The PowerVR OGLES PC Emulation SDK uses an OpenGL ES on OpenGL wrapper. In other words, if you have installed an OpenGL ICD driver for your GPU and the demos work, it is hardware accelerated.
The most likely reason you’re seeing 100% CPU usage is that you don’t have vsync enabled. Without vsync, the demo just tries to render frames as fast as possible, so it takes up all CPU time (on a single core/single thread CPU). How fast does the demo run?