Sure, you can plane by hand, but it's easier and faster with an electric planer. You will need access to an electrical outlet, but mains-powered tools have a very stable power subbly.
From Data Powertools
Makita 2012NB/2 Portable Planer Thicknesser 240V
B&Q
Makita 1650W 240V Corded Planer 2012Nb/2 - One Size