Global Sustainability Exam 2

Wind is continuously regenerated in the atmosphere as the solar radiation is converted into kinetic energy

True

Wind power available at any location does NOT depend on the topographical features of that location

False— it DOES depend on the….

What is the name of the principle by which wind power is used to generate electricity?

ELECTROMAGNETIC INDUCTION 

What are the two types are wind TURBINES?

Horizontal axis wind turbine and Vertical axis 

Conduction Loss:

Loss in electric voltage, It is directly proportional to: 1. Length of the conductor and 2. Cross sectional area of conducting wire.

Step up and down transformers:

The machine that enables raising electrical voltage is called a STEP UP TRANSFORMER.

this voltage needs to be lowered so it can be used practically. Which is done by using a STEP DOWN TRANSFORMER.

Which form of renewable energy is the most expensive?

Solar

How much does power cost when generated by Solar power?

Concentrated. PV 18-19 cents

Biggest advantage to wind power?

We can’t ever get rid of wind because then we would have no atmosphere 

In most cases, wind velocity must be greater than ____ miles per hour to be usable

7

What is the efficiency of horizontal axis wind Turbines?

80%

What is the mass of the sun?

2.2* 10^27 tons

Majority of solar energy is not incident on earth due to diametrical differences between the sun ad the earth

TRUE

Solar energy DOES arrive at a constant intensity during the day

False— it DOES NOT arrive at a constant….

Who invented the first solar power steam engine?

AUGUSTE MOUCHOUT 

What was the first silicon solar cell made out of?

A semi-conductor

The sun procedures its heat and energy using ______

Nuclear Fusion

CSP stands for?

concentrating solar power

What does CSP do?

CSP focuses the sun’s energy to boil water which turns to steam which is then used to provide power

What zone of the earth receives the most sun?

The tropics 

Solar power is made out of what types materials?

Semiconductor (example would be silicon)

What is the atomic number of silicon?

14 (this number means the number of proton)

Silicon atom has what type of charge?

No charge/ 0 charge

Semiconductors in their natural state can conduct electricity.

FALSE, they can be MADE to conduct, not naturally 

What is the process by which silicon atom is converted into an ion?

Process of DOPING

N type silicon is chemically stable true or false 

false- too many electrons

P type silicon is chemically stable true or false

False— not enough electrons

What is electricity?

The flow of electrons

What is biomass?

any organic material except coal, oil, natural gas. Etc. that is used for energy generation 

Is Biomass a renewable energy source?

YES

Types of biomass…

Wood fuel, rubbish, alcohol fuel, crops, landfill gas

Applications for Biomass

• Industrial process heat generation 

• Electricity generation 

• Generation of heat and power for industrial, residential and agricultural purposes 

• Production of liquid fuels for vehicles 

• 77% of the energy produced by biomass sources is used by the industrial sector 

• Biomass accounts for 14% of the world's energy needs

Biofuels

conversion of biomass into liquid fuels for transportation 

Biopower

conversion of biomass into gaseous fuel or oil to generate electricity

Bioproducts

conversion of biomass into chemicals for making products that are made from petroleum

Combustion

burning biomass in a stove, furnace or boiler

Gasification

conversion of biomass into a gaseous fuel composed of H2 and CO that retains most of its heating value

Pyrolysis

thermal decomposition of biomass to produce a combination of solid, liquid, gas products that are combustible

Fermentation

conversion of biomass (carbohydrates) through distillation into ethanol (C2H5OH) for blending with gasoline for motor vehicle use

Anaerobic Digestion

Conversion of biomass into a gaseous mixture of CO2 and CH4 (methane)

Two most important advantages for Biomass are….

Biomass sources are inexpensive and widely available, and Biomes sources do not contribute to a net increase in CO2

What does Tidal Power mean?

 is a means of electricity generation achieved by capturing the energy constrained in moving water mass due to tides

Cold air is more dense than hot air

TRUE

E= xMg (equation for potential energy)

x is the height of the tide, M is the mass of water, and g is the acceleration due to gravity

a tidal energy generator must be placed in a location with very low-amplitude tides 

FALSE- must be HIGH-amplitude tides

Tidal energy has an efficiency of ___ in converting the potential energy of the water into electricity

80%

What are two environmental effects of tidal power?

Requires no fuel, and produces No emissions