This is part 5 of our blog post series on community emissions. The first four articles investigated the development of a community GHG inventory. This article analyses community targets for greenhouse gas emissions.
What is greenhouse gas emissions community target?
A target for a city or community relates to a desired future GHG emissions result for a local government administration boundary.
Humans and communities are at the centre of climate change. Reducing emissions is a shared responsibility of governments, businesses and of cities and communities. Moreover, in the absence of strong national leadership, local governments need to step in and act. Setting targets enables efforts to be directed towards achieving that target, rather than letting emissions grow unchecked.
However, setting an appropriate target can be confusing. What percentage reduction should you choose? What target year shall you select? Should the target revolve around renewables or carbon emissions, or should you instead focus on tangible measures like solar PV installations in your community?
What targets are in line with science? What target will get accepted by the community? What kind of targets are other cities and communities setting themselves? Should the local government drive the target setting or shall efforts be community-driven?
Before we try to answer these questions, let’s have a look at the underlying problem first.
Rising carbon emissions and the Paris Agreement
Due to all historical and current carbon emissions, global temperatures have already increased by ~1°C from pre-industrial levels, with even higher increases being experienced on land. Atmospheric levels of carbon dioxide have risen to above 400 ppm, which exceeds the ‘safe’ level of 350 ppm. Moreover, the IPCC predicts that without additional efforts, there will be further growth in emissions due to increased economic activity and population growth.
The main driver of long-term warming is the total cumulative emissions of greenhouse gases over time. As shown by Climate Action Tracker in Figure 1, without additional efforts, human-caused carbon emissions may increase to over 100 billion tonnes annually by 2100, which is double current global emissions. The resulting increase in global temperatures could be up to 4.8°C (as per the IPCC Climate Change 2014 Synthesis Report).
However, with current climate policies around the world, global temperatures are projected to rise by about 3.2°C.
To prevent dangerous climate change by limiting global warming, close to 200 of the world’s governments signed the landmark Paris Agreement. The Paris Agreement forms the basis of science-based targets to limit global temperature increase to well below 2°C by 2050. With current pledges, and if all countries achieved their Paris Agreement targets, it could limit warming to 2.9°C.
However, to limit warming to well below 2°C, let alone 1.5°C, current Paris pledges made by countries are not enough. Carbon emissions need to decline at a much steeper rate in the near future and reach net-zero by mid-century to have a 50% chance of keeping warming below 1.5°C.
Achieving net-zero by 2038 improves this chance to two thirds, but global emissions would have to fall by up to 70% relative to 2017 levels by 2030. For every year of failed action, the window to net-zero is reduced by two years.
So how many greenhouse gases can still be emitted? This concept is encapsulated in the term ‘carbon budget’.
What is a carbon budget?
Just like a financial budget sets a ceiling on how much money can be spent, a carbon budget is a finite amount of carbon that can be emitted into the atmosphere before warming will exceed certain temperature thresholds.
The concept of a carbon budget emerged as a scientific concept from the IPCC’s 2014 Synthesis Report on Climate Change and relates to the cumulative amount of carbon emissions permitted over a period. Given that the carbon budget is not annual, but cumulative, it means that once it is spent, carbon emissions have to be held at net zero to avoid exceeding temperature targets.
Higher emissions in earlier years mean that there can only be lower emissions later on. You can compare this concept to your own budget. If your yearly budget was $120,000, and you spent $30,000 in each of January and February, you would only have $60,000 left to spend between March and December, or $6,000 per month. Conversely, if you are careful with what you buy and only spend $5,000 every month, then your budget will last twice as long (2 years).
The carbon budget for limiting warming to 1.5°C is smaller than the carbon budget for limiting warming to 2°C.
Please have a look at the following two carbon budgets we developed for a local government client. The ‘blue budget’ shows a 2°C pathway, whereas the ‘orange budget’ shows a 1.5°C scenario.
Example of 2°C carbon budget
Example of 1.5°C carbon budget
The area of the carbon budget is much smaller in the ‘orange’ graphic. And while both carbon budgets trend towards net zero in 2050, there are much steeper reductions earlier on in the 1.5°C scenario.
How can you set a target/carbon budget based on science?
Targets are considered science-based if they are in line with the level of decarbonisation required to keep global average temperature increase well below 2°C compared to pre-industrial temperatures, as described in the Fifth Assessment Report of the IPCC. All science-based target setting methods use an underlying carbon budget.
