Living Carbon Free – Exploring what a net-zero target means for households
The Committee on Climate Change (CCC) is assessing the impact of a target to reach net zero emissions. In the report attached Energy Systems Catapult considers the implications for households of increased ambition across six activities: heat, transport, electricity use, aviation, diet and waste.
For each activity, they explore possible actions for decarbonisation and, using pathways set out by the CCC, they show the emissions reduction that can be achieved under different ambition levels. They also share some illustrations of what a net zero future might look like for different groups.
Heat decarbonisation will require improvements to the fabric of our homes and adoption of low carbon heating systems such as heat pumps, district heating and hydrogen boilers. Smart control systems can ensure these solutions provide the experience households want, while local area planning will be essential to ensure a joined-up approach and avoid unnecessary cost.
Transport emissions can be reduced firstly by reducing overall distances travelled (e.g. through flexible working). Shifting to more sustainable modes of transport like buses and trains, or walking and cycling, would reduce energy use by private cars (and ease congestion and improve air quality). Making more efficient use of cars would help too, e.g. through carpooling. Finally, switching to electric (and potentially hydrogen) vehicles will be essential for net zero.
Electricity use for lighting and appliances (and heat and transport) will have to be fully decarbonised. That will require national solutions like large-scale renewables, nuclear, or gas with carbon capture and storage (CCS). But there will also be significant opportunities for households to participate and provide flexibility to the grid, e.g. through micro-generation and energy storage technologies, or smart appliances that offer demand side response as part of a future smart grid.
Aviation emissions have been steadily increasing over recent decades. Airlines can help curb emissions through more efficient aircraft and flight management, and accelerating deployment of advanced technologies like hybrid electric planes. Households can contribute by thinking more carefully about our growing demand for air travel (especially the most frequent flyers).
Diet change can help reduce emissions from agriculture, in addition to ‘upstream’ changes like improved farming practices. Reducing our meat and dairy consumption can have a particularly large impact due to the high global warming effect of the methane emissions involved.
Waste reduction, including food waste, can also help to avoid emissions arising from landfill. T
To meet an 80% target, most scenarios require high ambition on electricity and waste, but many households might still be reliant on (hybrid) petrol cars and gas boilers, eat as much meat and dairy as today, and fly more every year.
Achieving net zero will require households to engage more profoundly in the transition around heat, transport, aviation and diet. This is a challenge but also an opportunity: many of the actions would have co-benefits such as reduced congestion, improved air quality, expansion of green spaces and improved physical and mental health.
As the CCC’s analysis shows, even net zero scenarios include some remaining household emissions, e.g. in diet and aviation. Negative emissions (removing carbon from the atmosphere) would therefore be required. But methods for achieving this have their limits, so the more we can curb emissions directly, the less we will have to rely on these. Care has to be taken when setting policy to drive a transition to net zero, to ensure the least well off are not disproportionately affected, particularly in the case of low carbon heating. Living Carbon Free: Exploring what a net-zero target means for households .
The UK Climate Change Act 2008 set a legally binding target of reducing greenhouse gas (GHG) emissions by 80% by 2050 compared to a 1990 baseline. This was seen as a proportionate UK response to a global effort to prevent temperatures rising beyond 2°C above pre-industrial levels. Since that time, improved scientific understanding of the risks of climate change means attention has shifted to a more ambitious target of limiting warming to 1.5°C. To succeed, we need to eliminate net1 GHG emissions globally by the second half of the century. The UK Government has asked the Committee on Climate Change (CCC) to advise on an appropriate target date for the UK to achieve net zero emissions, and whether this requires accelerated reductions between now and 2050.
The vast majority of households have a need for mobility to enable us to commute to work, go shopping or visit friends and family. For most of us, this involves a mixture of different modes of transport including walking, cycling, driving or public transport.
The story so far
Between 1990 and 2017, emissions from UK surface transport have increased in absolute terms. Allowing for growth in the number of households, the average per household emissions fell from 2,952 to 2,376 kg CO2e. Clearly different modes of travel have very different implications for emissions, with private cars responsible for the majority.
In 1990, in the UK we travelled a total of 588 billion kilometres by car. By 2017 that had risen to 670 billion kilometres. Improvements in vehicle fuel efficiency have prevented emissions from growing at the same rate, but internal combustion engines continue to dominate the vehicle fleet.
Actions for decarbonisation
Achieving a net zero target will require significant changes to how we move around. This will require both comprehensive decarbonisation of cars and vans and rethinking how we get around in the first place. Our mobility needs are diverse, and depend on proximity to the workplace, schools and amenities and many other factors.
