Carbon footprint

A carbon footprint is historically defined as the total emissions caused by an individual, event, organization, or product, expressed as carbon dioxide equivalent.[1]

In most cases, the total carbon footprint cannot be exactly calculated because of inadequate knowledge of and data about the complex interactions between contributing processes, including the influence of natural processes that store or release carbon dioxide. For this reason, Wright, Kemp, and Williams, have suggested to define the carbon footprint as:

A measure of the total amount of carbon dioxide (CO2) and methane (CH4) emissions of a defined population, system or activity, considering all relevant sources, sinks and storage within the spatial and temporal boundary of the population, system or activity of interest. Calculated as carbon dioxide equivalent using the relevant 100-year global warming potential (GWP100).[2]

Greenhouse gases (GHGs) can be emitted through land clearance and the production and consumption of food, fuels, manufactured goods, materials, wood, roads, buildings, transportation and other services.[3] For simplicity of reporting, it is often expressed in terms of the amount of carbon dioxide, or its equivalent of other GHGs, emitted.

Most of the carbon footprint emissions for the average U.S. household come from "indirect" sources, e.g. fuel burned to produce goods far away from the final consumer. These are distinguished from emissions which come from burning fuel directly in one's car or stove, commonly referred to as "direct" sources of the consumer's carbon footprint.[4]

The concept name of the carbon footprint originates from ecological footprint, discussion,[5] which was developed by William E. Rees and Mathis Wackernagel in the 1990s. This accounting approach compares how much people demand compared to what the planet can renew. This allows to assess the number of "earths" that would be required if everyone on the planet consumed resources at the same level as the person calculating their ecological footprint. The carbon Footprint is one part of the ecological footprint. The carbon part was popularized by a large campaign of BP in 2005.[6] In 2007, carbon footprint was used as a measure of carbon emissions to develop the energy plan for City of Lynnwood, Washington. Carbon footprints are more focused than ecological footprints since they measure merely emissions of gases that cause climate change into the atmosphere.

Carbon footprint is one of a family of footprint indicators, which also includes water footprint and land footprint.

The carbon footprint explained

Measuring carbon footprints

An individual's, nation's, or organization's carbon footprint can be measured by undertaking a GHG emissions assessment or other calculative activities denoted as carbon accounting. Once the size of a carbon footprint is known, a strategy can be devised to reduce it, e.g. by technological developments, better process and product management, changed Green Public or Private Procurement (GPP), carbon capture, consumption strategies, carbon offsetting and others.

For calculating personal carbon footprints, several free online carbon footprint calculators exist,[7] including a few supported by publicly available peer-reviewed data and calculations including the University of California, Berkeley's CoolClimate Network research consortium and CarbonStory.[8][9][10] These websites ask you to answer more or less detailed questions about your diet, transportation choices, home size, shopping and recreational activities, usage of electricity, heating, and heavy appliances such as dryers and refrigerators, and so on. The website then estimates your carbon footprint based on your answers to these questions. A systematic literature review was conducted to objectively determine the best way to calculate individual/household carbon footprints. This review identified 13 calculation principles and subsequently used the same principles to evaluate the 15 most popular online carbon footprint calculators. A recent study’s results by Carnegie Mellon's Christopher Weber found that the calculation of carbon footprints for products is often filled with large uncertainties. The variables of owning electronic goods such as the production, shipment, and previous technology used to make that product, can make it difficult to create an accurate carbon footprint. It is important to question, and address the accuracy of Carbon Footprint techniques, especially due to its overwhelming popularity.[11]

Calculating the carbon footprint of a product or service is a complex task, as stated earlier. One tool industry uses is Life-cycle assessment, where carbon footprint may be one of many factors taken into consideration when assessing a product or service.

The main influences on carbon footprints include population, economic output, and energy and carbon intensity of the economy.[12] These factors are the main targets of individuals and businesses in order to decrease carbon footprints. Production creates a large carbon footprint, scholars suggest that decreasing the amount of energy needed for production would be one of the most effective ways to decrease a carbon footprint. This is due to the fact that Electricity is responsible for roughly 37% of Carbon Dioxide emissions.[13] Coal production has been refined to greatly reduce carbon emissions; since the 1980s, the amount of energy used to produce a ton of steel has decreased by 50%.[14]

Average carbon footprint per person by country

The global average carbon footprint in 2007 was around 5.7 tons CO2e/cap. The EU average for this time was about 13.8 tons CO2e/cap, whereas for the U.S., Luxembourg and Australia it was over 25 tons CO2e/cap. The footprints per capita of countries in Africa and India were well below average. To set this numbers into context, assuming a global population around 9–10 billion by 2050 a carbon footprint of about 2–2.5 tons CO2e per capita is needed to stay within a 2 °C target. The carbon footprint calculations are based on a consumption based approach using a Multi-Regional Input-Output database, which accounts for all greenhouse gas (GHG) emissions in the global supply chain and allocates them to the final consumer of the purchased commodities. GHG emissions related to land use cover change are not included.[15]

