Technological solutions
Big idea: Technology can reduce emissions at the source — through cleaner vehicles, improved industrial processes, and cleaner energy generation.
Vehicle technologies
- Catalytic converters: Convert CO, NOₓ, and hydrocarbons to less harmful gases — required on petrol cars since 1970s/80s
- Particulate filters: Trap soot from diesel exhausts
- Electric vehicles (EVs): Zero tailpipe emissions (but electricity source matters)
- Hybrid vehicles: Combine engine and electric motor for better efficiency
- Hydrogen fuel cells: Zero emissions; water is only byproduct
Industrial and energy technologies
- Scrubbers: Remove SO₂ and particulates from power plant emissions
- Electrostatic precipitators: Remove particulates using electrical charge
- Low-NOₓ burners: Reduce nitrogen oxide formation during combustion
- Fuel switching: Move from coal to natural gas or renewables
- Carbon capture: Remove CO₂ (primarily for climate, but some co-benefits)
Domestic solutions
- Clean cookstoves: Reduce indoor air pollution from biomass burning
- Efficient heating: Modern boilers, heat pumps, insulation
- Cleaner fuels: Switch from coal/wood to gas or electricity
Exam tip: Technological solutions are often favoured by technocentric EVSs. Be ready to evaluate their effectiveness AND limitations (cost, rebound effects, addressing symptoms not causes).
Policy and behavioural approaches
Big idea: Regulations, economic incentives, and behaviour change can complement technology by reducing emissions and encouraging cleaner choices.
Regulatory approaches
- Emission standards: Set limits on what vehicles and industry can emit
- Air quality standards: Define acceptable pollution levels (WHO guidelines, national standards)
- Vehicle restrictions: Low emission zones (LEZs), congestion charging, car-free days
- Industrial permits: Require pollution control as condition of operating
- Fuel quality standards: Mandate low-sulfur fuels, ban leaded petrol
Economic instruments
- Congestion charges: Fee for driving in city centres (London, Singapore, Stockholm)
- Pollution taxes: Tax on emissions or polluting fuels
- Subsidies: Support for EVs, public transport, clean technology
- Scrappage schemes: Incentives to replace old, polluting vehicles
- Cap and trade: Market-based limits on industrial emissions
Behavioural and planning approaches
- Public transport investment: Provide alternatives to private cars
- Cycling and walking infrastructure: Safe routes, bike-sharing schemes
- Urban planning: Mixed-use development reduces travel; green spaces improve air quality
- Awareness campaigns: Educate public about pollution and health
- Remote working: Reduce commuting (accelerated by COVID-19)
Londons congestion charge reduced traffic by 30% and improved air quality in the charging zone. Economic instruments can be highly effective.
Exam tip: Compare TECHNOLOGICAL vs BEHAVIOURAL approaches. Technocentrists favour technology; ecocentrists often prefer demand reduction and behaviour change.