Often classroom temperatures are higher than heating system set temperatures. This discrepancy may suggest that your school's thermostats/temperature sensors for the heating system are in a particularly hard to heat part of the school, such as a draughty corridor or school hall.
On average 50% of school's gas consumption is out of school hours in the evenings or early mornings, weekends and school holidays. This out of hours use is generally due to:
pessimistic or faulty frost protection (heating to prevent the water pipes freezing during very cold weather)
incorrect or poor heating system control.
Reducing out of hours gas consumption is an easy way for schools to reduce their energy bill for little or no cost.
Aim of the investigation
To find out how classroom temperatures vary across a 7 day period to identify whether energy is being wasted in your school.
Low cost temperature data logger (eg https://www.loggershop.co.uk/product/utrix-16-usb-pdf-multiple-use-temperature-data-logger/). If your school does not have a temperature data logger, you could adapt this experiment to use a normal thermometer and take readings at the beginning, and end of the school day and at lunchtime. This will give you less information across the school day, and no information for out of hours, but will still be worth carrying out.
A PC or Laptop computer to analyse the data generated.
Can you write a method that will make your measurements accurate and fair? Think about where to position your temperature logger in the classroom. To get a good overview of the temperature in the classroom, the temperature logger should be away from any radiators, spotlights, air conditioning ducts, windows and poorly insulated outside walls. It should not at any time be illuminated by direct sunlight. It should be out of easy reach from fellow pupils, and kept in the same position during your monitoring exercise. What are your control variables for this experiment? Ideally radiator thermostats should be kept in the same position during your monitoring exercise, and not used as a heating on/off switch for individual classrooms.
Can you use your data to calculate the following:
The mean classroom temperature.
The mean temperature during school hours.
The mean temperature outside of school hours
The daily range
Can you compare your temperature measurements with the Energy Sparks charts showing gas consumption? The gas consumption charts should give a clear indication of when the heating comes on and off in your school. How is this correlated with classroom temperature?
What do your results tell you about classroom temperatures and energy use at your school? Give your evidence for your conclusion. How can you use the information you have learnt to save energy?
Next Steps to save energy
If classroom temperatures are consistently higher than 18°C during the school day, can you ask your school site manager to turn down the heating system set temperature? For every 1°C you reduce the temperature you save the school about 10% of its heating costs.After the heating is turned down, you could continue to monitor classroom temperatures to see the impact of the change.
Evaluate how you carried out the investigation and what could be improved.
Consider the impact outdoor temperatures have on indoor classroom temperatures. Does your school have a weather station with outdoor temperatures recorded regularly? If so, compare the data from this with your classroom temperature results. If your school doesn't have a weather station, can you find weather data for your area online. Weather data for the Bath area can be downloaded at http://www.paulwilman.com/previous_data.php
Extend your monitoring exercise to other areas of the school. Many schools have buildings of different ages with different levels of insulation and ventilation. South-facing rooms are subject to solar heat gains (natural warming from the sun). Solar heat gains might produce a situation where there is significant difference from one side of a building to the other. Investigate whether these factors make a difference to classroom temperatures.
Repeat this monitoring exercise at a different time of year. Although this activity should always be carried out at a time of year when your school heating is running, compare the results you obtain during a period of cold weather with the results obtained during milder spring or autumn weather.