PhD Thesis - Energy Systems Research Unit - University of Strathclyde

Figure 7.2 Degree-Days Versus Monthly Fuel Use [6]
A best-fit line is then drawn, and the point of intercept of this line with the yaxis
gives the monthly fuel use for hot water and cooking. Multiplying this
number by twelve gives the annual non-space heating fuel use, and subtracting
this value from the total annual fuel use gives the annual fuel use for space
heating. To find the total heat demand, an efficiency factor must then be
applied, relevant to the type of fuel and plant used to gain the original
consumption figures. This figure can then be used to scale the annual profile.
The annual fuel use for water heating (without cooking fuel use) must be
determined for each individual case from the annual non-space heating fuel use.
As this does not tend to vary greatly throughout the year, daily profiles may be
produced for weekdays and weekends based on occupancy and typical
behaviour, and these are then used to produce an annual profile. Again an
efficiency factor must be applied to the annual fuel use figure, based on the type
of fuel and plant used for the original consumption figures, and the overall
annual hot water demand can then be used to determine an annual hot water use
profile. Parts of these profiles can then be used relevant to the chosen timeframe
of the study.
The demand definition window gives the option to load demand data from a
database, import a profile from another source, or specifically design a profile.
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