Climate Mitigation to 2030 (excerpts from IPCC 4th Report, WG III, Summary for Policy Makers)
Both bottom-up and top-down studies indicate that there is substantial economic potential for the mitigation of global GHG emissions over the coming decades, that could offset the projected growth of global emissions or reduce emissions below current levels.
1. Changes in lifestyle and behaviour patterns can contribute to climate mitigation to 2030 across all sectors. Management practices can also have a positive role.
Lifestyle changes can reduce GHG emissions. Changes in lifestyles and consumption patterns that emphasize resource conservation can contribute to developing a low-carbon economy that is both equitable and sustainable.
Education and training programmes can help overcome barriers to the market acceptance of energy efficiency, particularly in combination with other measures.
Changes in occupant behaviour, cultural patterns and consumer choice and use of technologies can result in considerable reduction in CO2 emissions related to energy use in buildings.
Transport Demand Management, which includes urban planning (that can reduce the demand for travel ) and provision of information and educational techniques (that can reduce car usage and lead to an efficient driving style) can support GHG mitigation.
In industry, management tools that include staff training, reward systems, regular feedback, and documentation of existing practices can help overcome industrial organization barriers, reduce energy use, and GHG emissions.
2. While studies use different methodologies, in all analyzed world regions near-term health co-benefits from reduced air pollution as a result of actions to reduce GHG emissions can be substantial and may offset a substantial fraction of mitigation costs.
Including co-benefits other than health, such as increased energy security, and increased agricultural production and reduced pressure on natural ecosystems, due to decreased tropospheric ozone concentrations, would further enhance cost savings.
Integrating air pollution abatement and climate change mitigation policies offers potentially large cost reductions compared to treating those policies in isolation.
3. New energy infrastructure investments in developing countries, upgrades of energy infrastructure in industrialized countries, and policies that promote energy security, can, in many cases, create opportunities to achieve GHG emission reductions compared to baseline scenarios. Additional co-benefits are country- specific but often include air pollution abatement, balance of trade improvement, provision of modern energy services to rural areas and employment.
Future energy infrastructure investment decisions, expected to total over 20 trillion US$ between now and 2030, will have long term impacts on GHG emissions, because of the long life-times of energy plants and other infrastructure capital stock. The widespread diffusion of low-carbon technologies may take many decades, even if early investments in these technologies are made attractive. Initial estimates show that returning global energy-related CO2 emissions to 2005 levels by 2030 would require a large shift in the pattern of investment, although the net additional investment required ranges from negligible to 5-10%.
It is often more cost-effective to invest in end-use energy efficiency improvement than in increasing energy supply to satisfy demand for energy services. Efficiency improvement has a positive effect on energy security, local and regional air pollution abatement, and employment.
Renewable energy generally has a positive effect on energy security, employment and on air quality. Given costs relative to other supply options, renewable electricity, which accounted for 18% of the electricity supply in 2005, can have a 30-35% share of the total electricity supply in 2030 at carbon prices up to 50 US$/tCO2-eq.
The higher the market prices of fossil fuels, the more low-carbon alternatives will be competitive, although price volatility will be a disincentive for investors. Higher priced conventional oil resources, on the other hand, may be replaced by high carbon alternatives such as from oil sands, oil shales, heavy oils, and synthetic fuels from coal and gas, leading to increasing GHG emissions, unless production plants are equipped with Carbon Capture and Storage (CCS).
Given costs relative to other supply options, nuclear power, which accounted for 16% of the electricity supply in 2005, can have an 18% share of the total electricity supply in 2030 at carbon prices up to 50 US$/tCO2-eq, but safety, weapons proliferation and waste remain as constraints.
CCS in underground geological formations is a new technology with the potential to make an important contribution in climate mitigation to 2030. Technical, economic and regulatory developments will affect the actual contribution.
4. There are multiple climate mitigation to 2030 options in the transport sector, but their effect may be counteracted by growth in the sector. Mitigation options are faced with many barriers, such as consumer preferences and lack of policy frameworks.
Improved vehicle efficiency measures, leading to fuel savings, in many cases have net benefits (at least for light-duty vehicles), but the market potential is much lower than the economic potential due to the influence of other consumer considerations, such as performance and size. There is not enough information to assess the mitigation potential for heavy-duty vehicles. Market forces alone, including rising fuel costs, are therefore not expected to lead to significant emission reductions.
Biofuels in climate mitigation to 2030 might play an important role in addressing GHG emissions in the transport sector, depending on their production pathway. Biofuels used as gasoline and diesel fuel additives/substitutes are projected to grow to 3% of total transport energy demand in the baseline in 2030. This could increase to about 5-10%, depending on future oil and carbon prices, improvements in vehicle efficiency and the success of technologies to utilise cellulose biomass.
