Ever built your own oven? Making a solar oven is a great thing to do on a very hot day with lots of sunshine. Make your favourite yummy treats in an oven powered by the sun. A solar oven is a box that traps some of the Sun’s energy to make the air inside the box hotter than the air outside the box. In other words, the solar oven is like a super greenhouse.
This activity will need the help of an adult as the oven can get very hot.
Solar Power is the conversion of the heat from the sun into electricity. It is a renewable energy resource as, unlike coal or oil, it comes from a natural source that is constantly replenished. The wind and waves are two other renewable energy sources. They are also referred to as ‘clean energy’ or ‘green energy’ sources as they do not release carbon into the atmosphere like burning coal or oil does. Moving to more renewable energy sources is a key part of our fight against the Climate Emergency.
Find out a bit more about renewables from the UN’s teen Climate Ambassadors.
Your Solar Oven is an example of how you can harness the power of the sun to provide the energy you need – in this case to do some cooking.
- The shoe box will be your cooker, firstly measure a rectangle around an inch from the edges of the outside of your box lid. Cut three sides of the rectangle, leaving one longer side uncut. The lid will later be positioned to best capture the sun’s energy.
- Next you need to make the inside of our oven reflective to best heat your food and direct the sunlight to the centre. Glue the foil to the inside of your shoe box, (shiny side out). Make sure no cardboard is left without foil. Add a second layer of foil for extra insulation.
- Dark colours absorb the sun’s rays, increasing the temperature inside your oven. Measure, cut and stick pieces of black paper or card to fit the inside walls and bottom of the box.
- Next cover the inside of the lid flap that you created with foil in the same way (make sure the flap is lined separately so it can be lifted up easily).
- Now cut the transparent plastic to be slightly larger than the rectangle previously cut out of the lid. Tape the plastic to the inside of the lid to cover the rectangular cutout. The plastic will trap the heat inside the box.
- Prop the foil-lined rectangle on the lid open and hold it open ( you could try using metal wire or bamboo sticks placed at the corners if it doesn’t stay up alone).
- Place your food, in a pan or a suitable container, inside the box and put the lid on top.
- Position your solar cooker where it will get the most exposure to sunlight. Cooking time will vary depending on the food and the weather.
Remember when you take the food out of the oven it will be hot so wear oven gloves or use a tea towel to remove it.
Cooking in your Solar Oven
You might want to start with some gentle melting, to get the measure of how hot your oven can get. Try melting cheese over nachos, or chocolate and marshmallows together on biscuits. Once you’ve had some melting successes, try some actual cooking – can you get your oven hot enough to fry an egg?
Take it further
If you enjoyed making a solar oven, check out our instructions for making a Tiny Cooker. You might also like to try insulating ice for another experiment in solar heating – this time trying to reduce it!