The Resurgence Carbon Dioxide Calculator

The Resurgence Calculator:

• came first in an independent survey of carbon calculators on-line
• is widely recognised as the most user-friendly and accurate on-line carbon calculator
• is often the single calculator referred to in articles on carbon footprinting

You can use the full calculator below to:

• Easily and accurately calculate your carbon footprint
• See which areas of your lifestyle allow the easiest CO2 savings
• Monitor your CO2 emissions from year to year
• Enjoy the feel good factor of knowing how much CO2 you have saved

This is the accurate calculator which requires your domestic energy bills and MOT certificate. If you do not have access to these, select the quick calculator.

To use the calculator on-screen

Simply fill in the forms with your figures. The figures will automatically update as you proceed, including the the grand total table at the end of this page.

Online Carbon Calculator

Home

Details

First enter the number of persons in your home, counting 1 for each adult and 0.5 for each child under 12

Number of persons in your home

Enter the year for which you are making the calculation

Carbon Calculation for Year

Enter your name

Name

Electricity

On your electricity bills you will find the number of “units” you have used for each quarter, measured in kilo-Watt-hours (kWh). Enter these into the table below.

If you have an electricity meter, enter the amount of money you put into it each week, on average. The table will multiply by 52 to get the cost per year, and then divide this by the average cost per unit (on average 14p per kWh in 2008) to end up with the number of units used per year.

Type of electricity tariff?

100% Green

Electricity completely from renewables

30% Green

Electricity partly from renewables

Normal Tariff

Electricity Bills

	Units (kWh)
First Quarter
Second Quarter
Third Quarter
Fourth Quarter
Totals Units per year	kWh
Conversion Factor
Total CO2 emissions	kg

Electricty Meter

Average cost per week
Cost per year	£
Cost per unit	£
Units per year	kWh
Conversion Factor
Total CO2 emissions	kg

CO2 Emissions 0kg

No. persons in home

Personal share 0kg

(Note 4)

Gas

Piped Gas

Piped gas is normally “natural gas”. Gas bills tell you how much gas you have used in kWh, therms, or cubic metres. Enter one of these into the table below (do not double account - use only one column). Gas delivered to a bulk storage tank is normally liquid propane gas, which is a type of liquid petroleum gas or LPG. The bill should quantify your use in litres. Enter this into the table.

Alternatively if you pay a regular monthly amount enter details in the Monthly Spending table.

Gas Bills

	LPG	Natural Gas
	litres	kWh	Therms	Cubic m
Bill One
Bill Two
Bill Three
Bill Four
Bill Five
Bill Six
Total/year
CO2 factor
CO2 Ems

Monthly Payment

Amount
£ per unit
Units
Factor
CO2

(Note 5)

Bottled Gas

Bottled gas comes in two different types: Butane, in blue bottles, and Propane, in red bottles. (These are both types of liquid petroleum gas or LPG.) The contents of the bottles are quantified by weight. Butane comes in 4.5kg, 7.0kg and 15.0kg bottles. Propane comes in 3.9kg, 6.0kg, 13.0kg and 19.5kg bottles. Enter the bottle size and the number of bottles you use per year into the relevant column of the table below.

	Butane	Propane
Bottle Weight	4.5kg 7.0kg 15.0kg	3.9kg 6.0kg 13.0kg 19.5kg
No. bottles per year
Total weight
Litres per kg	1.74	1.95
total no. litres
Conversion factor
CO2 emissions

Total Gas CO2 emissions 0kg

No. persons in home

Personal Gas CO2 emissions 0kg

Oil

Oil is billed per litre. Enter the number of litres for each bill in the table below.

Oil Bills

	litres
Bill One
Bill Two
Bill Three
Bill Four
Bill Five
Bill Six
Total per year
Conversion
CO2

Total Oil CO2 emissions 0kg

No. persons in home

Personal oil CO2 share 0kg

(Note 6)

Coal

Coal usage per year

Coal is either billed per kg or per bag, bags usually being 25kg. Enter the number of bags per order. The calculator is set at 25kg per bag, but if you have different weight bags you can overwrite this.