Modal shifts from road to rail and to inland and coastal shipping and from low-occupancy to high occupancy passenger transportation, as well as land use, urban planning and non-motorized transport offer opportunities for GHG mitigation, depending on local conditions and policies.
Medium term mitigation potential for CO2 emissions from the aviation sector can come from improved fuel efficiency, which can be achieved through a variety of means, including technology, operations and air traffic management. However, such improvements are expected to only partially offset the growth of aviation emissions. Total mitigation potential in the sector would also need to account for non-CO2 climate impacts of aviation emissions.
Realizing emissions reductions in the transport sector is often a co-benefit of addressing traffic congestion, air quality and energy security.
5. Energy efficiency options19 for new and existing buildings could considerably reduce CO2 emissions with net economic benefit. Many barriers exist against tapping this potential, but there are also large co-benefits.
By 2030, about 30% of the projected GHG emissions in the building sector can be avoided with net economic benefit.
Energy efficient buildings, while limiting the growth of CO2 emissions, can also improve indoor and outdoor air quality, improve social welfare and enhance energy security.
Opportunities for realising GHG reductions in the building sector exist worldwide. However, multiple barriers make it difficult to realise this potential. These barriers include availability of technology, financing, poverty, higher costs of reliable information, limitations inherent in building designs and an appropriate portfolio of policies and programs.
The magnitude of the above barriers in climate mitigation to 2030 is higher in the developing countries and this makes it more difficult for them to achieve the GHG reduction potential of the building sector.
6. The economic potential in the industrial sector is predominantly located in energy intensive industries. Full use of available climate mitigation to 2030 options is not being made in either industrialized or developing nations.
Many industrial facilities in developing countries are new and include the latest technology with the lowest specific emissions. However, many older, inefficient facilities remain in both industrialized and developing countries. Upgrading these facilities can deliver significant emission reductions.
The slow rate of capital stock turnover, lack of financial and technical resources, and limitations in the ability of firms, particularly small and medium-sized enterprises, to access and absorb technological information are key barriers to full use of available mitigation options.
7. Agricultural practices collectively can make a significant contribution at low cost to increasing soil carbon sinks, to GHG emission reductions, and by contributing biomass feedstocks for energy use.
A large proportion of the mitigation potential of agriculture (excluding bioenergy) arises from soil carbon sequestration, which has strong synergies with sustainable agriculture and generally reduces vulnerability to climate change.
Stored soil carbon may be vulnerable to loss through both land management change and climate change.
Considerable mitigation potential is also available from reductions in methane and nitrous oxide emissions in some agricultural systems.
There is no universally applicable list of mitigation practices; practices need to be evaluated for individual agricultural systems and settings (e.g.soil tillage ).
Biomass from agricultural residues and dedicated energy crops can be an important bioenergy feedstock, but its contribution to climate mitigation to 2030 depends on demand for bioenergy from transport and energy supply, on water availability, and on requirements of land for food and fibre production. Widespread use of agricultural land for biomass production for energy may compete with other land uses and can have positive and negative environmental impacts and implications for food security.
8. Forest-related climate mitigation to 2030 activities can considerably reduce emissions from sources and increase CO2 removals by sinks at low costs, and can be designed to create synergies with adaptation and sustainable development.
About 65% of the total climate mitigation to 2030 potential (up to 100 US$/tCO2-eq) is located in the tropics and about 50% of the total could be achieved by reducing emissions from deforestation.
Climate change can affect the mitigation potential of the forest sector (i.e., native and planted forests) and is expected to be different for different regions and sub regions, both in magnitude and direction.
Forest-related mitigation options can be designed and implemented to be compatible with adaptation, and can have substantial co-benefits in terms of employment, income generation, biodiversity and watershed conservation, renewable energy supply and poverty alleviation.
9. Post-consumer waste is a small contributor to global GHG emissions25 (<5%), but the waste sector can positively contribute to climate mitigation to 2030 at low cost and promote sustainable development.
Existing waste management practices can provide effective mitigation of GHG emissions from this sector: a wide range of mature, environmentally effective technologies are commercially available to mitigate emissions and provide co-benefits for improved public health and safety, soil protection and pollution prevention, and local energy supply.
Waste minimization and recycling provide important indirect climate mitigation to 2030 benefits through the conservation of energy and materials
10. Geo-engineering options, such as ocean fertilization to remove CO2 directly from the atmosphere, or blocking sunlight by bringing material into the upper atmosphere, remain largely speculative and unproven, and with the risk of unknown side-effects. Reliable cost estimates for these climate mitigation to 2030 options have not been published.