The solutions available to us will also vary depending on whether we live in an urban city centre, the outskirts of a small town or in an isolated rural area. For example, people living in cities and towns make fewer and shorter car journeys.
Reducing overall distance travelled would mean less pressure for new transport infrastructure, thus reducing indirect emissions from extraction and processing of raw materials.
Reducing travel distance could be achieved through more flexible working patterns allowing people to work from home (or closer to home in ‘shared working’ spaces), supported by greater use of virtual rather than physical meetings. Those living in urban areas generally travel the shortest distances so, in principle, increased urbanisation of the UK population could support this transition (relative to an alternative future with more suburban or rural living).
Shifting to more sustainable modes of transport could be a cost-effective alternative to private car ownership, depending on location. In its simplest form, modal shift could mean more walking and cycling. People could also gain health benefits from a more active lifestyle.
For longer journeys or in adverse weather conditions, many of us would require some form of public transport. This can involve increased physical activity too, from walking or cycling to the local bus stop or train station.
Travel time has been found to be the biggest factor when it comes to deciding to use public transport. A more efficient and extensive public transport system would therefore ease the switch away from private car use. Mode switching will probably be easier for people living in cities and towns where investment in public transport is easier to justify.
Given that there are still a significant number of journeys done by car in urban areas, there is a large opportunity for mode switching to have a significant impact on transport emissions. This would provide the further benefits of reduced congestion and improved air quality
Exploring what a net-zero target means for households Those living in more rural areas have fewer public transport options than those in urban areas but could still take advantage of park and ride schemes for journeys into city centres, for example.
Using vehicles more efficiently would also help reduce emissions. This is most significant while we continue to drive fossil fuel vehicles, but even in the case of electric vehicles, more efficient use would mean less overall electricity generation required to charge them.
Increasing the average occupancy rate of cars, e.g. through carpooling to work, would reduce the number of individual vehicle journeys (and reduce congestion along the way). Car sharing schemes could offer flexibility for those who are able to travel primarily by public transport but may have the occasional need for a private vehicle.
Switching to new vehicle technologies will be essential. Electric vehicles on the market today offer an average range of around 240 kilometres11, which is more than sufficient for most car journeys. For example, in urban areas the average distance per trip is only 13 kilometres. Even for those living in more isolated rural dwellings the average trip is only 18 kilometres.
Of course, range requirements are not determined by average distances but by occasional longer journeys. This explains the high average range of electric vehicles currently on the market, which might be sufficient to support a typical weekend getaway. The average range of new electric vehicles will continue to increase as battery costs come down, ensuring more households can find a solution that suits all of their needs.
For very long trips, like the annual family holiday, rapid charging units at service stations can already provide an 80% charge in under 30 minutes. Some households will opt for vehicles with a much larger than average range, making a cross-country trip with one or two recharging stops a viable option.
As new business models emerge to facilitate an electric vehicle transition, other households might rely on a short-range vehicle for day-to-day use, while taking advantage of car hire schemes to take a long-range model for occasional longer journeys. Aside from fast charging stations, all EV owners will require an everyday charging facility. Those with off-street parking will be able to install a charging point of their own. For others who use onstreet parking, public charging points will have to be rolled out extensively across the UK if an allelectric vehicle fleet is to be realised.
In many cases, workplace charging will offer an alternative or complementary opportunity to recharge. There are certain hours when we need our vehicles out on the road, but usually they remain parked for more than enough hours to ensure a full charge every day, meaning we have some flexibility around when we choose to recharge them. Households can support load balancing here by opting for smart charging. This can ensure their vehicles avoid recharging at times of high demand, minimising the need for additional peak generation which can be costly (and carbon intensive when provided by natural gas turbines). (150 miles), value obtained from https://www.nimblefins.co.uk/average-electric-car-range and excludes Tesla Living Carbon Free:
The CCC’s Core scenario assumes the majority of the road transport fleet is electrified by 2050. This would lead to a reduction in emissions from transport for the average household from 2,376 to 371 kg CO2e between 2017-2050.
In CCC’s latest analysis, Further Ambition and Net-zero scenarios assume all cars will have to be fully electric (or hydrogen) by 2050, meaning household emissions from transport are effectively eliminated. To achieve this, all new car sales from 2035 will have to comply with this, allowing a 15- year period for any remaining fossil fuel vehicles to retire.