I doubt I'll be changing my choice of browser on the basis of power consumption.

Been a good thread to dispel the idea that SVG is always the best choice (though it often will be).

If I was making the flag animation for a game I would be using an animated bitmap sequence.

It might be interesting comparing the SVG to an animated gif.

What we are seeing is the performance comparison between rendering in real-time and pre-rendered images/image sequences, the trading of computing power for image size and versatility.