GB2470216A - Calculating the carbon footprint for a purchase - Google Patents

Abstract

A method of calculating the carbon footprint associated with a purchase transaction, such as fuel, petrol or airline ticket, comprising obtaining transaction details comprising at least an identification of the merchant, and the amount of the transaction. According to the method the transaction details are mined for secondary data, such as method of payment or amount of gasoline bought, that can be used for refining the carbon footprint calculation. If no secondary data are available the carbon footprint calculation is based on a merchant category code and the transaction amount.

Description

IMPROVED SYSTEM AND METHOD FOR DETERMINING TRANSACTION-

RELATED GREEN HOUSE GAS EMISSIONS

BACKGROUND OF THE INVENTION

1. Field of the Invention

[0001] The invention relates generally to an improved system and method for determining the estimated green house gas emissions associated with the purchase of goods or services, and more particularly to such a system and method for transactions involving the use of a credit card or other type of payment card.

2. Description of the Related Art

[0002] As climate change has come to the forefront of public awareness, there is a growing interest on the part of individual consumers in developing an assessment of the environmental impact of their purchases, and in making contributions towards initiatives aimed at off-setting greenhouse gas emissions associated with their purchases. Systems and methods have been suggested aimed at addressing these consumer interests.

[0003] US Patent Application Publication 2006/0089851 to Silby et al. discloses a method for providing a consumer with credit card statements containing carbon emission estimates associated with specific items on the statement. The system identifies items on the financial statements for which a relationship exists with a quantifiable quality-related characteristic, such as carbon emission. The reference does not explain what item details are required for the system to make this determination, or how such details are provided to the financial system.

[0004] US Patent 7,426,489 B2 to Van Soestberg discloses a method for trading carbon credits. As part of the method, the carbon emissions associated with certain consumer activities, such as driving a car. The method requires extensive data input on the part of the consumer. The extensive data input requirement limits the use of the disclosed method to a small minority of highly dedicated consumers.

[0005] US Patent Application Publication 2006/00953 56 to Koornstra proposes a system and method that eliminates the need for extensive data input. The disclosed system uses manufacturer category codes to estimate the emission value of a transaction. Although readily implementable using existing monetary transaction infrastructure, the method provides rather crude approximations and may yield anomalous results.

[0006] WO 2007/079228 to Redefining Progress discloses a method for associating a greenhouse gas value to a transaction. The method is referred to as the "minable purchase method", and requires a detailed description of the item and quantity purchased.

[0007] Thus, there is a need for an improved system and method for determining transaction-related greenhouse emissions. There is a particular need for such a system which does not impose a disproportionate data input burden on its users, and which can be used even when no detailed description of a purchased item is generated.

BRIEF SUMMARY OF THE INVENTION

[0008] The present invention addresses these problems by providing a method for determining a carbon footprint of a transaction, said method comprising the steps of (i) obtaining transaction details comprising at least primary transaction data consisting of a transaction amount and an identification of the merchant; (ii) mining the transaction details for secondary transaction data suitable for refining the carbon footprint calculation; (iii) calculating the carbon footprint using the secondary transaction data or, if such secondary transaction data are unavailable, using the merchant identification and the amount of the transaction.

[0009] Another aspect of the invention comprises a system for implementing the method.

The system comprises: (i) a means for collecting and/or generating transaction details associated with a purchase transaction, said transaction details comprising primary transaction data consisting of a merchant identification and a transaction amount; (ii) means for determining an emission category and an emission factor based on the merchant identification; (iii) means for calculating a carbon footprint based on the emission factor and the transaction value; (iv) at least one refinement tool for refining the carbon footprint calculation.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The features and advantages of the invention will be appreciated upon reference to the following drawings, in which: [0011] FIG. 1 is a schematic representation of a prior art system and method.

[0012] FIG. 2 is a schematic representation of an improvement provided by the system and method of the present invention.

[0013] FIG. 3 is a schematic representation of the calculation of an emission value associated with a transaction, according to one embodiment of the invention.

[0014] Fig. 4 is a schematic representation of a method for providing an adjustment based on MCC deviation.

[0015] Fig. 5 is a schematic representation of a method for providing an adjustment based on transaction channel.

