Carbon Footprint

Carbon Footprint – Reduction is essential to improve Global Environment:

Environment protection, Global warming and climate change are most priority to everybody – nations’, companies’ and individuals’. ‘Carbon footprint’ has become a widely used term and concept in the public debate on responsibility and abatement action against the threat of global climate change. It had a tremendous increase in public appearance over the last few months and years and is now a buzzword widely used across the media, the government and in the business world. Thus, reduction of carbon footprints is today’s topmost concern, especially when we perceive global environment in the context of post-Kyoto scenario.

Meaning of carbon footprint –

People may ask, what exactly is a ‘carbon footprint’? Despite its ubiquitous appearance there seems to be no clear definition of this term and there is still some confusion what it actually means and measures and what unit is to be used. The spectrum of definitions ranges from direct CO2 emissions to full life-cycle greenhouse gas emissions and not even the units of measurement are clear.

Now we have definition of ‘carbon footprint’. A carbon footprint is a ‘measure of the impact of human activities leave on the environment, directly and indirectly or is accumulated over the life stages of a product,  in terms of the amount of green house gases produced, measured in units of carbon dioxide’. In other words, a carbon footprint is the total amount of CO2 and other greenhouse gases, emitted over the full life cycle of a product or service. It is expressed as grams of CO2 equivalents, which accounts for the different global warming effects of different greenhouse gases. This established method has been standardized under ISO 14044. It is meant to be useful for individuals and organizations to conceptualize their personal or organizational impact in contributing to global warming. Environment protection and climate change are most priority of most of the countries, companies and individual. Reducing carbon foot prints is top concern of every individual, company and nation.

Many activities generate carbon emissions, which contribute to accelerating global warming and climate change. Total carbon footprint/emission quantification would include energy related emissions from human activities - that is, from heat, light, power and refrigeration and all transport related emissions from cars, freight and distribution, etc. By measuring the carbon footprint through such tools as carbon calculators, we can get a better sense of what the individual impact is and which parts of our lifestyle deserve the greatest attention.

Carbon is the essential ingredient of all fossil fuels - coal, oil or gas. When these fuels are burned to provide energy, carbon dioxide (CO2), a "greenhouse gas", is released to the Earth’s atmosphere. As we have become more dependent on carbon-based fuels, we have seen a rapid increase in the atmospheric concentration of CO2; from around 280 parts per million (ppm) before the industrial revolution, to more than 370 ppm today. If current trends of fossil fuel use continue without modification, the concentration of CO2 is likely to exceed 700 ppm by the end of this century. According to experts, this could lead to global warming of between 1.4 and 5.8°C, which may results in more frequent severe weather conditions and damage to many natural ecosystems.

Many believe that it is realistic to promote actions that ensure stabilization of atmospheric CO2 concentrations at around 500-550 ppm. This is a considerable challenge, given that global energy demand is expected to double between 2000 and 2050. To achieve carbon stabilization, we need to ask ourselves following tough questions:

a. What exactly is our current relationship with carbon?

b. How can we reduce our dependency on carbon emitting technologies and fuels - our ‘carbon footprint’?

c. What steps are others taking around the world?

Calculating carbon footprints –

Carbon footprints are calculated using a method called life cycle assessment (LCA). As carbon footprint is the measure of carbon dioxide during the life of a particular industry, ‘life cycle’ concept of carbon footprint is familiar. The life cycle concept of the carbon footprint means that it is all-encompassing and includes all possible causes that give rise to carbon emissions. All direct (on-site, internal) and indirect emissions (off-site, external, embodied, upstream, downstream etc.) need to be taken into account.

In other words, this method is used to analyze the cumulative environmental impacts of a process or product through all the stages of its life. It takes into account energy inputs and emission outputs throughout the whole production chain from exploration and extraction of raw materials to processing, transport and final use.

