If you need to plane a lot of plank you're doing yourself a favour by using an electric planer. It runs on a cord, which means you always have a steady and constant energy supply.
From Amazon
Bosch Professional GHO 40-82 C planer (850 W, including rebating depth guide, parallel guide, dust bag, auxiliary blade, in carrying case)
Conrad Electronic
Bosch Professional GHO 40-82 C Power planer incl. case Plane width: 82 mm 850 W Fold depth (max.): 24 mm
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