[0016] Fig. 6 is a schematic representation of a method for providing an adjustment based on geographic location of the transaction.

[0017] Fig. 7 is a schematic representation of a carbon footprint calculation based on the calculated emission value and possible adjustments.

[0018] Fig. 8 is a schematic representation of a complete system and method according to one embodiment of the invention.

[0019] Figures 9 -12 provide schematic representations of aspects of a second embodiment of the invention.

[0020] Figure 13 provides a schematic representation of the system of the second embodiment.

DETAILED DESCRIPTION OF THE INVENTION

[0021] There is a strong consensus in the scientific community that dramatic changes are taking place in the earth's climate zones. The evidence is overwhelming that human activities involving the combustion of fossil fuels are a major contributing factor to the climate changes.

[0022] There is a growing willingness among the general public to make lifestyle adjustments in order to reduce one's contribution to the emission of green house gases, in particular carbon dioxide, but individual consumers find it difficult to gauge the environmental impact of their actions. Thus, there is a need for reliable feedback to the consumer.

[0023] A truly scientific calculation of the carbon dioxide emissions associated with a particular consumer activity requires a large amount of detailed information. This is the approach taken in US Patent 7,426,489 to Van Soestberg. Although the method proposed in this patent may result in reasonably reliable estimates, the required data input on the part of the consumer is such that only a few highly dedicated individuals will muster the energy and commitment to keep it up. To our knowledge, this method has never been implemented on a meaningful scale.

[0024] US Patent Application Publication 2006/0089851 to Silby et al. seeks to avoid the need for data input by the consumer by providing a method in which items in a financial statement, such as a monthly credit card statement, are analyzed for a potential relationship with a "quantifiable quality-related characteristic", such as carbon emission. The document does not disclose how the financial statement is to be provided with sufficient information on individual items to make such an assessment possible. Moreover, the document does not explain how the correlation between items and emissions is to be made. The stated example refers to comparison with information contained in a database, but the document fails to disclose how such a database is to be created.

[0025] WO 2007/079228 to Redefining Progress proposes a "mineable purchase method", or MPM. The method requires a detailed description of the item and quantity purchased.

These details are contained in what is referred to as the L3 level of credit card transaction information. The document suggests that the method can also be used if only Li or Li and L2 level data are available, but does not explain how this would be possible.

[0026] To the best of our knowledge, neither the method described in US 2006/0089851 nor the one disclosed in WO 2007/079228 has met with practical implementation.

[0027] US Published Patent Application 2006/00953 56 to Koornstra discloses a system and method eliminating the need for extensive data input by using the Manufacturer Category Code (MCC) as the basis for a carbon emission estimate. As the MCC is routinely generated and communicated in standard credit card and debit card transactions, the method does not require any additional data input. The system of Koornstra comprises a database containing groupings of MCCs, with an average carbon emission value per dollar for each grouping. The carbon emission associated with a credit card transaction can be calculated by multiplying the dollar value of the transaction with a factor representing the MCC of the transaction.

[0028] Once the database is established for grouping the MCCs and assigning the carbon emission factor to each grouping, the Koornstra method can be grafted onto an existing credit card transaction infrastructure, without the need for additional data generation or inputting.

Indeed, this method has been successfully implemented in a number of European countries.

[0029] Although effective, the method disclosed in US 2006/0095356 contains a significant weakness. As the estimated carbon emission value is based entirely on the dollar value of the purchase transaction and the MCC of the merchant where the purchase is made, the emission value for a particular product varies from merchant to merchant. For example, a 1 liter bottle of water may represent a low emission value if purchased at a supermarket, and a significantly higher emission value if purchased at a gas station.

[0030] The present invention addresses this problem by providing refinements and improvements to the Koornstra method, while maintaining its essential characteristics of ready implementation.

[0031] The invention will be fully described with reference to a purchase of gasoline. The invention will then be illustrated further with reference to airline and rental car transactions.

It will be understood that the principles described in these examples can be applied to transactions of any type.

[0032] DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

[0033] The following is a description of certain embodiments of the invention, given by way of example only and with reference to the drawings. Referring to FIG. 1, the prior art method of US 2006/00953 56 is schematically represented.