All reputable international guidelines and standards on carbon footprint calculation recommend the life cycle analysis approach. The LCA method is internationally accredited by ISO 14000 standards. Calculating a Life Cycle Assessment according to ISO 14040, allows all carbon emissions that are material to a business, an activity or a product to be captured in a systematic way. Life Cycle Assessment according to ISO 14044 is the state-of-the art methodology to determine carbon footprint of a product. Facilitating such a “cradle-to-grave” carbon footprint analysis of a product will disclose real carbon footprint,

Assessment of Power generation technologies on carbon footprint –

Emission of carbon dioxide and other greenhouse gases are mostly associated with energy conversion processes; especially with fossil fuel based power plants. The carbon content released during such energy conversion process reaches the atmosphere and is extensively responsible for the global warming process and climate change. In this context, the concept of carbon footprint and reduction of it has become very relevant as the Kyoto Protocol defines legally binding targets and timetables for cutting emission of the greenhouse gases by industrialized nations that ratified the Kyoto Protocol.

All electricity generation systems have a ‘carbon footprint’, that is, at some points during their construction and operation carbon dioxide (CO2) and other greenhouse gases are emitted to the atmosphere. To compare the impacts of various different technologies accurately, the total CO2 amounts emitted throughout a system’s life must be calculated. Emissions can be both, direct – arising during operation of the power plant, and indirect – arising during other non-operational phases of the life cycle. Fossil fuel technologies have the largest carbon footprints, because they burn these fuels during operation. Non-fossil fuel based technologies such as wind, photovoltaic (solar), hydro, biomass, wave / tidal and nuclear are often referred to as ‘low carbon’ or ‘carbon neutral’ because they do not emit CO2 during their operation. However, they are not ‘carbon free’ forms of generation, since CO2 emissions do arise in other phases of their life cycle such as during extraction, construction, maintenance and decommissioning.

A ‘carbon footprint’ is the total amount of CO2 and other greenhouse gases, emitted over the full life cycle of a process or product. It is expressed as grams of CO2 equivalent per kilowatt hour of generation (gCO2eq/kWh), which accounts for the different global warming effects of other greenhouse gases.

a. Carbon footprint of ‘Fossil fuelled technologies’ –

The carbon footprint of fossil fuelled power plants is dominated by emissions during their operation. Indirect emissions during other life cycle phases such as raw material extraction and plant construction are relatively minor.

i) Coal burning power systems have the largest carbon footprint of all the electricity generation systems analyzed here. Conventional coal combustion systems result in emissions of the order of >1,000 gCO2eq/kWh. Lower emissions can be achieved using newer gasification plants.

ii) Oil accounts for only a very small proportion (about 1%) of the electricity generated in most of the countries. It is primarily used as a back-up fuel to cover peak electricity demand periods. The average carbon footprint of oil-fired electricity generation plants is ~650gCO2eq/kWh.

iii) Current gas powered electricity generation has a carbon footprint around half that of coal (~500gCO2eq/kWh), because gas has a lower carbon content than coal. Like coal fired plants, gas plants could co-fire biomass to reduce carbon emissions in the future.

b. Carbon footprint of ‘Low carbon technologies’ –

In contrast to fossil fuelled power generation, the common feature of renewable and nuclear energy systems is that emissions of greenhouse gases and other atmospheric pollutants are ‘indirect’, that is, they arise from stages of the life cycle other than power generation.

i) Biomass - Biomass is obtained from organic matter, either directly from dedicated energy crops like short-rotation coppice willow and grasses such as straw, or indirectly from industrial and agricultural by-products such as wood-chips. The use of biomass is generally classed as ‘carbon neutral’ because the CO2 released by burning is equivalent to the CO2 absorbed by the plants during their growth. However, other life cycle energy inputs affect this ‘carbon neutral’ balance, for example emissions arise from fertilizer production, harvesting, drying and transportation.

