Energy Audit
Find out what in your house is actually costing money.
2 weeks🔬 Science🔢 Math🧭 Life Skills
What you need
- a recent energy bill
- the labels on your appliances
- a notebook
Nothing to buy and nothing to print — if you do not have one of these, swap it for whatever you do have.
The steps
Day 1
Find the rate
Find the price per kWh on your bill. Write it down with its units.
🔢 Write the number down
Day 2
List the appliances
List ten appliances. Find the wattage on each label.
📋 Make a list
Day 3
Estimate hours
Estimate how many hours a week each one runs. Be honest, not optimistic.
📊 Make a chart or table
Day 5
Do the maths
watts / 1000 x hours x rate = cost per week. Do it for all ten.
📊 Make a chart or table
Say this: “Kilowatt-hours are just watts, for an hour, divided by a thousand.”
Day 7
Rank them
Sort the table by cost. Is the biggest one what you expected?
📊 Make a chart or table
Day 9
One recommendation
Recommend one change, and show how much it would save per year.
✍️ Write a few sentences
How to score it
You score this, not us. Pick the description that actually matches what they did.
Data
- 1. Guessed wattages
- 2. Some real wattages
- 3. All from labels
- 4. All from labels, with hours justified
Calculation
- 1. Units confused
- 2. Arithmetic mostly right
- 3. Correct throughout
- 4. Correct throughout with units carried at every step
Recommendation
- 1. Generic advice
- 2. Specific to one appliance
- 3. Specific with a saving
- 4. Specific, with an annual saving and a stated assumption
With more than one child
Younger children read the labels and record; older ones do the arithmetic and the recommendation.
What goes in the portfolio
A ranked table of appliances by estimated running cost, with one recommendation and the arithmetic behind it.