2G Blog

August 23, 2021

What Is Combined Heat and Power (CHP) and Cogeneration? How It Lowers Energy Costs

It is a fact of modern life that everyone needs electricity. It’s crucial to run manufacturing plants, hospitals, airports, and to heat our homes. Without it, society can’t function. Yet it’s also a fact that traditional ways of generating energy are harmful to the Earth, the environment, and health. To add insult to injury, prices can be cost prohibitive, and weather, occasional power outages, and natural disasters can have severe disruptions to everyday life. 

It is for these reasons that it’s becoming increasingly popular to look for alternative sources of energy. One of them is combined heat and power (aka cogeneration). But what, exactly, is it? How does it work? What are the benefits? And how can you generate such a type of energy? 


What Is Combined Heat and Power? 

Combined heat and power (CHP) is an energy generating technology that works twofold: It creates electricity and captures the heat generated by it to then use it as thermal energy. This allows for the captured calefaction to heat water and create steam. In a nutshell, it’s an energy efficient way of powering large-scale operations, such as manufacturing plants, airports, college campuses, apartment buildings, and hotels. 

Depending on the need, a CHP power system installed on a site can be within a building, or pre-package in its own housing. They can be installed singularity or several of them can work together to produce energy for an entire geographical location. 

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How Does CHP (aka Cogeneration) Work? 

Traditionally, electricity is produced from the combustion of fossil fuels (such as crude oil, natural gas, shales, bitumens, and coal). All of these fuels are extracted from layers of rock under the Earth’s surface through mining and drilling. They are then burned in a furnace to release heat energy. This heat boils water, which in turn, creates steam. This steam powers steam turbines, which drive generators, and these generators create electricity. 

The problem with this method is that it wastes energy throughout every single step. And since this is the main source of energy for most of the planet, it’s done extensively and has caused significant environmental pollution. 

CHP reduces this impact by capturing what would normally be wasted heat and using it to either heat other things or use the heat in a chiller to create cooling. 

how cogeneration and CHP produce power

To better help you understand its inner workings, it’s important to go over the main components: 

  • The prime mover is the engine that powers the technology. CHP can work with different ones, such as gas or steam turbines, combustion engines, fuel cells, or combined cycle gas turbines, to name a few. (2G Energy offers 100% hydrogen reciprocating engines — the only company to do so). 
  • The generator converts energy into electricity. It can be grid controlled or self controlled. 
  • The heat recovery unit captures heat that escapes from the power generation process.

CHP technology works by going through the following steps: 

CHP technology process

  1. Fuel is added to the technology (the combustion turbine or reciprocating engine, which both have a heat recovery unit). 
  2. The CHP engine burns fuel through the combustion process. 
  3. A power generator is connected to the engine. 
  4. The electricity produced can be put on the electrical grid or used by the CHP operator themselves.
  5. As the engine releases exhaust, a converter extracts pollution. Heat is also collected from the exhaust and from the engine itself as it creates heat while it is running.
  6. The exhaust gas heat exchanger absorbs the hot exhaust air created in the engine and passes it on to a liquid consisting of glycol.
  7. The heat is then extracted from the hot glycol and passed on to the customer's heating circuit.
  8. The heat can also be sent to an absorption chiller to produce cooling.

While these processes also use fossil fuels, they reduce the amount needed to generate energy. Therefore, they contribute to less land degradation and reduce air pollution. As an alternative, CHP technology also works with biogas (fuel produced from decomposed organic matter, such as animal manure and/or food scraps), as well as with hydrogen. 

Benefits of CHP and Cogeneration 

There are several benefits to using cogeneration over traditional sources of energy. These include: 

1. Versatility

CHP technology can be used with renewable energy, such as RNG, biogas, and hydrogen, as well as with fossil fuels. And in addition to powering industrial and manufacturing facilities, it can be used to efficiently generate power for commercial buildings, municipal landfills and water treatment plants, residential developments, and institutions (such as hospitals, college campuses, and prisons). 

2. Energy Efficient

Cogeneration creates thermal energy out of heat that would normally be wasted during the power generation process. And because it does so concurrently as it also creates electricity, it works more efficiently than producing each energy source independently. 

3. Cost Effective

Since combined heat and power technologies produce two types of energy at once — and reuses escaped heat to create even more energy that can be used to heat water, cool spaces, or create steam — it significantly drives down operating costs. 

4. Power Reliability

Cogeneration makes operations less dependent on traditional power grids. This means that in the event of a power outage, there’s no downtime, as it continues to generate a high energy supply. 

5. Reduces Pollution 

Cogeneration reduces pollution because it burns methane instead of letting it go into the environment (which would cause heat to become trapped in the atmosphere and contribute to global warming). This makes it a much more efficient way of generating energy. Also, a component called the carbon dioxide scrubber absorbs most CO2, decreasing carbon emissions. And if the technology runs on hydrogen, it has zero emissions. 

Combined Heat and Power Systems

Different types of operations have specific energy requirements. Regardless of what these may be for you, CHP provides a reduction in energy costs and more environmentally friendly technology.

Options range from small power plants with an electrical output of up to 60kW to larger ones for high power consumption above 500kW. You can also interconnect multiple units for an even greater power output. 

They can also be installed within existing buildings or heating systems or set up separately in a container or engine room. In addition, they can be set up with different types of insulation and low noise emission, depending on local conditions and type of operations. 

In addition, CHP technology is compatible with different sources of energy, including: 

2G Energy’s CHP Systems Support Your Energy Needs

2G Energy offers a wide array of CHP solutions that provide from 50 kW to 2,500kW. We also have an extensive portfolio of successful CHP projects in the U.S., Canada, and Europe, and have installed over 6,500 systems worldwide. 

Contact us to learn more about how CHP can transform your operations and significantly reduce your energy costs. 

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