Biomass fuels are much lower in energy and density than fossil fuels. This means that large quantities of biomass must be grown and harvested to produce enough feedstock for combustion in a power station. Transporting large amounts of feedstock increases life cycle CO2 emissions, so biomass electricity generation is most suited to small-scale local generation facilities,

ii) Photovoltaic (PV) - Photovoltaic (PV), also known as solar cells, are made of crystalline silicon, a semi-conducting material which converts sunlight into electricity. The silicon required for PV modules is extracted from quartz sand at high temperatures. This is the most energy intensive phase of PV module production, accounting for 60% of the total energy requirement. Life cycle CO2 emissions for photovoltaic power systems are currently 58gCO2eq/kWh. However, future reductions in the carbon footprint of PV cells are expected to be achieved in thin film technologies which use thinner layers of silicon, and with the development new semi-conducting materials which are less energy intensive.

iii) Marine technologies (wave and tidal) - There are two types of marine energy devices; wave energy converters and tidal (stream and barrage) devices. Marine based electricity generation is still an emerging technology and is not yet operating on a commercial scale.

iv) Hydro - Hydropower converts the energy from flowing water, via turbines and generators, into electricity. There are two main types of hydroelectric schemes; storage and run-of -river. Storage schemes require dams. In run-of-river schemes, turbines are placed in the natural flow of a river. Once in operation, hydro schemes emit very little CO2, although some methane emissions do arise due to decomposition of flooded vegetation. Storage schemes have a higher footprint, (~10-30gCO2eq/kWh), than run-of-river schemes as they require large amounts of raw materials (steel and concrete) to construct the dam.

v) Wind - Electricity generated from wind energy has one of the lowest carbon footprints. As with other low carbon technologies, nearly all the emissions occur during the manufacturing and construction phases, arising from the production of steel for the tower, concrete for the foundations and epoxy/fibreglass for the rotor blades. Emissions generated during operation of wind turbines arise from routine maintenance inspection trips. This includes use of lubricants and transport. Onshore wind turbines are accessed by vehicle, while offshore turbines are maintained using boats and helicopters. The manufacturing process for both onshore and offshore wind plant is very similar, so life cycle assessment shows that there is little difference between the carbon footprints of onshore (4.64gCO2eq/kWh) versus offshore (5.25gCO2eq/kWh) wind generation.

vi) Nuclear - Nuclear power generation has a relatively small carbon footprint (~5gCO2eq/kWh). Since there is no combustion, (heat is generated by fission of uranium or plutonium), operational CO2 emissions account for <1%.

Reduction of carbon footprint –

The carbon footprint can be efficiently and effectively reduced by applying the following steps:

(a) Life Cycle Assessment (LCA) to accurately determine the current carbon footprint,

(b) Identification of hot-spots in terms of energy consumption and associated CO2-emissions;

(c) Optimization of energy efficiency and, thus, reduction of CO2-emissions and reduction of other greenhouse gas (GHG) emissions contributed from production processes. Energy and resources conservation is the major way to reduce carbon footprint. ‘Reduce, Reuse and Recycle’ – should be the objective of today;  

(d) Identification of solutions to neutralize the CO2 emissions that cannot be eliminated by energy saving measures;

(e) Educate employees and general public to practice eco-friendly and green practices in day to day life, this will help lessen emission and save planet.

(f) The last important step includes carbon offsetting; investment in projects that aim at the reducing CO2 emissions, for instance bio-fuels or tree planting activities. Plant trees, plants will absorb carbon dioxide from the atmosphere through carbon sequestration and this will reduce Carbon dioxide in the atmosphere, reduce your individual carbon foot prints and reduce climate change. A tree gives direct and indirect benefit. Trees are natural sink to pollutants especially Carbon dioxide.

