An energy storage apparatus for storing energy transmitted by a power transmission line includes an elastically deformable component and an actuator-generator. The metal-containing transaction cards may be standard-sized or any other size yet still usable as a transaction card. The flap loosens and removes residual snow, as well as other debris, left by the snowplow. The device includes a resistive switch having a first terminal connected to the peaking path and a second terminal connected to a voltage reference, and a controller configured to set the resistive switch to a first resistance value when a power input of the Doherty amplifier is below a threshold and to a second resistance value when the power input of the Doherty amplifier is above the threshold.