To begin with, many of the potential technologies are still a significant way from being ready for widespread deployment because of lack of qualified engineers, technicians and even technology.
The most significant markets around the world are simply not that interested. Green energy is expensive and the free market has consistently shown that the cheapest approach is to dig up fossil fuels and burn them.
The big question therefore is, if we haven’t got enough time to de-carbonize the global economy before the mean global temperature rise passes 20C. Is there something we can do to avoid a dangerous climate change and a 40 C to 60 C outcome? Is there something we can do to buy us some time while we go about this business of a low carbon transition, one which does not distract us from the principal objective? The answer to that may be found in geo-engineering.
Geo-engineering may provide an option:
IMechE carried out a review of promising geo-engineering approaches, and made an initial engineering assessment of the feasibility of the most practical solutions. The Institution presents the three most promising case studies and provides an engineer’s view of the steps needed to make geo-engineering a reality. This report clearly highlights the role of engineers in finding alternatives to mitigation and adaptation and thereby buying time for humanity.
For many years governments have primarily focused on climate change mitigation, or in simple terms, reducing the amount of carbon-dioxide each nation emits into the atmosphere. Indeed, the UK government recently released its low carbon transition plans, which the Institution welcomes as a positive plan of action for the next decade.
Engineers have been at work to find out if there is a possibility of an approach beyond mitigation and adaptation. However, a less explored avenue is geo-engineering. This is where technology is used to remove CO2 from the atmosphere or where the planet is cooled by reflecting solar radiation back into space. Geo-engineering is not an all encompassing solution to global warming. It is however, another potential component in our approach to climate change that could provide the world with extra time to decarbonize the global economy.
The initial assessment of a range of potential geo-engineering options is available under its- ‘cooling the planet program.’
Research is being undertaken into building machines which, like trees can remove CO2 from the atmosphere. This occurs when air passes through the device (the tree) and CO2 is then removed and buried underground in the same way as conventional carbon capture and storage (CCS). The UK would require 100,000 trees, each absorbing ten tonnes of CO2 per day) to capture the entire nation’s non-stationary and dispersed emissions.
Algae coated Buildings:
This approach uses strips of algae which are fitted outside the buildings. Algae naturally absorb CO2 through photosynthesis. The algae are then periodically harvested from building surfaces and used as bio-fuel in conjunction with a carbon based solution. The advantage of this proposal is that no additional land is required therefore it will not affect existing and future food production or other important land uses.
Reducing the amount of solar radiation absorbed by the earth’s climate system has the potential to cool the planet. This can simply be achieved by making surfaces more reflective and thus lowering the heating effect the sun’s rays have on us. This option may not be as effective as the other two, though it does have the additional benefit of reducing temperatures in city centres. City centres can often be several degrees hotter than the surrounding environment.
The relative use of these technologies needs to be assessed. It is also important that these potential options are not seen as alternative to climate change mitigation.
Funding for geo-engineering research is granted by the government. Any such research must be linked with existing mitigation and adaptation research.
Action must be taken for a parallel de-carbonization and expansion of global electricity generation capacity including deployment of smart super-grids on a continental scale and parallel research and development of electric transportation technologies and technologies for de-carbonization of dispersed sources.
Phased electrification of transportation sector and dispersed sources of carbon dioxide emissions. Artificial trees should be used to clean up past emissions to such a level that the atmospheric carbon dioxide concentration returns to climatically accepted levels.
Role of engineers in mitigation and adaptation measures for climate change management has often gone unnoticed as all perspective studies are covered under the term ‘scientific studies’ which gives the impression that only scientists are the key players. Searching for geo-engineering solutions has been undertaken by the scientists at their level but the lead role has to go to the engineers.