Better insulation in shipping containers plays additional dividends because
of geometric effects. For many smaller shipping containers, the majority of the volume is foam. Shipping costs are often
based on volume rather than weight for these low density packages.
As an example, if one keeps the internal volume of the
container constant, the outer dimension can be dramatically reduced. This reduces the heat loss/gain (which is proportional
to the outside surface area) and hence, the amount of phase change material (dry ice, gel packs, etc.) may be reduced. This
allows further shrinkage of the overall package size. Shown below is a package with a 100 mm cube internal dimension. If it
has 50 mm thick expanded polystyrene, this may be reduced to 5 mm thick vacuum panels. Thus, the total volume is reduced by a
factor of 6 and the volume of insulation is reduced by a factor of 21 as shown below.