2015 - Past Paper Questions Flashcards
Explain what is meant by Carbon Capture and Storage (CCS) from fossil fuel plants.
Carbon Capture and Storage (CCS) is the name given to the technology and process designed to prevent carbon dioxide exhaust produced when burning fossil fuels from entering the atmosphere [1].The exhaust gas from the combustion of fossil fuels is ‘captured’ and then ‘stored’ rather than being released into the atmosphere [1]
Outline the three main phases of Carbon Capture and Storage and the processes involved with each
- Phase 1: Trapping and separating [1] entails taking the gas emitted from the process and separating CO2 from the other gases which are present [1].
- Phase 2: Transporting [1] involves moving the isolated CO2 to a location for its storage normally through a system of pipes [1].
- Phase 3: Storage [1] refers to the long term location for the captured gas. Currently this is done either underground or underwater [1].
Discuss one advantage and one risk of Geo engineering to offset the effects of climate change
Any one advantage from:
• Counteract increasing global temperatures • Facilitates the control of greenhouse gases • Counteracts climate change • Some technologies (e.g. cool roof technologies) are inexpensive and effective.
Any one risk from:
• Risks associated with control and predictability of technologies and processes • Little known about the long term side effects • Ethical concerns and risks associated with the use of geo-engineering • Governance risks
Outline the operational purpose of an Attenuator Type Device
Attenuator: These devices are oriented parallel to the direction of the wave [1].
Attenuators are typically a series of long cylindrical floating devices connected to each other with hinges and anchored to the seabed (Pelamis) [1].
The cylindrical parts drive hydraulic rams in the connecting sections [1] and those in turn drive an electric generator [1].
The devices send the electricity through cables to the sea floor where it then travels through a cable to shore [1].
Describe three environmental implications that must be considered when deciding to install wave energy converters at a particular site
Any three from: • Impact on marine life and habitat • Risk of toxic pollution • Visual and noise impact • Conflict with other sea users
Compare and Contrast Tidal Stream Generators and Tidal Barrages
Tidal stream generators make use of the kinetic energy of moving water to power turbines [1]. Tidal barrages make use of the potential energy in the difference in water height between high and low tides [1]. With the receding tide, this potential energy is then converted into kinetic energy as the water is released through large turbines that create electrical power through the use of generators [1].
Tidal stream generators have the advantage of being much cheaper to build [1], and do not have as much of an environmental impact as a tidal barrage [1].
Name and describe three approaches required by todays society if One Planet living is to be achieved
Any three from:
• Zero carbon [1] Making buildings more energy efficient and delivering all energy with renewable technologies [1].
• Zero waste [1] Reducing waste, reusing where possible, and ultimately sending zero waste to landfill [1].
• Sustainable transport [1] Encouraging low carbon modes of transport to reduce emissions, reducing the need to travel [1].
• Sustainable materials [1] Using sustainable healthy products, with low embodied energy, sourced locally, made from renewable or waste resources [1].
• Local and sustainable food [1] Choosing low impact, local, seasonal and organic diets and reducing food waste [1].
• Sustainable water [1] Using water more efficiently in buildings and in the products we buy; tackling local flooding and water course pollution [1].
• Land use and wildlife [1] Protecting and restoring biodiversity and natural habitats through appropriate land use and integration into the built environment [1].
• Culture and community [1] Reviving local identity and wisdom; supporting and participating in the arts [1].
• Equity and local economy [1] Creating bioregional economies that support fair employment, inclusive communities and international fair trade [1].
• Health and happiness [1] Encouraging active, sociable, meaningful lives to promote good health and well-being [1].
Define and Explain the concept and measurement of an ecological footprint
An ecological footprint is based on consumption over a specific year [1]. Expressed as the amount of land and sea (bio-productive area) required to support the use of natural resources [1]. A means of comparing usage of natural resources and lifestyles, and checking this against nature’s ability to provide for this [1].
Describe two measures that can be taken to improve the energy efficiency of the outside wall
Any two from:
• Adding additional insulation (Internal/External/Cavity) to the external wall will improve energy efficiency [1]
• Improved glazing (double/triple/Low E) will improve energy efficiency of the room [1]
• Improving airtightness around windows and openings will mean the building is more energy efficient [1]
State one environmental benefit of installing insulation
Environmental benefits: Any one from:
• reduced carbon emissions
• increased levels of home comfort
• reducing likelihood of condensation and mildew
What are the three stages of Zero Carbon Homes Hierarchy
Allowable Solutions [1]
On site low/zero carbon heat and power [1]
Fabric Energy Efficiency [1]
Explain two core requirements for a Zero Carbon Home
Any two from:
• The fabric performance must, at a minimum, comply with the Fabric Energy Efficiency Standard (FEES) [1]
• Any CO2 emissions that remain after consideration of heating, cooling, fixed lighting and ventilation, must be less than or equal to the Carbon Compliance limit established for zero carbon homes [1]
• Any remaining CO2 emissions, from regulated energy sources (after requirements 1 and 2 have been met), must be reduced to zero [1]
Discuss the advantages and disadvantages of recovering energy from waste to incineration. Specific reference to
Environmental Issues
Economic Issues
Security of Supply
Environmental Issues
• Reduces volume of waste sent to landfill significantly (by approx. 90%)
• There is a negative public perception about the emissions and the technologies involved (NIMBY) – Not In My Back Yard
• Residue from flue gas treatment process or from bottom ash may go to landfill as hazardous waste
• Stack emissions (flue gases) can be treated to by ‘scrubbing’ or filtering or electrostatic precipitation
Economic Issues
• Incineration plants can generate lots of electricity and can also provide local district heating (especially if close to urban areas)
• Energy from waste reduces the amount of landfill tax that has to be paid by business
• Bottom ash residue may be recycled for building materials
• Incineration plants are costly and so need high utilisation to be cost-effective
Security of Supply Issues
• To be effective energy from waste plants need a secure supply
• Minimum or guaranteed tonnage may be needed by operator to cover costs
• Risks to supply due to increased exports of waste to countries with lower gate fees
• Risks to supply due to illegal activity regarding gate fees
