Gas engine and gas turbine technologies: Overview US

Gas engine technology

These internal combustion engines operate on gas fuels to generate electricity. They are widely used in power plants, industrial facilities, and other sectors where reliable, on-site power generation is needed.

What is the typical gas engine power plant scope?

• Gas engine: The heart of the generator set (genset), it operates on the principle of internal combustion, where either a gas-air mixture is ignited or fuel is injected via a direct air-injection system into the cylinders to produce mechanical energy.
• Generator: Coupled with the engine, the generator (or alternator) converts mechanical energy produced by the engine into electrical energy. It consists of a spinning rotor within a stator that creates an electromagnetic field, inducing a current.
• Control system: The control panel, along with associated software, monitors and controls the genset operation. It enables the genset to operate safely, efficiently, and reliably – starting and stopping it, regulating the output voltage, and protecting the genset from overloads and other faults.
• Heat exchangers: By capturing the waste heat produced during electricity generation, the system’s overall efficiency is improved significantly. This otherwise wasted heat is repurposed for on-site heating, district heating, industrial processes, or even cooling (via external absorption chillers).
• Auxiliary equipment: This includes cooling, exhaust, fuel, start-up, and other systems.

These components work together to enable the genset to operate efficiently and reliably, providing a steady supply of electricity and heat, if necessary.

How does the gas engine work?

The process begins with the intake of a mixture of air and fuel – such as natural gas, biogas, or other gas fuels – into the engine’s combustion chamber. The mixture then is compressed by a piston and ignited by a spark plug. The resulting explosion drives the piston downward, turning the crankshaft and generating mechanical energy. This mechanical energy then is converted into electrical energy by an alternator. Dedicated engine versions also use direct port injection technology to improve both the combustion of fuels such as hydrogen and the engine’s transient performance.

INNIO Group offers a wide range of gas engine solutions that are designed for excellent efficiency, reliability, and flexibility. These engines can be used in a variety of applications, including power generation; CHP or cogeneration; and combined cooling, heat, and power (CCHP) or trigeneration.

Gas turbine technology

A standard gas turbine power plant has a scope similar to that of a gas engine plant. However, in this case, the gas turbine unit converts the energy from burning gas into mechanical energy to spin the turbine. This technology is widely used in power plants and industries due to its efficiency, flexibility, and reliability.

How does the gas turbine work?

• Air intake: The process begins with the intake of air, which is compressed, usually with a centrifugal or axial compressor.
• Fuel combustion: The compressed air then is mixed with fuel – typically natural gas or diesel – in a combustion chamber. The fuel-air mixture is ignited, producing high-temperature, high-pressure gas.
• Power generation: This high-pressure gas then is directed toward the turbine blades, causing them to spin. The spinning turbine is connected to a generator, which converts the mechanical energy into electrical energy.
• Heat recovery: Exhaust heat from the turbine can be used in heat exchangers to generate hot water or steam for various applications, a process known as cogeneration. In combined cycle gas turbine (CCGT) power plants, heat from the exhaust gas is used to produce steam, which drives a steam turbine to generate additional electricity. These processes significantly improve the power plant’s overall efficiency.

Gas engine vs. gas turbine comparison table

Choosing the right power generation technology

The specific requirements of your power generation project will determine which technology – gas engine or gas turbine – you ultimately choose. Each has its own strengths and weaknesses. A thorough analysis is essential to identify the best solution for your power generation needs. Use the table above and consider the following factors in your decision:

The Jenbacher solution

Jenbacher 50 MW power plant

Advantages of Jenbacher engine technology:

• Efficiency: Gas engines can reach high levels of efficiency, particularly in combined heat and power (CHP) systems and high ambient temperatures and altitudes.
• Flexibility: Because they can be started and stopped quickly, gas engines respond efficiently to changes in power demand. In addition, gas engines can work in partial load mode as needed and are scalable in size.
• Environmental impact: Gas engines also can run on a broad range of energy sources, including renewable fuels such as biogas, industrial by-process gases, and even hydrogen of up to 100%.
• Modular solutions: The modular design and high engine reliability help increase uptime and low maintenance requirements of the power plant.
• Advanced digital solutions: myPlant AI-powered platform for remote monitoring and predictive analytics, helping to enhance performance and efficiency of gas engines fleet.
• Energy transition support: With the increasing share of renewable energy sources (RES) and decentralized power generation solutions, gas engines play a significant role in the energy transition by providing a flexible, efficient, and reliable power to the grid, ensuring stability in combination with variable renewable energy sources.

With more than 13,000 of our Jenbacher CHP systems delivered around the globe, INNIO Group is a global technology leader in engine-based power generation. Our Jenbacher experts can work with you to determine if gas engines are the right choice for your power generation project. And, with our wealth of experience, we can dive deeper into the costs and benefits of your project to find the solution that best meets your specific needs.

A Jenbacher cogeneration plant consists of the power generation unit with an engine and a generator along with heat exchangers to take advantage of the heat resulting from the combustion process. The energy systems use all related heat sources such as the engine cooling water, lubricating oil, the air/fuel gas mixture and the exhaust gas. Water temperature levels of 100°C and more can be achieved, making Jenbacher CHP and CCHP solutions highly flexible.