Unit 10- Energy

Question 1

Primary Energy

Answer 1

• Energy resources that have not been converted or transformed
• Initial energy resource- energy contained I raw fuels
• i.e coal, oil, natural gas, hydro power, biomass, solar energy, wind energy
Supply management- finding new energy sources

Question 2

Secondary Energy:

Answer 2

• Energy transformed from conversion of primary energy
• End use energy- energy that is actually used to do work
• i.e. electricity generated from coal, oil, nuclear, or wind to power a light bulb
• For management purposes, usually classified by sector (industrial, commercial, residential, transportation)
Demand management- individual usage of cars, or mass transit by public transport

Question 3

Energy Efficiency:

Answer 3

• Difference between primary (extracted) and secondary (utilized) energy
• Efficiency requires reducing the this difference
• Analogous to reducing the difference between water withdrawal and water consumption to increase efficiency
More than half of the energy we consume does not provide us with useful services such as heat, light, and mobility (more than half is wasted)

Question 4

Cogeneration

Answer 4

○ Excess heat produced during generation of electricity is captured and used to heat workplaces and homes
Can double the efficiency of a power plant

Question 5

Coal gasification/combined cycle generation

Answer 5

○ Coal is treated to create hot gases that turn a gas turbine
Hot exhaust of this turbine heats water to drive a conventional steam turbine