L4 Flashcards
What are demand sectors?
Energy sectors are those that receive final energy from the supply sector and convert this into useful energy to meet an energy service demand
energy service demand eg. mobility and thermal heating
What are some examples of demand sectors?
Industry
Transport
Buildings
Agriculture
Which is the most/least CO2 intensive demand sector?
Most
1. electricity and heat
2. transport
3. manufacturing and construction
Least
Fugitive emissions
What are fugitive emissions?
emissions are leaked during refinary and other processes
Can you speak to the energy flow to transport?
11/121 of transports energy fuel is coming from the oil sector
crude oil is transformed into petrol, diesel or jet fuel
but electrical cars might see a shift into the future
Can you speak to the industrial sectors energy mix?
Largest sector for consumption of energy but energy mix is v diverse
consumes both electricity and heat
Oil, coal, natural gas and biomass
Can you talk to the geographic distribution of final energy demand and the sectors within that geographic distribution?
China - high exporting nation - China has the highest consumption and it is mainly in industry
US is the second highest consumer of final energy demand and majority of it is in transport
What has GDP got to do with it?
- As GDP increases agriculture demand for final energy decreases, services and manufacturing increase in demand for final energy
= idea of a transition in economies that drives energy demand
Manufacturing consumes a lot of energy - service energy also demanding of energy - IT services and transport
What is the kaya identity equation?
CO2 emissions = Pop x GDP/pop x Energy/GDP x Co2/energy
What impact does GDP/Pop have?
gdp is a driver
require more energy as it goes up so you are increasing Co2
What impact does Energy/GDP have?
This describes the energy intensity -value adding in the GDP
how much energy are you consuming and how efficiency is the energy
developed countries have a better energy intensity thus have better value - smaller amount of energy to get the same amount of GDP
What impact does CO2/Energy have?
this describes the emissions intensity
= how much emission is producer per energy energy produced
What is the equation for decomposition analysis of emissions?
CO2 = demand x structure x energy efficiency x fuel mix x emissions intensity
demand = sum of total activity of subsector and fuel type
structure = Sub-sector activity /total activity
Energy efficiency = Sub-sector energy/ sub-sector activity
Fuel mix = subsector fuel type/ subsector energy
Emissions intensity = emissions from fuel type/ fuel type
What has been responsible for reduced growth rate in the last decade?
decarbonisation and decline in energy per GDP
Covid - 19 = less activity = less emissions
- reduced industry, land transport and minimal aviation reduction in daily emissions 2019vs 2020
How much of final energy demand / emissions is from transport?
30% final energy demand
15% of global emissions
What is avoid/reduce, shift and improve?
Avoid/reduce = reduce demand in the first place.
Shift= moving from a less sustainable method of consumption to a more sustainable method.
Improve = improving the efficiency of the existing technology i.e. emissions intensity of energy efficiency
Can you give some examples of avoid/reduce, shift and improve in the transport industry?
Transport industry is providing a service of accessibility and mobility
Avoid
- integrate transport and land-use planning
- smart logistics
- teleworking
- compact cities
Shift
- mode shift from car to cycling, walking or public transit
Improve
- electric vehicles
- eco-driving
- smaller, lightweight vehicles
Can you give some examples of avoid/reduce, shift and improve for buildings?
Buildings provide shelter as a service
Avoid
- passive house or retrofit - avoiding demand for heating and cooling
- change temperature set-points
Shift
- heat pumps, district heating and cooling
- combined heat and power
Improve
- consensing boilers
- incremental insulation options
-energy-efficient appliances
Can you give some examples of avoid, shift and improve for manufactured products and services?
Provides a service of clothing and appliances
Avoid
- long-lasting fabrics, appliances, sharing economy
- eco-industrial parks
-circular economy
Shift
- shift to recycled materials
- low-carbon materials for buildings and infrastructure
Improve
- use of low-carbon fabrics
- new manufacturing processes and equipment use
For transport can you use the decomposition of equation to come up with options of how to improve co2 emissions?
Activity/transport demand
- reducing the number of journeys or the distance
eg, increasing the density of urban landscapes
- sourcing localised products
-optimised logistics systems
-ICT conferencing
Systems-infastructure and modal choice
- switching to lower carbon modes of transport
eg. public transport, walking or cycling
Energy Intensity
- improving energy efficiency
- enhanced vehicle and engine performance
- lightweight materials
Fuel switching
- to lower carbon fuels
eg. petrol to biofuel or increased electrification
Emissions Intensity
- decarbonisation of the electricity sector
- increasing sustainability of biofuels
What factors influence transport trends?