Mobility (driving, flying & small amount from public transit), shelter (electricity, heating, construction) and food are the most important consumption categories determining the carbon footprint of a person. In the EU, the carbon footprint of mobility is evenly split between direct emissions (e.g. from driving private cars) and emissions embodied in purchased products related to mobility (air transport service, emissions occurring during the production of cars and during the extraction of fuel).[16]

The carbon footprint of U.S. households is about 5 times greater than the global average. For most U.S. households the single most important action to reduce their carbon footprint is driving less or switching to a more efficient vehicle.[17]

Direct carbon emissions

The carbon footprint of energy

The following table compares, from peer-reviewed studies of full life cycle emissions and from various other studies, the carbon footprint of various forms of energy generation: nuclear, hydro, coal, gas, solar cell, peat and wind generation technology.

Greenhouse emissions by electricity source
The Vattenfall study found renewable and nuclear generation responsible for far less CO2 than fossil fuel generation.
Emission factors of common fuels
Fuel/
resource
Thermal
(g[CO2-eq]/MJth)
Energy intensity
(Jth/Je)
Electric
(g[CO2-eq]/kW·he)
Coal B 91.50–91.72 2.62–2.85[18] 863–941[18]
Br 94.33 3.46[18] 1,175[18]
88 3.01 955[19]
Oil 73[20] 3.40 893[19]
Natural gas cc 68.20 577[18]
oc 68.4 751[18]
599[19]
Geothermal
power
TL 3~ 0–1[19]
TW 91–122[19]
Uranium
Nuclear power
WL N/A 0.18[18] 60[18]
WL 0.20[18] 65[18]
Hydroelectricity (run of river) N/A 0.046[18] 15[18]
Conc. solar power 40±15
Photovoltaics 0.33[18] 106[18]
Wind power 0.066[18] 21[18]

Note: 3.6 megajoules (MJ) = 1 kilowatt-hour (kW·h), thus 1 g/MJ = 3.6 g/kW·h.

Legend

B
Black coal (supercritical)–(new subcritical)
Br
Brown coal (new subcritical)
cc
combined cycle
oc
open cycle
TL
Low-temperature/closed-circuit (geothermal doublet)
TH
High-temperature/open-circuit
WL
Light water reactors
WH
Heavy water reactors, estimate.

These three studies thus concluded that hydroelectric, wind, and nuclear power produced the least CO2 per kilowatt-hour of any other electricity sources. These figures do not allow for emissions due to accidents or terrorism. Wind power and solar power, emit no carbon from the operation, but do leave a footprint during construction phase and maintenance during operation. Hydropower from reservoirs also has large footprints from initial removal of vegetation and ongoing methane (stream detritus decays anaerobically to methane in bottom of reservoir, rather than aerobically to CO2 if it had stayed in an unrestricted stream).[21]

The table above gives the carbon footprint per kilowatt-hour of electricity generated, which is about half the world's man-made CO2 output. The CO2 footprint for heat is equally significant and research shows that using waste heat from power generation in combined heat and power district heating, chp/dh has the lowest carbon footprint,[22] much lower than micro-power or heat pumps.

Passenger transport

Average carbon dioxide emissions (grams) per passenger mile (USA 2008)
Average carbon dioxide emissions (grams) per passenger mile (USA). Based on 'Updated Comparison of Energy Use & CO 2 Emissions From Different Transportation Modes, October 2008' (Manchester, NH: M.J. Bradley & Associates, 2008), p. 4, table 1.1[23]

This section gives representative figures for the carbon footprint of the fuel burned by different transport types (not including the carbon footprints of the vehicles or related infrastructure themselves). The precise figures vary according to a wide range of factors.

Flight

Some representative figures for CO2 emissions are provided by LIPASTO's survey of average direct emissions (not accounting for high-altitude radiative effects) of airliners expressed as CO2 and CO2 equivalent per passenger kilometre:[24]

  • Domestic, short distance, less than 463 km (288 mi): 257 g/km CO2 or 259 g/km (14.7 oz/mile) CO2e
  • Long distance flights: 113 g/km CO2 or 114 g/km (6.5 oz/mile) CO2e

However, emissions per unit distance traveled is not necessarily the best indicator for the carbon footprint of air travel, because the distances covered are commonly longer than by other modes of travel. It is the total emissions for a trip that matters for a carbon footprint, not the merely rate of emissions. For example, a greatly more distant holiday destination may be chosen than if another mode of travel were used, because air travel makes the longer distance feasible in the limited time available.[25]

Road

CO2 emissions per passenger-kilometre (pkm) for all road travel for 2011 in Europe as provided by the European Environment Agency:[26]

  • 109 g/km CO2 (Figure 2)

For vehicles, average figures for CO2 emissions per kilometer for road travel for 2013 in Europe, normalized to the NEDC test cycle, are provided by the International Council on Clean Transportation:[27]

Average figures for the United States are provided by the US Environmental Protection Agency,[28] based on the EPA Federal Test Procedure, for the following categories:

