Patent ID: 8127833
Filing Date: 2012-03-06
Classification: E21B

Abstract:
1. An apparatus, comprising: a downhole oilfield system, the downhole oilfield system comprising: a conveyance; a downhole tool attached to the conveyance, the downhole tool comprising; a work performing module; a potential energy harvesting device configured to convert and store potential energy as a result of lowering or raising the downhole tool in a well; and wherein the potential energy harvesting device comprises a first plurality of rotation inducing angled wheels and a second plurality of rotation inducing angled wheels oriented in opposing directions configured to contact and roll along a well wall; the first and second plurality of rotation inducing angled wheels imparting an opposing rotation spin to regions of the energy harvesting device; and an energy storage module operatively connected to the regions of opposing rotation and harvesting energy from the relative rotation between the regions of opposing rotation.