Shower Power


The purpose of this lab is to calculate the cost in dollars of a typical shower using knowledge of specific heat capacity and introductory lab measuring skills.


Step 1 - Collect a sample of shower water set to the temperature that you enjoy the most and measure the temperature.

Step 2 - Using a bowl or bucket collect the volume of water that comes out of the shower in 5 seconds.

Step 3 - Time the length of your average shower. (The truth will likely be somewhere between the length you believe it is, and the length your parents believe it is)

Step 4 - Locate the room in your house where the hot water heater is stored and measure the room temperature of that room.


Determine the total volume of water required for one of your typical showers.

Using the temperature of your shower water and the temperature of the room where the water heater was stored, determine the change in temperature of the water.

Calculate the heat energy required to heat up all of the water for your shower.

Research the cost of energy in your local area, which will likely be measured in cents per kWh. kiloWatt hours can be converted to Joules so that you can determine the cost in dollars for each Joule of energy.

Calculate the cost of your shower.


How does the cost of your shower compare to that of your peers?

Look at the data of others who completed this task. To reduce the cost of a shower do you feel it would be better to reduce the time or reduce the temperature?

Learn how to use your own hot water heater. Explain how you can reduce or increase the maximum temperature.