Travel time budgets - the average amount of time per day that a person spends commuting
- independent of wealth, race or geography
1.1-1.3 hours travelled per day
speed of travel dictates the range
security, speed and travel/waiting time
What is the relationship between economic growth and car ownership?
Increases in income increase car ownership
but this doesn’t translate into car usage
about status, freedom and flexibility rather than usage - can change the tech but changing the ownership would be more difficult
What are some of the considerations that need to be taken when considering improving technology?
- occupancy load of the technology
the carbon footprint of travel per kilometer is vastly different for a domestic flight, long haul flight and national rail - have to understand the co-benefits eg. public transport is v important for poorer populations
Can you speak to some considerations required for a modal shift in passenger travel?
- Heavily dependent on behavioural change and infrastructure
- deliberate and considered urban planning can have a significant positive impact –> penalising or incentivising eg. London congestion charge or EV vehicle charging infrastructure
e.g. public bike sharing schemes and cycle lanes - around 15% of current journeys can be replaced by walking or cycling - IPCC
- high speed rail <800km can be a substitute for long distance road or short haul flights
= energy p-km can be 65-80% less than air travel - significant co-benefits
Can you speak to the considerations that need to be taken for a model shift in freight?
- current trend is away from rail and shipping towards air and road
- 70% growth in truck travel between 2010-2050 is expected - this trend needs to be reversed
- European commissions has set a target for all frieght to be >300km to be by rail/ship by 2030
–> This would require a doubling of rail capacity - switching from aviation to shipping often limited by the time-sensitivity of delivery
time is v sensitive in this industry - idea of just in time production and next day delivery
Freight has to compete with passengers
What is the potential improvements that can be made in light duty vehicles (ie.vans) ?
50% improvements by 2030 relative to 2005
redesigning to bring them in line with the best in class
i.e. direct fuel injection, automated transmissions and more gears
What are the improvements that can be made in internal combustion engines?
potential 35% more efficient
improved aerodynamics, auxiliary components, rolling resistance and weight reduction
BUT we need to move away from FF not simply reduce combustion - efficiency gains in internal combustion engines are insufficient
What is the trend in car energy efficiency globally?
the EU have the most efficieny cars - due to standards
act as a comparison mechanism for other countries
if car manufacturers cannot meet the standards they have to take the car off the market
range of affordability and leakage of best process to not all markets
What are the three main vehicle technologies?
Plug in hyrbid electric vehicles
battery electric vehicles
hydrogen fuel cell vehicles
What are the characteristics of a plug-in hybrid EV?
- have an internal combustion engine + a battery which can be recharged by connecting to the grid
- 50-150km on battery
- reduces fuel consumption by up to 45% = consume less energy and electricity from a to b
- drop in battery costs - more affordable but people want a fancy car
What are the characteristics of a battery electric vehicle?
- 2x more efficient than internal combustion engine
- could reach cost-parity with petrol/disel by 2020
- rapid reduction in costs of batteries - li-ion
- extending range on battery 500km
What are the characteristics of a hydrogen cell vehicle?
-1.5x more efficient that an internal combustion engine
-limited by hydrogen infrastructure and refilling requirements - expensive due to gas and compression - sufficient infrastructure at appropriate distances
- more likely to be used for heavy trucks
but potential that it will increase the weight of the vehicles
Where could hydrogen play a role in transport?
where the need for energy dense fuels means that batteries are not a good option
ie. in long-distance transport, shipping and aviation
when you are not connected to the grid and cannot rely on the grid when the battery runs out
but volume is a big problem for hydrogen
What are the issues with hydrogen in long-distance road transport?
- compeittion with electrification - batteries are dominating road transport
-hydrogen vehicles are more expensive and complex than EVs
but some long distance transport could use it
What are some of consideratoins of hydrogen vs electrification in shipping?
- energy density of batteries are not good enough for long-distance shipping
- hydrogen - probably being stored and burned as ammonia rather than H2 - direct = could play a role here.
What are some of the limitations associated with using hydrogen for aviation?
