The air we breathe is vital for life. However, since the dawn of industrialisation our air has been slowly polluted.
With the innovators of the 1800’s unaware of the devastating legacy they were leaving to future generations, fossil fuels, mostly coal & oil were the fuels which forged our way into an industrial age.
Long term exposure to air pollution has been proven to contribute to between 28,000 – 36,000 deaths a year in the UK (2) & a vast 4.2 million deaths globally (1) There is strong evidence that air pollution causes the development of coronary heart disease, stroke, respiratory disease and lung cancer, & exacerbates asthma. (2)
There are three main forms of air pollution identified by BreatheLife, a joint campaign led by the World Health Organization (WHO) & the Climate & Clean Air Coalition (CCAC)
Black Carbon – Produced most often by diesel engines, burning trash, and cooking or heating stoves that burn coal, kerosene or biomass (organic matter such as wood or animal waste).
Black carbon particles are fine enough to penetrate deep into the lungs, bloodstream, heart and brain, causing inflammatory responses and other long-term health effects.
Ground-level ozone – Forms when emissions of methane, nitrogen oxides and other “precursor” pollutants from industry, traffic, waste and energy production interact in the presence of sunlight.
A major factor in respiratory illness and has been shown to decrease crop yields, spurring food security challenges and poor nutrition.
Methane – 40% of human-generated methane emissions come from agriculture, primarily rice paddies and livestock production. This is followed by emissions from sewage and solid waste, and oil and gas production.
Methane emissions contribute significantly to the development of ground level ozone; chronic exposure to ozone is a factor in asthma and other chronic respiratory illnesses, and can harm childhood lung development. (3)
The data & the facts speak for themselves, but there are ways in which our air quality can be improved & help reduce the pollutants in the air we breathe.
This can be done using a combination of technological innovation & an increasing interest in green spaces & ‘rewilding’
Dolphin N2 – Recuperated Split cycle engine for Heavy Duty Trucks & Off Highway
The Recuperated Split Cycle engine has the potential to reduce fossil fuel use by up to 30% whilst simultaneously reducing air pollutants to well below any future planned legislation.
CryoPower and ThermoPower are Recuperated Split Cycle Engines. The revolutionary step is to separate the “cold” and “hot” parts of the traditional internal combustion engine.
A first set of cylinders draw in air and compress it – in the CryoPower version, Liquid Nitrogen is injected to keep this process cool for maximum efficiency; the simpler ThermoPower injects water.
The compressed air passes through a recuperator, where the engine’s exhaust heats it up – saving fuel which normally has to do this. The air now passes to the second, hot cylinder set, which are thoroughly insulated – infeasible in a normal ICE where the same cylinder handles hot and cold processes.
These cylinders host the combustion and expansion events, which produce power; they are bigger than the compressor cylinders (again impossible in a standard engine) because that is most efficient.
The very low level of emissions, especially NOx and Particulates, can be reduced to at least SULEV and potentially lower using known “SCR” (Urea-based) after-treatment. (4)
One of the strategies cities are using to improve air quality is to remove as many vehicles as they can from inner city roads & use natural greening processes to help purify the air.
City of London living walls & vertical vegetation
In 2008 the pioneering Living Roofs & Walls Policy was introduced into the London Plan & over the past decade green roofs (living roofs) & green walls (living walls) have become a more obvious choice for urban greening in London.
Since then, green roof & wall uptake in both large and small developments has increased annually across London. Inner London boroughs & in a few of the outer London boroughs where there is major regeneration, have seen the main uptake as the strategy rolls out.
As a result:
- The total area of green roofs in the Greater London Area was 1.5 million m2, which equates to 0.17m2 of green roof per inhabitant (2017 figures)
- In the Central Activity Zone (CAZ) green roofs covered 290,000m2 , which equates to 1.26m2 of green roof per inhabitant (2017 figures). This is higher than many other cities in the world which are famed for their green roofs
- 42% of the total UK green roof market is in London (2016 figures) (5)
One area of innovation which is generating a new dynamic in air purification, is where science/technology & natural processes merge. The BioSolar Leaf technology joins a wealth of innovators cultivating natural ways to green roofs & vertical spaces & in doing so, help reduce pollutants in the air.
Arborea ‘BioSolar Leaf’
A new start up, Arborea, in collaboration with Imperial College London, are spearheading their ‘BioSolar Leaf’ technology to improve air quality.
The technology, which is the first of its kind in the world, purifies the air through the photosynthesis of microscopic plants, removing greenhouse gases from the environment whilst generating breathable oxygen.
Arborea have developed an innovative cultivation system which facilitates the growth of tiny plant-life – such as microalgae, diatoms and phytoplankton – on large solar panel-like structures. These can then be installed on land, buildings and other developments to improve surrounding air quality.
The team say that Arborea’s cultivation system can remove carbon dioxide and produce breathable oxygen at a rate equivalent to a hundred trees from the surface area of just a single tree. (6)
Written & cited by Katy-Jane Mason for & on behalf of Dolphin N2
- https://www.who.int/health-topics/air-pollution#tab=tab_1
- https://www.gov.uk/government/news/public-health-england-publishes-air-pollution-evidence-review
- https://breathelife2030.org/the-issue/health-and-climate-impacts/
- https://dolphin-n2.com/technology/
- https://www.london.gov.uk/sites/default/files/2019_london_living_roofs_walls_report.pdf
- https://www.imperial.ac.uk/news/191026/worlds-first-biosolar-leaf-tackle-pollution/