  • Passenger cars: 200 g CO2/km (322 g/mi)
  • Trucks: 280 g CO2/km (450 g/mi)
  • Combined: 229 g CO2/km (369 g/mi)

Rail

In 2005, the US company Amtrak's carbon dioxide equivalent emissions per passenger kilometre were 0.116 kg,[29][30] about twice as high as the UK rail average (where much more of the system is electrified),[31] and about eight times a Finnish electric intercity train.[32]

Sea

Average carbon dioxide emissions by ferries per passenger-kilometre seem to be 0.12 kg (4.2 oz).[33] However, 18-knot ferries between Finland and Sweden produce 0.221 kg (7.8 oz) of CO2, with total emissions equalling a CO2 equivalent of 0.223 kg (7.9 oz), while 24–27-knot ferries between Finland and Estonia produce 0.396 kg (14.0 oz) of CO2 with total emissions equalling a CO2 equivalent of 0.4 kg (14 oz).[34]

Indirect carbon emissions: the carbon footprints of products

Several organizations offer footprint calculators for public and corporate use, and several organizations have calculated carbon footprints of products.[35] The US Environmental Protection Agency has addressed paper, plastic (candy wrappers), glass, cans, computers, carpet and tires. Australia has addressed lumber and other building materials. Academics in Australia, Korea and the US have addressed paved roads. Companies, nonprofits and academics have addressed mailing letters and packages. Carnegie Mellon University has estimated the CO2 footprints of 46 large sectors of the economy in each of eight countries. Carnegie Mellon, Sweden and the Carbon Trust have addressed foods at home and in restaurants.

The Carbon Trust has worked with UK manufacturers on foods, shirts and detergents, introducing a CO2 label in March 2007. The label is intended to comply with a new British Publicly Available Specification (i.e. not a standard), PAS 2050,[36] and is being actively piloted by The Carbon Trust and various industrial partners.[37] As of August 2012 The Carbon Trust state they have measured 27,000 certifiable product carbon footprints.[38]

Evaluating the package of some products is key to figuring out the carbon footprint.[39] The key way to determine a carbon footprint is to look at the materials used to make the item. For example, a juice carton is made of an aseptic carton, a beer can is made of aluminum, and some water bottles either made of glass or plastic. The larger the size, the larger the footprint will be.

Food

In a 2014 study by Scarborough et al., the real-life diets of British people were surveyed and their dietary greenhouse gas footprints estimated.[40] Average dietary greenhouse-gas emissions per day (in kilograms of carbon dioxide equivalent) were:

  • 7.19 for high meat-eaters
  • 5.63 for medium meat-eaters
  • 4.67 for low meat-eaters
  • 3.91 for fish-eaters
  • 3.81 for vegetarians
  • 2.89 for vegans

Textiles

The precise carbon footprint of different textiles varies considerably according to a wide range of factors. However, studies of textile production in Europe suggest the following carbon dioxide equivalent emissions footprints per kilo of textile at the point of purchase by a consumer:[41]

  • Cotton: 8
  • Nylon: 5.43
  • PET (e.g. synthetic fleece): 5.55
  • Wool: 5.48

Accounting for durability and energy required to wash and dry textile products, synthetic fabrics generally have a substantially lower carbon footprint than natural ones.[42]

Materials

The carbon footprint of materials (also known as embodied carbon) varies widely. The carbon footprint of many common materials can be found in the Inventory of Carbon & Energy database,[43] the GREET databases and models,[44] and LCA databases via openLCA Nexus[45]

Cement

Cement production and carbon footprint resulting from soil sealing was 8.0 Mg person−1 of total per capita CO2 emissions (Italy, year 2003); the balance between C loss due to soil sealing and C stocked in man-made infrastructures resulted in a net loss to the atmosphere, -0.6 Mg C ha−1 y−1.[46]

Schemes to reduce carbon emissions: Kyoto Protocol, carbon offsetting, and certificates

Carbon dioxide emissions into the atmosphere, and the emissions of other GHGs, are often associated with the burning of fossil fuels, like natural gas, crude oil and coal. While this is harmful to the environment, carbon offsets can be purchased in an attempt to make up for these harmful effects.

The Kyoto Protocol defines legally binding targets and timetables for cutting the GHG emissions of industrialized countries that ratified the Kyoto Protocol. Accordingly, from an economic or market perspective, one has to distinguish between a mandatory market and a voluntary market. Typical for both markets is the trade with emission certificates:

Mandatory market mechanisms

To reach the goals defined in the Kyoto Protocol, with the least economical costs, the following flexible mechanisms were introduced for the mandatory market:

The CDM and JI mechanisms requirements for projects which create a supply of emission reduction instruments, while Emissions Trading allows those instruments to be sold on international markets.

- Projects which are compliant with the requirements of the CDM mechanism generate Certified Emissions Reductions (CERs).
- Projects which are compliant with the requirements of the JI mechanism generate Emission Reduction Units (ERUs).

