PhD Thesis - Energy Systems Research Unit - University of Strathclyde

5.1.2 Storage and Refuelling Options
As vehicles have onboard storage, it is unrealistic to model them as continuous
users of fuel. Instead they require refuelling when their tank is running low, or
at certain times each day, depending on the users requirements. Therefore, the
initial fuel level as a percentage of the tank capacity must be known, and a
refuelling method must be defined. Options for refuelling given in the program
are, refilling to maximum when the level falls below a given minimum
percentage, or choosing to refuel at the same time or times each day. If
continuous use is to be analysed, the options to always keep at maximum or an
input minimum, where possible, are also available. These options are available
for all types of vehicle, except electric vehicles, whose recharging is a separate
case with specific considerations, which is described later.
The amount of storage available on the vehicle is also an important factor when
considering fuel use and refuelling profiles. This is not often quoted as a storage
amount, and where these figures are available, they are again subject to
confusion due to the different storage methods for gases. However, a parameter
that is widely available, which is directly related to the storage capacity of the
vehicle, is the driving range between refuelling. If the range and fuel
consumption of a vehicle, and the number of vehicles, are known, the total
available onboard storage capacity can easily be calculated using Equation 5.3.
This parameter is required for the vehicle use algorithm described later. Where
more than one vehicle is being used, an even distribution of use across these
vehicles is assumed.
Total Storage = (Number x Range x FC) (5.3)
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Where Total Storage = Total storage (litres, litres(eq), or kWh)
FC = Fuel consumption (litres/100km,
litres(eq)/100km or kWh/100km)
Range = Range (km)
Number = Number of vehicles
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