Leading oil and gas operators are increasingly turning to self-generation of field power to achieve multiple and sometimes competing objectives:  maximizing uptime, reducing emissions, mitigating flaring, and keeping their asset development plans on track.

As operators move into regions not readily served by the utility grid, self-generation may be the only option. However, once you move down the self-generation path, your choices boil down to traditional reciprocating engines or small gas turbines (sometimes called microturbines).

The need for reliable energy and clean emissions is also driving the trend of oilfield electrification, as operators look to maximize power capacity without exceeding stringent emissions thresholds requiring expensive and time-consuming air permits.

A popular option for many upstream and midstream operators is Caterpillar reciprocating generator sets. In this article, we compare and contrast the differences between Caterpillar reciprocating gas engines and small gas turbine powered gensets from FlexEnergy Solutions.

READ MORE: FlexEnergy Solutions: Q&A on Gas Turbines for Oilfield Electrification

Self-Generation Power Applications

In general, we find operators turn to self-generation for three main applications, including power for individual well sites, a grouping of sites (through their own microgrid) , or at centralized facilities in both the upstream and midstream sectors.

Self-generation in the oil and gas sector is often used to power:

• Individual well sites
• Large production pads
• Centralized production facilities (tank batteries)
• Produced water disposal facilities (SWD)
• Microgrids serving multiple well sites/pads
• Gas lift operations
• Natural gas midstream facilities.

FlexEnergy Solutions Gas Turbines Vs. Caterpillar Reciprocating Engines

Self-generation in oil and gas for oilfield electrification is dominated by two major options: generators powered by reciprocating engines or small gas turbines and microturbines.

Caterpillar Reciprocating Generator Sets. Caterpillar’s traditional reciprocating engines, available in both natural gas and diesel configurations, are well-suited for self-generation applications. These engines have a long-standing reputation for reliability in the oilfield, where they are widely used in compression, land production generator sets, and land drilling engines. Their durability, coupled with the extensive availability of spare parts and replacement engines, ensures minimal downtime in case of faults. However, as reciprocating engines, they are subject to the typical limitations of this design.

Pros:

• This old technology is well understood.
• Wide availability.
• Diesel and natural gas-fueled options available.
• Generally higher electrical efficiency than most turbines.

Cons:

• Many moving parts and frequent maintenance requirements generally translate into lower uptime and reliability or the need for redundancy. 
• Higher emissions relative to alternatives (turbines).
• May require secondary emission treatment solutions (e.g. SCR/Selective catalytic reduction) that can be costly and maintenance intensive.
• Diesel can be expensive and inconvenient (for diesel-powered options).
• Can suffer from knock (autoignition) issues on high btu gases.

READ MORE: Turbines vs. Reciprocating Engines: A Matter of Reliability

Small Gas Turbines and Microturbines. Natural gas turbines from FlexEnergy Solutions have been in common use for decades and are finding greater adoption in the oil and gas industry for self-generation options.

Pros:

• Proven technology used worldwide in a variety of applications.
• Few moving parts means very high reliability and high uptime.
• Very low emissions when compared to reciprocating engines.
• Natural gas-fueled, providing beneficial use of tank vapors and waste gas streams.
• Due to the significantly higher fuel gas tolerance (325 Btu/ft3 to 1,900 Btu/ft3), turbines can operate on a wide range of untreated fuels and, as a result, are ideal in mitigating flaring by converting waste gas into clean power.

Cons:

• Not as widely available as Caterpillar reciprocating engine gensets.
• Initial startup costs can be higher than reciprocating engine gensets, depending on the application and configuration.
• Can be susceptible to derate, based on installed altitude and high ambient temperature.

READ MORE: Microturbines vs. Reciprocating Engines for Oil & Gas Power Generation

FlexEnergy Solutions Vs. Caterpillar Reciprocating Engine Gensets

Small gas turbines and microturbine powered gensets from FlexEnergy Solutions deliver several advantages over those using reciprocating engines from Caterpillar engines (and other reciprocating engines), including:

Improved Reliability (Uptime). The high reliability and few moving parts contribute to the highest uptime and reliability of the Flex Turbine microturbine and GT2000S, especially when compared to reciprocating engine generators, safeguarding continuous production and cash flow. The Flex Turbine requires only one eight-hour scheduled maintenance annually, typically completed in one shift. As a result, FlexEnergy Solutions turbines boast a 99.5% uptime track record.

Lowest Emissions Option (Better Than The Utility). The Flex Turbine is usually cleaner than most grid power options. Compared to nearly every utility power grid, FlexEnergy Solutions delivers the lowest emissions performance. In most cases, FlexEnergy Solutions offers the lowest emissions of any self-generation option.

READ MORE: Clearing the Air On Oilfield Electrification

READ MORE: Understanding Field Power Emissions Profiles and Options

Put More Power for Less Emissions on a Single Site. A lower emissions footprint means you can put more power on a single site while staying below emissions thresholds and avoid expensive and operationally restrictive Title V Operating permits. In a Case Study, independent tests confirmed that emissions of NOx (an ozone precursor), carbon monoxide, and NMNEHC at a facility powered by FlexEnergy Solutions’ GT2000S turbine generators were 15, 6, and 8 times lower than their respective permit requirements.

CASE STUDY: Decarbonizing Oil & Gas Production with Oilfield Electrification

Diesel Displacement. Using flare and vent gas produced on-site as fuel eliminates the emissions associated with transporting diesel to the facilities and provides a lower emissions power option than diesel- or natural gas-powered reciprocating engines.

Fast Service Response (We Are The OEM). Unlike many other self-generation providers you do not need to deal with a local distributor or an agent, we are the Original Equipment Manufacturer. If you have an unexpected issue, there is no middleman; you will talk directly to the people who design, build, and maintain our turbines. That provides faster service response, efficient troubleshooting, and high reliability.

Contact Us Today

Contact FlexEnergy Solutions to learn more about our clean, dispatchable, and reliable field power solutions at sales@flexenergy.com or +1 (720) 826-0708.