Not a whole lot, nevertheless the air being sucked out is not changed with only outside air, but in addition the conditioned air from inside the home. Originates from air leaking to the attic within the supporters, ceiling vents, lights, etc. This method of generating energy straight from solar radiation https://josuelsway.blogsidea.com/41382512/what-does-solar-company-in-sriganganagar-mean