You could live with batteries for the distortion pedals, but I would recommend having a power adapter for time-based pedals such as delay, chorus etc. Those suck up a lot of power. If you plan to invest in more pedals, getting a good adapter might be a good idea, you can always make your own power adapter splitter so that you can use that adapter to power up more than 1 pedal. But do make sure that your total current drawn doesn't exceed the rated amount.