We have removed 74 fluorescent tubes from the lights in the production area. Even with just one of three tubes remaining in each fitting (as in the left-hand row above), you can see that we still have plenty of light. We left two tubes in the fittings on the right above the packing area, where task lighting is needed.

Each tube is 36 W, so the power reduction is 2664 W. If the lights are on 10 hours per day, 5 days per week, this will save 6926 kWh of electricity per year.

This represents a saving of 2283 kg of C0₂ emissions* and a cost saving of around £690 per year.

You can see the energy and temperatures in the building at http://www.picotech.com/dynamic/.

* 2283 kg of CO₂ emissions is about the same as a Mini Cooper D emits in 21,000 km.

The building was previously used as a PCB assembly factory, so the lighting in the production area was set up with a much higher intensity than the normal lighting for an office. The second problem was that the previous owners worked on a shift system, so the HVAC (heating, ventilation and air conditioning) was running 24/7. We have started by removing some of the lighting tubes to return the area to normal office conditions. In the despatch area we removed two of the tubes from each three-tube light fitting. We estimate that we have removed 3000 watts of lighting, saving us around £1000 per year.

We changed the heating timer to come on at 6am on Monday and go off at 4pm on Friday. At other times it will be on from 7am to 5pm on weekdays and off at weekends, except in the development office.