Modern industrial countries use energy to:
1. provide electricity,
2.power vehicles, and
3. run technology that we depend upon.

The main energy source today is the use of nonrenewable fossil fuels. These are being rapidly depleted.

Today, it is imperative that we develop renewable resources in response to the fossil fuel crisis. The following slides present information on alternative energy sources.

Nuclear energy is the energy released during nuclear fission or fusion, especially when used to generate electricity. Nuclear energy produces electricity that can be used to power homes, schools, businesses, and hospitals. However, the byproduct of nuclear energy is radioactive material.

In 2011, nuclear power provided 10% of the world's electricity. However, many have now ceased operation in the wake of the Fukushima nuclear disaster while they are assessed for safety.

Flowing water creates energy that can be captured and turned into electricity. This is called hydroelectric power or hydropower.

The most common type of hydroelectric power plant uses a dam on a river to store water in a reservoir. Water released from the reservoir flows through a turbine, spinning it, which in turn activates a generator to produce electricity. One downfall of building dams is the impact on the environment. Also, it s important to maintain the dam properly to avoid breakage leading to floods.

But hydroelectric power doesn't necessarily require a large dam. Some hydroelectric power plants use a small canal to channel the river water through a turbine. Another type of hydroelectric power plant - called a pumped storage plant - can even store power.

A small or micro-hydroelectric power system can produce enough electricity for a home, farm, or ranch.

Geothermal energy has been used for thousands of years in some countries for cooking and heating. It is simply power derived from the Earth's internal heat.This thermal energy is contained in the rock and fluids beneath Earth's crust.

These underground reservoirs of steam and hot water can be tapped to generate electricity or to heat and cool buildings directly.

Geothermal Energy is also available near volcanic activity. It uses the magma that heats underground water and produces steam to harness energy for electricity. Iceland, Italy,
Japan, and New Zealand all use geothermal energy.

Advantages:
1. It can be extracted without burning fossil fuels.
2. It is available 365 days a year.
3. There is an 80% savings over fossil fuel use.
Disadvantageous:
1. May release of hydrogen sulfide, a gas that smells like rotten egg at low concentrations.
2. Although geothermal sites are capable of providing heat for many decades, eventually specific locations may cool down.

Solar Energy harnesses the energy of the sun. One popular way is to use solar panels. Have you seen solar panels on any of the houses in your neighborhood? I have!

Power plants using solar panels are being set up in deserts around the world.

Solar energy use has surged 20% in the past 25 years. Japan, the US, and Germany are the major markets.

Advantages:
1. Pollution and noise free
2. Versatile - can work in far out spaces such as satellites orbiting the Earth or isolated cabins.
3. It is becoming less expensive.

Disadvantages:
1. Needs a storage device or battery to work at night.
2. Cloudy weather can make it unreliable during the day.
3. Require land area to collect sun's energy.

Wind Energy has been used since the ancient times. Examples are sails on a boat and windmills. The only thing that has changed is the appearance of the windmills!

Windmills are being set up around the world: on ocean and on land. Have you seen them driving along the Turnpike?

Some people do not like the sight of windmills, but they are an effective way to produce energy as the wind is always blowing.

Today, wind turbines are increasingly used to harness electricity from the breeze. Wind turbine power only provides a small fraction of the world's energy - but it is increasing 25% a year. The biggest wind turbines generate enough electricity to supply about 600 U.S. homes.

Germany has the most installed wind energy capacity, followed by Spain, the United States, India, and Denmark. Development is also fast growing in France and China. PA has several sites of windmills along the tops of the rolling mountains.

Industry experts predict that if this pace of growth continues, by 2050 the answer to one third of the world's electricity needs will be found blowing in the wind.

Disadvantages:
1. Noisy
2. Dependent on wind

People have used biomass energy—energy from living things—since the earliest “cave men” first made wood fires for cooking or keeping warm.

Biomass is organic, meaning it is made of material that comes from living organisms, such as plants and animals. The most common biomass materials used for energy are plants, wood, and waste. These are called biomass feedstocks. Biomass energy can also be a non-renewable energy source.

Advantages:
1. Clean, renewable source
2. Initial energy generated from the sun; biomass material can regrow in a short amount of time
3. Sustainably grown trees and crops can offset carbon emissions; some biomass can be harvested on marginal lands that do not compete with food crops.

Disadvantages:
1. Most biomass requires arable land to develop
2. Old growth biomass is more useable; this takes time
3. Has a lower energy density than fossil fuels
4. Burning biomass can release carbon dioxide