[0034] Transaction details are obtained from a payment card transaction. The term "payment card" refers to any card that can be used for payment of the purchase of a good or service. Examples of a payment card include credit cards, debit cards, ATM cards, bank cards, and the like. Such cards contain a memory medium in which data relating to the card holder and the card holder's account are stored. The memory medium may be a magnetic strip, a chip, and the like. The term "credit card" is used herein to generically describe any type of payment card.

[0035] The transaction details obtained from the transaction include, at a minimum, the dollar value of the transaction, and an identification of the merchant. The merchant identification is used to determine the Merchant Category Code ("MCC"). This aspect is part of a standard credit card transaction. The system of US 2006/0095356 converts the MCC to an Emission Category, from which an Emission Factor is determined from a look-up table.

The Emission Factor is multiplied by the dollar amount of the transaction to provide the CO2 emission, in lbs or kg.

[0036] Figure 2 is a schematic representation of a refinement to the method of US 2006/0095356 in the case of a fuel purchase. This refinement is applicable if the transaction details contain sufficient information to identify the transaction as a fuel purchase. If the transaction details contain sufficient information to determine the amount of fuel of the transaction, the CO2 emission associated with the transaction is calculated directly. If the amount of fuel is not known, the CO2 emission is calculated by multiplying the transaction amount with the Emission Factor, as in Figure 1. Since the transaction has been defined as a fuel transaction, the Emission Factor may be an average Emission Factor for fuel, instead of an average Emission Factor for the MCC.

[0037] Figure 3 shows a schematic representation of a frirther refinement. As in Figure 2, the transaction is identified as a fuel transaction. If fuel details, i.e., the amount of fuel, are available, the CO2 emission is calculated directly. If such details are not available, the fuel price per unit volume (e.g., dollars per gallon, or Euros per liter) is obtained from a fuel price table or feed. The table may be stored in a memory that is part of the system, or may be looked up in real time in a remote database, for example one that is accessible by Internet.

From the transaction value and the fuel price, the amount of fuel in the transaction can be calculated.

[0038] If iieither the amount of fuel nor the average fuel price is known, the standard calculation depicted in Figure 1 is used.

[0039] Figure 4 provides a schematic representation of an adjustment that may be made for a specific MCC. For example, certain merchants have implemented off-set programs to, partially or completely, off-set the carbon emissions associated with the goods or services that they sell. The percentage off-set is reflected in the correction scheme shown in Figure 4.

Basically, the MCC is checked against a look-up table as to whether a correction is applicable. If the answer is "yes", the correction factor is determined, and the correction is applied to the calculation.

[0040] It will be understood that, instead of a downward correction, the calculation may be revised upwardly for merchants who are notoriously inefficient in their energy usage, or who use carbon-heavy resources in their manufacturing, such as coal.

[0041] In a specific embodiment, one or more merchants may maintain a database compiling actual carbon footprints of the products in its inventory. This situation is depicted in Figure 9. The system checks whether the transaction involved a merchant that keeps a database of the carbon footprints of the products that it sells. If the answer is "yes", the system determines the carbon footprint of the transaction based on the items purchased. The necessary product footprint data may be acquired by accessing the database of the merchant in real time. In an alternate embodiment the system comprises a copy of the merchant's database, which is updated on a regular basis, for example daily.

[0042] A similar correction may be applied to reflect the carbon footprint of a specific transaction channel. For example, a transaction by Internet with delivery by parcel service may require the combustion of less fossil fuel than if the same item is purchased by a customer driving a car to a retail store. This correction is reflected in Figure 5. The logic path is similar to that of Figure 4. The system checks whether a correction based on the transaction channel is in order. If the answer is "yes", the correction factor is obtained from a look-up table, and the correction is applied to the calculation.

[0043] The fuel price adjustment shown in Figure 6 is potentially applicable when the fuel price is obtained from a look-up table or an external database. As is well known, fuel prices vary among geographic regions, due to differences in regulatory requirements, taxation, and shipping distances. An average fuel price may be corrected for such variations based on a geographic identifier. The example used in Figure 6 is "zip code", which is the term used in the USA for postal code. It will be understood that other geographic identifiers may be used.

[0044] Figure 7 is a schematic representation of the method for calculating the carbon footprint associated with the transaction. The CO2 emission, which is calculated as described with reference to Figures 2 and 3, is corrected, if at all, with the appropriate adjustments for MCC, transaction channel, and/or geography. It will be understood that further adjustments may be made in a similar manner, as more data become available.

