You'll need

  • A drinking straw
  • Scissors
  • Blu Tack
  • 4 plastic spoons
  • A bamboo skewer
  • A deep, open container, like a plastic or metal mixing bowl (narrow enough that your skewer rests across the top of it)
  • A jug of water
  • A permanent marker

What to do

  1. Cut a piece of drinking straw about 4 cm long. Stick a thick ring of Blu Tack around the centre of the straw.
  2. Cut about half the length of the handle off the 4 plastic spoons.
  3. Poke the handles of the short spoons into the Blu Tack. Space them out evenly. The bowl of each spoon should face the back of the bowl of the next one.
  4. Put the skewer through the drinking straw.
  5. Place the skewer lengthways across the top of the mixing bowl. The spoon wheel should sit halfway in and spin freely.
  6. Pour the water from the jug onto the spoon blades of your turbine. Watch what happens.

Questions to ask

Do the spoons move? Use a permanent marker to mark one of the spoons. Now count the number of times the spoon spins in 10 seconds as you pour water from the jug.

How can you make it spin faster? Try using more or fewer spoons, or pour the water faster or slower. You could also try changing the angle of the spoons.

See if you can find examples of other waterwheels on the internet. Can you model a water turbine on one of these and see if it works better than the one you made with spoons?

What's happening

When water hits a spoon, it transfers some of its energy to the spoon, and the spoon moves. This spins the wheel. Waterwheels have been used for thousands of years to power machines like flour mills and pumps. These days, some waterwheels, usually called water turbines, are used to generate electricity.

Most of Australia’s electricity comes from coal-fired power stations. These generate electricity by burning coal to heat water so that it turns into steam. Fast-moving steam is then used to spin a huge turbine, which drives a generator to create electricity.

Waterwheels can be used to generate electricity. This electricity is sometimes called hydropower, hydro meaning water. Falling water spins the waterwheel, or turbine, and this drives a generator. Many hydropower stations use the powerful flows of water from dams to spin giant turbines. Hydropower is a renewable resource, unlike coal. Also, apart from construction work, it does not add greenhouse gases to the atmosphere, unlike burning coal. Hydropower is a ‘clean’ energy, and does not contribute to climate change.

Did you know

The Snowy Mountains Hydro-electric Scheme in New South Wales is one of the most complex hydropower stations in the world! It took 25 years and more than 100,000 people to build. It generates about 37% of Australia’s renewable energy each year.