Oops my bad, was thinking of different bulbs (active UV t-rex bulbs).
Are you sure it is only 22 watts? I don't think it is possible for a light that size to be of such low wattage, even the very small UVA bulbs dont have a lower wattage than 40.
Powersun bulbs give off both UVA/UVB rays, and are about that size. They are suitable for large enclosures.