Rather than ironing you could put shirts (or other clothes) in a dryer with an ice cube, set to medium and run for 15 minutes. The ice cube will turn to steam which helps remove wrinkles. Hang the shirts up immediately after removing them from the dryer so that the wrinkles don’t come back.
Sacrilege we hear you say, the clothes dryer is very expensive to run. Or is it?
If you took 5 minutes to iron a badly crumpled, dry shirt it would cost about 1.9p. At that rate 5 shirts a week for a year would cost £4.94 (=16.5kg CO₂). Not much we hear you say, but that is just your shirts!
Buy the lowest wattage iron you can find especially one that does not have steam (use a water spray, wet tea cloth or damp clothes instead for the steam-ironed effect). A 1,000W iron will save you 8p per hour compared to a 1600W iron.
The automatic safety shut off feature cools down the iron’s plate completely when not in use for a certain amount of time.
Check that the water reservoir of a steam iron is easy to fill and the iron has a few steam vents.
Check how long the iron take to warm up and how long does it take to re-heat? The quicker the better.
Does it have variable heat/fabric settings, from delicate fabrics to cotton/wool?
Does it have a self-clean feature? Some types of clothes iron use a burst of steam to clear the holes in the sole plate.