	No. bags	kg/bag	Total kg
Bill One
Bill Two
Bill Three
Bill Four
Bill Five
Bill Six
Total kg per year
Conversion factor
CO2 emissions

Total Coal CO2 emissions 0kg

No. persons in home

Personal Coal CO2 share 0kg

Wood

Firewood usage

Like all fuels, wood is essentially carbon. Burning it emits carbon dioxide, and growing it absorbs carbon dioxide. A new tree absorbs the carbon dioxide emitted by burning an old tree. But there is a time delay of 25-50 years. Given that we need to reduce global CO2 emissions in the next 10-20 years, this time delay for re-absorption is too long. Therefore in this calculator wood is not considered carbon neutral, but you are only “charged” for half the emissions produced by burning it.

If you procure wood by the tonne or kg, enter the figures in the table below. (1 tonne = 1,000 kg.. If you obtain wood by the “load” and the weight is not known, it is possible to estimate your usage. I would guess that an average stove or Rayburn uses 10kg of wood in an evening or half a day. If you run your stove every evening for half the year (180 evenings), you burn 1,800kg per year. Using this as a benchmark, estimate your wood use and fill in the table.

	kg
kg used per day
Days use per year
Total kg used per year
Conversion factor
CO2 emissions
Half charge

Total Wood CO2 emissions 0kg

No. persons in home

Personal Wood CO2 0kg

(Note 7)

Transport

Car

First select the type of car you have from the list.

From your last and previous MOT certificates enter the recorded mileages into the table below. The table will subtract the previous from the last to give you last year’s mileage. Make a guess at your “share” of the car’s use, and enter this in the table below, as a decimal. For example if you are the sole user of the car, enter your “share” as 1. If your share is 50%, enter 0.5; for one third enter 0.33, for 25% enter 0.25, etc.

If you have an electric car and your charging comes under your electricity bills at home don’t enter its mileage in the table below or it will be covered twice. If it is not covered or if you charge it elsewhere, you can either record the kWhs and add these to the house electricity section, or enter your mileage in the table below.

If you hire or borrow a car but do not own one you can list your car journeys in the next section under car and taxi journeys.

	Primary Car	2nd Car
Car type (Note 8)	Petrol Medium Hybrid Petrol Mini Petrol Supermini Petrol Lower Medium Petrol Upper Medium Petrol Large Hybrid Petrol Van to 1.3 tonne Petrol MPV Petrol Executive Petrol Sports Petrol Duel Purpose 4x4 Petrol Luxury Diesel Mini Diesel Supermini Diesel Lower Medium Diesel Upper Medium Diesel MPV Diesel Executive Diesel Sports Diesel Duel Purpose 4x4 Diesel Van to 3.5 tonne Diesel Luxury LPG/CNG Medium LPG/CNG Large Electric Small Electric Medium Electric Large	Petrol Medium Hybrid Petrol Mini Petrol Supermini Petrol Lower Medium Petrol Upper Medium Petrol Large Hybrid Petrol Van to 1.3 tonne Petrol MPV Petrol Executive Petrol Sports Petrol Duel Purpose 4x4 Petrol Luxury Diesel Mini Diesel Supermini Diesel Lower Medium Diesel Upper Medium Diesel MPV Diesel Executive Diesel Sports Diesel Duel Purpose 4x4 Diesel Van to 3.5 tonne Diesel Luxury LPG/CNG Medium LPG/CNG Large Electric Small Electric Medium Electric Large
I use the following proportion of bio diesel (Note 9)	Never 25% 50% 75% 100%	Never 25% 50% 75% 100%
Last MOT mileage
Previous MOT Mileage
Last year's mileage
CO2 per mile
Fuel CO2 emissions
My car is less than 14 years old (Note 10)
Manufacturing CO2
Annual share (14 yr life)
TOTAL ANNUAL CAR CO2
My Share of its use
Personal CO2

Personal annual car CO2 0kg

Motorcycle

Motorcycle Size	Small Medium Large
Last MOT mileage
Previous MOT Mileage
Last year's mileage
CO2 per mile
CO2 emissions
My motorcycle is less than 14 years old (Note 10)
Manufacturing CO2
Annual share (14 yr life)
TOTAL ANNUAL MOTORCYCLE CO2
My Share of its use
Personal CO2

Personal annual motorcycle CO2 0kg

(Note 11)

Journeys

You can use the following table to list your journeys made in the last year in addition to your car use. Enter the distance (or journey-time for international rail and flights), select the single or return, the number of people who share the journey (for car/taxi journey) and the frequency with which you make the journey. The table has room for 5 journey listings under each section. If you need more space, simply list your journeys on a separate sheet of paper, add up the miles, and enter them into the table.

