Double glazing reduces energy loss.
the gap between the two pieces of
glass is filled with a gas or contains
a vacuum
Lost insulation reduces
energy loss by conduction
and convection; warm air in
the home rises,energy is
transferred through the ceiling
by conduction
Cavity wall insulation reduces energy
loss by conduction and convection the
air in the foam is a good insulator and
the air cannot move by convection
because it is trapped in the foam
Energy efficiency
Efficiency = useful energy output(x 100%) DIVIDED by
total energy input
Energy transformations can be shown by sankey diagrams
Energy from the source(home) is lost to the
sink(environment)
Different types of insulation cost
different amounts and save
different amounts of energy
Payback time = cost of insulation DIVIDED by
annual saving