The CERs and ERUs can then be sold through Emissions Trading. The demand for the CERs and ERUs being traded is driven by:

- Shortfalls in national emission reduction obligations under the Kyoto Protocol.
- Shortfalls amongst entities obligated under local emissions reduction schemes.

Nations which have failed to deliver their Kyoto emissions reductions obligations can enter Emissions Trading to purchase CERs and ERUs to cover their treaty shortfalls. Nations and groups of nations can also create local emission reduction schemes which place mandatory carbon dioxide emission targets on entities within their national boundaries. If the rules of a scheme allow, the obligated entities may be able to cover all or some of any reduction shortfalls by purchasing CERs and ERUs through Emissions Trading. While local emissions reduction schemes have no status under the Kyoto Protocol itself, they play a prominent role in creating the demand for CERs and ERUs, stimulating Emissions Trading and setting a market price for emissions.

A well-known mandatory local emissions trading scheme is the EU Emissions Trading Scheme (EU ETS).

New changes are being made to the trading schemes. The EU Emissions Trading Scheme is set to make some new changes within the next year. The new changes will target the emissions produced by flight travel in and out of the European Union.[47]

Other nations are scheduled to start participating in Emissions Trading Schemes within the next few year. These nations include China, India and the United States.[47]

Voluntary market mechanisms

In contrast to the strict rules set out for the mandatory market, the voluntary market provides companies with different options to acquire emissions reductions. A solution, comparable with those developed for the mandatory market, has been developed for the voluntary market, the Verified Emission Reductions (VER). This measure has the great advantage that the projects/activities are managed according to the quality standards set out for CDM/JI projects but the certificates provided are not registered by the governments of the host countries or the Executive Board of the UNO. As such, high quality VERs can be acquired at lower costs for the same project quality. However, at present VERs can not be used in the mandatory market.

The voluntary market in North America is divided between members of the Chicago Climate Exchange and the Over The Counter (OTC) market. The Chicago Climate Exchange is a voluntary yet legally binding cap-and-trade emission scheme whereby members commit to the capped emission reductions and must purchase allowances from other members or offset excess emissions. The OTC market does not involve a legally binding scheme and a wide array of buyers from the public and private spheres, as well as special events that want to go carbon neutral. Being carbon neutral refers to achieving net zero carbon emissions by balancing a measured amount of carbon released with an equivalent amount sequestered or offset, or buying enough carbon credits to make up the difference.

There are project developers, wholesalers, brokers, and retailers, as well as carbon funds, in the voluntary market. Some businesses and nonprofits in the voluntary market encompass more than just one of the activities listed above. A report by Ecosystem Marketplace shows that carbon offset prices increase as it moves along the supply chain—from project developer to retailer.[48]

While some mandatory emission reduction schemes exclude forest projects, these projects flourish in the voluntary markets. A major criticism concerns the imprecise nature of GHG sequestration quantification methodologies for forestry projects. However, others note the community co-benefits that forestry projects foster. Project types in the voluntary market range from avoided deforestation, afforestation/reforestation, industrial gas sequestration, increased energy efficiency, fuel switching, methane capture from coal plants and livestock, and even renewable energy. Renewable Energy Certificates (RECs) sold on the voluntary market are quite controversial due to additionality concerns.[49] Industrial Gas projects receive criticism because such projects only apply to large industrial plants that already have high fixed costs. Siphoning off industrial gas for sequestration is considered picking the low hanging fruit; which is why credits generated from industrial gas projects are the cheapest in the voluntary market.

The size and activity of the voluntary carbon market is difficult to measure. The most comprehensive report on the voluntary carbon markets to date was released by Ecosystem Marketplace and New Carbon Finance in July 2007.[48]

ÆON of Japan is firstly approved by Japanese authority to indicate carbon footprint on three private brand goods in October 2009.

Ways to reduce personal carbon footprint

The most common way to reduce the carbon footprint of humans is to Reduce, Reuse, Recycle, Refuse.

This can also be done by using reusable items such as thermoses for daily coffee or plastic containers for water and other cold beverages rather than disposable ones. If that option isn't available, it is best to properly recycle the disposable items after use. When one household recycles at least half of their household waste, they can save 1.2 tons of carbon dioxide annually[50].

Another easy option is to drive less. By walking or biking to the destination rather than driving, not only is a person going to save money on gas, but they will be burning less fuel and releasing fewer emissions into the atmosphere. However, if walking is not an option, one can look into carpooling or mass transportation options in their area.

