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 submerged pump assembly at the site is de-energized, and the hoist proceeds to remove and reinstall tubing and the pump assembly. While the electric pump assembly is de-energized, the rig's onboard rechargeable electric power storage system taps into the electric power source normally used for the electric pump assembly. The electric power source of the electric pump assembly recharges the rechargeable electric power storage system while the rig is servicing the well. When the hoist lowers the tubing back down into the wellbore, the energy generated by that operation is recovered and used for replenishing the rig's rechargeable electric power storage system.