Kyoto protocol -

(An initiative taken by various nations to limit emission of greenhouse gases)-

During December 1997, more than 160 nations met in Kyoto, Japan, to negotiate binding limitations on greenhouse gases for the developed nations, pursuant to the objectives of the Framework Convention on Climate Change of 1992. The outcome of the meeting was the ‘Kyoto Protocol’, in which the developed nations agreed to limit their greenhouse gas (GHG) emissions, relative to the levels emitted in 1990. The goal is to lower overall emissions from six greenhouse gases (GHGs) - carbon dioxide, methane, nitrous oxide, sulfur hexafluoride, HFCs, and PFCs - calculated as an average over the five-year period of 2008-12. The objective is to achieve "stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interference with the climate system. As of November 2007, 175 parties have ratified the protocol.

1. The United Nations Framework Convention on Climate Change agreed to a set of a "common but differentiated responsibilities." The parties agreed that:

(a) The largest share of historical and current global emissions of greenhouse gases has originated in developed countries;

(b) Per capita emissions in developing countries are still relatively low, and

(c) the share of global emissions originating in developing countries will grow to meet their social and development needs.

In other words, China, India, and other developing countries were not included in any numerical limitation of the Kyoto Protocol because they were not the main contributors to the greenhouse gas emissions during the pre-treaty industrialization period. However, even without the commitment to reduce according to the Kyoto target, developing countries do share the common responsibility that all countries have in reducing emissions.

2. The developed countries commit themselves to reducing their collective emissions of six key greenhouse gases by at least 5%. As per the convention, this group target will be achieved through cuts of 8% by Switzerland, most Central and East European states, and the European Union (the EU will meet its target by distributing different rates among its member states); 7% by the US; and 6% by Canada, Hungary, Japan, and Poland. Russia, New Zealand, and Ukraine are to stabilize their emissions, while Norway may increase emissions by up to 1%, Australia by up to 8%, and Iceland 10%.

Each country’s emissions target must be achieved by the period 2008-2012. Cuts in the three most important gases – carbon dioxide (CO₂), methane (CH₄), and nitrous oxide (N₂0) - will be measured against a base year of 1990. Cuts in three long-lived industrial gases – hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulphur hexafluoride (SF₆) - can be measured against either a 1990 or 1995 baseline.

3. Experts opine, actual emission reductions would be much larger than 5%. The richest industrialized countries (OECD members) would need to reduce their collective output by about 10%, as there was backlog. While the countries with economies in transition have experienced falling emissions since 1990, this trend is now reversing. Therefore, for the developed countries as a whole, the 5% Protocol target represents an actual cut of around 20% when compared with the emissions levels that are projected for 2010 if no emissions-control measures are adopted.

Some are skeptical about the scheme. They think Kyoto as a scheme to either slow the growth of the world's industrial democracies or to transfer wealth to the third world nations. Others argue the protocol does not go far enough to curb greenhouse emissions. Many see the costs of the Kyoto Protocol as outweighing the benefits.

Despite few oppositions majority of the countries support Kyoto protocol for reduction of greenhouse gases (GHGs) and already started working in the direction of reducing the emission of greenhouse gases.

Carbon credit –

The Kyoto Protocol has created a mechanism under which countries that have been emitting more carbon and other gases of GHGs have voluntarily decided that they will bring down the level of carbon they are emitting to the levels of early 1990s; thus carbon credits are generated by enterprises in the developing world that shift to cleaner technologies and thereby save on energy consumption, consequently reducing their GHGs.

Now, a company has two ways to reduce emissions. One, it can reduce the GHG (greenhouse gases) by adopting new technology or improving upon the existing technology by attaining to the newer emission norms. Alternatively, the company may tie up with developing nations and help them set up new technology that is eco-friendly, thereby helping developing country or its companies 'earn' Credits. India, China and some other countries have the advantage because they are developing countries. Any company, factories or farm owner in India can get linked to United Nations Framework Convention on Climate Change (UNFCCC) and know the 'standard' level of carbon emission allowed for its outfit or activity. The extent to which they are emitting less carbon (as per standard fixed by UNFCCC) they get credited in a developing country. This is called ‘carbon credit’. These credits are bought over by the companies of developed countries.