There is no universally accepted method of how to calculate carbon budgets at the city level and many cities have worked hard at developing a fair carbon budget. As per the C40 Deadline 2020 report, the three principles that dominate the debate on the allocation of carbon budgets are:
- Equality, based on an understanding that human beings should have equal rights
- Responsibility for contributing to climate change, linked to the ‘polluter pays’ principle
- Capacity to contribute to solving the problem (also described as capacity to pay).
Specific considerations include the current global carbon budget, adjusting it to an appropriate time frame, adjusting it from carbon dioxide to carbon dioxide equivalents, and then deriving a fair and equitable national budget. Once there is a national budget, it needs to be apportioned fairly to the city by using factors such as population and potentially adjusting it based on the sector representation in the community.
A simpler method to arrive at a carbon budget that is tracking towards net-zero is to follow a science-based target-setting method by adopting a target which is proportional to the overall world’s target using the contraction approach and to scale emissions down linearly. There are two science-based temperature scenarios you can align with, a 2°C and a 1.5°C scenario. The minimum annual linear reduction rates aligned with 1.5°C and 2°C scenarios are 4.2% and 2.5%, respectively.
Example method for calculating your science-based target
The following method, which you can use as an example, shows six steps on how to set a community emissions target based on science.
Step 1: Calculate your GHG inventory
Your carbon inventory should be aligned to GPC. Please read our article on calculating community carbon footprints if you are unsure about this step.
Step 2: Project emissions
Once you have a fully developed carbon inventory, project your emissions into the future to get an idea of where your emissions will be in the absence of any abatement measures
Step 3: Decide on carbon budget allocation method
Choose an approach that is suitable for your circumstances. The simplest method is to contract to net-zero by 2050.
Step 4: Choose a pathway
You need to choose whether you want your emissions trajectory to align with a 1.5°C or a 2°C scenario.
Step 5: Choose a target year
While you are aiming to track towards net zero by mid-century, it will help to establish interim targets, based on your chosen degree scenario.
Step 6: Validate your decisions
Consult your community to get feedback.
What kind of targets are there?
There are two main categories of targets, top-down and bottom-up ones.
With top-down goals, you set the goal first, and then determine actions to get there. Top-down targets can be informed by science (‘science-based targets’) or by a community’s aspirations. Each of these approaches effectively gives the community a carbon budget to stay within for any chosen pathway.
Externally set top-down target – science-based:
An external top-down target is informed by science. Science-based targets are aligned with either a 2°C or 1.5°C pathway and lead to net-zero emissions by 2050.
Internally set top-down target – aspirational:
Aspirational targets express the vision of a community and where it would like to be in future. They often relate to a target year earlier than 2050.
With bottom-up targets, you analyse the carbon footprint first and then develop abatement actions. Carbon reduction actions are modelled to investigate the amount of carbon reduction that can be achieved and the cost to facilitate and fund them. Based on the level of carbon reduction that is feasible, you set a corresponding target.
Top-down and bottom-up targets can work in tandem. For instance, you can decide to set a science-based target, and then translate this target into tangible, staged and evidence-based bottom-up targets. Examples of such tangible targets are the number of solar PV installations on houses, or the rate and amount of electric vehicle take-up in a community.
Who sets a community target?
Targets can come directly from the community, or they can be driven by the local government authority. If they are driven by the local government, it is a good idea to undertake community consultation, present the facts and then get feedback on the proposed target(s).
What does a net-zero target mean?
A net-zero target means that by (and from) the target date, there must be no greenhouse gas emissions on a net basis. Within the geographic boundaries of a city, a ‘net zero city’ is defined as:
- Net-zero GHG emissions from stationary energy consumption such as natural gas use (scope 1)
- Net-zero GHG emissions from transport activities (scope 1)
- Net-zero GHG emissions from electricity consumption (scope 2)
- Net-zero GHG emissions from the treatment of waste generated within the city boundary (scopes 1 and 3)
- Where a city accounts for additional sectoral emissions in their GHG accounting boundary (e.g. IPPU, AFOLU), net-zero greenhouse gas emissions from all additional sectors in the GHG accounting boundary
Table 1: Definition of a net-zero target for a city
Once you have achieved carbon neutrality, it needs to be maintained year after year. For further information, please refer to the C40 paper, ‘Defining Carbon Neutrality For Cities And Managing Residual Emissions’.
Using carbon offsets to reach net-zero
Even after you have reduced your emissions as much as possible, there may be a residual carbon footprint. It may not be technically or economically possible to achieve zero emissions for all inventory sources, in which case you can consider carbon offsets.
