Shadows... dynamic light... well, it's a hard subject.
Canvas plugin did have a high performance influence last time I used it (for the exact same reason as you did). I don't know of any workaround that could help with this right now. I did some research and tries with the illuminated.js script, but didn't manage to make a plugin out of it.
But, in your first post, you asked for static lights like a lamp. This particular case is quite simple and doesn't require canvas at all.
Here is an example on how to do a simple static light.
Edit : highlight on the method :
- a layer "lights", black, not transparent, on top of the game.
- add a multiply effect to this layer
- add white sprites (or colored ones if you want red, green and other lights) in this layer
The multiply will make everything black in your game, except what is lighten.