Here's another website that may be helpful for you:
http://www.pyromate.com/Basics-of-Electrical-Firing.htm
That should explain power to you. There are many many different types of electrical firing units, for example the Pyromate systems on the website, Pyrodigital, FireOne... and the list goes on. It is not too difficult to build your own systems as well. I'm not talented enough to do that, but I do know others that have. a simple nail-board is enough to shoot a show.
Once enough power is sent to the match the burst is almost instant. It's faster than the human eye catches, just enough for the bridge wire to heat up and the matchhead to burst.
Where are you from Precision? If you have interest in the fireworks industry you should take the government course and get involved. There's always lots of chances to get on shows all over.