Get 10 of these:

Amazon.com: 4 Mode 1200 Lumen CREE XML T6 Bulb LED Bicycle bike HeadLight Lamp Flashlight Light Headlamp: Sports & Outdoors

Good grief, I can't believe they're $15 now. I have the real magicshine that they copied for this and they're very similar in light output. Put two on your bike for serious run time or serious eye-searing brightness. Heck, I just bought two more.