Yet another option for reducing the carbon footprint of humans is to use less air conditioning and heating in the home. By adding insulation to the walls and attic of one's home, and installing weather stripping or caulking around doors and windows one can lower their heating costs more than 25 percent. Similarly, one can very inexpensively upgrade the "insulation" (clothing) worn by residents of the home.[51] For example, it's estimated that wearing a base layer of long underwear (top and bottom) made from a lightweight, super insulating fabric like microfleece (aka Polartec®, Capilene®) can conserve as much body heat as a full set of clothing, allowing a person to remain warm with the thermostat lowered by over 5 °C.[51][52] These measures all help because they reduce the amount of energy needed to heat and cool the house. One can also turn down the heat while sleeping at night or away during the day, and keep temperatures moderate at all times. Setting the thermostat just 2 degrees lower in winter and higher in summer could save about 1 ton of carbon dioxide each year.[50]

Choice of diet is a major influence on a person's carbon footprint. Animal sources of protein (especially red meat), rice (typically produced in high methane-emitting paddies), foods transported long distance and/or via fuel-inefficient transport (e.g., highly perishable produce flown long distance) and heavily processed and packaged foods are among the major contributors to a high carbon diet. Scientists at the University of Chicago have estimated[53] "that the average American diet – which derives 28% of its calories from animal foods – is responsible for approximately one and a half more tonnes of greenhouse gasses – as CO2 equivalents – per person, per year than a fully plant-based, or vegan, diet."[54] Their calculations suggest that even replacing one third of the animal protein in the average American's diet with plant protein (e.g., beans, grains) can reduce the diet's carbon footprint by half a tonne. Exchanging two thirds of the animal protein with plant protein is roughly equivalent to switching from a Toyota Camry to a Prius. Finally, throwing food out not only adds its associated carbon emissions to a person or household's footprint, it adds the emissions of transporting the wasted food to the garbage dump and the emissions of food decomposition, mostly in the form of the highly potent greenhouse gas, methane.

The carbon handprint movement emphasizes individual forms of carbon offsetting, like using more public transportation or planting trees in deforested regions, to reduce one's carbon footprint and increase their "handprint."[55]

A July 2017 study published in Environmental Research Letters argued that the most significant way individuals could mitigate their own carbon footprint is to have fewer children, followed by living without a vehicle, forgoing air travel and adopting a plant-based diet.[56]

Ways to reduce industry's carbon footprint

In manufacturing this can be done by recycling the packing materials, by selling the obsolete inventory of one industry to the industry who is looking to buy unused items at lesser price to become competitive. Nothing should be disposed off into the soil, all the ferrous materials which are prone to degrade or oxidize with time should be sold as early as possible at reduced price.

Carbon Footprints can be reduced through the development of alternative projects, such as solar and wind energy, which are environment friendly, renewable resources, or reforestation, the restocking of existing forests or woodlands that have previously been depleted. These examples are known as Carbon Offsetting, the counteracting of carbon dioxide emissions with an equivalent reduction of carbon dioxide in the atmosphere.[57]

Furthermore, the carbon footprint in industry can be reduced by optimizing the supply chain. A life cycle or supply chain carbon footprint study can provide useful data which will help the business to identify critical areas for improvement and provides a focus. Such studies also demonstrate a company’s commitment to reducing carbon footprint now ahead of other competitors as well as preparing companies for potential regulation. In addition to increased market advantage and differentiation eco-efficiency can also help to reduce costs where alternative energy systems are implemented.

Lean Six Sigma is a method used in manufacturing to reduce wastes throughout the production of a product, by reducing energy or physical wastes the carbon footprint of a product will be reduced.

See also

References

Citations

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Sources

External links

Carbon Management at Curlie

Cambridge SCA

Cambridge SCA (Cambridge Student Community Action) is a registered charity which encourages and provides community volunteering opportunities for the students of the University of Cambridge. Projects typically provide services to disadvantaged groups within the local community and provide students with valuable learning opportunities and a chance to make a difference. Cambridge SCA runs 10 of its own 'Internal Projects', each of which are headed by student Project Leaders - these projects include 'Big Siblings', 'Parklife', 'Betty Stubbens Musical Entertainment Group' and 'Teaching English as a Second Language'. They also offer volunteering opportunities with over 60 external organisations, such as Cambridge Carbon Footprint, Headway and the Cambridge Rape Crisis Centre.

Carbon Trust

The Carbon Trust is a for-mission company that helps governments, organisations and companies reduce their carbon emissions and become more resource efficient. Its stated mission is to accelerate the move to a sustainable, low carbon economy.

The Carbon Trust helps reduce carbon emissions and increase resource efficiency through providing specialist help, support and advice. It has operations and projects across the globe, supporting companies and organisations wherever help is needed. Office bases include London, Beijing, Pretoria, Mexico City, Edinburgh, Washington DC and Cardiff.

Carbon accounting

Carbon accounting refers generally to processes undertaken to "measure" amounts of carbon dioxide equivalents emitted by an entity. It is used by nation states, corporations, individuals – to create the carbon credit commodity traded on carbon markets (or to establish the demand for carbon credits). Correspondingly, examples for products based upon forms of carbon accounting can be found in national inventories, corporate environmental reports or carbon footprint calculators. Likening sustainability measurement, as an instance of ecological modernisation discourses and policy, carbon accounting is hoped to provide a factual ground for carbon-related decision-making. However, social scientific studies of accounting challenge this hope, pointing to the socially constructed character of carbon conversion factors or of the accountants' work practice which cannot implement abstract accounting schemes into reality.While natural sciences claim to know and measure carbon, for organisations it is usually easier to employ forms of carbon accounting to represent carbon. The trustworthiness of accounts of carbon emissions can easily be contested. Thus, how well carbon accounting represents carbon is difficult to exactly know. Science and Technology Studies scholar Donna Haraway's pluralised concept of knowledge, i.e. knowledges, can well be used to understand better the status of knowledge produced by carbon accounting: carbon accounting produced a version of understanding of carbon emissions. Other carbon accountants would produce other results.

