Selecting Power Generation Equipment

This is one of the most important considerations for our customers. Gas engine solutions offer very competitive installed costs/kW for projects that are just a few hundred kWs to those with multiple MW installations.

You’ll want to determine how much gaseous fuel your power plant will consume. Typically, 75% of the cost of energy produced is the cost of fuel, so efficiency is very important.

Jenbacher* gas engines are highly efficient, with the maximum electrical efficiency reaching well over 45%. Jenbacher equipment works in cogeneration solutions, efficiently converting the primary energy of the gas fuel into electricity and heat. In cogeneration mode, overall efficiency can reach even higher than 90%.

The total production time of Jenbacher gas engine power plant components plus the time for construction and commissioning usually falls between 8 and 16 months (time to Commercial Operation Date). Your time to COD could be even shorter if units are in stock. That means you can start receiving the economic benefits of onsite power generation with gas engines in a fairly short time.

When INNIO designs our solutions, we take into account our equipment’s eventual delivery to the installation sites. Our solutions can be installed in buildings or can be packaged into easily constructed modular structures. For example:

- Jenbacher Type 2, 3, 4 and 6 engines are packaged in standard containers measuring 2.4 and 3 meters wide.
- Jenbacher 920 FleXtra engines typically are built in a very modular design.

The modularity of our solutions makes project logistics easier. In addition, ready-to-use solutions allow you to accelerate the commissioning of the project and effectively scale up your power plant in the future.

Another very important factor in determining the choice of technology for a power plant is operational expenditures associated with the installed equipment.

You should consider such aspects as: maintenance intervals, works and spare parts cost, downtime during repairs, and equipment lifecycle duration before overhaul. We recommend customers compare the cost of the equipment’s entire lifecycle.

To minimize equipment downtime during major repairs, Jenbacher has developed long block and short block solutions that deliver overhauled engines that meet the quality and performance standards of our new units. Reach out to one of our experts to learn more.

Jenbacher also offers multi-year service contracts and Asset Performance Management tools. These help to reduce the need for spare parts and can predict service events, lowering costs throughout the engine’s lifecycle.

Definitely take this factor into account, especially if you are not going to operate your equipment 24/7 and plan to stop it periodically.

Make sure to check the maximum possible start/stops within the equipment’s lifecycle, which is stipulated by some equipment manufacturers. When such limits are surpassed, the actual equipment lifecycle can be shortened, meaning you’ll need an earlier overhaul. In some cases, power generation equipment manufacturers might even require additional service payments for every start.

If you consider using gas engines, our experts can advise you whether this factor is applicable for your particular project depending on planned start/stop events frequency.

Our experts can help you select equipment that suits your requirements by analyzing your project’s load profile. Jenbacher's gas engine product line covers a wide range of power outputs—from 0.3 to 10.6 MWs—we can help you find a solution that fits your specific application.

You also should determine how quickly you need your power generation equipment to reach a given capacity—a factor that is especially relevant for such applications as data centers, medical institutions, oil & gas, and grid firming/peaking applications.

The standard startup time for Jenbacher gas engines is 5 minutes from initializing the start to reaching full output. Some Jenbacher Type 4 engines can reach full output in less than 2 minutes and a special version of our J620 engine achieves a full 3 MW of electric output in less than 45 seconds. The J920 FleXtra, our 10.6 MW engine, can reach full power in less than 3 minutes.

Time to full power output may vary depending on technology and model. In some cases, it could take longer than 10 minutes to reach full power and for complex application it could take even more than 30 minutes. We suggest to look closer at this aspect if maneuverability is an important factor for your project.

If you plan to run equipment at partial load for significant periods of time, you’ll want to seriously consider potential efficiency reduction issues. Equipment usually reaches the nominal efficiency parameters at rated power output, but at partial load, efficiency may be lessened. For Jenbacher gas engines, this efficiency decrease is quite moderate, while for other types of power generating equipment, it can be much more significant.

