Energy systems

Question 1

What are 4 types of energy generation with examples?

Answer 1

1. High temperature heat
   a) Fuels
   b) Geothermal
   c) Solar (concentrated)
2. From solar radiation
   a) PV cells
3. From kinetic energy
   a) Hydro power
   b) Wind
   c) Wave/tidal
   also: mechanic energy from a turbine runs an electricity-producing generator
4. From chemical reactions
   a) Fuel cells

Question 2

What is the efficiency of coal and oil thermal power plants?

Answer 2

40%

Question 3

How does a coal thermal power plant work?

Answer 3

Fuel burned in boiler –> heat transferred to steam boiler –> superheated/high pressure steam spins a turbine –> turbine spins a generator —> generator produces electricity —> condenser turns steam back into water—> cooling water reduces temp of condensed water –> heated cooling water leaves

Question 4

What is the energy conversion in a thermal power plant?

Answer 4

fuel –> heat –> mechanical –> electricity

Question 5

What are some of the energy losses involved in thermal power generation?

Answer 5

-heat
-friction

Question 6

What is the efficiency of nuclear power plants?

Answer 6

30% (lower pressure=lower efficiency)

Question 7

What is the efficiency of a combined heat and power (CHP) plant?

Answer 7

80%

Question 8

How does a CHP plant work?

Answer 8

It generates electricity, and harnesses excess heat for distribution to district heating systems, industrial processes, etc.

Question 9

How does a heat pump work?

Question 10

What percentage of global commercial energy use is derived from fossil source?

Answer 10

80%

Question 11

What are the three major fossil fuel sources?

Answer 11

Coal, oil, and gas

Question 12

What is the global electricity generation percentage for renewables? What energy sources are included in this stat?

Answer 12

13%.

Energy sources: wind, solar, geothermal, wind/wave (not hydro for this one)