Pre-generate Shadow

I have done shadow using shadow volume technique. Now the question is how do i pre-generate shadows (casting the shadow to textures in my scenery) so that i do not have to calculate shadow all the time. Or is there other efficient ways considering my scene does not changes dynamically?

Use Lightmaps if your scene does not changer, or use SVBSP trees or Beam Trees if you would still like to use stencil volume shadows.