On the 29th 2018 November, I attended a conference “Accelerating CCUS” held in Edinburgh at the Hub, an impressive former Victorian church. The message of deliverance from the evils of global warming was received with enthusiasm by the congregation of the faithful, but it remains to be seen whether the message will lead to the conversion of non-believers. Following is the briefest of summaries of the day’s discussions.
· On October 8th 2018, the Intergovernmental Panel on Climate Change (IPCC) released a report requested at the Paris Agreement, “The Special Report on Global Warming of 1.5 °C”. The report concludes that to avoid the worst impacts of global warming the mean temperature rise should be limited to 1.5°C not the 2°C agreed in Paris. At the current rate of GHG emissions, on average, the 1.5°C limit will be reached by 2040 and the 2°C limit by 2052. These limits could be reached earlier depending on the interaction of various feedback loops. Current global CO2 emissions are 40 billion tonnes per year and need to become net zero by around 2050. In addition, releases to atmosphere of methane, nitrous oxide, and carbon black need to be reduced markedly. All to be done in less than 30 years, the time required to count to just 1 billion. No latitude for delay, need to act now.
· For reference, the UK’s CO2 emissions are 0.37 billion tonnes per year (less than 1 percent of global total) and 90 percent come from oil and gas utilization. Eliminating the use of these fossil fuels in the short-term is not feasible, but using them to produce hydrogen and storing the CO2 is feasible.
· There is no single technological solution to reduce CO2 emissions: efficiency improvements, eliminating coal for power generation, widespread deployment of renewables, reforming methane to hydrogen, CCS, CCUS, and nuclear are all required.
· Governments will determine what solutions best fit their economic circumstances in meeting their Paris Agreement obligations. A concern is that of stranded assets; for example, many coal-fired power plants are less than 10-years old and have been costed for 25-year life spans. Similar considerations apply to other industries such as transitioning shipping from diesel to hydrogen.
· Without CCS and CCUS achieving global climate goals will be practically impossible. Because of this, the IEA has made these technologies a priority to be discussed at all Ministerial meetings.
· To achieve this Ulyssean task, negative emission technologies (NETs) will have to be deployed. Further, once achieved the atmospheric CO2 burden will maintain the global temperature at the elevated level so NETs will remain in service for many tears. The most promising is bio-energy with carbon capture and storage (BECCS) whereby biomass is burned for power generation and the resulting CO2 stored below ground. An issue with this vital approach is land usage with biomass for energy competing for space with crops for food. With respect to food growing efficiency, as meat production requires a lot more space than growing vegetables, eating beans in preference to meat will help free space for biomass energy crops.
· If the populace is serious about saving the planet then some hard choices need to be made to lower personal CO2 footprints: travel less (air, sea, and auto), modify your diet, use energy and water more efficiently, etc.
Perhaps most importantly make saving the planet a ballot box issue so politicians have to take notice if they want to get elected and remain in office. Force them to make the difficult choices to lower GHG emissions with the budget available. Spend less on space research and seeking out other planets until ours is secure and safe.
CCS is carbon capture and storage and CCUS is carbon capture, utilization, and storage (CO2 used for different products such as aggregates and various chemicals)
If either CCS or CCUS was that straightforward and financially viable, it would be far more widely used than it is. I understand that many attempts to build full scale plants have not worked at all well and some have been abandoned. So while it would seem a great idea, scaling is a major issue. You can very effectively capture CO2 with light metal hydroxides, for example. But you can't scale it to practically useful size!
While this is a discussion on CCS, Dr Gungor mentions the nuclear industry. In my view that industry should examine ways of recovering more of the latent energy in its primary fuel, not 'burning' about 5% and burying the rest in the ground. At least burning coal extracts all the available chemical energy - the losses are due only to thermodynamic issues.
There are several large-scale CCS projects in service, so the technology is proven and technically viable although current economics discourage its widespread deployment unless additional revenue is raised by using the CO2 for enhanced oil recovery. Some may have been abandoned but a lot more have progressed, entered service, and operated successfully. As nations get more serious about reducing CO2 emissions and a price is ascribed to CO2 (circa $30/tonne), CCS will be deployed more widely because frankly, fossil fuel usage is not going to disappear any time soon.
To illustrate the type of capture projects, some large-scale examples are presented. There are other similar projects either in service or proposed to enter service in the next five years. Currently, 40-M tonnes of CO2 are being captured per year and to date over 200-M tonnes have been sequestered.
· The Sleipner gas development project uses an amine-based capture process (Aker Solutions) to remove CO2 from natural gas (with light oil condensates) prior to its liquefaction. The separation plant is located on a platform in the North Sea. Operations started in 1996 capturing up to 0.9-M tonnes of CO2 per year injected in off-shore geological strata. To date, over 17 million tonnes of CO2 have been injected for permanent storage.