Carbon diet

A carbon diet refers to reducing the impact on climate change by reducing greenhouse gas production specifically, CO2 production. In today’s society, humans produce CO2 in every day activities such as driving, heating, deforestation and the burning of fossil fuels such as coal, oil and gas. It has been found that carbon dioxide from the burning of coal, natural gas, and oil for electricity and heat is the largest single source of global greenhouse gas emissions. For years, governments and corporations have been attempting to balance out their emissions by participating in carbon-offsetting — the practice in which they invest in renewable energy to compensate for the global-warming pollution that they produce. Despite these efforts the results are still far off and we continue to see growth in CO2 concentration. Now, a growing number of individuals are trying to make a reduction in the amount of CO2 that is being produced by participating in low carbon dieting. This small adjustment in household CO2 production has the potential to reduce emissions much more quickly than other kinds of changes and it deserves explicit consideration as part of climate policy. It can potentially help avoid “overshoot” of greenhouse gas concentration targets; provide a demonstration effect; reduce emissions at low cost; and buy time to develop new technologies, policies, and institutions to reach long-term greenhouse gas emission targets and to develop adaptation strategies.

Carbon neutrality

Carbon neutrality, or having a net zero carbon footprint, refers to achieving net zero carbon dioxide emissions by balancing carbon emissions with carbon removal (often through carbon offsetting) or simply eliminating carbon emissions altogether (the transition to a "post-carbon economy"). It is used in the context of carbon dioxide-releasing processes associated with transportation, energy production, and industrial processes.

The best practice for organizations and individuals seeking carbon neutral status entails reducing and/or avoiding carbon emissions first so that only unavoidable emissions are offset or otherwise balanced out. Carbon neutral status can be achieved in two ways:

Balancing carbon dioxide emissions with carbon removal beyond natural processes, often through carbon offsetting, or the process of removing or sequestering carbon dioxide from the atmosphere to make up for emissions elsewhere. Some carbon-neutral fuels work in much the same way by being made from carbon dioxide, either already offset or simply as part of natural processes, despite producing carbon emissions themselves. Much more extreme forms of carbon dioxide removal may also be used.

Simply eliminating carbon emissions altogether (the concept of the "post-carbon economy") through the use of renewable energy that does not produce carbon emissions at all (such as wind and solar power). Carbon projects and emissions trading are often used to reduce carbon emissions, and carbon dioxide can sometimes even be prevented from entering the atmosphere entirely (such as by carbon scrubbing).The concept may be extended to include other greenhouse gases measured in terms of their carbon dioxide equivalence. The phrase was the New Oxford American Dictionary's Word of the Year for 2006. The term "climate neutral" reflects the broader inclusiveness of other greenhouse gases in climate change, even if CO2 is the most abundant. The terms are used interchangeably throughout this article.

Denise Sheehan

Denise Sheehan is an experienced manager with more than 25 years of experience in government and the non-profit sectors. She currently serves as Executive Vice President at Capitol Hill Management Services (CHMS), a management consulting firm specializing in non-profit management. As part of her role at CHMS, Denise serves as Sr. Advisor for the New York Battery and Energy Storage Technology Consortium (NY-BEST), where she works to advance the battery and energy storage industry for electric grid and transportation applications.

Denise's previous experience includes 10 years at the New York State Department of Environmental Conservation, where she held a variety of senior management positions from 1998-2005 and served as Commissioner from 2005-2007. Denise led the Department's efforts to address climate change, protect open space, revitalize brownfields, reduce harmful air emissions, improve water quality and protect fish and wildlife resources.

Denise also previously worked for The Climate Registry, a North American non-profit organization, based in Los Angeles, CA, which helps businesses and organizations reduce their carbon footprint and manage their risk.She has previously served as Director of Planning and Economic Development for Colonie, New York. Denise's professional experience also includes more than 10 years at the NYS Division of the Budget where she worked on the state's environmental and energy-related budgets.

Denise has served on a number of non-profit boards. She currently serves as the Chair of the American Red Cross - Northeastern NY Chapter.

Dopplr

Dopplr was a free social networking service, launched in 2007, that allowed users to create itineraries of their travel plans and spot correlations with their contacts' travel plans in order to arrange meetings at any point on their journey. Additional features included allowing the user to calculate the carbon footprint their journeys have produced. The site was named after Christian Doppler, discoverer of the Doppler effect. The company was based in the "Silicon Roundabout" area of London.

