, citizens and companies have been questioning the types of transformations that need to happen to attain net-zero greenhouse gas (GHG) emission goals.
As generating systems that reach carbon neutrality for heating structures remains a priority, combined heat and power stands at the center of many initiatives aiming at building more efficient and sustainable heating.
Let’s see the answer to ‘what is CHP’ exactly, the advantages of this system and its applications.
What is CHP?
CHP (or combined heat and power) refers to the technologies able to produce both electricity and thermal energy using a single source. In order to do so, CHP systems capture heat that would otherwise be wasted, in on-site power production structures. Then, the heat can be used in multiple applications, including space heating and cooling, as well as hot and chilled water among others.
Also known as cogeneration, CHP is thus able to concurrently produce electricity and thermal energy by recovering and utilizing heat that would typically be wasted. In fact, it provides an efficient counterbalance to energy waste, as the US government calculates that around two thirds of energy is wasted during generation, transmission and distribution.
Additionally, these plants can be located at individual facilities, but also be part of district energy structures and microgrids, thus creating extremely efficient distributed heat generation.
The working principle for CHP includes two configurations:
- Combustion Turbine: this option uses Heat Recovery Units and a combustion turbine (or reciprocating engine), as well as heat recovery devices to capture the heat and then convert it into thermal energy (often in the shape of steam or hot water).
- Steam Boiler with Steam Turbine: this process starts by the production of steam via a boiler, which then turns a turbine to produce electricity, while thermal energy is generated through the steam leaving the turbine.
The benefits of combined heat and power
- Resiliency: CHP has been known to provide resilient backup power when grid outages take place in the face of weather events. This is especially valuable when paired with distributed energy technologies, including certain renewable sources or energy storage systems.
- Efficiency: the US government mentions how combined heat and power structures are able to achieve efficiencies of over 80 percent (a great improvement in comparison with other conventional electricity generation options, which typically show efficiencies of around 50%).
- Renewable energy sources: combined heat and power generates efficient and reliable support for intermittent, low-grade heating renewable energy sources, including wind or solar alternatives.
- No emissions: research has verified that CO2 emissions from fossil fuels can be eliminated if renewable energy sources are incorporated.
Applications of CHP
The application of CHP continues to extend as more and more operators see it as a viable option. In fact, the same source from the US government cited above shows that CHP is currently used in over 4,700 facilities in the country.
Applications of combined heat and power structures include the generation of heat, cooling, hot and chilled water in commercial, institutional and residential buildings, as well as a multitude of industrial facilities.
Low grade heat boosting with large scale heat pumps
Residual waste heat can be used also at low temperatures for producing further high quality heat and even allowing the connection with a district heating network or used back in the process, by using large scale heat pumps. The low temperature process heat (<40ºC) can be used in the evaporator, allowing the heat pump boosting that heat energy into a high temperature output in the condenser. With the use of large scale heat pumps, by adding extra compression work we achieve a high quality heat with a high efficiency ratio taking advantage of the low quality excess heat.
How to access the right CHP system for your project
As more actors consider the incorporation of CHP systems, it’s important to consider the needs and requirements of each project in terms of availability of resources and desired aims.
In fact, in a comparative guide juxtaposing combined heat and power and heat pumps, we already mentioned that research published in 2020 by Olympios suggested CHP offer less certainties for the future in terms of high operating and distribution temperatures, as opposed to district heating alternatives using industrial heat pumps.
The conclusion when it comes to how to pick the right heating and cooling structure for your project is to have the aid of professionals in heating and cooling engineering who can offer their expertise and reach the full potential of it.
At Araner, we work to make sure each project achieves its maximum energy efficiency potential as well as meets environmental goals, being able to devise tailor-made district heating systems through our concept design, project overview, manufacturing and maintenance services.
Want to find out more about the answer to ‘what is CHP’ and see if it’s the right option for your project? At Araner, we can help you. Download our free guide about district heating alternatives (including CHP) or get in touch with us and speak directly to our team about the current possibilities in heating and cooling technologies to maximize sustainability and efficiency.