UV light is critical for bearded dragons. They will die without it and it's recommended to use heat lamps rather than just pads because some will burrow [especially females trying to lay eggs, and ones that are just crazy... like mine] into the sand and beardie's can't feel belly heat so they will just let their bellies burn. For the same reasons, heat rocks are pretty much forbidden. But heat rocks just way overheat.
Are you thinking about getting a beardie or just curious about setups?
Edit: also beardies need lots of running space but also love to bask up high, so they'd need a big tub. Or just a tank. Lots of people do custom enclosures.