WEEK 2
Energy everywhere Time to think about future energy. FEELING ENERGETIC?
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Imagine how different our lives would be without energy. Did you know that the energy from your power point comes from different sources? Energy can be ‘renewable’ or ‘non-renewable’. Non-renewable sources are materials buried in the ground such as coal, gas and oil (also called ‘fossil fuels’). Fossil fuels are formed from plants and animals that lived millions of years ago. Most of the energy we use today is generated through the burning of fossil fuels. It’s pretty
reliable and cheap, but releases greenhouse gases and pollution into our air. Another downside is that once all fossil fuels from the ground are used up, they are gone. It takes millions of years for the fuel to form. Renewable energy can be made from the sun (solar), rivers and oceans (hydro), wind, plants (biomass) and our planet’s hot centre (geothermal) sources – which will never run out. This renewable, green energy releases fewer greenhouse gases into the atmosphere. It already
provides around 16% of global energy supply. Exploring more renewable energy ideas will help move to a cleaner energy future.
of natural causes like volcano eruptions, changing ocean currents and variations in Earth’s orbit around the sun. But over the last century temperatures have increased by 0.8 degrees Celsius – this is really fast compared to historical changes. Scientists who study this around the world have found that this
can only be explained by extra greenhouse gases produced by humans. As population grows and people consume more, we need more energy, so we burn more fossil fuels and release more greenhouse gases. The greenhouse gas blanket is getting thicker and just like a great big doona is trapping too much heat.
THE GREENHOUSE EFFECT There are some gases in our atmosphere that capture heat from the sun, we call them ‘greenhouse gases’. The five main greenhouse gases are steam, carbon dioxide, methane, nitrous oxide and ozone. They act like a blanket around the planet and keep the world at comfy temperatures. Throughout history, temperatures on Earth have always changed. They have risen and fallen because