Your school has been challenged by the promoters of “Energy-Saving” week in your local area to cook an egg over a nightlight, using a tripod and aluminium foil

They want to see which group uses the least energy to cook their egg. 

This experiment should take 30–60 minutes, depending on the group.


  • Eye protection.
  • A tripod
  • Kitchen foil (limited to about 0.25 square metre at most)
  • A nightlight or candle
  • Heatproof mats
  • Matches
  • Spoons
  • An empty tin.
  • A top pan balance
  • An egg
  • Sodium chloride (flavouring!)

Health, safety and technical notes

  • Read our standard health and safety guidance here.
  • This is an open-ended problem-solving activity, so the guidance given here is necessarily incomplete.
  • It would be best to use eggs with a lion stamp, as these should be salmonella free.
  • Consider the safety aspects of eating in the lab.
  • Eye protection is advisable when heating anything using a flame.

Possible approaches

Students are given little information about the factors which will affect the speed of cooking. They usually realise surrounding the flame with aluminium foil conserves energy. (By doing so it is fairly easy to prevent oxygen getting to the flame so that it goes out!)

Covering the egg with foil decreases cooking time significantly.

Eggs cook much faster if they are scrambled (mixed) first.

If this experiment could be done in the Home ‘Eggonomics’ department, students could actually eat their results (experiment has cross-curricular possibilities) – the results are often surprisingly edible.

If the foil splits, the reaction gets messy and smelly.

Evaluation of solution

The mass of the nightlight is measured before and after the experiment to see which group has used the least energy.

Suggested write-up

Students could produce a poster for display at the ‘Energy-Saving’ week, showing the steps they took to produce their cooked egg. They might also include some of the actual materials they used.