The sun emits about 3.86 x 1026 watts of energy at any given moment. To give you an idea of how much energy this really is, the energy produced each hour could provide power to the whole world for an entire year!
In recent years, solar cookers have become very popular in 3rd world countries, especially in Africa where there is sunshine all year round and the design has developed over time. The solar ovens were brought in to help tackle deforestation and they allow families to spend more time together instead of having to go out and search for firewood.
So here is how I made my solar oven so you can try it in your own time too:
What you need to buy:
- Shallow box with a lid
- Tin foil
- Clear tape
- Cling film or clear plastic
- Black paper
- Some sort of wooden stick
- Food to cook (We had biscuits, chocolate and marshmallows)
- Get a shallow box such as a pizza box and cut a flap in the lid. Cut along 3 sides, about an inch from the side and then push the flap up
- Cover the hole you have created from the flap, with clear plastic creating an airtight window in the box
- Cover the inner side of the flap with tin foil and attached with sticky tape
- Line the bottom of the box with black paper. This is what your food will sit on
- Put your food in the oven and close the lid
- Sit back, enjoy the sun and wait for your food to cook
So how does the solar oven work?
The tinfoil on the inside of the lid helps to reflect the sun’s rays into the box, so make sure you adjust the flap until you can get the most sunlight reflecting into the box. You can prop it up with a stick if the flap keeps falling down. The clear plastic creating the window multiplies the sun’s rays and the black paper inside absorbs the heat helping to make the oven even hotter.
It is suggested that solar ovens should be used in temperatures above 29ºC which makes it perfect for counties in Africa. The day we made our oven it went up to a mighty 26ºC the hottest day of the year so far and possibly the closest we were going to get to that 29ºC in England!
Once we set up the ovens we left the s’mores for 40 minutes. The chocolate melted really well but we should maybe have waited longer for the marshmallows to melt more, but all the same they were super tasty and went down a treat in the office on a Friday afternoon.
My top tips for making a solar oven
Make sure there is a responsible adult around to cut open the lid in the box.
Wear sunscreen if it’s a hot day as you’ll be out in the sun for a while.
If it’s a windy day, then prepare your oven inside before taking it out or you’ll be spending time running after runaway plastic and paper
Be patient, food takes time to cook