To help estimate journey distances you can use the Google distance calculator at http://www.daftlogic.com/projects-google-maps-distance-calculator.htm. For road distances multiply the geographical distance by 1.5, for rail distances multiply by 1.2, for air distances multiply by 1.1 and for sea distances use the geographical distance.

Hire Car, Taxi, Occasional Car Use

Journey Description	Distance (miles)	Return?	Frequency Times per	Persons aboard	Total miles
		one way two way	week month year	1 2 3 4 5
		one way two way	week month year	1 2 3 4 5
		one way two way	week month year	1 2 3 4 5
		one way two way	week month year	1 2 3 4 5
		one way two way	week month year	1 2 3 4 5
Total
Conversion factor for kg CO2 per mile
CO2 emissions (kg)

CO2 Emissions 0kg

Bus

Journey Description	Distance (miles)	Return?	Frequency Times per	Total miles
		one way two way	week month year
		one way two way	week month year
		one way two way	week month year
		one way two way	week month year
		one way two way	week month year
Total
Conversion factor
CO2 emissions (kg)

CO2 Emissions 0kg

Coach

Journey Description	Distance (miles)	Return?	Frequency Times per	Total miles
		one way two way	week month year
		one way two way	week month year
		one way two way	week month year
		one way two way	week month year
		one way two way	week month year
Total
Conversion factor
CO2 emissions (kg)

CO2 Emissions 0kg

Ferry

Journey Description	Distance (miles)	Return?	Frequency Times per	Total miles
		one way two way	week month year
		one way two way	week month year
		one way two way	week month year
		one way two way	week month year
		one way two way	week month year
Total
Conversion factor
CO2 emissions (kg)

CO2 Emissions 0kg

National Rail

Journey Description	Distance (miles)	Return?	Frequency Times per	Total miles
		one way two way	week month year
		one way two way	week month year
		one way two way	week month year
		one way two way	week month year
		one way two way	week month year
Total
Conversion factor
CO2 emissions (kg)

CO2 Emissions 0kg

International Rail

Journey Description	Time (hr)	Distance	Return?	Times per year	Total miles
			one way two way
			one way two way
			one way two way
			one way two way
			one way two way
Total
Conversion factor
CO2 emissions (kg)

CO2 Emissions 0kg

Domestic Flights (0 - 300 miles)

Journey Description	Time (hr)	Distance	Return?	Times per year	Total miles	Conversion (RFI* = 2)	Carbon Emissions (kg)
			one way two way
			one way two way
			one way two way
			one way two way
			one way two way
Total

CO2 Emissions 0kg

Short Haul Flights (300 - 2,000 miles)

Journey Description	Time (hr)	Distance	Return?	Times per year	Class	Total miles	Conversion (RFI = 3)	Carbon Emissions (kg)
			one way two way		Economy Premium
			one way two way		Economy Premium
			one way two way		Economy Premium
			one way two way		Economy Premium
			one way two way		Economy Premium
Total

CO2 Emissions 0kg

Long Haul Flights (2,000 miles +)

Journey Description	Time (hr)	Distance	Return?	Times per year	Class	Total miles	Conversion (RFI = 3)	Carbon Emissions (kg)
			one way two way		Economy Premium Business 1st Class
			one way two way		Economy Premium Business 1st Class
			one way two way		Economy Premium Business 1st Class
			one way two way		Economy Premium Business 1st Class
			one way two way		Economy Premium Business 1st Class
Total

CO2 Emissions 0kg

^* This calculator uses an RFI (Radiative Forcing Index) of 2 for domestic flights and 3 for short and long haul flights, meaning that the actual CO2 emissions are multiplied by 2 or 3 to account for their global warming effect at high altitude. (Note 12)

Food

Here are some simple questions on diet and food sourcing. Tick the category that applies best to you.

Diet

I eat meat, fish, eggs and dairy products:

Very often

(meat around twice a day)

Quite often

(meat once a day, eggs/dairy often)

Not often

(meat rarely or vegetarian)

Never

(vegan)

CO2 Emissions 0kg

(Note 13)

Sourcing

My food shopping is best described by:

I buy fresh food from the supermarket, and don’t check the labels to see where it’s from. I buy lots of packaged and convenience food.
I buy most shopping from the supermarket, and some from local markets.
I buy mostly seasonal organic produce, and few tinned or processed foods.
I only buy local, organic, seasonal foods, grow some fruit and veg, and eat very few packaged items.

