Trying to add a 240V circuit to the breaker box -- is there space?
Read my answer here that talks at length about what "spaces" are and how duplex breakers work.  

It appears that you have one space left.  Any 2-pole (240V) breaker needs to sit in 2 spaces so something special will have to be done.  The article I linked should give you plenty of ideas, e.g. using a duplex breaker for two 120V circuits to free up a space.  

If you expect to add any more circuits in the future, you may be better off just adding a sub-panel. 

Lastly while you're in the panel you might look at a few minor problems.  First, some of the white wires going into breakers are not neutrals.  They should be taped or marked at both ends to indicate they are not actually neutrals.  Second, it looks like too much bare wire is exposed on most of the wires going into the breakers, probably too much insulation was stripped (there's a "how much to strip" guide printed or embossed on the breaker.)  It can be easily trimmed back.