EARTHSCI - Energy Resources

energy

the capacity to do work

Resource

any item which is used for a specific purpose

Renewable Resources

-natural resources that can be replenished in a human time scale

-Solar, Geothermal, Wind, Biomass, Water

Nonrenewable Resources

-natural resources that can be replenished in a human time scale

-nuclear and fossil fuels

I. FOSSIL FUELS

a. coal

b. petroleum

c. natural gas

II. NUCLEAR ENERGY

NONRENEWABLE RESOURCES:

FOSSIL FUELS

The world's primary energy source.

COAL

-A black combustible rock made up of elemental carbon, hydrogen, oxygen, nitrogen, and varying amounts of sulfur.

-Formed from the remains of plants that once grew in swamps and adjacent forests millions of years ago.

PEAT

-forms from continuous burial and compaction of decaying vegetation

-a precursor of coal containing 50% carbon.

-transformed into coal at burial depths of 4 to 10 km.

Lignite

Bituminous coal

Anthracite

CLASSIFICATIONS OF COAL

(ACCORDING TO CARBON CONTENT):

Lignite

classification of coal:

- a soft, dark-brown, low rank coal composed of 70% carbon.

Bituminous coal

classification of coal:

- dull, black, mid-rank coal composed of 70% carbon

Anthracite

classification of coal:

- shiny, black, high-rank coal composed of 95% carbon

-from giant plants that died in swamps and buried under water and dirt. heat and pressure turned them into coal.

How is coal made?

PETROLEUM

-comes from the Latin words petra which means "rock", and oleum which means "oil".

-naturally occurring liquid composed of complex hydrocarbons

With increasing pressure and temperature due to continuous burial, the organic matter in aquatic organisms transforms into a waxy material known as kerogen, and eventually into hydrocarbons through the process of catagenesis.

HOW PETROLEUM IS MADE?

Natural gas

a hydrocarbon mostly made up of methane

Methane is a simple chemical compound that is made up of carbon and hydrogen atoms.

This gas is lighter than air and highly flammable.

Form within a specific depth, pressure, and temperature range known as "oil window"

If the temperature increases beyond oil window, oil is converted into natural gas in a process called thermal cracking

How is natural gas made?

NUCLEAR ENERGY

Nuclear reactions occur when atoms of one species of a chemical element are transformed into atoms of another species by nuclear change.

fission

splitting of heavy atoms into lighter atoms.

fusion

combination of two light atoms to form a heavier atom.

1. Fuel rod should maintain a certain temperature; otherwise, it could be generate temperature high enough to use meltdown or explosion of radioactive materials.

2. The generation of radioactive wastes.

TWO PROBLEMS ASSOCIATED WITH NUCLEAR POWER PLANT:

1. geothermal energy

2. hydroelectric energy

3. wind energy

4. solar energy

5. biomass

RENEWABLE

RESOURCES

GEOTHERMAL ENERGY

Earth's internal heat

- In cold areas like Iceland, geothermal heat is used directly.

- Water heated by hot volcanic rocks is used for heating household interiors, growing vegetables during winter, aquaculture, and heating humanmade pool.

- In ancient times, Romans recognized the importance of hot spring for heating and for treating skin diseases.

SEVERAL WAYS OF HARNESSING GEOTHERMAL ENERGY

HYDROELECTRIC ENERGY

- Water and gravity generate energy

- An object at rest in a higher elevation has a gravitation potential energy. When it moves to lower elevation, potential energy is transformed into kinetic energy

Hydropower

the power generated by the energy from falling water or fast running water.

Hydroelectricity

electricity generated from hydropower.

Head- height difference between source and the water's outflow

Water enters the intake at the bottom of the reservoir and flows through a tunnel or large pipe called penstock to reach the turbine.

The water pressure causes the turbine to rotate and generate electricity.

HOW IS HYDROELECTRICTY GENERATED?

head

height difference between source and the water's outflow

vasahin:

- The higher the dam, the higher the head, and the stronger is the pressure that would cause the turbine to generate power.

- When reservoir is not in its full capacity even in high dams, the head is lower.

SMALL-SCALE HYDROPOWER

- run - of - the - river power has become more common

generates 10 MW to 30 MW of electricity.

- further subdivided into minihydro, which can generate <500 kW and microhydro, which has <100 kW capacity.

A diversion structure, called weir, is constructed along the steams to divert water and allow it to flow through a canal, called headrace, into a forebay where sediments can settle.

HOW DOES SMALL-SCALE HYDROPOWER WORK?

TIDAL POWER SYSTEM

- A dam called barrage is built in the tidal inlet and water is allowed to enter during high tide.

-The water is then allowed to be released during low tide.

- As the water flows, a turbine installed at the bottom of the structure generates electricity.

WIND ENERGY

- Air moves from higher to lower pressure as a result of uneven heating of Earth's surface by the sun.

- Hot air rises and cooler air moves down, forming wind currents

- Gust- short - duration, high - speed wind

- Breeze, Gale, Storm, or Hurricane- duration wind with various strengths

kinds of wind energy:

WIND FARM

- A collection of individual wind turbines

- It is connected to an electric power transmission network or power grid.

- Wind speeds ranging from 6.4 m/s to 10 m/s are considered good to excellent.

SOLAR ENERGY

Energy from the Sun

ex. calatagan solar farm

BIOMASS

Energy from burning organic or living matter.

ex. san carlos biopower