Climate change is a direct result of carbon being removed from the geosphere, the solid parts of the planet, and released into the atmosphere. The majority of “clean tech” innovations of recent years have focussed on reducing greenhouse gas emissions or producing carbon neutral energy. Carbon neutral energies produce energy without taking carbon from the geosphere, for example wind and solar power, or by removing the same amount of carbon dioxide (CO2) from the atmosphere as they produce, such as with biofuels.
Even with the technological advancements occurring in this field, it is unlikely that we will entirely reduce worldwide emissions to zero. Furthermore, achieving a carbon neutral planet would not reverse the levels of greenhouse gases in the atmosphere to that of pre-industrial times.
That’s where Carbon Dioxide Removal (CDR) technologies come in. CDR relates to methods of removing CO2 from the atmosphere permanently, by returning captured CO2 to the geosphere. CDR technologies therefore result in “negative carbon emissions”. These technologies are at an early stage of development, as discussed in our previous article here.
In October 2018 the Intergovernmental Panel on Climate Change (IPCC) published the Special Report on Global Warming of 1.5°C (SR15), discussing how a global temperature rise of more than 1.5°C could be prevented. This report stated:
“All pathways that limit global warming to 1.5°C with limited or no overshoot project the use of carbon dioxide removal (CDR) on the order of 100–1000 GtCO2 over the 21st century”.
If this is the case, innovation in CDR technologies, and therefore patent applications relating to this technology, are set to rapidly increase.
Achieving Negative Carbon Emissions
The CPC classification scheme has a number of classification codes in the Y02C10 group, which relate to capture, storage, sequestration or disposal of carbon dioxide. At the time of writing TotalPatent ® found nearly 2000 families of patent applications categorized in this classification group, published throughout the past two decades.
Many of these families will relate to emission reduction technologies such as capturing CO2 in the exhaust gasses of power generation plants. The captured CO2 is then sold to industry, with one of the most familiar examples being the production of carbonated drinks. Ultimately, the captured CO2 will still end up in the atmosphere.
To achieve negative carbon emissions two steps are needed. The first is a method of capturing CO2 which is already in the atmosphere. Capturing carbon emissions when burning fossil fuels cannot result in negative emissions, as carbon is removed from the geosphere when these fossil fuels are mined. Secondly, a way of returning the captured carbon back to the geosphere is needed, referred to as carbon sequestration.
Direct Air Capture
Direct Air Capture (DAC) is one example of the first requirement above. In DAC, CO2 already in the atmosphere is removed from the ambient air. The process general involves sucking large volumes of atmospheric air through a chemical filtering process. This CO2 must then be stored underground through sequestration methods, typically in a solid or liquid form, in order to achieve negative emissions.
Both DAC and carbon sequestration are young technologies, facing substantial hurdles in order to operate on a large enough scale to compete with the nearly 40 billion tonnes of CO2 emitted annually. Only 34 of the families in Y02C10 make a direct reference to Direct Air Capture. On the other hand, there are 732 patent families classified under Y02C10/14, subterranean or submarine CO2 storage, suggesting that development is perhaps further ahead in this sector.
A number of companies developing DAC systems, such as Climeworks and Carbon Engineering, have made headlines recently, securing large investments towards their work. The patent portfolios of both of these companies no doubt contributed to attracting investment.
However, it seems there is a long way to go for DAC to become a viable option on an industrial scale. The main problem is the current high cost per tonne of CO2 captured, roughly $100 at best. This cost issue is further compounded when carbon negative emissions are desired, as the CO2 must be sequestrated rather than resold, essentially burying the product produced rather than selling it. Government policy introducing financial incentives may well have to come into play to help support this technology.
Economic issues aside, there is at least proof of concept of this technology. Climeworks conducted a successful test in 2017 where CO2 was captured through DAC using residual heat energy from a power plant. This CO2 was then injected into the Icelandic bedrock, where it reacted to form solid mineral deposits. An estimated 50 tonnes of CO2 could be removed from the atmosphere annually using the system. However, many plants of this kind would be need to have a significant impact.
Bio-Energy With Carbon Capture & Storage
Another way to achieve negative emissions is Bio-Energy With Carbon Capture & Storage (BECCS). This method involves first producing biofuels, with plants capturing CO2 naturally through photosynthesis. Then these fuels are burnt and some of the emitted CO2 is captured and then sequestered. Unlike conventional biofuel use, the sequestering of the emissions results in overall negative carbon emissions.
BECCS technology is further ahead than DAC, with BECCS being the only CDR technology operating on an industrial scale at present. The five facilities around the world currently incorporating BECCS technology are capable of capturing a combined 1.5 million tonnes of CO2 per year.
Indeed, the Grantham Institute for Climate Change Briefing Paper No 8 stated that of the negative emission technologies studied:
“BECCS has the greatest technology maturity and could be introduced relatively easily in today’s energy system. The presence of a main saleable product (e.g. electricity from a biomass fired power plant) also contributes to making this an attractive option for removing CO2 from the air.”
However, it is clear that there is still a large amount of development required before negative emission technologies become a major player in the fight against climate change. At Reddie & Grose, we aim to help innovative companies obtain protection for their intellectual property, to help the continued development of technologies such as these.
This article is for general information only. Its content is not a statement of the law on any subject and does not constitute advice. Please contact Reddie & Grose LLP for advice before taking any action in reliance on it.