Patent attributes
A mobile service rig includes an onboard rechargeable electric power storage system (e.g., a battery, supercapacitor, etc.) for powering the rig's hoist and drive wheels. Under battery power, the rig travels overland to service wellbores at various wellsites. Once at a wellsite, a pumpjack at the site is de-energized, and the hoist proceeds to remove and reinstall wellstrings (e.g., tubing and sucker rods). While the pumpjack is de-energized, the rig's onboard rechargeable electric power storage system taps into the electric power source normally used for the pumpjack. The drive wheels and hoist can drain the rig's rechargeable electric power storage system, but the pumpjack's electric power source can gradually recharge it while the rig is servicing the wellbore.