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Step 6: Develop an overview of total energy consumption

Collating the environmental impact and costs of your transport operations is the objective of this step. In particular, the outcome should be a clear and certain picture of the amounts of fuel used in litres, their average buy prices and total costs to the business over the period, usually the 12 months of your financial year.

Collate invoices for volumes purchased, by period, by vehicle

  • Road diesel, collect the volumes purchased, stock on hand (in on-site bowsers) in litres.
  • Green Diesel, as above, but check carefully as this fuel is used in refrigeration units and auxiliary power units where it’s difficult to independently check usage.
  • Petrol, typically used in company cars, look for fuel card and expense receipts totals.
  • Propane Gas Canister usage, look for gas supplies used to heat and power mobile tools.
  • Alternate fuels, LPG, where alternate fuels such as bio-diesel or LPG are being used, either wholly or mixed with petrol and diesel, be careful to separate the numbers by volume, so that their reduced environmental impacts can be accounted for.

Once you have the totals for each fuel type, you need to ensure the amounts used by each vehicle are recorded and similarly reported. If your company has a fuel card or on-site bowser, collect this information from their reporting systems as well, for comparison and checking later.

Compare prices paid to budget and expectation

Budgets may have been based on a lower price for each fuel, seek out the volume assumptions along with the prices expected to paint a picture of energy usage perceptions in your business.

This step is vital, as it may highlight fuel shrinkage; that is the siphoning off of fuels loaded on to vehicles in your depot, once they are out on the road.

Correlate usage in litres to total productive work

Once you are certain of your volume usage, collect the figures for useful work produced, as your company understands it e.g.

  • Number of jobs completed by a service engineer
  • Tonnes of goods delivered for a long-distance heavy goods vehicle
  • Number of cases delivered for a multi-drop delivery vehicle
  • Number of passengers carried

At this early stage it may not be possible to complete this step and develop an Energy Efficiency measure, but these figures will inform your business case for change.

Check for consistency, cross check reported mileages

SpeedometerTake a sample of vehicles and physically check their odometer readings against your records.

These readings cannot match the recorded readings exactly, but they may highlight any divergences and inconsistencies in your reporting.

The objective of this step is to ensure your reporting systems are sufficiently robust to eliminate the need for ongoing vehicle fuel checks.

How will you know when this step is complete

Regardless of the number of vehicles you are running you should now be able to produce a baseline fuel usage report with the total fleet fuel usage figures, as in the example below:

Type of vehicleHGVVanCarCar 
Number of vehicles112053vehicles
Total Annual Mileage1,000,0001,000,000200,000     60,000Km
Fuel type Diesel Diesel Diesel PetrolLitres
Annual fuel usage  400,000   200,00015,660   7,200Litres
Fleet Fuel usage      40.00      20.00      7.83  12.00Litres/100Km
Cost per litre      0.83      0.83      0.83      0.87excl. VAT
Annual Cost€ 332,000€ 166,000   12,998     6,278excl. VAT
Environmental Impact         1,0525264117tonnes CO2
Savings value @10%  33,200   16,600    1,300      628excl. VAT

You can derive CO2 output by multiplying the litres used by a constant;

  • 2.63Kg of CO2 per Litre of diesel
  • 2.30Kg of CO2 per litre of petrol

If only total monetary values are easily obtainable, use AA historic prices for period to derive approximate volume usages.

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