Reducing Energy Loss

Energy loss meaning

Energy wasted to unwanted stores, usually thermal

Insulation purpose

Reduces heat transfer by conduction, convection and radiation

Loft insulation

Fibreglass traps air → reduces conduction and convection

Cavity wall insulation

Foam reduces conduction; trapped air reduces convection

Double glazing

Air gap reduces conduction and convection

Draught excluders

Reduce convection by stopping warm air escaping

Carpets

Reduce heat loss through floor by conduction

Curtains

Reduce heat loss through windows by convection and radiation

Shiny surfaces

Reduce heat loss by reflecting infrared radiation

Lubrication

Reduces friction → less energy lost as heat

Streamlining

Reduces air resistance → less energy wasted

Thermal conductivity meaning

How well a material conducts heat

Low thermal conductivity

Good insulator

High thermal conductivity

Good conductor

Thicker insulation

Reduces heat loss more effectively

Payback time meaning

Time taken to recover installation cost through energy savings

Payback time formula

Cost of installation ÷ annual savings

Short payback time

More cost‑effective

Reducing energy loss in homes

Insulation, double glazing, draught proofing

Key idea

Reducing heat transfer improves efficiency and saves energy