Ensign, a global leader in drilling and servicing wells, is celebrating the next generation of hybrid land rigs with Rig 162, featuring the Cat® Land Drilling Energy Storage System.

“The rig is unique, the only one in the world like it,” says Don Molen, senior drilling manager for Ensign in the Rockies. “It was developed in collaboration with Caterpillar and is a first-of-its-kind hybrid powered by natural gas generators and a unique battery storage system that consists of a Cat lithium battery pack and an integrated energy control system.”

Solely natural-gas-powered generators aren’t known for their response to transient loads. As different rig operations demand varying energy, the power systems in place must respond quickly to an increase in demand. The Cat Land Drilling Energy Storage System solves this problem for Rig 162 by allowing the battery and generators to work in tandem. The battery is quick to pick up an energy load while the generators ramp up. When the generators are ready, the Energy Storage System ramps down and the rig experiences a smooth power transfer.

“The system performed extremely well, exceeding expectations,” says Rigo Canessa, senior controls engineer for Ensign. “With the Energy Storage System’s ability to mitigate transient load demands and a host of other features, the entire system performed better than adding an equivalent-sized generator to the rig.”

Ensign is also experiencing less engine wear, the elimination of power blackouts and a significant reduction in emissions on Rig 162, which is currently working in Wyoming. Compared with a comparable diesel-powered rig, it delivers between 15-25% less CO₂, an 80% reduction in NOx and a 90% reduction in particulate matter emissions. The rig also experiences better energy transfer and over time will be able to predict the power needs for specific operations.

“Depending on the operation, the generators can be put into standby mode or even turned off completely,” Molen says. “With this efficient energy management, the rig operates with a 20% improvement in fuel consumption.”

Energy quality and superior engine management will also combine to decrease engine wear and maintenance requirements going forward.

Ensign’s leadership in the natural gas-powered rig space dates back to the early 2000s, when the company ran the largest fleet of natural gas land rigs. In 2014, Ensign’s first land-based hybrid rig drilled a commercial well. The Cat Land Drilling Energy Storage System on Rig 162 is a design upgrade on that initial model and a reflection of Ensign’s drive for continuous improvement. It shows the company’s continuing commitment to this technology and is a natural progression with great potential.

“It certainly is promising,” Molen says. “The rig’s performance so far has been exceptional, and we are optimistic about the future of this technology.”