Carbon Footprint Calculator FAQs

Different transport modes can have a large influence on the overall carbon emissions. For example air-freighting cargo can emit up to 100 times more CO₂ than shipping it by sea.

Why select different vehicle types?

Even within a single transport mode such as ‘road’ there can be as much as a seven-fold difference in carbon emissions between different types of vehicle. In general a larger vehicle will be more efficient in transporting goods than a smaller one, provided the vehicle’s capacity can be filled.

What if I don’t know which city I am sourcing from?

The select city function allows users to specify an extra level of detail when calculating their CO₂ footprint. However, if you do not know the specific city, the calculator will default to the capital city of the country selected.

I can’t find my city in the drop down list?

If you know the specific source or destination city, but cannot find it in the drop down list, you can either select the closest city available or specify the exact distance travelled yourself using the specify distance option.

I can’t find my port in the drop down list?

This calculator contains 80 of the world’s largest ports and these ports should satisfy most shipping requirements. However, not every country is allocated its own port and occasionally the calculator must default to the nearest large port, even if this is in another country. If you would like to calculate the distance from a port not listed – please estimate it yourself and enter the distance using the specify distance form.

What is RFI and should I include it?

As well as the CO₂ emitted whilst flying, there are other compounds emitted whilst flying (e.g. NOx) that contribute to global warming. Ticking the RFI box will include the global warming impact of these non-CO₂ emissions.

The UK Government Department DEFRA has recommended that RFI is included for the purposes of carbon foot-printing.

Why do I need to enter the weight of my shipment?

The weight of a shipment is required to calculate the CO₂ emitted – in general a heavier plane, train, lorry or ship will burn more fuel than a lighter one, and thus emit more CO₂.

How is the distance calculated?

For the distance between cities on the globe is calculated from their co-ordinates and then scaled by an indirect factor, dependent on transport type, representing the non-linearity of transport systems.

How are the emissions calculated?

The UK government department DEFRA provides guideline CO₂ emission factors for each transport mode for each tonne-km travelled. The CO₂ emissions for the selected transport mode are calculated by multiplying the appropriate emission factor by distance travelled and the shipment weight to give an estimate of the CO₂ emitted for the journey.

What if my journey comprises multiple stages, each with different modes of transport?

You can add as many stages to your journey as you wish – and you can specify a different transport mode each stage. To add another stage, click the “Add Stage” button.

What do these gauge meters display?

These gauges give a graphical representation of the Tonnes of CO₂ per kilometre. The top of the gauge is 1.3 Tonnes of CO₂ per kilometre, and the bottom of the gauge is 0.01 Tonnes of CO₂ per kilometre.

Why does the "Shipment details" section disappear after the first stage is calculated?

The weight and value of a shipment are constants throughout the journey, therefore they can only be set at the beginning of the journey. Expand stage 1 and you will be able to edit these values.

Why has Google Maps not plotted my route?

If you have specified the distance instead of setting a Start and Finish location, the calculator has no visibility of the beginning or end of the journey and will therefore be unable to plot a route. Alternatively, if you have added a new stage after the initial journey was calculated and the 'Start' location does not match the previous 'Finish' location, the route has effectively been broken.

Why is GDP per Capita in USD?

To make the GDPs more accessible and comparable they are all given in USD.

Social Welfare Calculator

How are the social welfare benefits calculated?

The Sequoia Partnership have used the United Nations Human Development report to examine the link between GDP growth and social welfare. The UN’s human development report publishes social welfare indicators for over 190 countries and includes indicators such as the percentage of a population who are living on less than $2 per day.

The link between GDP growth and each of the human development indicators allows us to estimate the percentage improvement for each indicator arising from the incremental increase in GDP from overseas procurement contracts.

The relationships are generated for each indicator independently of the other indicators.

How do you calculate the number of people affected?

This is best illustrated by an example: if we calculate that a GDP increase of $10 million is likely to lead to an additional 1% of population having access to an improved water source, then to calculate the number of people that represents, we simply multiply 1% by the country’s population.

Are the same people included more than once, under different indicators?

Almost certainly. The calculations for the number of people affected for each indicator are done independently of the other indicators – so the calculation of the number of additional people enrolled in secondary education takes no account of the number of additional people with adequate nutrition. It seems highly likely that there would be overlap between these two groups of people.

Why is value important?

The value of an overseas procurement contract is used to work out the incremental increase in a country’s GDP. The calculator uses the increase in GDP to estimates the corresponding improvement in the Human Development Indicator.

Why can’t I see all of the social measures for this country?

The social welfare benefits are calculated using data from the United Nation’s Human Development Report. Unfortunately, data is not available for every country for every social welfare indicator and so is missing from the report – this means, for a small number of indicators/countries, we are unable to quantify social welfare benefits.

Why is there no change in the social welfare indicators, or only a very small change?

There are a couple of reasons why the social welfare impact of a purchase may be small. For wealthy countries for example, it takes a much larger purchase to impact the social welfare of its population. Often, above a certain GDP, the purchase will make no change whatsoever, and increases to social welfare will be more affected by government policy etc.

Clearly, the size of the social benefit is also proportional to the size of the purchase. If the purchase is of a modest size, the social benefits will also be modest.