[0045] Figure 8 is a schematic representation of the full carbon footprint calculation for a fuel purchase. It will be understood that the answer to the decision block "Fuel transaction" is "No" if insufficient information is available to identifi the transaction as a fuel transaction, regardless of whether the transaction is a fuel transaction or not. This point illustrates an important aspect of the present invention: the system can be used for any type of transaction, regardless of the amount of information that is available. The minimum information required for the system to work is an identification of the merchant, and the amount of the transaction.

This information will always be available, because it is generated as essential information in any payment card transaction. In other words, the system works for even those transactions that provide the least sophisticated transaction details.

[0046] The system seeks to optimize the calculation of the carbon footprint, and uses three fundamental tools for this task. The first tool scans the available transaction details for information the system can use for refining the carbon footprint calculation. Examples of such information include details identifying the transaction as a fuel transaction, information identifying the geographic location of the transaction, and information identifying the transaction channel.

[0047] The second tool for refinement comprises look-up tables for potential adjustments, such as MCC adjustments, channel adjustments, and the like.

[0048] The third tool for refinements comprises external databases for providing external input. For example, the fuel price table makes it possible to refine the calculation even when the amount of fuel is not provided in the transaction details.

[0049] It will be understood that the system is flexible in terms of its use of external and internal databases. For example, the fuel price table may be an internal database. Such an internal database may be updated by hand on a regular basis, for example once a week or once a day. Or it may be constantly updated by mining data from the Internet, for example by using a web crawler functionality. Or the database may be an external one, being kept up to date by an outside vendor, such as the American Automobile Association (AAA).

[0050] Providers of goods and services are under increasing competitive pressure to reduce the carbon footprint of their goods and services. As companies learn to respond to these pressures, they are becoming more and more willing to provide detailed information on the results of their efforts. As such details become available it is now possible to refine the system further to make adjustments to the carbon footprint calculation on a company-specific basis. The system is well suited for refinements of this kind. This will be illustrated with reference to air travel and car rentals.

[0051] Air travel has been singled out as a major source of carbon emission.

Understandably, a major factor in the calculation of the CO2 emissions associated with an airline trip is the distance traveled. However, there are many additional factors that play a role, and desirably are taken into account when calculating the carbon footprint of the trip.

Such factors include the type of aircraft; the age of the aircraft, newer aircraft being significantly more fuel efficient than older aircraft; the occupancy rate of the aircraft; whether the trip is non-stop, or whether stop-overs are included; and the like. In addition, several airlines now take compensatory measures to reduce their carbon footprint.

[0052] The system of the invention can take these factors into account, in a scheme similar to that shown in Figure 8 for fuel purchases.

[0053] At a fundamental level, the system determines from the available data that the purchase relates to an airline ticket. If no further data are available, the system calculates the carbon footprint based on the dollar amount of the transaction and a factor reflecting an airline industry average carbon emission per dollar. The system will probe the transaction details for information on the specific airline, the aircraft used, etc., and will make appropriate adjustments based on information provided by the airline company or some other source. The mechanism for making such adjustments is similar to that shown in Figure 8.

[0054] Rental car companies provide another example of an industry for which company-specific adjustments can be made. The average fuel consumption of a rental fleet is determined by such factors as the composition of the fleet; the average age of the fleet; the maintenance efforts applied by the rental company, etc. Rental companies are increasingly willing to provide average fleet consumption data to third parties such as credit card issuers.

These data can be used to provide a more refined carbon footprint calculation for the use of rental cars.

[0055] In the case of car rentals there is a risk of double counting. For example, the fuel consumption associated with a car rental can be calculated from the number of miles driven, multiplied by the average fuel consumption for the type of car. If the renter purchases fuel for the rental car using a credit card of the system, the fuel purchase might be added to the calculated consumption of the rental car, and is in effect counted twice. This can be avoided by eliminating from the renter's record all fuel purchases made during the term of the rental agreement. Conversely, the fuel purchases can be used for determining the actual fuel consumption, eliminating the need for making an estimate based on the miles driven.