· The Coffeyville plant uses a Selexol process to remove CO2 from syngas produced by gasifying petroleum coke. Up to 1-M tonnes of CO2 per year are removed (since 2000) mostly for fertilizer production (CCUS) with the rest for enhanced oil recovery (since 2013). To date, around 6 million tonnes of CO2 have been capture for fertilizer production and around 3 million tonnes injected for permanent storage.
· The Abu Dhabi project uses an amine-based capture process (MEA) to remove CO2 from methane steam reformer gases ahead of a steel manufacturing process. Operations started in November 2016 capturing up to 0.8 M tonnes of CO2 per years for enhanced oil recovery.
· The Petra Nova project uses an amine-based capture process (MHI) to remove CO2 from coal-fired power plant flue gas. Operations started at beginning of 2017 capturing up to 1.4-M tonnes of CO2 per year for enhanced oil recovery.
· The Gorgon gas development project uses an amine-based capture process (MDEA) to remove CO2 from natural gas prior to its liquefaction. Operations started mid-2018 capturing up to 4.0-M tonnes of CO2 per year injected in off-shore geological strata.
CO2 utilization technologies are in the early stages of development. One of the most promising is in the production of building materials such as aggregate, concrete, and wallboard. Such technologies permanently remove CO2 from the atmosphere. Other CO2 utilization technologies produce liquid fuels for transportation, and although the CO2 is re-released upon usage this approach lowers the dependence on fossil fuels. It is estimated that utilization technologies could lower annual global CO2 emissions by 5 billion tonnes. 12.5 percent of the current total of 40 billion tonnes. A significant contribution but still leaves a lot of work to do.
The current approach to lowering CO2 emissions is to eliminate coal and add wind, solar, and nuclear for power generation. The intermittent nature of renewables requires some form of reliable backup power and as nuclear cannot follow load the backup power has to have operational flexibility. The backup power will come from fossil fuels with CCS. The proportion of power from the four sources within an integrated generation system will be that which produces power at minimum cost.
In 2016 fossil energy consumption was 132,000 TWh of which 13 percent (16,500 TWh) was used to generate power, the remaining 115,500 TWh were used for heating (commercial, domestic, and industrial) and transportation (air and land). How to reduce CO2 from this much large emission source into which few inroads have been made? Some suggest going all electric, others all hydrogen; the truth will lie somewhere between. Hydrogen will be produced primarily by steam reforming natural gas with the CO2 by-product being stored below ground. For either approach, the undertaking is gargantuan. Currently nuclear and renewables produce around 2630 and 1560 TWh of power, respectively (hydro produces 4070 TWh with limited potential to increase further) so prorating, nuclear capacity would have to increase by a factor of around 30 and renewables, to cater for their intermittent nature, would have to increase by a factor of 90. Similarly, for CCS, currently 40 million tonnes of CO2 are stored per year and this would have to be increased by a factor of 1000 to store the 40 billion tonnes currently released. Moreover, these large increases in designing, manufacturing, and installing a new line of equipment (constituting new sources of CO2 emissions) all have to be achieved in 20 years.
Given what needs to be achieved and the importance of succeeding, all approaches need to be set in motion. Energy efficiency improvements, reforestation, reducing usage of all fossil fuels (not just coal), widespread deployment of renewables, reforming methane to hydrogen, CCS, CCUS, and nuclear are all required. Regrettably, I believe the target will still be missed, so best invest in air conditioning or seriously start considering solar radiation management to extend the time available to achieve net zero CO2 emissions.
The link between CCS and nuclear sounds like fake news to me. Where is the smocking gun?
Entirely valid concerns that have been investigated extensively over the last few years: little is gained if the CO2 leaks back to the surface. Storing in deplete gas and oil reserves would seem to offer little risk as the fossil fuel was stored there safely for millenia. Below is a link to a recent report and a search will find others.
https://www.carbonbrief.org/world-can-safely-store-billions-tonnes-co2-underground
Norway and the UK have been extracting natural gas from the North Sea and are confident that a combination of deplete gas and oil fields, and saline and sandstone deposits offer vast storage potential. Norway is proposing an infrastructure that would allow storage via pipelines and tankers drawn from across Europe. I would imagine that the Gulf of Mexico offers similar potential. Various investigations have tested underwater monitoring systems to identify and locate leakage points. On shore storage might be restricted by resident’s concerns over the damaging effects of leakage and tremors. Nevertheless, it is widely accepted that there is sufficient CO2 storage available for many years until the world is able to wean itself off fossil fuels or at least greatly reduce its dependence on them.
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