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The Better Bi-Fuel™ Solution

The Better Bi-Fuel™ Solution


Generac’s commitment to provide its dealers and customers with the best available products and technologies is taking another leap forward with the expansion of the company’s Bi-Fuel™ product offering to include 400 kW and 500 kW power nodes in addition to the existing 600 kW node. Standardized engines and other improvements will accompany this expansion.

The current 600 kW models now feature a Perkins 18.1 Liter engine following Generac’s announcement last December of its intention to standardize on the electronically controlled Perkins diesel engines. This will be followed over the next several months by the introduction of the 400 kW and 500 kW Bi-Fuel units, which will feature Perkins 12.5 Liter and 15.2 Liter engines respectively. Click here to download the 600 kW spec sheets.

The electronically controlled Perkins 1800 RPM engines have a reputation for performing effectively through high power density standby power applications, while also providing a lower total ownership cost through reduced maintenance and downtime. The Perkins engines will continue to provide a best-in-class ownership experience while offering enhanced value over previous engines.

The expanded Bi-Fuel family will utilize many of the current and well-proven gas train components, as well as the existing control system, and will be available with all current configurable options. However, upgrades in the frame, gas flow sensors, controls module and flex hose connections will further improve on the quality and reliability that customers have come to expect from Generac.

Unlike after-market offerings, Generac’s well-proven Bi-Fuel gensets are designed and built with all components specifically engineered to work together – and the units themselves can be easily combined within a MPS configuration. Generac is the single source supplier offering full warranty coverage and service support on the entire system—a huge benefit to users.

The Bi-Fuel units are also the only EPA factory-compliant Bi-Fuel generators available today. Operating within EPA emission standards resulted in a slightly different gas curve for the new engines. Additionally, these new Bi-Fuel generator nodes have a gas curve optimized for standby power generation. Michael Kirchner, Generac’s technical support manager, explains that most generators used in standby applications are typically sized for a peak load of 80%, which is defined by the application’s maximum transient load level. This means that often the typical loading is in the 50% range in actual applications; this is where most of the generator operation occurs. To maximize the benefits of the Bi-Fuel design, the Generac Bi-fuel systems have optimized the natural gas up to 75% within this operating range. Generac Bi-Fuel technology maximizes low-cost natural gas utilization, minimizes the consumption of maintenance- intensive diesel fuel, and extends generator run time.

“Injection timing is critical to NOX and PM levels on a diesel engine, so this creates some constraints as natural gas takes over the load and the electronic control module believes that the engine is operating at lower load levels,” Kirchner explains. “In order to maintain the EPA emission levels, the injection timing and gas levels are optimized in the bi-fuel units at higher loads with the Perkins engine.”