[0056] Figures 10 -13 depict an alternate, and preferred, system and method for determining a carbon footprint associated with a purchase transaction.

[0057] As shown in Figure 10, the system checks whether the purchase transaction is a fuel transaction or, put differently, whether the transaction details contain enough information for the transaction to be identified as a purchase transaction. If the answer is "no", the calculation proceeds as described above for non-fuel transactions. If the answer is "yes", the system checks whether fuel details are available to permit a direct calculation of the CO2 emission. If this direct calculation is not possible the next level of system preference is a calculation based on the fuel price. If this calculation is also not possible, the fall-back is the standard calculation based on the emission category.

[0058] The refinement shown in Figure 11 addresses price differences between individual states and countries. The refinement shown in Figure 11 applies to transactions that are not fuel transactions. A similar refinement for fuel transactions is discussed below with reference to Figure 12.

[0059] As shown in Figure 11, the system comprises a country-or state percentage table, reflecting price differences between states or countries resulting from such factors as sales tax rates, the level of price competition, shipping distances, the regulatory environment, and the like. The table may be resident in the system, in which case it is updated on a regular basis. In an alternate embodiment the table is accessed in real time at a remote location, for example via the Internet. The table is used to determine a country-or state adjustment.

[0060] Fuel prices are particularly sensitive to geographic differences. Since fuel purchases in general represent a major portion of a person's carbon footprint, it is desirable to correct fuel purchases for geographic differences. It will be understood that such a correction is not necessary if the CO2 emission can be calculated directly from available fuel details, or if fuel prices are available to permit calculation of the CO2 emission based on amount and fuel price (see Figure 10). Figure 12 addresses the situation where insufficient details are available for direct calculations, so that the calculation needs to be based on Emission Category.

[0061] As shown in Figure 12, the system checks the transaction details for the availability of a zip code or an identification of the state or country in which the transaction took place.

The system looks up a fuel percentage from a fuel percentage lookup table. For convenience stores, about 37% of their dollar volume stems from fuel transactions. For gas stations this number is 74%. For the purpose of this calculation the system assumes the purchase to be an average one for the type of merchant. Thus, if the merchant is a convenience store, the system assumes that 37% of the dollar value of the transaction is a fuel purchase, and applies the zip code correction (or the country/state correction) to this portion of the transaction. It will be understood that the fuel factor percentage table is updated on a regular basis.

[0062] Figure 13 depicts the entire system of this preferred embodiment. It incorporates the fuel details analysis of Figure 10; the country/state adjustment of Figure 11; and the fuel percentage adjustment of Figure 12. In addition, this embodiment incorporates the channel adjustment of Figure 4; the MCC adjustment of Figure 5; and a Merchant Number adjustment based on the identity of the merchant. Figure 9 shows a specific embodiment of the Merchant Number adjustment.

[0063] The carbon footprint data calculated by the system can be used in a variety of ways.

[0064] The carbon footprint calculations can be included in the monthly statements issued to the holder of the credit card. This provides the holder with useful information, which can form the basis for making decisions aimed at reducing the individual's carbon footprint.

[0065] Statistical data obtained from a large number of credit card transactions can be used to generate rankings of activities that contribute significantly to an individual consumer's carbon footprint. Statistical data can also be used to generate rankings of companies within a specific industry, such as utilities, airlines, and rental car companies. The effect of such rankings can be reinforced by including suggestions in the card holder's monthly statement, such as "you may be able to reduce your carbon footprint by selecting a different airline in the future; please refer to the airline ranking on our website". A responsible use of this tool may encourage companies to increase their environmental efforts, and to provide reliable data to credit card issuers.

[0066] Another use of the carbon footprint calculations provided by the system and method of the invention is as a basis for providing countermeasures to climate change, Suitable countermeasures include investments in means for capturing and immobilizing carbon dioxide. For example, carbon dioxide may be stored underground in used oil or gas wells, or may be absorbed by growing plants, such as trees. The carbon footprint calculations can be used to provide funding for such projects at a rate proportional to the carbon footprints calculated for an individual's spending. In a preferred embodiment the carbon immobilization effect equals the carbon footprint of the purchase, so that the purchase is carbon neutral. The funding can be provided from the fees levied by credit card companies for the use of a credit card in making a purchase.