The volumentric energy densityof H2 is poor = hard to fit enough hydrogen onto the plane
H2 takes up to 10x more space - would have to redesign planes
more likely to use H2 to produce synthetic kerosene and burn this instead
Is there potential to blend biofuels with ICE?
ethonol and biofules can be blended at low levels - 10-15% with petroleum fuels and used in unmodified ICEs
at low cost ICE can be modified during manufacture to accommodate higher blends - flex fuel engines can have up to 85%-100%
BUT
lifecycle emissions and broader impacts area. concern
What are some of the co-benefits of mitigation in the transport sector?
- Health benefits of reduced vehicle exhaust emissions
- health benefits of increased human activity through walking and cycling
- reduced noise
-road transport is higher risk than other forms of transport and was responsible for 1.35 m deaths per year globally in 2016 - reduced traffic congestion if modal shifts
- improved public transport improves mobility for the poor
How many Gt of CO2 does the aviation sector produce and what is this as a percentage of emissions?
1 Gt
~2.5% of global emissions
emissions are growing fast - around 4-5% per year
Why is the climate impact larger for aviation?
non-co2 effects are high
high hydrogen and ammonia - increase the Nox
denitrification might be required - externality
if you use ammonia to reduce the Co2 and NOx level but are you just generating another problem
trade-offs and negative costs to these options
What are the potential technological improvements to mitigate Co2 in avaition
- efficiency improvements and new aircraft designs - eg. blended wing - could improve efficiency by up to about 30% compared to today
How could alternative fuels help to mitigate Co2 in aviation?
- Biofuels - but lifecycle emissions
- synthetic hydrocarbons from renewable energy
- hydrogen and ammonia - but energy density per unit volume and negative externalities and trade offs
- full electric - but energy density and weight
How much final energy demand and global emissions are from buildings?
30% final energy demand
17$ of global emissions
What are the three components of the SER framework
Efficiency = imprpving energy and material intensity –> takes into account planetary boundaries
sufficiency = avoiding the demand for energy and materials over the lifecycle of buildings and goods –> takes into account global standard of living
renewables = reducing environmental impacts of the demand for energy and materials
How is sufficiency defined>
avoiding the demand for materials, energy, land, water and other natural resources while delivering a decent living standard for all within the planetary boundaries
What does applying sufficiency principles to building require?
i. optimising the use of buildings
ii. repurposing unused existing ones
iii. prioritising multi-family homes over single-family buildings
iv. adjusting the size of buildings to the evolving needs of households by downsizing dwellings
How is energy used in buildings?
Cold cliamte - 70% for heating and appliances
hot climate - 68% for cooking and water heating
What are some of the interactions to consider in buildings?
Cement requirements
required land for houses
energy to meet demands
materials to build the house
water and other resources
What are some of the drivers for energy demand in housing?
number of houses
space - area per person increases, demand increases
number of people in the house
commercial or residential
heating or cooling requirements
What is the relationship between GDp and appliances?
Strong correlation
- income and ownerships
In OECD countries appliance ownership is approaching saturation but in developing countries still low particularly in rural areas
more income, more devices more energy
What is a building envelope?
determines the amount of energy reuqired to heat or cool a building
What is the potential energy efficiency improvements in existing stock and new builds?
Existing stock - retrofit
e.g. insulation for building block
or green cover plant roofs and climbers to cool the building
reduce demand for heat and cooling
new builds
2/3 of countries lack mandatory building codes in 2020
more than 3.5 billion m2 were built last year without mandatory energy related performance requirements
What are the energy savings from a high performance building envelope compared to an average OECD building today?
20-30% reduction in energy for heating
10-40% reduction in energy for cooling
What are the potential technologys for improving a building envelope for walls?
-Cavity insulation
- exterior insulation like cladding
- reflective wall coatings in hot climates
- proper air sealing
What are the key technologies that can be used in windows and doors?
- double galzing
- vaccum glazing
- shading attachements
-window films
-dynamic solar control
-well-sealing frames to reduce air leakage
What are the key technologies to improve building envelope for roofs?
- highly reflective surfaces in hot climates eg. gree roofs
- proper sealing is key to reduce air leakage
- integrating SPVS
What potential does LEDs have to improve energy efficiency of lightbulbs?
> 40% reduction is possible
What potential does high performance efficiency improvements have for appliances and what is an example?
eg. high performance insulation in refridgerators
- available and low cost = efficiency improvement up to 30%
What are some of the challenges associated with improving the energy efficiency of cooking?
affordability is key
- potential to shift away from biomass cooking to reduce energy demand and its negative impacts
What are three options for heating homes?