CO2 Emissions 0kg

Leisure

Fuel Intensive Activities

This table gives you a chance to estimate your carbon dioxide emissions specifically from leisure activities that use fossil fuels, such as motor-boating, jet-skiing, flying and motor racing. Columns are given for petrol, diesel, kerosene (aircraft fuel) and bio-diesel. As the possibilities and patterns of use are so variable, it is necessary for you to work out your rough fuel usage per year, then enter this into the table below.

Activity Description	Litres of Fuel	Fuel Type	Times per year	Total litres	Conversion Factor	CO2 emissions
		Petrol Diesel Kerosene Bio-diesel
		Petrol Diesel Kerosene Bio-diesel
		Petrol Diesel Kerosene Bio-diesel
		Petrol Diesel Kerosene Bio-diesel
		Petrol Diesel Kerosene Bio-diesel
		Petrol Diesel Kerosene Bio-diesel

CO2 Emissions 0kg

Industry Share

National Share

This is our share in maintaining national infrastructure and services including, roads, utilities, government, health, defence and education.

CO2 Emissions 1 tonne (1000kg) per person per year

Spending Habits

The table below starts with a base share of 1 tonne CO2 per person per year as our share of the national infrastructure and services that we all benefit from.

The remaining 2.5 tonnes of industrial CO2 emissions is then calculated in relation to income. This is due to the fact that most products and services in the UK use fossil fuels, and therefore the correlation between income (or more precisely expenditure) and emissions may be surprisingly close. (Note 14)

Enter a figure for the income-related share as 1 tonne per £10,000 of total household income. (E.g. For a household income of £35,000 enter 3.5 tonnes.) Below that appears the number of people in the home and the resulting income-related share per person.

Using the income related share per person as a guide, enter a new figure of your own choice for "Adjusted Income Related Share". This can be based on the following criteria:

If you buy hand-made, second-hand, locally-produced, low-energy, un-mechanised products, and repair rather than replace items, this will reduce CO2 emissions. If you earn a lot of money but spend little of it, or live almost entirely from the land, this will reduce CO2 emissions. With considerable thought and effort you may reduce your income-related emissions by as much as half. This part of the calculator is obviously approximate, therefore please make the estimation you feel happy with. The aim of the calculator is to aid in reducing emissions. Simply being aware of CO2 factors associated with industrial products should help toward this end.

Base Share

Base Tonnes

  Enter 1 tonne per £10,000 of household income

My spending on products and services can be described as:

Very carbon conscious: I buy hand-made, second-hand, locally-produced, low-energy, unmechanised products, and repair rather than replace items.
Carbon conscious: I take an interest and chose low carbon options where possible.
Average: I am aware of carbon issues but not always sure which choices are best.
Not very carbon conscious: Carbon issues have no affect on my purchase habits.

CO2 Emissions 0kg

No. persons in home

Personal share 0kg

Summary

Total Personal CO2 Emissions

	CO2 (kg)	%
Home
Transport
Food
Leisure
Industry Share
Grand Total

Details

Home

	CO2 (kg)	%
Electricity
Gas
Oil
Coal
Wood
Home Total
Personal Share

Transport

	CO2 (kg)	%
Car One
Car Two
Motorbike
Other Car Journeys and Taxi
Bus
Coach
Ferry
National Rail
International Rail
Domestic Flights
Short Haul Flights
Long Haul Flights
Transport Total

Food

	CO2 (kg)	%
Diet
Sourcing
Food Total

Industry

	CO2 (kg)	%
National Share
Spending Habits
Industry Total
Personal Share

Here you have it. Your personal annual CO2 emissions. Approximately. To put this in context, national average emissions are 10 tonnes per person per year. In 2004 the UK government pledged to cut emissions by 20% by 2012 to around 8 tonnes per capita. They have now pledged 80% reductions by 2050 to around 2 tonnes per capita, which is the sustainable CO2 quota per global capita.

If you wish to reduce your CO2 emissions a good target is 4% per year. This is a pleasantly easy target, is in line with UK Government National Indicator Targets, and if everyone did it, would reduce CO2 emissions by 80% by 2030.

