As the job intensity increases, in the form of flow rate and pressure, there is a continuous need for increased amount of horsepower for hydraulic fracturing operations. Nevertheless, increasing the number of units at the wellsite to achieve this demand in horsepower is an impractical solution when attempting to reduce carbon footprint. Instead, increasing the power density, energy transfer efficiency, and reducing the amount of parasitic loss offers a superior solution with the introduction of the first natural gas-powered 5,000 HP direct-drive turbine fracturing pumps in North America. A methodology was developed to select this direct-drive turbine technology as the next-generation hydraulic fracturing equipment. The direct-drive pumping unit is equipped with a 5,000 hp continuous duty power end driven by a 5,000 hp dual shaft turbine through a single speed reduction gearbox. This combination provides the most efficient mechanical power transfer efficiency resulting in significant fuel cost savings and reduction in greenhouse gas emissions. In conjunction, a new digital control system has been developed and deployed to enable operational automated functionalities for the pumping unit and backside equipment. This innovative control system provides open interoperable controls, and data analytics for the purpose of eliminating uninformed decisions from pump operators as well as predicting and preventing equipment failures. The objective of this paper is to provide technical details on how digitization enables operational efficiency, equipment reliability, and emission reduction for the direct drive turbine technology.

In today's hydraulic fracturing operations there is an increasing demand for more rate and pressure resulting in more energy intense operations. Therefore, there is a need for more horsepower (HP) to be available on site. In order to support this, along with the industry's transition into a sustainable and low carbon footprint initiative, companies have devoted great efforts in research and development into developing the next generation hydraulic fracturing equipment. As a result, the first natural gas powered 5,000 HP direct drive turbine fracturing pumper has recently been introduced in North America. The objective of this paper is to provide technical insights on how the direct drive gas turbine technology brings a high-power density and efficient energy transfer solution to deliver operational, economic, and environmental benefits. The industry had limited success in utilization of the direct drive gas turbine technology in the past. The main obstacles were unreliable and inefficient turbine to pump power transfer mechanism, low power density, and lack of an integrated engineering approach. The advancements in gas turbines and speed reduction technology, coupled with an in-depth application of equipment design knowledge allowed the company to successfully develop the next generation of hydraulic fracturing technology. The technology is a power train consisting of a 5,000 HP gas turbine engine (5,336 HP actual), a robust single stage reduction gearbox, and a 5,000 HP continuous duty pump. The direct drive turbine technology brings one of the highest power densities and efficient mechanical power transfer designs on the market today. The technology utilizes a split shaft gas turbine to allow for a power gapless powertrain, linear output rpm, and low speed high torque capabilities. A wide variety of fuels can be used including compressed natural gas (CNG), liquefied natural gas (LNG), field gas, and liquid fuel (e.g., diesel). Based on certified third-party emissions data, the direct drive technology is shown to have one of the lowest greenhouse gases (GHG) and Environmental Protection Agnecy (EPA) regulated emissions profiles. At the time of this writing, the first direct drive turbine frac fleet has been deployed in the Haynesville for 2 years and more recently introduced in Canada (Montney and Duvernay).

Recently, the North America Oil and Gas industry has seen a rapid increase in the adoption of new hydraulic fracturing technologies such as dual-fuel diesel engine, electric system powered by gas turbine or engine on-site and turbine direct drive technology, to reduce emissions and operating costs. The objective of this paper is to provide a detailed analysis of economic, environmental, and technical considerations when selecting the next generation hydraulic fracturing equipment platform. It is believed that any next-generation technology must meet the following key requirements: 1. Reduction of GHG and EPA regulated emissions; 2. Reduced equipment footprint; 3. Capable of meeting the most stringent noise standard; 4. Improved reliability; 5. Improved pad-to-pad mobility; 6. Reduced maintenance and personnel costs; 7. Competitive capital cost. For the selection process, a methodology was developed to evaluate the energy density of fuel, thermal efficiency of prime movers, mechanical power transfer efficiency, and equipment operating environment and configuration against the above objectives. The methodology also considered the technical and commercial feasibility of key components. Natural gas is selected as the mobile primary energy source due to its higher energy density and lower emission profile than conventional diesel, and more economical and widely available on-site. Among all available natural gas-powered engines evaluated, which included dual-fuel diesel engine, gas reciprocating engine, single large turbine and direct drive turbine, the direct drive turbine scored the highest. The direct drive pumping unit is equipped with a 5,000 HHP continuous duty power end driven by a 5,000 HHP dual shaft turbine through a single speed reduction gearbox. This combination provides the most efficient mechanical power transfer efficiency resulting in significant fuel cost savings and reduction in greenhouse gas emissions. Because of its high-power density, the direct drive turbine system can potentially reduce the number of on-site equipment by 43% and personnel by 31%. Comparing to other next generation hydraulic fracturing system, the direct drive turbine technology has the lowest capital cost per HHP.