IMPROVING FRACKING POWER & EFFICIENCY
Rolls-Royce Power Solutions’ MTU hybrid e-frac system features a modular design. Users can customize the system with any
combination of the company’s battery storage systems and natural gas generators to suit the specific power needs of a frac
operation. The battery systems also feature a proprietary microgrid controller, which automates the coordination of energy
storage and demand between the battery system and the generators.
the savings really comes from is on the consumable in the fluid
end. I’m getting 37% more work out of the 11-in. stroke than I am
out of the 8-in. stroke.”
During validation testing in 2019, the pump was subjected to a 2
million cycle endurance test at a 250,000-lb rod load for the entire
test. After 450 hours of testing, the pump exhibited no cracks in
the frame, no bearing failures and minimal damage to the cross-
heads and general bearings. The pump is now commercially
deployed in several basins across North America.
Hybrid e-frac systems
Rolls-Royce Power Solutions, through its MTU brand of power
systems, launched its hybrid electric fracturing (e-frac) power
solution in 2021. It integrates a natural gas reciprocating engine
with a battery energy storage system. Compared with a conven-
tional turbine e-frac setup, this hybrid system can tailor opera-
tional needs based on the load requirements of a specific opera-
tion, allowing power to be utilized more efficiently.
The system was also designed to be modular. Users can cus-
tomize the system to generate as much, or as little, power as they
32 need. Any combination of MTU’s EnergyPack battery storage
systems – which range in capacities from 70 kWh to 2,200 kWh –
and natural gas generator set can be mixed and matched.
Last year, Rolls-Royce used simulation software to highlight
the potential energy efficiencies possible with its hybrid e-frac
setup versus a turbine e-frac setup. The company simulated a
frac operation using a turbine setup with a baseline load of 18-20
Megawatts electric (MWe) and a peak demand of 20-21 MWe. It
then simulated the same operation with a hybrid system using
10 2.5-MWe gas gensets and two 2-MWe battery energy storage
systems. The conventional e-frac setup with one gas turbine generator
was only able to run between 50% and 65% load capacity during
the simulated operation. On the other hand, the hybrid e-frac sys-
tem was able to run at 80% capacity without needing to use all 10
gensets – eight gensets ran throughout the simulation while two
served as backups.
One of the keys to this increase in load capacity was the com-
pany’s proprietary microgrid controller, which is installed in the
battery energy storage system. Microgrids are small-scale local
M A R C H/A P R I L 202 2 • D R I L L I N G C O N T R AC T O R
IMPROVING FRACKING POWER & EFFICIENCY
Above: To improve system durability, Liberty’s digiFrac elec-
tric pump features a power frame with a curved internal ge-
ometry that the company believes will improve laminar flow
and reduce the risk of cavitation.
Right: Liberty plans to commercially launch its digiFrac sys-
tem later this year. The company believes the new technol-
ogy can produce twice as much horsepower per unit as a
conventional pressure pump, even as its multimotor design
allows each motor to run at a lower horsepower.
power networks in which various energy sources and storage
systems are managed automatically through a master controller.
The MTU microgrid automates the coordination of energy stor-
age and demand between the battery system and the generators
in the hybrid e-frac system, turning them on and off as needed to
optimize fuel efficiency and emissions.
“Getting the engine to its optimal range is pretty simple with
the energy storage. We’re able to move the engine up to a more
efficient load management situation – when you’re going from
50% to 80%, you’re generating more work per gallon of fuel from
that engine,” Mr Woodruff said.
He called the microgrid/EnergyPack combination a “whole new
technology platform” in the e-frac space. Beyond the batteries, an
EnergyPack houses an electronic control unit, transformers and
cooling equipment, making it a self-contained energy storage
unit. By connecting its control system to the MTU microgrid,
users can ensure a continuous and efficient distribution of power
throughout a frac run.
“The automation feature helps us optimize fuel consumption,
and that has other benefits when it comes to emissions and asset
utilization,” Mr Woodruff said. “We’re creating a system where
Click here to watch a video interview
with Scott Woodruff about Rolls-Royce
Power Solutions’ MTU e-frac.
D R I L L I N G C O N T R AC T O R • M A R C H/A P R I L 202 2
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