Video to accompany
Bake Normal Maps with Blender Cycles (http://www.katsbits.com/tutorials/blender/cycles-bake-normal-maps.php). Keeping the process as simple and uncomplicated as possible the basic procedure used to generate a Normal map using Cycles Render texture bake feature is shown. Essentially so long as the low-resolution mesh has a UV map and image assigned (real or virtual), it's possible to Bake various types of texture map, including Normals.
For more in-depth discussion about the pros and cons using Cycles Bake
read the tutorial (http://www.katsbits.com/tutorials/blender/cycles-bake-normal-maps.php) or
purchase the eBook in Store (http://www.katsbits.com/store/index.php?act=viewProd&productId=47).