How does it work?

Energy use contributes up to half of the carbon dioxide emissions produced by schools. To operate effectively all schools need to be comfortable places to work where pupils can access high quality learning experiences. This means that classrooms have to be properly heated and ventilated, well lit, and give pupils' access to appropriate ICT and other technologies. All these require energy. Choices about how energy is managed and the sources of energy used can have a great impact on the carbon footprint of a school.

Water use does not contribute greatly to the school’s carbon footprint. The water companies do use energy to clean water and in some cases pump water from its source, and this energy does create carbon dioxide emissions but these are not significant in a school context. However, water conservation should be seen as good practice, as in a time of climate change where long hot dry summers may become the norm in the UK, water resources are under increasing pressure.

What data is needed?

To calculate the CO2 emissions from your use of energy and water the Carbon Detectives Team will need to collect information about:

  1. Energy use:
    • How much electricity has the school used in the last 12 months measured in kilowatt hours? They will also need to find out if the school uses renewable electricity and what this is as a percentage of the total.
    • How the school is heated – oil, gas, wood or coal – and how much energy has been used for heating.
  2. Water use - how much water the school has used in the last 12 months measured in litres or cubic metres.

Once the data has been entered it is multiplied by carbon conversion factors to give the impact in kilograms of CO2. For example, one kWhr of heating produced by gas produces 0.19 kg of CO2 compared with 0.36 kg CO2 if produced by coal.

Energy and water facts and figures

  • Low-cost or no-cost improvements should be the first step in optimising energy and water use. These involve influencing user behaviour, target-setting to improve energy and water management, improving energy and water efficiency, purchasing renewable energy, and making the best use of rainwater.
  • Lighting accounts for around half of the electricity used in a typical school. In many cases 38mm diameter fluorescent tubes can be replaced with 26mm versions which use 8–10 per cent less electricity. Compact Fluorescent Lamps (CFLs) use 80 per cent less electricity than tungsten bulbs and last much longer.
  • Turning down the schools heating thermostat one degree can save up to 10 per cent on heating costs.
  • The fastest growth in carbon dioxide emissions in schools may come from electricity consumed by ICT equipment such as interactive white boards, digital projectors and so on.
  • Schools in England spend approximately £61 million per year on water. The average annual water bill for a primary school with 250 pupils is £1,630. A secondary school with 1,000 pupils spends between £3,200 and £8,600. Careful water management could cut a school’s water consumption by half.

What individual pupils can do

  • Switch off unnecessary lights when leaving a classroom for more than 10 minutes.
  • To cool a classroom, turn down the heating rather than open a window or door.
  • Make sure electrical equipment is switched off when not in use and not left on standby.
  • Turn off taps fully. In one day a dripping tap could waste enough water to fill a bath.

What a school community can do

  • Develop and promote energy and water efficiency policies – for example have a policy to buy only A-rated electrical equipment.
  • Ensure low energy lighting is used and replace old light bulbs with more efficient ones.
  • Turn down the school heating thermostat and install individual radiator thermostats to allow individuals to manage the temperature of their own classroom.
  • Switch to a renewable energy supplier and/or produce your own renewable energy.
  • During any refurbishment or new building projects invest in energy and water saving equipment.
  • Collect rainwater from school roofs to be stored in water butts or larger tanks, this could be used for watering in the school grounds, flushing toilets and so on.

To influence government thinking and policy-making, pupils can:

  • Promote and share energy and water efficiency practices with the local community and make the school a centre of sustainability good practice.
  • Talk with their local council and see if their school can be part of any bulk purchasing deals for renewable electricity.
  • Write to the local MP/MEP and ask about the current policies and agenda for tackling the UK’s carbon dioxide emissions, highlighting the actions that their school is taking to reduce its carbon footprint.