If you would like tips on the easiest ways to reduce your carbon footprint, you can download my short booklet The Guide to Low Carbon Lifestyles. It shows how low carbon choices are easy and fun and enhance your quality of life.

I hope you enjoyed the calculator.

With best wishes,

Mukti Mitchell

North Devon, October 2009

Sources include

• The Department for the Environment, Food and Rural Affairs
• The National Energy Foundation
• The National Office of Statistics

Mukti Mitchell

Mukti Mitchell is a carpenter, sailor, author and director of CosyHome Company, which provides insulation solutions for period properties in the South West of England. He designed the Explorer zero-emission microyacht and sailed around Britain in 2007 to promote low carbon lifestyles.

METHODOLOGY NOTES

Note 0. Principle Data Sources

The principal source of data for this calculator is the "Guidelines to DEFRA’s Greenhouse Gas (GHG) Conversion Factors for Company Reporting - Annexes" .

Another useful source of GHG conversion factors is the "Inventory of Carbon and Energy (ICE)" from The University of Bath.

Further figures and methodology notes on the different sections of the Resurgence Carbon Calculator follow below.

Note 1. Personal and Work Emissions

It is not necessary to include work emissions in your personal carbon emissions calculation. This is because every product and service has an end user. For example if you work for an iron smelting company and have to fly abroad regularly for board meetings, your flight emissions will be included in the company’s total CO2 emissions. This total will be divided by the number of tonnes of iron produced by the company per year resulting in an associated "CO2 ticket" per tonne of iron. This ticket will be passed to the purchasers of the iron, for example a car manufacturer. The car manufacturer will add this CO2 ticket to the company’s total CO2 emission and divide this by the number of cars manufactured. The final resulting CO2 ticket for the cars sold will be passed to the customer to be included in their personal annual CO2 calculations. All government related activities are covered by the 1 tonne base industry share per person per year which appears in the last section of the calculator.

2. Carbon and Carbon Dioxide

When one carbon atom combines with two oxygen atoms this becomes carbon dioxide. 1kg of carbon combines with 2.667kg of oxygen to produce 3.667kg of carbon dioxide.

3. Green Tariffs

100% green tariffs source all electricity from renewables such as wind, solar and wave power. Because it takes some fossil fuels to build the renewable generators, this is given a CO2 output of 5% of non-renewable sources.

Semi-green tariffs like Ecotricity’s New Energy tariff source around 30% from renewables and the rest from normal sources (2008). Normal Tariffs source 1% from renewables, which is taken into account in the conversion factor.

4. Electricity

In November 08:

Based on £20/month: EDF 18p/kwh, British Gas 8p, E.on 20p, average 14p (includes standing charges).
Based on £40/month: EDF 15p, BG 10p, Good Energy 18p, Av 14p.
Based on £80/month: EDF 14p, BG 10p, GE 18p, Av 14p

5. Gas

In November 2008:

Postcode EX39: Npower 3.6p/kWh, E.on 5.7p, Av 4.7p
Postcode NW5: Ebico 3.8p, Npower 6.2p, Av 5p

Natural Gas CO2 emissions: 0.206kg/kWh (Defra 2008)
1 Therm = 96.7cuft natural gas
1m3 = 35.3 cu ft :: 1 therm = 2.74cu m
(:: means therefore)

6. Coal

CO2 to energy ratio for coal is 0.313kg CO2 per kWh.

7. Wood

Recent studies show that old growth forests continue to absorb CO2 at rates nearly as fast as new growth forests for hundreds of years. Cutting forests and disturbing soils causes and involves high CO2 release and only a small proportion of wood ends up in permanent use not returning CO2 to the atmosphere. In the light of these studies the Resurgence Carbon Calculator takes the view that forest management is not carbon neutral, and and we need to leave old forests uncut to allow them to sequester CO2.

References:

"Old-growth forests as global carbon sinks". Nature 455: 213-215. Nov 2008. "Forests that are 200 years old or older continue to sequester an estimated 8.8 tonnes CO2 per hectare per year." - Recent study of real world data from 519 forests by Luyssaert, S., Schulze, E.-D., Borner, A., Knohl, A., Hessenmoller, D., Law, B.E., Ciais, P. and Grace, J. 2008.

"Energy forests with Salix as a Carbon Dioxide sink" By Veli Pohjonen. This recent study of new willow forests in Finland shows sequestering of 11.6 Tonnes CO2 per year.