As per the C40 paper Defining Carbon Neutrality for Cities, possible approaches for carbon offsets you can consider include:
- Developing carbon offset projects outside of the city GHG accounting boundary (including local/regional projects that may or may not generate tradeable carbon credits) and taking responsibility for managing the project for the duration of its lifetime;
- Investing in carbon offset projects outside of the city GHG accounting boundary (e.g. provide funding to enable a project to get underway or commit to purchasing a set quantity of future vintages, thereby providing upfront funding for credit registration costs), and
- Purchasing carbon offsets from outside of the city GHG accounting boundary (local, national, or globally-sourced projects that generate tradeable carbon credits) from a registered/credible/established carbon credit provider.
As with any carbon offset purchase, your carbon credits should be credible and of high quality. Criteria that your carbon offset projects should achieve are that they are real, additional, permanent, measurable, independently audited and verified, unambiguously owned and transparent.
Using Carbon Dioxide Removal and Negative Emissions Technology to reach net-zero
Carbon Dioxide Removal (CDR) means that you are removing carbon dioxide from the atmosphere in addition to what would happen anyway via the natural carbon cycle. Because you are removing carbon emissions, this is also called ‘negative emissions’, or ‘negative emissions technology’ (NET).
You can draw out excess carbon dioxide from the atmosphere by enhancing natural carbon sinks (trees and soil) or using chemical processes, such as extracting carbon dioxide from the air and storing it somewhere suitable (e.g., underground).
Negative Emission Technology (NET) is at various stages of commercial development and differs in terms of maturity, scalability, costs, risks, and trade-offs. To date, none of these technologies has been adopted at large scale.
As a side note, in IPCC modelling, all pathways that limit global warming to 1.5°C include CDR measures. If we cannot reduce emissions fast enough, global temperatures will overshoot 1.5°C, which means that we need NET to bring global temperatures back down.
A city that plans on utilising NET is Oslo. The single biggest carbon reduction measure in Oslo’s Climate and Energy Strategy is the implementation of carbon capture and storage (CCS) at its Klemetsrud waste incineration facility.
Target setting under the Global Covenant of Mayors and C40
Target setting under the Global Covenant
The Global Covenant of Mayors for Climate & Energy (GCoM) is the world’s largest alliance of cities and local governments with a shared long-term vision of promoting and supporting voluntary action to combat climate change and move to a low emission, climate-resilient future. As of October 2019, 26 local governments in Australia have joined the GCoM.
Through the GCoM, cities and local governments are voluntarily committing to fight climate change, mirroring the commitments their national governments have set to ensure the goals of the Paris Agreement are met.
Local governments committed to GCoM pledge to implement policies and undertake measures to:
- Reduce/limit greenhouse gas emissions
- Prepare for the impacts of climate change
- Increase access to sustainable energy
- Track progress toward these objectives
When you join the Global Covenant of Mayors, you need to submit a greenhouse gas emissions reduction target(s) within two years upon joining. The target boundary needs to be consistent with all emissions sources included in your GHG emissions inventory. The target year needs to be the same (or later than) the target year adopted nationally under the Paris Agreement. The national target is called the ‘Nationally Determined Contribution’ (NDC).
If you set a target beyond 2030, you also need to set an interim target. The target needs to be at least as ambitious as the unconditional components of the NDC. You are only allowed to use carbon offsets if your target’s ambition exceeds the NDC.
Target setting under C40
C40 is a network of the world’s megacities committed to addressing climate change. Cities that commit to being part of C40 need to have a plan to deliver their contribution towards the goal of constraining global temperature rise to no more than 1.5°C. In Australia, Sydney and Melbourne are members.
To remain within a 1.5°C temperature rise, average per capita emissions across C40 cities need to drop from over 5 t CO2-e per capita to around 2.9 t CO2-e per capita by 2030. Every city needs to diverge considerably from its current business-as-usual pathway and cities with a GDP over USD15,000 per capita must begin to reduce their per capita emissions immediately, which results in an immediate and steep decline of emissions.
C40 recommends that the trajectory for emission reduction follows the typology as introduced in Deadline 2020.
- Steep Decline – Cities with a GDP per capita over $15,000 and emissions above the average for C40. Emissions need to be immediately and rapidly reduced and the city is sufficiently developed to do so.
- Steady Decline – Cities with a GDP per capita over $15,000 but emissions lower than the average for C40. The city is sufficiently developed to immediately reduce emissions, but a less rapid rate of reduction is required than for the Steep Decline group.
- Early Peak – Cities with GDP per capita below $15,000 and higher than average emissions per capita. An early emissions peak is required, although the city’s development status means that decline cannot be immediate.
- Late Peak – Cities with a GDP per capita below $15,000 and lower than average emissions per capita. A slightly later emissions peak is possible.
The following table shows the current and reduced science-aligned and C40 per capita emissions for scopes 1, 2 and 3.