Moreover, our experts can consult with you about selecting engines that best fit your load profile, thereby decreasing periods of partial equipment load.

The ambient conditions under which you will operate your equipment can have a big impact on its actual power output capacity. In other words, under certain conditions your power output may be much lower than the rated power level. Pay attention to this factor if you plan to operate the equipment at high temperatures and/or at an altitude significantly above sea level.

Our gas engines typically provide full output up to 86°F and more. Our gas engines keep rated power outputs at high altitude above sea level. Contact our experts to find out more.

While gas turbines can achieve higher efficiencies than gas engines in combined cycle applications, gas engines offer higher electrical efficiency in simple cycle applications. CCGT setups typically require longer start-up times, which may make gas turbines a good choice for continuous base load power generation. On the other hand, gas engines tend to have better efficiencies at partial load, making them more suitable for applications with variable load profiles or for peaking power plants that need to ramp up and ramp down quickly. By cascading gas engines, plant efficiencies close to the nominal value can be achieved across a very large plant load range.

Source: INNIO Group

Gas engines can start and stop quickly, and they can ramp up and ramp down their power output rapidly. This makes them a good choice for applications requiring a high degree of flexibility, such as grid balancing or integration with renewable energy sources. Gas turbines, especially larger units and CCGT applications, require longer start-up and restart times.

Source: INNIO Group

Gas engines offer greater fuel flexibility and can operate on a wide range of gaseous fuels, but the specific fuel handling requirements can vary.

Gas turbines are available in various sizes, from small microturbines to large industrial units. This makes them suitable for a wide range of power generation applications, from distributed generation to large central power plants. Although gas engines generally are found in small and mid-size power generation applications, they can be easily scaled up in size thanks to their modularity and are therefore also suitable for larger central power plant applications.

Gas turbines, in general, are more sensitive to changes in fuel gas pressure. If the pressure is too low, it can affect the combustion process and reduce the efficiency and power output of the turbine. On the other hand, gas engines usually operate effectively over a wider range of gas pressures. Absolute gas pressure requirement is higher for gas turbines, especially at locations with low gas pressure (e.g. at distribution grids) the need for a gas compressor greatly increases parasitic loads for gas turbines.

Gas engines generally have a lower upfront capital cost compared to gas turbines. They may require more frequent maintenance than gas turbines, but these tasks generally are simpler, therefore less costly and require shorter downtimes. Gas turbines have a higher initial CAPEX, though can operate for longer periods between servicing, but the maintenance tasks can be more complex and more expensive with extended downtimes. With proper maintenance, both technologies can have a similar lifespan.

Gas engines and gas turbines typically have low emission values. However, further decarbonization is possible with additional emission control technologies such as SCR systems or by using carbon-neutral fuels like green hydrogen.

As the altitude increases, the air becomes less dense, which can reduce the power output and efficiency of both technologies. However, gas turbines generally are more affected by changes in altitude than gas engines. The two-stage turbocharging technology of gas engines enables stable power output even at higher altitudes. A capability that presents challenges for turbine technology to achieve.

Although higher ambient temperatures can reduce intake air density, which can, in turn, reduce the power output of both technologies, gas engines have significantly better performance than gas turbines at hot ambient temperatures. Gas turbines draw in large amounts of air for combustion, and temperature directly affects the density of this air. With control systems, the fuel-air mixture and ignition timing can be further enhanced to compensate for these changes, helping to maintain performance. Gas turbine power ratings are typically given as per ISO Standards at 15°C ambient temperature, and gas turbine technology specifies power output at ISO standard at 25°C. Two-stage turbocharging technology allows gas engines to run at full load power output at ambient temperatures well above 45°C. Through simple turbo charger adjustoment improved performance at high ambients can be achieved with gas engines whereas turbine technology needs to rely on active air inlet cooling, which involves additional costs and also consumes valueable resources like water.