1.9 Heating And Insulating Buildings

Question 1

Name 5 things that can be fitted in homes to minimise the rate of energy transfer out of their homes

Answer 1

• fibreglass loft insulation (contains air gaps so reduces conduction)
• cavity wall insulation (traps air in small pockets to reduce energy transfer by convection)
• double glazing (to reduce energy transfer by conduction through windows)
• draught proofing (to reduce convection)
• aluminium fool behind radiators (to reflect infrared radiation back into the room)

Question 2

Why is fibreglass a good insulator?

Answer 2

It contains trapped air

Question 3

What is the u value of a substance?

Answer 3

Joules per second that travel through a metre squared of the substance

Watts/metre2

Question 4

What is the relationship between the u value of a substance and how good of an insulator it is?

Answer 4

The lower the u value, the better the material is as an insulator because it means it is transferring less energy per second per metre squared

Question 5

How do solar heating panels work?

Answer 5

They contain water that is heated directly from the Suns radiation, which can be used to heat buildings or provide hot water

Question 6

Why are solar panels cheap to run?

Answer 6

They don’t use fuel

Question 7

What do most people want to do in order to reduce their fuel bills?

Answer 7

Minimise the rate of energy transfer out of their homes