Plenty of savings on coffee makers in workplaces

Energy consumption by coffee makers is rising dramatically
Around 35,000 additional coffee makers in Danish workplaces within 2 years; this is the assessment from the Danish Technological Institute based on the current increase in sales and on information from the trade.

The assessment comes in a report produced by the Danish Technological Institute for the Danish Electricity Saving Trust. However, the precise figure of installed coffee makers has not been made available by DAFA (the Danish trade association), which does not issue sales figures on a point of principle.

Growth equivalent to electricity consumption of 20,500 households
The report contains a conservative estimate of the total energy trend in the use of coffee makers from 2007 to 2010. The results show that total consumption of 23 GWh in 2007 will rise to 82 GWh in 2010, which is equivalent to the annual consumption of electricity by 20,500 households.

The estimate is based on the fact that in 2007 there were around 10,000 coffee makers installed, with nearer to 45,000 machines forecast to be in use in 2010. The given assumption is that a coffee maker uses 5 kWh per day per machine.

Check the energy consumption of the machine
The Danish Technological Institute report measured the energy consumption of coffee makers and, on the basis of its findings, recommends that workplaces check the energy consumption and optional sleep functions before making a purchase or agreeing to a service contract. It’s also possible to save a lot of energy by making sure the appliance is switched off overnight.

Look at standby consumption
2 coffee makers were tested in the Technological Institute’s laboratory, where energy consumption was measured at a controlled room temperature. The appliances tested were a Spengler SL-50FB ‘fresh brew’ coffee maker and a Scanomat PRO-4 Compact ‘instant coffee’ maker.

According to the Technological Institute, standby consumption is particularly important as an indication of the overall energy consumption. That is because this is the amount of energy used by the machine when it is idle or, to put it simply, when it is not actually making coffee but is still keeping the water warm – i.e. its energy consumption for the majority of the time, including outside normal working hours.

The standby energy consumption measured for the 2 coffee makers in the test was 0.97 kWh/day for the Spengler SL-50FB and 1.03 kWh/day for the Scanomat, equivalent to a total of 40.6 watts and 43 watts respectively.

1 kWh per day on standby
Merrild Coffee and Wittenborg were also invited to provide machines for testing, but the 2 suppliers declined to participate.

The Technological Institute has nonetheless carried out simple field trials in various workplaces, including tests on 2 Wittenborg coffee makers of different sizes.

Across the board, these coffee makers were found to use more power than the 2 in the laboratory. Amongst other results, a Wittenborg coffee machine of similar size used 99.5 watts in standby, equivalent to 2.4 kWh/day – i.e. more than twice as much as the 2 laboratory machines.

The report concluded that both the Spengler and the Scanomat tested in the laboratory were energy efficient.

According to senior consultant Hans Walløe, the professional expert behind the report, it therefore makes sense for organisations that are about to go out and buy a coffee maker to use the 1 kWh/day standby energy consumption of the 2 test machines as a benchmark for a decent level of energy consumption.

Switch off the coffee 14 hours a day
One way in which users who already own a coffee maker can make savings is to install a time clock, which will switch off the appliance outside normal working hours, at night and at weekends. This also applies to relatively energy efficient models similar to the 2 tested.

A coffee maker in an ordinary office environment will typically only be in use between 7 in the morning and 5 in the afternoon – i.e. for 10 out of 24 hours. If you switch it off for the remaining 14 hours, as well as at weekends, the savings can be around 220 kWh per year for an energy efficient model.

Check the energy consumption of coffee makers
According to the report, workplaces can do a lot to lessen the considerable expense of providing staff coffee. The recommendations are:

• Ask about the energy consumption of the coffee maker, and whether the supplier can provide a test report based on the ‘European Vending Association’ (EVA) test procedure. Coffee makers should not use much more than 1 kWh/day on standby.
• Ask whether there is a save or sleep function, which can be activated at night and at weekends, or alternatively a start/stop clock timer.
• Switch off the coffee maker outside normal working hours, at nights and at weekends. Check the manual, or with the supplier, whether the machine can be time controlled and whether there are any problems connected with this.