ENERGY RESOURCES Reassessment Review

Review Directions Go through the PowerPoint by choosing “slideshow” and “From Beginning” As you go through take notes. You must include the following for each resource: What is it How it works Advantages Disadvantages Feel free to take notes in any way you feel is best – using separate note cards, creating a chart, a bulleted list, etc. Memorize the information.

Key Words Energy – being able to do work. Example - food gives us energy, so that we can move Fuel - Fuel is anything that is burned or altered to obtain energy Fuel gauge

Solar power Most of the Earth's energy comes from the sun What is it? Solar power is energy from the sun How it works. There are two main ways that we use the Sun's energy 1. Solar Cells / Panels collect sun light and convert it into electricity. 2. Solar water heating which is when the sun directly heats water.

Why Use Solar power? Advantages Solar energy is free - no fuel, no waste or pollution. In sunny countries, easy to use in remote places with no electricity It is renewable & we won’t run out Disadvantages Can’t collect at night or on cloudy days. Very expensive to build solar power stations.

ENERGY FROM FOSSIL FUELS Fossil fuels are coal oil and natural gas coal oil natural gas What are they? Fossil fuels were formed from dead plants and animals over millions of years. They were quickly buried by sediments in swamps. Over millions of years the pressure & heat turned them into coal oil and natural gas. Coal comes from dead trees and oil and gas from dead plants & animals. When we burn fossil fuels, we’re actually using the SUN’S energy that has been stored as chemical energy underground for millions of years!!! fossils

ENERGY FROM FOSSIL FUELS How they work. Fossil fuels are mined or pumped from deep in the earth. They are burned to heat water and make steam. The moving steam spins a generator and generate electricity.

Why use fossil fuels to make electricity? Advantages Electricity can be generated fairly cheaply. Transporting oil and gas to the power stations is easy. Gas-fired power stations are very efficient. A fossil-fuelled power station can be built almost anywhere.   Disadvantages Pollution. Burning any fossil fuel produces carbon dioxide, which pollutes the air. Mining coal can be difficult, dangerous and ugly. Fossil fuels are a non- renewable energy resource. Once we've burned them all, there isn't any more and our use of fossil fuels has nearly doubled every 20 years since 1900. This is a particular problem for oil, because we also use it to make plastics and many other products.

Wind power What is it? Wind comes from the earth spinning and from warm air rising and other air moving in to replace it. How it works. The moving wind blows the propeller round, which turns a generator to produce electricity We tend to build many of these towers together, to make a "wind farm" and produce more electricity. The more towers, the more wind, and the larger the propellers, the more electricity we can make!

Why use wind power? Advantages Wind is free. Produces no waste or greenhouse gases. The land beneath can usually still be used for farming. Wind farms can be tourist attractions. A good method of supplying energy to remote areas Wind power is renewable. Winds will keep on blowing. Disadvantages The wind is not always predictable - some days have no wind. Suitable areas for wind farms are often near the coast, where land is expensive. Some people feel that covering the landscape with these towers is ugly Can kill birds. Can affect television reception if you live nearby. Can be noisy.

Hydro-electric power What is it? Hydro-electric power is energy generated from falling water. Nowadays there are many hydro-electric power stations, providing around 20% of the world's electricity. How it works. A dam is built to trap water, usually in a river valley. Water is allowed to flow through tunnels in the dam, to turn turbines and thus drive generators to produce electricity. (http://www.wvic.com/hydro-works.htm) 

Advantages - Why use Hydro-electric power? Once the dam is built, the energy is almost free. No waste or pollution produced. Hydropower is renewable and we won’t run out. Water can be stored above the dam ready for when it is needed.

The dams are very expensive to build. Disadvantages The dams are very expensive to build. Building a large dam disrupts the environment causing problems for animals that used to live there. Finding a suitable area can be difficult – what about the people, plants and animals living there already? Water quality and quantity downstream can be affected, which can have an impact on plant life.

NUCLEAR POWER What is it? Nuclear power is energy created from splitting atoms. It is generated using Uranium, which is a metal mined in various parts of the world. Nuclear power produces around 11% of the world's energy needs, and produces huge amounts of energy from small amounts of fuel, without pollution.

Advantages of using nuclear power Nuclear power costs about the same as coal, so it's not expensive. Does not produce smoke or carbon dioxide, so it does not cause pollution. Produces huge amounts of energy from small amounts of fuel. Produces small amounts of waste. Nuclear power is reliable.

disadvantages Although not much waste is produced, it is very, very dangerous. It must be sealed up and buried for many years to allow the radioactivity to die away. Nuclear power is reliable, but a lot of money has to be spent on safety - if it does go wrong, a nuclear accident can be a major disaster. People are increasingly concerned about possible accidents and terrorism. Nuclear energy from Uranium is non-renewable. Once we've dug up all the Earth's uranium and used it, there isn't any more. However, because only small quantities are needed, we have enough for hundreds of years.

GEOTHERMAL ENERGY What is it? Heat from inside the earth. How it works Hot rocks underground heat water to produce steam. We drill holes down to the hot region; steam comes up, is purified and used to drive turbines, which drive generators to make electricity. Geothermal energy is an important resource in volcanically active places such as Iceland and New Zealand. http://keller.clarke.edu

Advantages Geothermal energy does not produce any pollution. The power stations do not take up much space. No fuel is needed. Once you've built a geothermal power station, the energy is almost free. Geothermal energy is renewable. The energy keeps on coming, so long as we don't pump too much cold water down and cool the rocks too much.

Dangerous gases and minerals may come up from underground. disadvantages There are not many places where you can build a geothermal power station. Sometimes a geothermal site may "run out of steam", perhaps for several years. Dangerous gases and minerals may come up from underground.

BIOMASS - ENERGY FROM ORGANIC MATERIALS What is it? Biomass is energy from burning organic materials like wood, trash and manure (poop!). How it works: Sugar cane can be used to make alcohol, which can be burned to generate power Other solid wastes, can be burned to provide heat, or used to make steam for a power station We can use rubbish, animal manure, woodchips, seaweed, corn stalks and other waste

Advantages It makes sense to use waste materials where we can. The fuel tends to be cheap. Less demand on the Earth's resources. Biomass is renewable, as we're going to carry on making waste products. We can always plant and grow more sugar cane and more trees, so those are renewable too. Disadvantages Collecting the waste in sufficient quantities can be difficult. We burn the fuel, so it makes pollution. Some waste materials are not available all year round.