Importance of a Desktop Study

A Desktop Study provides an overview of the way in which water is currently being used and billed.

Included within the study is:

  • Tariff checking
  • Trade effluent costs
  • Standing charges
  • Fixed and surface water disposal charges
  • The possibility of reducing standing charges by meter optimisation

 

The above graph shows what  is refered to as a "Nightline" consumption profile. We will have installed a  logger at a point on the system that records water consumption over a set period. We are looking  for the period when water use  is at a  minimum. This is usually at night and is therefore called the minimum nightline.

The site owner will have an idea whether there will be some known constant use that  extends into the weekends. Alternatively there is an expectation that for certain periods,  particularly at weekends, the consumption should approximate to zero.

The above graph, which is a real example, comes from a recent project where we identified a number of leaks, some of  which were getting progressively worse. This can be seen in the graph above where the lowest level of consumption at the weekend is marginally higher week on week.

As can be seen the profile is gradually increasing from 22 to 28m3 per hour. To an extent the same can be seen on weekdays though this is masked by ongoing processes and changes in water use during the day.

This audit then identifies the potential for savings based against

  • Occupancy
  • Processes and system controls
  • Catering, and vehicle washing
  • Heating and air conditioning facilities

Finally, supply confirmation is undertaken and this is cross-checked to the billing information in order to verify the data analysed..