Earth and Space Sciences Resources: Renewing our interest You need resources to do anything – paper to write on, electricity to recharge your phone, food just to stay alive. Some of our resources can’t be easily replaced and might run out. Using some resources harms the environment, such as climate change caused by burning fossil fuels. Some scientists are coming up with ways of reducing the harm done by fossil fuels and others are developing alternative sources of energy. In this lesson you will investigate the following: • What’s the difference between renewable and non-renewable resources? • How will we meet our energy needs in the future? • What makes our use of some resources unsustainable? • What would you need to set up an egg farm? See if you have the resources needed to complete this lesson! This is a print version of an interactive online lesson. To sign up for the real thing or for curriculum details about the lesson go to www.cosmosforschools.com Introduction: Resources What would you do if you found yourself trapped alone on an island? There are no houses and no people to cook you meals or buy you clothes – and no shops where you can buy them for yourself! All you have are the natural resources you discover on the island: water, plants, animals, rocks, air and sunlight. Your survival depends on how well you use them to supply what you need – shelter, food, tools, and so on. Above all, you need to make sure that you can replace what you use so you don’t run out. The Earth is just an island floating in space. Everything that we humans need has to be found somewhere on the planet. And our survival depends on how well we use its natural resources. One of the things we need in huge amounts these days is energy. Our cars, planes, TV’s and air conditioners are all thirsty for it. Most of our energy comes from burning coal, oil and natural gas but there are two main problems with these fuels. The first is that supplies are limited and will take millions of years to be replaced by natural processes. This means that we’ll use them up within a few generations. The second problem is that burning these fuels is changing our climate by adding to the amount of carbon dioxide gas in the air. Some countries are now trying to capture the gas and store it deep underground where it can’t pollute the atmosphere. But this can’t fix the first problem and we’ll have to rely more and more on sources of energy that won't run out, such as sunlight, wind and flowing water. Only by understanding the natural resources we rely on every day can we hope to survive on our island planet. Read or listen to the full Cosmos Magazine article here. Question 1 Describe: Open your school bag and place the contents on the desk in front of you. These objects are just some of the resources you bring to school so you can study. Other resources are supplied by your school – for example, the buildings that protect you from sun, wind and rain or the chairs you sit on. List all the resources you need to study at school and see if you can also write down some of the materials needed to make them. Resources provided by you Materials Resources provided by your Materials school Gather: Resources 0:28 Natural resources The 3,000 km long World Solar Challenge is a car race with a difference. Instead of burning petrol, the futuristic cars use solar panels to collect energy from the Sun! The race sparks interest in new uses of our resources. Every day you rely on certain things to keep you alive and healthy – air, food, water, warmth and shelter, for example. All of these are natural resources that need to be supplied by the world around you. They can be divided into two categories: Renewable resources can be replaced by natural processes within a lifetime – that is, about 80 years. Non-renewable resources take longer to be replaced and so are more likely to be used up. The sunlight used by cars in the World Solar Challenge is a renewable resource. This is because the Sun shines continuously and will continue to do so for billions of years. The petrol used by ordinary cars is a non-renewable resource – you'll discover why a bit later on. Left: Solar-powered computers are used in schools and rural communities in Uganda, Africa. Right: Design for a "solar tent" that would allow campers to use solar energy to recharge their phones and other electronic devices. Renewable energy Energy is one of our most important resources. It comes in a wide variety of forms, both renewable and non-renewable, but first we will look at some renewable forms. When energy comes directly from the Sun as light and heat it is called solar energy. Plants use solar energy to create food, making this renewable resource essential for almost all life on the planet. Question 1 Question 2 Decide: Energy from the Sun is a useful resource because: Remember: Solar energy is renewable because: it provides warmth to humans and other animals. it can be converted into electricity. it provides light so we can see. it's replaced quickly, in less than a human lifetime. it is used by plants to produce food. it takes millions of years to be replaced. All of the above. it's only available during the daytime. Question 3 Identify: Name one advantage and one disadvantage of solar-powered cars compared to petrol cars. Some other types of renewable energy are described in the video below. The word "kinetic" describes the energy that something has whenever it moves. In contrast, "potential" energy is energy that is stored up and then released later. 2:01 Question 4 Complete: Use information from the video to name one advantage and one disadvantage of each type of renewable energy. Note: A lot more could be said about the advantages and disadvantages of these forms of renewable energy. Type of renewable energy Advantage Disadvantage Wind Water – wave May harm the nearby marine environment. High cost of maintaining the equipment in rough seas. Water – tidal Water – hydroelectric dams Geothermal Solar Generates less energy on cloudy days and none at night. The Tavan Tolgoi coal deposit in southern Mongolia is one of the largest in the world. Non-renewable energy Although renewable energy sources are becoming more widely used, over 85% of the world's energy in 2012 was still supplied by non-renewable sources. There are two main types of non-renewable energy that are used to generate electricity: Fossil fuels – coal, oil and natural gas – are burned in traditional power plants. Nuclear energy relies on limited supplies of minerals containing unstable elements such as uranium. We'll focus here on fossil fuels and start by taking a look at how they are formed. 2:25 Question 5 Label: The process that forms fossil fuels is shown below. Use the following labels to fill in the blanks: natural gas | plants | pressure | coal | heat | oil Question 6 Explain: According to the video, how long does it take for heat and pressure to turn buried plants into fossil fuels? Use your answer to explain why fossil fuels are a non-renewable resource. Did you know? Burning fossil fuels releases carbon dioxide (CO2 ) back into the atmosphere after being trapped in fossilized plants for millions of years. This adds to global warming which is expected to raise sea levels and increase the risk of droughts and tornadoes, among other things. The Cosmos Magazine article explains how the United States and China are now trying to "capture" that carbon dioxide and store it underground. But even if these plans succeed, fossil fuels are a non-renewable resource and are expected to run out in 50 to 100 years. So the pressure to develop renewable energy sources remains. Question 7 Classify: Identify whether each of the following sources of energy is renewable (R) or non-renewable (N). Process: Resources Left: Veta la Palma is a sustainable fish farm in southern Spain that is also home to threatened bird species. Right: A farm in Port Augusta, South Australia, that uses desalinated seawater and solar power to grow tomatoes. Sustainability Energy is just one of the natural resources that we rely on every day to meet our needs. Others include: air water rocks minerals soil living things Understanding whether these resources are renewable or not is important. If we use a resource more quickly than it can be replaced then sooner or later it will run out. This might create a serious problem for us or for our children and grandchildren. Some of the ways we use resources are sustainable, which means that we can keep using them for generations without using them up. Most renewable resources are sustainable – but not always. For example, salmon are a renewable resource because they can be replaced by a new generation each year. But overfishing has caused the population of wild salmon to decrease dramatically because they can't be replaced quickly enough to meet demand. Most non-renewable resources are unsustainable – but not always. For example, soil is a non-renewable resource because it often takes centuries to form. But we can still use soil sustainably to grow vegetables if we protect it from being washed or blown away and use fertilizers to replace the nutrients. To explore these ideas more we'll jump on a plane and go on a journey..