[0067] In an alternate embodiment, the carbon footprint calculation is used for purchasing an equivalent amount of carbon credits in the open market. The purchased carbon credits are retired, i.e., they are withdrawn from circulation. This effectively forces industry to reduce its overall carbon emissions.

[0068] Another aspect of the invention is a system for canying out the method. The system comprises a means for collecting and/or generating Transaction Details associated with a purchase transaction, said Transaction Details comprising a merchant identification and a transaction value; means for determining an Emission Category and an Emission Factor based on the merchant identification; means for calculating a carbon dioxide emission based on the Emission Factor and the transaction value, characterized in that the system further comprises at least one refinement tool for refining the carbon dioxide emission calculation.

[0069] The means for collecting and/or generating Transaction Details associated with a purchase transaction can be any device suitable for collecting transaction details. For a point-of-sale ("POS") transaction it may be a credit card reader, coupled to an electronic till for providing the transaction price. For an Internet transaction it may be the Internet server of the merchant, combined with the keyboard of the computer of the customer, in communication with each other via a network. For a cellular phone transaction it can be the keypad of the customer's cellular phone and the server of the merchant, in communication with each other via the cellular phone network.

[0070] As explained herein above, the system of the invention can be grafted onto an existing credit card payment infrastructure, and makes use of certain elements of such existing credit card infrastructure. For example, the means for collecting and/or generating Transaction Details could in large part consist of standard credit card payment tools, which can also be used for payments outside the method of the invention. The credit card itself, however, which is part of the system, would be dedicated to the method of the invention.

[0071] The means for determining an Emission Category and an Emission Factor based on the merchant identification; and the means for calculating a carbon dioxide emission based on the Emission Factor and the transaction value can be standard computer hardware suitably programmed for carrying out the required data handling. These means can be resident in a server, which is in communication with the standard credit card payment system.

[0072] The system further comprises one or more refining tools. A refining tool may comprise a means for mining the transaction details for data other than the merchant identification and the value of the transaction. The merchant identification and the value of the transaction will be referred to as the "primary transaction data", as they constitute the minimum information required for the system to calculate a carbon footprint. Any additional transaction details that can potentially be used for refining the carbon footprint calculation will be referred to as "secondary transaction data". Thus, a refining tool may comprise a means for mining the transaction details for secondary transaction data.

[0073] Examples of secondary transaction data include identification of the item purchased; identification of the quantity of items purchased; the geographic location of the purchase; the date of the purchase; and the like. The means for mining the Transaction Details for secondary transaction data is programmed to look for secondary transaction data that can be used for refining the carbon footprint calculation.

[0074] The refinement tool may further comprise one or more internal databases containing data suitable for refining the carbon footprint calculation. Examples include gasoline prices; carbon emissions associated with the combustion of one gallon of gasoline; carbon emission profiles of specific airline companies; carbon emission profiles of the fleets of specific car rental companies; and the like.

[0075] The refinement tool may further comprise one or more external databases, accessible by the system through a network, such as the World Wide Web. Such external databases may include data on gasoline prices by geography; data on gasoline compositions by geography; up to date load factors of airline companies; up to date age data of rental car fleets; and the like.

[0076] It will be understood that it may be a matter of convenience or cost whether a database of the refinement tool is kept internally or is accessed externally. In general, data that are subject to frequent changes are preferably accessed externally, whereas data that are more permanent in nature may be kept internally.

[0077] Thus, the invention has been described by reference to certain embodiments discussed above. It will be recognized that these embodiments are susceptible to various modifications and alternative forms well known to those of skill in the art. For example, the system may be modified by adding further refinement tools as more relevant data are being made available by manufacturers of goods and by providers of services.

[0078] Many modifications in addition to those described above may be made to the structures and techniques described herein without departing from the spirit and scope of the invention. Accordingly, although specific embodiments have been described, these are examples only and are not limiting upon the scope of the invention.

