Power Connect Newsletter

Goodbye 2018; hello 2019. As we start a new calendar year, there are developing trends we are seeing when it comes to purchasing generators.

The market is rapidly changing due to an increase in environmental concerns and regulations. More stringent emission regulations are being placed on diesel engines. The U.S. Environmental Protection Agency (EPA) is driving cleaner standards by emphasizing the use of fuels like low sulfur and ultra-low sulfur diesel fuel to improve engine efficiency. The change in emissions standards could boost diesel prices by 20 – 30%, according to the International Energy Agency (IEA). The IEA and the Department of Energy expect companies to switch to natural gas when they can, as pricing looks to remain flat. 

Gas generators are more environmentally friendly, they comply with all emissions standards and emit less amounts of pollutants compared to diesel generators. Factoring in the difference in engine efficiencies, diesel generators have more than twice the fuel operating cost of a natural gas generator. The more hours you operate the generator on a yearly basis, the more you will save on fuel costs with the natural gas unit. 

That leads to our next trend: the growing popularity of gas generators. Along with the rising cost of diesel fuel, diesel generators also require more maintenance. Several end-users are switching to natural gas fuel to avoid the hassles that come with maintaining diesel fuel. It requires annual testing and periodic maintenance to remove contaminants and avoid bacterial growth. It is also significantly affected by limitations on fuel delivery that occur during and following major storm events. 

Natural gas units can theoretically run for an unlimited amount of time, as the national pipeline network represents an uninterruptible supply. Diesel generator running times are limited to the amount of fuel stored in the on-site fuel tank, which is typically sized for 24 to 72 hours. If an outage runs longer, the generator’s reliability is limited by your ability to refuel, which is a significant challenge during major weather events. 

In practice, both natural gas and diesel standby generators require maintenance, so there are routine interruptions for oil and filter changes, etc.

The third and final trend for 2019 is the rise of bi-fuel. Bi-fuel generators simultaneously burn both diesel and natural gas, effectively capitalizing on the benefits of both diesel fuel and gaseous fuel. A bi-fuel engine is a compression-ignited engine modified for simultaneous combustion of both diesel fuel and natural gas. Diesel fuel, which ignites at 500° - 750° F (260° - 399° C), is injected into the combustion chamber as a pilot fuel. The ignition of the diesel fuel in turn ignites the natural gas, which has a much higher ignition temperature of 1150° - 1200° F (621° - 649° C). 

Bi-fuel generators start up using 100% diesel fuel. After certain criteria are met – such as acceptance of the electrical load – the generator’s controller introduces natural gas to the fuel mixture. The controller slowly reduces diesel fuel injection while adding natural gas, until the unit is running more on natural gas than on diesel. Under typical conditions, bi-fuel generators will operate on a ratio of 25% diesel to 75% natural gas, with no reduction in power. Run times are extended while on-site fuel storage requirements are decreased. This is because natural gas, not diesel, is the predominant fuel in a bi-fuel system.

When choosing a backup power solution, working with a local generator representative is an important step in ensuring the ideal products are specified to meet city, state and national codes as well as the needs of the customer. For local support, visit our Generac Industrial Power Distributor locator or call us at 1-844-ASK-GNRC or email ASKGNRC@generac.com to talk to a Generac technical sales representative.