The urgency of addressing the climate crisis has been widely recognized by world governments, international organizations, various corporations, and the broader civil society. The Paris Climate Conference (COP21) in December 2015 was a significant milestone for global efforts to address Greenhouse Gas (GHG) emissions. In this agreement all countries agreed to keep the earth’s temperature 2 °C below what the temperature was during pre-industrial temperature levels and to pursue efforts to reduce even more to 1.5°C. However, with the current rate of GHG emissions, the Paris Climate Agreement[1] will fail to keep global warming below 2 °C by 2100. The 2016 UN Emissions Gap Report states that national mitigation pledges are still insufficient for reaching the goal of limiting global temperature rise to below 2°C above pre-industrial levels[2]. The Intergovernmental Panel on Climate Change (IPCC) has estimated that decarbonization and negative emissions would be required in order to achieve this goal.
“With the current rate of GHG emissions, the Paris Climate Agreement[3] will fail to keep global warming below 2 °C by 2100.”
The climate crisis is a complex one, and many issues certainly come into play. One key issue is the lack of political will; we are simply not trying hard enough. Another issue is that understanding the most important fundamental technical concepts relevant to the climate debate is challenging for decision makers. In this article we will touch on some of the important aspects that we believe are of absolute importance. Understanding these aspects will help enrich and inform decision making and public discussions.
Emissions Scopes
This concept identifies the boundaries of the challenge, it is like wrapping your hands around the target. Emission scopes were developed by Greenhouse Gas Protocol in 2016 for buildings However, we believe they are still useful as a general concept that can be expanded to other areas. These scopes identify the location of the emissions among other important aspects. This is very important because some technology advocates can claim that certain technologies at certain locations do not produce emissions where the energy is consumed, while in fact using these technologies will not mitigate GHG emissions. For example electric cars or hydrogen combustion technologies are being targeted as emission mitigating technologies however, using such technologies may not mitigate emissions because the emission scopes are not fully considered. Now, let’s expand on this concept of emission scopes.
Scope 1 emissions are direct emissions, if the consumer is using an electric car, heating your building entirely using electricity, or melting steel in a factory using an electric induction furnace, your Scope 1 (site emissions) are zero. Accounting for these emissions is generally good for quality of air and human health and reducing air pollution, but not necessarily enough to solve the climate crisis or reducing GHG. The reason being is that there are upstream activities that are associated with the energy supply chain that may contain emissions prior to reaching the site.
The simplest example is burning coal to produce electricity in a power plant that supplies the electricity grid and then the electricity is used to charge electric cars/busses/trains for the consumers to utilize. While there are no emissions on site, in this example GHG are still released into the atmosphere at the electricity generation site, it is just the consumer is not experiencing the emissions. A simple way to avoid this misunderstanding is ask; “where is the energy I am using originally from?”
Scope 2 emissions are indirect emissions associated with the generation and transport of the energy prior to consumption, here we start to consider where the energy originally came from. In the prior example this will consider if the electricity used in electric cars is produced from coal or natural gas, in this case, even if it sounds strange, driving an electric car may have emissions associated with it.
Scope 3 emissions are all other indirect emissions, this includes all upstream and past emissions that are associated with human activity. This may be called embodied emissions when considering buildings, and may include emissions released in resource extraction for manufacturing, or released in the manufacturing processes to produce a product consumed.
Zero Carbon vs Carbon Neutral
It is critical to understand the difference between the concept of Zero Carbon and Carbon Neutral. A true Zero Carbon activity would involve no direct or indirect emissions. This is straightforward for direct emissions; no burning of fossil fuels at a certain location, for indirect emissions it becomes more complex because achieving zero carbon, in this case, will involve ensuring that suppliers of energy (electricity) or zero carbon fuels (uranium, hydrogen) don’t emit carbon at the point of production (see emissions scopes above). Another complexity arises for zero carbon is quantifying indirect emissions emissions in manufacturing or goods and materials. A true zero carbon world will have no direct or indirect emissions, this is the ideal best case scenario for mitigating climate change.
On the other hand, Carbon neutral means emitting carbon and its equivalent GHG and somehow offsetting the effect of these emissions. The easiest way to do this is to plant areas that did not previously contain vegetation, where the amount of carbon dioxide absorbed by these new plants offset the amount of carbon emitted in the first place. While this concept sounds simple, it’s hard to achieve, measure, and verify. Another not very easy way to achieve carbon neutrality is through carbon capture, which happens after emissions take place, and this involves redirecting the emitted GHG to prevent carbon from getting into the atmosphere. While this idea works in theory, it is still not fully clear if this idea can scale up to a global level and provide economic benefits. Another concept for carbon neutrality is using renewable fuels like biofuels, renewable natural gas, biomass, these fuels still emit carbon but it is claimed that over their lifetime the processes involved in producing them absorb enough GHG to offset these emissions.
The most important questions to ask are: for zero carbon, how about indirect emissions? And for carbon neutral, how is it achieved and measured?
Emission scopes and Zero/Neutral Carbon concepts are great concepts for anyone to understand to have an informed discussion with others. In the next article we will expand to other important concepts that pertain to renewable energy.
If you learned something new or liked this content follow me here
For questions, showing support, and feedback contact me here
[1] “The Paris Agreement | UNFCCC.” https://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement. Accessed 26 Dec. 2020.
[2] “Emissions Gap Report 2020 | UNEP – UN Environment ….” 9 Dec. 2020, https://www.unenvironment.org/emissions-gap-report-2020. Accessed 26 Dec. 2020.
[3] “The Paris Agreement | UNFCCC.” https://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement. Accessed 26 Dec. 2020.