Wood technical data from the Biomass Energy Foundation (BEF) Energy 19.75MJ/kg. 1kWh = 0.2778 MJ. :: Wood = 5.49kWh/kg Energy 13.9GJ/M3 = 13.9MJ/l = 3.86kWh/l :: Wood pellets have density of 0.703kg/l CO2 Ems 90kg/GJ = 0.09kg/MJ = 0.324kg CO2 per kWh (Roughly 50 per cent of dry woody biomass is in elementary carbon) (:: means therefore)

8. Electric Car Emissions

Tesla 110Whrs per km = 176Whrs per mile = 0.08kg CO2 per mile. Wrightspeed equivalent to 170mpg = 0.06kg CO2 per mile. Typical Californian EV does 140 mile on one charge of 25kWh = 2/3 Gal petrol equivalent = 0.18kWh per mile = 0.08kg CO2 per mile. Converted electric Geo Prism 12 kWh for 50 miles = 0.24kWh per mile = 0.10kg CO2 per mile

9. Biodiesel

In this calculator biofuels are given a "half charge" of CO2 compared to their fossil fuel counterparts. This is because biofuels emit as much CO2 as their fossil fuel counterparts but as new plants are growing in their place some of this CO2 is re-absorbed. However bio-fuels occupy agricultural land that is needed for food. And rainforests have been destroyed to grow bio-fuels, reducing carbon sequestration. Therefore it appears that bio-fuels are only sustainable if they make up a small part of the overall energy mix. Hence this calculator gives them a "half charge" for their CO2 emissions.

10. Car Manufacturing Emissions

According to research by Ford (1995) manufacturing a car emits approximately the same CO2 as 1.4 years of average use for that type of car.

The Commission for Integrated Transport gives an average lifespan of 14 years for UK cars, with an average annual mileage of 10,000 miles.

11. Motorcycle

Manufacturing CO2 for motorcycles is taken by weight proportional to cars. Average car weightt = 1400kg, average motorcycle weight = 200kg. Therefore average motorcycle weight = 15% of average car weight.

12. Air Travel

RFI stands for Radiative Forcing Index. This is a factor for the increased global warming effect of green house gases emitted at high altitude.

Domestic Flights spend less time at high altitude and therefore the Resurgence Carbon Calculator uses an RFI of 2.0. For Short and Long Haul Flights the RCC uses and RFI of 3.0.

The Intergovernmental Panel on Climate Change (IPCC) gives an RFI for air travel as 2.7 in 1992 and ranging from 2.2 to 3.4 for the year 2050 depending on various different scenarios. As the science of Radiative Forcing is new and uncertain and the IPCC has stated that it could be as high as 15 the Resurgence Carbon Calculator uses an RFI of 3 for high altitude flights.

13. Food

This easy reference guide for food related CO2 emissions by diet and shopping habits is based on a study from Readers Digest Magazine.

14. Income Related Share

The National Energy Foundation states that “around of half UK CO2 emissions come from industry and commerce supporting our everyday lifestyle” www.natenergy.org.uk/co2mment.htm

This means producing our food, clothes, consumables, and maintaining our national infrastructure. National average annual CO2 emissions per capita are 10 tonnes, so our average “industry and commerce emissions share” is 5 tonnes each.

Part of industry and commerce provides infrastructure and resources that benefit everyone, and part of it provides the goods of “consumerism”. We may all take a share of the CO2 produced by the former, and the latter can be shared out according to consumption, which is largely linked to income. Public services and essential industries including health, education, defence, agriculture and construction produce 23% of industry and commerce CO2 emissions. “Domestic consumption” including cars, recreation, electrical goods, clothing, and consumables account for 40% of industry and commerce emissions. “Trade” including wholesale, garages, showrooms and computer activities accounts for 7%. And heavy industry, including mining and the material production, accounts for 30%.

To estimate our personal share of industrial emissions we begin with a base of 1 tonne per person towards the public and common amenities that nearly everyone benefits from. Food and car manufacturing emissions are accounted for in previous sections of the calculator and have an average output of a further 1.5 tonnes per person per year. This leaves 2.5 tonnes from the industry share to be accounted for by income-related calculations. The UK average wage is £25,000 per year, and the income per capita is also around £25,000 per year. This results in an income-related share of 1 tonne per £10,000 of income.