PhD Thesis - Energy Systems Research Unit - University of Strathclyde

the transformation process models the electrical energy consumption during anysingle hour as a single ‘On’/‘Off’ occurrence. Future work will be aimed at improvingthis modelling process, by producing a system whereby electrical energy consumptioncan be sub-divided into multiple ‘On’/‘Off’ occurrences. Figure 2.7 shows theresulting 1-minute profile when applying the Stage 2 transformation method to thehourly consumption data of an 85 Watts CRT TV.Fig. 2.7 - Minute resolution for the power demand of an 85 Watts CRT TVFor those appliances with complex demand patterns, such as dishwashers andwashing machines, appliance cycle patterns presented by Stokes in [27] wereemployed. The data presented by Stokes provides the minutely power demand overthe duration of a whole cycle for different appliances and for different cycles. Inorder to decide which particular cycle was to be selected, the electrical energyconsumption derived from Stage 1 was matched to the total electrical energyconsumption per cycle calculated using Stoke’s patterns with the closest matchyielding the selected pattern. Again the start of the cycle is awarded on a randombasis following a uniform distribution. This time however since the cycle can belonger than one hour, a single cycle may continue over to the following hour.Finally, the demand which in Stage 1 was awarded to an unspecified miscellaneouselectrical demand is assumed to follow an ‘On’/‘Off’ pattern with P On-App(z) chosen atrandom from a range of 50 Watts and 2,000 Watts which roughly covers the steadystatepower demand of most domestic appliances [27]. Again the start of the cycle is51