Economics of tackling climate change

WHERE COST-EFFECTIVE REDUCTIONS COULD BE ACHIEVED

• These are IPCC estimates for the reductions in emissions that could be achieved cost-effectively from various sectors with a carbon price of $50 per tonne of CO2-equivalent
• Greenhouse gas emissions are given in gigatonnes (billion tonnes) of carbon dioxide-equivalent (GtCO2-eq)
• Different greenhouse gases contribute different amounts of warming per molecule; all are converted into the amount of CO2 which would give the same degree of warming, hence CO2-equivalent

Below is a guide to the key areas where the Intergovernmental Panel on Climate Change (IPCC) believes the reductions can be achieved.

BUILDINGS

Current mitigation technologies: Efficient lighting; more efficient electrical appliances/cookers; better insulation/ventilation; solar-powered heating/cooling; alternative refrigeration fluids; recovery and recycling of fluorinated gases.

Future potential for mitigation: Integrated solar photo-voltaic electricity; "smart" metering; intelligent controls.

Proven environmentally effective policies and measures: Appliance standards and labelling. Building codes and certification. Incentives for energy-service companies.

Constraints/opportunities: Periodic revision of standards required. Attractive for new buildings; enforcement can be difficult. Access to third-party financing.

Harvesting houses for the planet

'Smart-metering'

Pioneers look forward to solar future

INDUSTRY

Current mitigation technologies: More efficient electrical equipment; heat and power recovery; material recycling and substitution; control of non-CO2 gas emissions.

Future potential for mitigation: Advanced energy efficiency; CCS for cement-, ammonia- and iron manufacture; inert electrodes for aluminium manufacture.

Proven environmentally effective policies and measures: Provision of benchmark information; performance standards; subsidies/tax credits. Tradeable permits. Voluntary agreements.

Constraints/opportunities: May be appropriate to stimulate technology uptake. Stable national policy important in view of international competitiveness. Predictable allocation mechanisms and stable price signals important for investments. Success factors include clear targets; third-party involvement in design and review; formal monitoring; close co-operation between government and industry.

China gas emissions 'may pass US'

ENERGY SUPPLY

Current mitigation technologies: Improved supply and distribution efficiency; combined heat-and-power systems; switching from coal to gas; nuclear power; renewable heat and power; initial carbon dioxide capture and storage (CCS) techniques.

Future potential for mitigation: CCS for gas; biomass and coal-fired electricity generating facilities; advanced nuclear power; advanced renewables, including tidal and wave energy.

Proven environmentally effective policies and measures: Reduction of fossil-fuel subsidies; taxes/ carbon charges on fossil fuels. Feed-in tariffs for renewable-energy technologies; renewable-energy obligations; producer subsidies.

Constraints/opportunities: Resistance by vested interests may make implementation difficult. May be appropriate to create markets for low-emissions technologies.

Carbon capture and storage

Power station harnesses Sun's rays

AGRICULTURE

Current mitigation technologies: Improved land management to increase soil carbon storage; restoration of cultivated peaty soils and degraded lands; improved rice cultivation techniques/livestock and manure management to reduce methane emissions; improved nitrogen fertiliser-application techniques to reduce nitrous oxide emissions; replace fossil-fuel use with dedicated energy crops.

Future potential for mitigation: Improvements of crop yields.

Proven environmentally effective policies and measures: Financial incentives for improved land management; maintaining soil carbon content; efficiency in irrigation and use of fertilisers.

Constraints/opportunities: May encourage synergy with sustainable development and with reducing vulnerability to climate change - overcoming potential implementation barriers.

Climate change lessons in Indonesia

Climate benefits for UK farming

FORESTRY

Current mitigation technologies: Forest management, new forestation, reforestation and reduced deforestation; harvested-wood product management; use of forestry products for bio-energy to replace fossil-fuel use.

Future potential for mitigation: Tree-species improvement to increase biomass productivity and carbon sequestration; improved remote sensing technologies for analysis of vegetation/soil-carbon sequestration potential and mapping land-use change.

Proven environmentally effective policies and measures: Financial incentives to maintain and manage forests, increase forest areas and reduce deforestration; land-use regulation and enforcement.

Constraints/opportunities: Lack of investment capital; land-tenure issues. Can help poverty alleviation.

Quick Guide: Biofuels

TRANSPORT

Current mitigation technologies: More fuel-efficient/hybrid vehicles; cleaner diesel; bio-fuels; shift from road- to rail and public-transport systems; more cycling/walking; land-use and transport planning.

Future potential for mitigation: Second-generation biofuels; more efficient aircraft; advanced electric and hybrid vehicles with more powerful and reliable batteries.

Proven environmentally effective policies and measures: Mandatory fuel-economy, bio-fuel blending and CO2 standards. Taxes on vehicle purchase, registration, use and motor fuels; road- and parking-pricing. Influence mobility needs through land-use regulations and infrastructure planning; investment in attractive public transport and non-motorised forms.

Constraints/opportunities: Partial coverage of vehicle fleet may limit effectiveness. Effectiveness may drop with higher incomes. Particularly appropriate for countries building up their transportation systems.

Biofuels: The next generation

WASTE

Current mitigation technologies: Landfill methane recovery; waste incineration with energy recovery; composting of organic waste; controlled waste-water treatment; recycling; waste minimisation.

Future potential for mitigation: Biocovers and biofilters to optimise methane oxidation.

Proven environmentally effective policies and measures: Financial incentives for improved waste and waste-water management. Renewable-energy incentives or obligations. Waste-management regulations.

Constraints/opportunities: May stimulate technology diffusion. Local availability of low-cost fuel. Most effectively applied at national level with enforcement strategies.

Global methane rise slowing down