Energy Biosciences Institute

The Energy Biosciences Institute (EBI) is an organization dedicated to developing new sources of energy and reducing the impact of energy consumption. It was created in 2007 to apply advanced knowledge of biology to the challenges of responsible, sustainable energy production and use.

Its main goal is to develop next-generation biofuels—that is, biofuels that are made from the non-edible parts of plants and reduce greenhouse gas emissions.Funded by BP, which initially agreed to contribute $500 million over a 10-year-period, with $350 million slated for academic research, EBI is a joint initiative between the University of California, Berkeley (UCB), Lawrence Berkeley National Laboratory, the University of Illinois at Urbana-Champaign, and the energy company. It is the largest public-private venture of its kind. All research from its academic labs is published and publicly available. More information about the EBI is available to the public through the EBI Bulletin and its magazine, Bioenergy Connection, which cover emerging trends in the field of bioenergy.)EBI was designed as a creative, multidisciplinary institution. Because bioenergy research is so complex, the institute promotes a holistic view by encouraging scientists from many disciplines – biology, chemistry, botany, environmental science, economics, and others – to collaborate on investigations.

The institute’s main research areas are:

feedstock development (work on plant sources of biofuel)

biomass depolymerization (breaking down the plant cell wall to enable sugar, or energy, extraction)

biofuel production

the environmental, social, and economic impact of bioenergy development

fossil fuel bioprocessing (using microbial processes to help make oil recovery “greener” and to shrink its carbon footprint)

Leather

Leather is a natural durable and flexible material created by tanning animal rawhides and skins. The most common raw material is cattle hide. It can be produced at manufacturing scales ranging from artisan to modern industrial scale.

Leather is used to make a variety of articles, including footwear, automobile seats, clothing, bags, book bindings, fashion accessories, and furniture. It is produced in a wide variety of types and styles and decorated by a wide range of techniques. The earliest record of leather artifacts dates back to 2200 BC.

Lighthouse Tower

The Lighthouse Tower is a supertall, commercial skyscraper to be built in Dubai, United Arab Emirates designed by multi-national architectural firm Atkins. It will be constructed in the DIFC, is set rise to 402 m (1,319 feet) and have 66 floors. The tower is a Green Building with a huge emphasis put on reducing its carbon footprint and conserving energy.

The tower rises as two separate towers, bridged from level 10, all the way up to approximately 300 meters above ground. The structure is to hold a number of skygardens. Construction was suspended in 2009.

List of countries by greenhouse gas emissions per capita

This is a list of countries by total greenhouse gas (GHG) emissions per capita by year. It is based on data for carbon dioxide, methane, nitrous oxide, perfluorocarbon, hydrofluorocarbon, and sulfur hexafluoride emissions compiled by the World Resources Institute, divided by the population estimate by the United Nations (for July 1) of the same year. The emissions data do not include land-use change and forestry.

Melon Bicycles

Melon Bicycles was a folding bicycle manufacturer based in Chapel Hill, North Carolina. Many cyclists refer to the company as Melon Bikes, Melon Bicycles, or simply Melon. Melon Bicycles went out of business in 2014.Melon worked in collaboration with Chick-fil-A and other companies in programs to improve overall employee well-being and carbon footprint. These programs encourage employees to ride their bikes to work, thus increasing exercise and cutting down on fuel emissions.

Substitute natural gas

Substitute natural gas (SNG), or synthetic natural gas, is a fuel gas that can be produced from fossil fuels such as lignite coal, oil shale, or from biofuels (when it is named bio-SNG) or from renewable electrical energy.

The Great Plains Synfuels Plant injects approximately 4.1 million m3/day of SNG from lignite coal into the United States national gas grid. The production process of SNG at the Great Plains plant involves gasification, gas cleaning, shift, and methanation. China is constructing nearly 30 nos massive SNG production plants from coal / lignite with aggregate annual capacity of 120 billion standard cubic meters of SNG. SNG in the form of LNG or CNG can be used in road, rail, air and marine transport vehicles as a substitute for costly diesel, petrol, etc. The carbon footprint of SNG derived from coal is comparable to petroleum products. Bio-SNG has a much smaller carbon footprint when compared to petroleum products. LPG can also be produced by synthesising SNG with partial reverse hydrogenation at high pressure and low temperature. LPG is more easily transportable than SNG, more suitable as fuel in two wheeler or smaller HP vehicles /engines and also fetches higher price in international market due to short supply.

Renewable electrical energy can also be used to create SNG (methane) via for example electrolysis of water or via a PEM fuel cell in reverse to create hydrogen which is then reacted with CO2 from for example CSS/U Utilisation in the Sabatier reaction.

CO2 + 4H2 → CH4 + 2H2O

Sustainable advertising

Sustainable advertising addresses the carbon footprint and other negative environmental and social impacts associated with the production and distribution of advertising materials. A growing number of companies are making a commitment to the reduction of their environmental impact associated with advertising production and distribution.

