Brilliant Flame
Evocation [Fire, Light]
Level: Clr 1, Drd 1, Sor/Wiz 1
Components: V, S, M/DF
Casting time: 1 standard action
Range: Touch
Effect: One brilliant flame
Duration: 10 min./level
Saving throw: None
Spell resistance: No

This spell calls forth a lick of flame from the caster's hand, sufficient to light a torch, tinder, or other highly flammable substance, but not to do any direct damage. The flame burns with unusual brightness, casting bright light in a 40-foot radius, and dim light for another 40 feet.

Once an object has been set alight by the first lick of flame, the flames can be used to light other objects, just as normal fire could. When the spell duration expires, the flames become natural flames of ordinary brightness.

Arcane material component
A sliver of magnesium.

Ghostfire
Evocation [Fire]
Level: Drd 1, Sor/Wiz 1
Components: V, S, M
Casting time: 1 standard action
Range: Medium (100 ft. + 10 ft./level)
Effect: One ball of flame
Duration: 1 min./level (D) or until discharged
Saving throw: None
Spell resistance: Yes

This spell creates a ball of pale, ghostly flame -- similar to marsh lights, ball lightning, and other such phenomena -- in a colour of the caster's choosing. The caster may concentrate to move the ghostfire at up to 100 feet per round, direct it to remain in place, or have it remain at a fixed distance and position relative to herself as she moves. It sheds light as a torch.

If the ghostfire comes into contact with any creature or object, the spell is discharged and deals 1d6 points of fire damage. The caster may make a ranged touch attack to deliberately strike a target; use the caster's primary casting ability (Intelligence, Wisdom or Charisma) in place of Dexterity for this attack.

Material component
A few scraps of moss.

And by the way, the answer is: Only one, but direct bulb-changing spells suck. Unless you're casting a mass save-or-change spell on a large number of bulbs, you may as well just send the rogue to change it. Buff him first if you have to.