Heat-pumps
Hydrogen
heat networks
How do heat pumps work? what are the challenges?
opposite of a refridgerator - takes large amounts of ambient heat from outside, compresses it and transfers it to the inside
300-500% effcicncey
Challenges
- higher cost
- requires a retrofit
- issues in peak demand
How can hydrogen be used for heating homes and what are the challenges?
Convert exitisting boilers to run off hydrogen
Reduce disruption in the home
Challenges:
- less efficient than heat pumps
- requires a significant amount of H2
- requires new infrastructure
How do heat networks work and what are the challenges associated?
District heating - often uses waste heat from power plants and other sources
heat is piped from a local source to individual homes
more efficient than local boilers
Challenges:
- need to find a zero-carbon heat to power networks
What is biomass made up of and what are the issues associated with its use?
Wood, charcoal and dung - 60% of final energy used in developing countries
mainly for cooking but also space and water heating
issues
- v low efficiency
- negative impacts –> poor indoor air quality, deforestation and time intensity of wood collection
How much of final energy demand is in Industry and how much of global emissions does it make up?
Industry = 38% offinal energy demand
35% of global emissions
15% process emissions - e.g chemicals processes - v. difficult to change and reduce
55% direct emissions
30% indirect emissions
What are some options to reduce demand in industry?
- reducing the overall demand for product services - eg. reducing the amount we consume - requires behavioural change and customer consciousness
- use products more intensively
- reduce the amount of waste products i.e. reduce packaging
- delivering the same produce service with fewer products i.e increasing the lifetime of products through repaid and maintenance - improve material efficiency
- reduce production losses
- resue old materials - behavioural change
- improve produce design i.e. lightweight cars w/o loss in performance
How would you influence strucutre in industry to reduce co2 emissions?
Shifting from energy intensive sectors to less energy intensive sectors
i.e. shift away from cement to less energy-intensive products
different production processes
How would you improve the energy efficiency in the building sector?
reduce the required input of energy while still producing the same product
- product specific options
-cross-cutting options
How would you improve the fuel mix in industry?
Increased electrification
switching from coal to gas where possible
switching to biomass and waste
How woudl you improve the emissions intensity in industry?
- decarbonisation of the electricity sector
- CCUS
- sustainable biomass
what are some of the challenges associated with industrial decarbonisation?
- Heterogenous sector
- high temperatures requires in processes - relying currently on the direct burning of fuels to reach this temperature
- process emissions from chemical processes - electrification will not address these issues
- competitiveness and risk of leakage - need to be price competitive
What is carbon leakage
the concern that as a result of stringent climate policies companies move their production abroad to countries with less ambitious climate measures, which can lead to a rise in global ghg emissions
What are the process specific options for industry?
improve processes design, phase out inefficient technologies or heat recovery/integration processes
- highly dependent on the manufacturing process
- can result in a step-change improvement in energy efficiency
-often involves a large capital outlay
What are cross-cutting options for industry
improvements to ancillary equipment like utilities such as compressed air, steam systems and motor driven systems
requires a system-based approach
typically incremental improvements
smaller capital investments
What are the three fuel switching options for industry?
-Electricity
-Hydrogen
-Biomass
What are the pros and cons of electricity in industry?
- achieve v high efficiency - heat pumps 100%
- 78% of european industry is electrifiable
- requires low cost decarbonised electricity
- may require entire process redesign
What are the pros and cons of hydrogen in industry?
- some processes still require fuel to combust
- promising option for high temperature heat
- infrastructure and supply are key barriers
What is the potentail for biomass in industry?
- used in industrial sector already - eg. cement
- if combined with CCS could facilitate negative emissions
- barriers are life-cycle emissions and scale of supply
What are the pros and cons of CCS in industry?
Challenges
- wide range of CO2 sources
- add on tech which adds costs and energy penalty
- challenging to have a successful deployment
- impurities in flue gas
- heat integration for CCS is complex
Advatnages
- potential for clustering
- some high purity Co2 sources - v easy
- industrial sites - v large stationary sources
What would zer-carbon look like for steel?
- recycling using electric furnices
- CCS applied to blast furnices
-hydrogen-based production
What would zero-carbon look like for chemicals?
- bio-based plastics
-hydrogen feedstocks with captured Co2 - electricity for hydrogen for energy
What would zero-carbon look like for cement?
-100% waste fired kilns
- advanced CCS options such as calcium lopping
-electric kilns
-novel chemicals
