No, you don't need to have candles however they are prefered by many craft practitioners.
If you aren't allowed to use candles, then you could:
Use Fake Candles (These can either be the plastic ones, or the ones that are actually coated/scented with wax. I would suggest the wax candles if you want a more realistic feel but the plastic ones work just as well. These can be found at your local general store/walmart)
Use Virtual Candles (Some websites offer very good virtual candles that you can use, light, and write a description [or spell] for. A website I would recommend would be http://www.gratefulness.org/candles/enter.cfm?l=eng )
Find An Alternative (If you don't have candles at your disposal, perhaps you could use a fireplace or light bulb)
I hope this answers your question, if you need anything else don't hesitate to contact me.