with Mike Sewell, energy services director


People often use the words “energy” and “electricity” as one and the same. But “energy” covers all sources that run a building. This includes electricity, oil and gas, as well as renewable sources.

Did you know the energy used to generate heat in a commercial building can emit just as much carbon every year as when generating electricity in the same building?

Typical energy consumption in a commercial building over 12 months:

  • Space heating 50%
  • Lighting 15%
  • Hot water 15%
  • Computing 7%
  • Cooling ventilation 6%
  • Catering 4%
  • Other 3%

Providing heat and warmth in a more sustainable and controlled way delivers the greatest impact on reducing your energy costs and carbon emissions. It’s also one of the cheapest options for mitigating climate change. So, where can you make changes in your workplace as we head through the winter months?

Three key things to do:

1. Support your employees to understand the difference small changes can make

People are as fundamental to demand reduction as the efficient use of heating, power and light. Allowing building users to understand how heating fits in to the wider energy management plan will go a long way in supporting sustainable energy consumption.

  • If your main source of heating is central then let your building users understand that adjusting individual radiators across the floors can impact the temperature balance and throw out the central heating.
  • Prohibit the use of electric under desk heaters as these are extremely inefficient. Allow building users to understand this, and encourage those who feel the cold easier to bring in extra layers.

2. Set correct operating temperatures on hot water distribution systems

Temperature controls for central heating systems are critical if you are to minimise energy consumption by your hot water boilers. If the temperature is set too high, unnecessary energy is being consumed. For example, if a temperature of 50–60 degrees celsius is required, site facilities management teams often set an average operating temperature of 85 degrees celsius just to be on the safe side.

Actually, 70–75 degrees celsius would suffice most of the year and this extra 10 degrees celsius results in 5–10% excess energy consumption.

3. Improve the installation and operation of your hot water boiler plant

Heating in commercial buildings often accounts for over 50% of total energy consumption, and hot water generation makes up a large percentage of this. In many office buildings, boilers and hot water pipe networks are often not designed with energy efficiency in mind. Many are also poorly installed and not operated in the most energy efficient manner. As a result, significant energy is wasted. We estimate up to 30% of the energy consumed by boiler and hot water distribution systems in UK commercial buildings could be saved each year. With a saving like this, the improvement and installation costs can be returned in as little as three to eight years (depending on what is installed and the heating needs).

Read our Winter Readiness guide here for more helpful tips for your business and people to weather the winter.



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