Question

choose the right answer:

a) What is most energy-efficient, a regular refrigerator standing in a fully insulated room, or a fully insulated refrigerator standing in a regular room?
1 - completely isolated in a common room
2 - common in a fully isolated room

b) Is a heat pump most efficient at large or small temperature differences?
1 small
2 large

c) Water is a good energy carrier and therefore fits in ordinary air heat pumps for villas.
1-true
2- false

d) By replacing the expansion valve in a heat pump circuit with a turbine, a substantial amount of electricity can be produced.
1-true
2- false

Answer 1

Answer:

a) What is most energy-efficient, a regular refrigerator standing in a fully insulated room, or a fully insulated refrigerator standing in a regular room?

Correct answer is (1) - completely isolated in a common room

b) Is a heat pump most efficient at large or small temperature differences?

Answer is (1) small

Efficiency of heat pump = TH/(TH - TL)

If the temperature difference is small then the efficiency is large.

c) Water is a good energy carrier and therefore fits in ordinary air heat pumps for villas.

Answer is (1) True

d) By replacing the expansion valve in a heat pump circuit with a turbine, a substantial amount of electricity can be produced.

Answer is (2) False