Shining Earth™present to Buying Solutions

It was recognised that many have environmental standards or certification such as Buying Solutions Green Ticks, Energy Star, Blue Angel, Nordic Swan etc., so it is hard for a purchaser to distinguish definitively between the environmental credentials of one machine from another. The results of testing undertaken to meet the criteria of a standard are rarely published so, for example, the customer cannot determine whether a machine just meets the criteria for Energy Star, or was well within the required specification. If this data was readily available it would be easier to compare the potential energy performance of one machine against another to make a more informed decision.

To demonstrate the difficulties in determining environmental performance Shining Earth^™ looked in more detail at the potential energy consumption and associated carbon emissions of a fleet of Océ machines being installed at a large local authority and compared them to a range of competitor machines they were replacing. Calculations had to be based on typical monthly volumes to provide the operational printing hours based upon print speed specifications and included assumptions on time spent in ‘ready’ and ‘standby’ modes etc. Energy consumption in the different modes of operations was taken from machine specifications and during this exercise it became evident that consistent terminology is not always used by different manufacturers for the lowest power mode.

The results of the exercise were interesting and raised more queries than providing definitive answers. It became apparent that the energy consumption results were highly influenced by one particular machine and its performance in lowest power mode. By changing the assumptions so that the machines were considered to be fully turned off at night and at weekends meant that the Océ fleet out-performed the competitors.  The Océ machines were, in general, also much faster than the competitors so volume of output would also have a major impact on the results, although this is virtually impossible to accurately predict. Some of the Océ machines were also higher spec in terms of multi-functionality so, therefore, may have made other standalone machines remaining at the council department, such as scanners, obsolete which also could not be quantified.

It was, therefore, concluded that many factors influence the energy consumption of a machine in useit is not possible to calculate accurate carbon emissions without detailed information on application of individual machines and how they are used and managed by an organisation in the field. It is, however, possible to make generic comparisons based upon typical usage and operational assumptions but these should be treated with caution and a clear understanding of the limitations of the assumptions made and how they can affect the resulting picture of environmental performance. 

Shining Earth™’s experience underpins this conclusion whereby previous studies have demonstrated the measured energy consumption of the print machines in use in the field does not always accurately reflect published specifications and data sheets with variables including paper weightsand sizes adding further influencing factors to energy consumption figures.