Conclusion and Summary –

The greatest potential for carbon footprint reduction is in conventional fossil fuelled electricity generation, using improved combustion technologies, carbon capture and storage and co-firing with biomass. We tried to examine most the technologies available to know the potential to reduce their carbon footprint.

a. Fossil fuel generation – future carbon footprint - Technology improvements could increase the energy efficiency of existing coal fired plants from current levels of ~35% (where only 35% of the fuel energy is converted into electricity) to over 50% (by using super-critical thermal power plant). Improvements in energy efficiency can halve life cycle carbon emissions in both coal and gas fired plants. Carbon capture and storage (CCS) could potentially avoid 90% of CO2 emissions to the atmosphere in the future.

b. Co-firing fossil fuels and biomass - Co-firing biomass along side fossil fuels in existing power plants can also significantly lower their carbon emissions, because the fossil fuels are replaced by ‘carbon neutral’ biomass.

c. Future carbon footprint reductions in all technologies - Carbon footprints could be further reduced in all electricity generation technologies if the manufacturing phase and other phases of their life cycles were fuelled by low carbon energy sources. For example, if steel for wind turbines were made using electricity generated by wind, solar or nuclear plants. Using fewer raw materials would also lower life cycle CO2 emissions, especially in emerging technologies such as marine and PV. New semi-conducting materials (organic cells and nano-rods), are being researched for PV, as alternatives to energy and resource intensive silicon.

d. Future nuclear footprint & global uranium resources - Some analysts are concerned that the future carbon footprint of nuclear power could increase if lower grade uranium ore is used, as it would require more energy to extract and refine to a level usable in a nuclear reactor. Point is to be noted: if lower grades of uranium are used in the future the footprint of nuclear will increase, but only to a level comparable with other ‘low carbon’ technologies and will not be as large as the footprints of fossil fuelled systems.

Overview of future carbon footprint reduction –

(1) All electricity generation technologies emit CO2 at some point during their life cycle. None of these technologies are entirely ‘carbon free’.

(2) Life cycle inventory analysis is used to measure the amount of CO2 emitted by each technology.

(3) Fossil fuelled electricity generation has the largest carbon footprint (up to 1,000gCO2eq/kWh). Most emissions arise during plant operation.

(4) ‘Low carbon’ technologies have low life cycle carbon emissions (<100gCO2eq/kwh).>

(5) Future carbon footprints can be reduced for all electricity generation plants if high CO2 emission phases are fuelled by low carbon energy sources.

Carbon Trading scheme has been threatened by Global Recession -

Our effort to control CO2 and other greenhouse gases (GHG) faces threatened due to present ongoing global recession. It is well known that, under the Kyoto Protocol industrilised nations agreed for reduction of CO2 and other GHGs in order to mitigate global warming and climate change. Subsequently, many nations introduced Carbon Trading System, whereby Authorities put a price on the amount of GHGs that can be emitted by any company. It was hoped that, by asking companies to pay for their GHGs emission, they would be inclined to make cleanup action.

Thus, concept of issuing “Carbon Trading Permits” to various companies has started. Companies are issued emission permits as per the quota fixed for a particular industry. Companies that need to increase their emission allowance should buy credits from those who have surpluses. Effectively, the buyer is paying for polluting, while the seller is being rewarded for their reduction in emissions by more than what is needed.

Now, due to ongoing recession the demand of most commodities have fallen sharply, thus the production and pollution from most of the polluted industries such as cement, steel and glass have been less. So, companies try to bolster their faltering balance sheets by selling of their gained Carbon Trading Permits.

Strangely, that has led to, not only a big drop in the market value of Carbon Permits, the “Right to Pollute” has become cheaper as well. In other words, “Because of our faulty system”, now “There is less incentive available for companies to work towards mitigation of GHG emissions and climate change”.