Why not working 9 to 5 is damaging the Planet

The world has changed. We used to "clock on" at 9am and "clock off" at 5pm - now we work longer hours and our buildings are open for even longer. But have you considered the effect this has on energy use and carbon emissions?


Dolly Parton (and Sheena Easton) had hit records with the song ‘9 to 5’, bemoaning the lot of office workers required to be at their desks for those prescribed hours.


Well that used to be the standard office hours throughout the West for many years but thing have changed and the concept of “flexible hours” has become close to universal. This is generally seen as beneficial as it give greater freedom to the workers, more availability to customers and added benefits like reduced travel congestion, increased utilisation of assets and apparent increase in resource.

Additionally, companies operating internationally gain more overlap between time zones enabling better communication and cooperation. (I well remember working late in a Glasgow office and answering a phone call from the American Head Office at 8pm local time and them being surprised that the person they wanted had left – and Americans have time zones within their own country).

Increasingly, businesses are operating longer and longer hours – and the latest disputes on the London Underground as it prepares for overnight operation show this trend is likely to continue.

But have you considered the effect this has on energy consumption? When buildings were only occupied from 9 to 5, the heating and air-conditioning could (usually) come on around 8am and go off at 5pm (at the latest). Now with occupation from 7:30 am to possibly 10pm, the system will need to be energised from 6:30 am to 10pm or so. That means 9 hours becomes 15½ hours -over a 70% increase. And that doesn’t take into account the tendency to work at weekends.

Now, the technical amongst you will realise that 70% increase in hours doesn’t mean a 70% increase in energy consumption due to the high proportion required to initially bring the building into a condition for occupation from its rest state and obviously good control strategy like optimum start and finish will have an effect.

But because the extended hours will generally have colder exterior temperatures (and hence higher heat loss), the extra usage will be more than you might expect. To add to that, because there will be more hours of darkness, the lighting load on a well controlled building will be MUCH greater.

Now, because the extension of operating hours is a commercial decision involving a lot of factors, most energy and sustainability managers will have little influence but they should at least try to have their voice heard and the energy and carbon implications included in the calculation.

Perhaps when HMG are considering increasing Sunday trading hours they should consider the effect on their Climate Change Policy?

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