Therm

The therm (symbol, thm) is a non-SI unit of heat energy equal to 100000 British thermal units (Btu). It is approximately the energy equivalent of burning 100 cubic feet (2.83 cubic metres) – often referred to as 1 CCF – of natural gas.

Since natural gas meters measure volume and not energy content, a therm factor is used by natural gas companies to convert the volume of gas used to its heat equivalent, and thus calculate the actual energy use. The therm factor is usually expressed in units of therms per CCF. It will vary with the mix of hydrocarbons in the natural gas. Natural gas with a higher than average concentration of ethane, propane or butane will have a higher therm factor. Impurities, such as carbon dioxide or nitrogen, lower the therm factor.

The volume of the gas is calculated as if measured at standard temperature and pressure (STP).

One therm is equal to about 105.5 megajoules, 25200 kilocalories, or 29.3 kilowatt-hours. One therm can also be provided by about 96.7 cubic feet (2.74 m3) of natural gas. The therm sometimes has been confused with the thermie. The names of both units come from the Greek word for heat.

Time pressure gauge

A time pressure gauge is an instrument that digitally displays pressure data divided into appropriate time intervals. While a pressure gauge indicates a general unit amount, only a time pressure gauge accounts for varying consumption and capacity in relation to time remaining.

Wildpoldsried

Wildpoldsried is a municipality in the district of Oberallgäu in Bavaria in Germany. The village has been recognized for its exceptional achievements in renewable energy production and in reducing its carbon footprint.

Zero carbon housing

Zero Carbon Housing and Zero Energy Housing are terms used interchangeably to define single family dwellings with a very high energy efficiency rating. Zero Energy Housing requires a very low amount of energy to provide the daily needs and functions for the family occupying the home.The term carbon footprint, at present, does not have a concrete and universal definition. Thomas Wiedmann proposed a well received and generally accepted definition that defines carbon footprint as a measure of the total amount of carbon dioxide emissions directly and indirectly caused by an activity or accumulated over the life stages of a product. A carbon footprint can be divided into 4 levels: personal, product, organizational, and country. A personal carbon footprint is a measure of greenhouse gas emissions that are a result of daily life. Examples of contributors to personal carbon footprint are clothing, food, housing, and traffic. The emissions from the entire life of a product, extraction of raw materials and manufacturing, and recycling or disposal contribute to product carbon footprint. Greenhouse gas emissions from energy used in buildings, industrial processes, and company vehicles account for organizational carbon footprints. An entire country collectively generates a carbon footprint from carbon dioxide emissions generated by the consumption of materials and energy, vegetations and other carbon sequestrations, as well as the indirect and direct emissions caused by import and export activities. Zero carbon housing is a result of the building sector being one of the largest contributors to greenhouse gas emissions in urban areas.The calculation of the carbon footprint becomes detailed when considering secondary factors. Secondary factors involve the home’s occupant lifestyle such as diet, foods are consumed (example organic vs. non organic), frequency of yearly air travel, commuting mileage to and from work, school, etc., use of public transportation, and number, type, and use of private vehicles. Secondary factors also include fashion or type of clothes purchased and worn, frequency of recycling, recreational activities and use of financial and other services throughout a given year. The frequency of airline flights in a year is considered due to the amount of fuel consumption and other energy usage and emissions generated by one flight. A person that travels frequently may have a significantly bigger carbon footprint than someone who flies once a year for a vacation. The emissions for an individual flight are calculated by using the greater circle method. First, the distance between airports is determined. Then calculations are completed to account for indirect distances and by an emissions factor in relation to the type of flight (international or a short flight, and what class seating the person is in). Another contributing factor to a person’s carbon footprint is their personal vehicle which includes the type of car driven, the efficiency or miles per gallon (MPG) rating, and the number of miles driven each year. The frequency of public transportation used by an individual, miles traveled on public transportation and the type of public transportation used such as bus, train, or subway contributes to their carbon footprint as well. Other factors, as trivial as they might seem, are included in the calculation of a person’s carbon foot print to include things such as the type of diet. A vegetarian compared to a person that eats a lot of red meat will have a lower carbon footprint. All factors being the same except diet, a vegetarian secondary carbon footprint averages three metric tonnes of CO2, one tonne less than the individual who consumes meat. Other factors include the purchase of local and /or organically grown produce vs. imported items, the latest clothes fashions vs. more conventional purchases, buying individually packaged products vs. buying in bulk, recycling activities, and the types of recreation such as carbon-free activities like hiking and cycling or carbon-intensive activities like skydiving or boating.

Zoombu

Zoombu was an online door-to-door journey search engine for Europe, now defunct after takeover by Skyscanner. Users could enter their starting and destination addresses and the service searches thousands of routes across combinations of transportation including flights, trains, ferries, and ground transfers including taxis, driving and car parking. Results could be filtered according to specific user preferences, budget, time available and even carbon footprint. The service was independent from any particular carrier and searches hundreds of transportation carriers. Zoombu did not include booking capabilities, but instead it linked to transportation suppliers where it is possible to book components of any route.

The company was based in South-West London.

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