Table 2: Average per capita emissions figures for C40 cities in 1.5- and 2-degree trajectories
Examples of city targets
The following list shows examples of ambitious targets for cities across five continents.
EThekwini Municipality, Africa
The eThekwini municipality includes the city of Durban, South Africa and surrounding towns. It is the first city in Africa to develop a 1.5°C climate action plan with the support of the C40 Cities Climate Leadership Group. The target is to reach a 40% reduction in emissions by 2030 and 80% reduction by 2050.
Hong Kong, Asia
In May 2019, Hong Kong achieved CDP’s top ‘A’ score for its climate strategy, among 7% of cities reporting to the CDP. Hong Kong’s targets are as follows:
- Reduce carbon intensity by 65% to 70% by 2030 compared with the 2005 level, which is equivalent to an absolute reduction of 26% to 36%
- Resulting in per capita emission of 3.3 to 3.8 tonnes in 2030
- Carbon emissions to peak before 2020
The 2030 Climate Plan includes objectives, such as phasing down coal for electricity generation and replacing it with natural gas by 2030, saving energy in the built environment, focusing on rail as a low-carbon public transport backbone and encouraging active transport modes, such as walking.
The Australian Capital Territory (ACT), Australia
The ACT is a federal territory of Australia containing the Australian capital city of Canberra and some surrounding townships. The ACT’s first targets were introduced in 2010, revised in 2016 to increase ambition and again in 2018. The current targets are to reduce emissions (from 1990 levels) by:
- 40% by 2020
- 50-60% by 2025
- 65-75% by 2030
- 90-95% by 2040
- 100% (net zero emissions) by 2045.
The ACT also set a target to peak emissions per capita by 2013. This was achieved in 2012-13 at 10.53 tonnes of CO2-e per person and has remained below this level ever since. In 2017-18, emissions were 8.09 t CO2-e per capita. The ACT’s targets were informed by considering the ACT’s share of the global carbon budget.
Oslo has the objective to become a ‘virtually zero-emission city’. The current targets are as follows:
- Greenhouse gas emissions should not exceed 766,000 tons of CO2-e by 2020 (applicable to all emission sectors except agriculture, aviation and shipping)
- Reduction of greenhouse gas emissions by 95% by 2030 (compared to 1990 levels)
The second goal depends on the successful removal of emissions from a major waste incineration plant.
In 2016, Oslo introduced a climate budget, which sets a ceiling on the volume of carbon dioxide that can be emitted in the city in a given year. The climate budget is fully integrated with the financial budget of the city. The climate budgets show measures implemented or planned for Oslo to reach its climate targets and become a low-carbon city.
San Francisco, North America
In its Focus 2030: A Pathway to Net Zero Emissions, San Francisco defines the following targets:
- Supplying 100% renewable electricity from 2030
- 68% reduction in emissions below 1990 levels by 2030
- 90% reduction by 2050
San Francisco identified that emission reduction must come from three primary sectors, being buildings, transportation and waste. The city also defined sub-targets for these sectors.
- Shift 80% of all trips taken to walking, biking and transit by 2030.
- Electrify 25% of private cars and trucks by 2030 and 100% by 2040.
- Electrify space and water heating with high-efficiency products such as heat pumps
- Increase building energy efficiency
- Power buildings with 100% renewable electricity
- Reduce generation by 15% by 2030
- Reduce disposal to landfill or incineration by 50% by 2030
Cities and communities should consider setting themselves targets in line with science. To avoid catastrophic climate change, emissions need to start falling now and reach net zero by 2050. Interim targets will help to stay under an allocated carbon budget.
Both vision and leadership are needed to enable steep cuts to our emissions, which translates into unprecedented, rapid change across the globe to limit global warming. The way electricity is generated needs to change to clean energy. The way we transport people and goods and the way we produce everything needs innovation. Land use planning plays a big part, and different economic models need to be adopted that will makes such a transformational shift possible. In the next part of this series, we will look at community carbon abatement measures in greater detail.
100% Renewables are experts in helping organisations, communities/LGAs and councils determine suitable targets, be they science-based, aspirational or bottom-up/action-based. Our community inventories align with the GPC and targets can be based on IPCC global carbon budgets. If you need help with your community inventory, please contact Barbara or Patrick.
 For instance, Australia’s commitment under the Paris Agreement is 26-28% below 2005 levels by 2030
Feel free to use an excerpt of this blog on your own site, newsletter, blog, etc. Just send us a copy or link and include the following text at the end of the excerpt: “This content is reprinted from 100% Renewables Pty Ltd’s blog.