Claims (27)

1. WHAT IS CLAIMED IS: 1. A method for calculating a carbon footprint associated with a purchase transaction from a merchant, said method comprising the steps of (i) obtaining transaction details comprising at least primary transaction data consisting of a transaction amount and an identification of the merchant; (ii) mining the transaction details for secondary transaction data suitable for refining the carbon footprint calculation; (iii) calculating the carbon footprint using the secondary transaction data or, if such secondary transaction data are unavailable, using the merchant identification and the amount of the transaction.
2. 2. The method of claim 1 wherein the secondary transaction data comprise an identification of the transaction as a purchase of fuel.
3. 3. The method of claim 2 further comprising the step of obtaining a fuel price from a database.
4. 4. The method of claim 3 wherein the fuel price is obtained from an external database, accessed via a network.
5. 5. The method of claim 1 further comprising the step of associating the merchant with a merchant category code, obtaining a deviation value for the merchant category code, and refining the carbon footprint calculation based on the deviation value for the merchant category code.
6. 6. The method of claim 1 wherein the secondary transaction data comprise an identification of a transaction channel, said method comprising the further step of obtaining a deviation value for the transaction channel, and refining the carbon footprint calculation based on the channel deviation value.
7. 7. The method of claim 1 wherein the secondary transaction data comprise an identification of the geographic location of the purchase transaction, said method comprising the further step of obtaining price information specific to the geographic location, and refining the carbon footprint calculation based on the geographic price information.
8. 8. The method of claim 7 wherein the identification of the geographic location comprises a postal code.
9. 9. The method of claim 7 or 8 wherein the purchase transaction comprises the purchase of a ftiel.
10. 10. A method for calculating a carbon footprint associated with a purchase transaction from a merchant, said method comprising the steps of (i) obtaining transaction details comprising at least primary transaction data consisting of a transaction amount and an identification of the merchant; (ii) mining the transaction details for secondary transaction data suitable for refining the carbon footprint calculation, said secondary transaction data being selected from the group consisting of: the item purchased; the quantity purchased; the transaction channel; an identification of the geographic location of the purchase transaction; and a combination thereof; (iii) calculating the carbon footprint using the secondary transaction data.
11. 11. The method of claim 1 or claim 10 wherein the merchant is an airline company, and the carbon footprint calculation is refined based on data specific to the airline company.
12. 12. The method of claim 1 or claim 10 wherein the merchant is a rental car company, and the carbon footprint calculation is refined based on data specific to the rental car company.
13. 13. The method of claim 1 or claim 10 wherein the step of obtaining transaction details comprises obtaining data from a payment card.
14. 14. The method of claim 13 wherein the payment card is a credit card, a debit card, or an ATM card.
15. 15. The method of claim 13 wherein the transaction details comprise an identity of the customer, said method comprising the further step of providing the customer with information pertaining to the carbon footprint of the purchase transaction.
16. 16. The method of claim 1 or claim 10 comprising the further step of determining a carbon compensation amount based on the carbon footprint calculation.
17. 17. The method of claim 16 comprising the frirther step of providing the carbon compensation amount to a carbon offset project.
18. 18. The method of claim 17 wherein the carbon compensation amount is funded by a fee levied by a credit card issuer.
19. 19. A system for calculating a carbon footprint, said system comprising: (i) a means for collecting and/or generating transaction details associated with a purchase transaction, said transaction details comprising primary transaction data consisting of a merchant identification and a transaction amount; (ii) means for determining an emission category and an emission factor based on the merchant identification; (iii) means for calculating a carbon footprint based on the emission factor and the transaction value; (iv) at least one refinement tool for refining the carbon footprint calculation.
20. 20. The system of claim 19 wherein the at least one refinement tool comprises a means for mining the transaction details for secondary transaction data.
21. 21. The system of claim 20 wherein the secondary transaction data comprise an identification of the item purchased; the quantity of items purchased; an identification of the geographic location of the purchase; the date of the purchase; or a combination thereof
22. 22. The system of claim 19 wherein the refinement tool comprises a database containing data suitable for refining the carbon footprint calculation.
23. 23. The system of claim 22 wherein the data relate to gasoline prices; carbon emissions associated with the combustion of gasoline; carbon emission profiles of specific airline companies; carbon emission profiles of the fleets of specific car rental companies; or a combination thereof
24. 24. The system of claim 22 or 23 comprising an internal database.
25. 25. The system of claim 22 or 23 comprising an external database.
26. 26. The system of claim 25 wherein the external database is accessed via a network.
27. 27. The system of claim 26 wherein the network comprises portions of the world wide web.