The scourge of metropolitan air pollution
- Will Hazlerigg
- Jan 31, 2018
- 3 min read
How can we improve air quality in a metropolis like London? This is a question that is very à la mode at the moment, especially as London breached it’s annual limit yesterday. Air pollution is the presence of gases and substances in the air we all breathe that are harmful and detrimental to our well-being. These pollutants have adverse impacts on health, estimated at around 40,000 deaths a year in the U.K. Urgent steps need to be taken to reduce them for the greater good of everyone that live in cities, not just in England but world-wide.
The main pollutants of concern in London are nitrogen oxides which are noxious gases (mainly nitrogen dioxide aka NO2), and particulate matters (PM), which are very small particles made up of a variety of harmful substances. There are other pollutants which are also harmful, such as carbon monoxide, sulphur dioxide and benzene, although levels of these gases are much lower in London.
So what can be done by you at home you might ask. There are simple things like driving your car less, taking public transport or riding a bike and turning off your car’s engine if you are stationary for more than a minute. These little things should be very easy to work into your everyday life style.
However there are much harder obstacles to overcome, for example heating. Gas combustion is the second largest source of NO2 emissions after road transport. So one way to make this less of a problem is to install renewable energy sources for your home. When comparing prices between installing renewable power versus a gas boiler on the mains gas grid the costs are very high, so not really an easy thing to promote in London. The cost of a gas boiler is much lower than that of an air source heat pump, as the gas boilers are so simple in the way they operate. What is easier is to promote the install of super efficient gas boilers, ones that burn the gas more effectively and pollute far less. This could be done at policy level, by not allowing boilers that are inefficient to be sold or by putting a minimum permitted energy performance threshold in place.
An alternative solution would be to promote people to switch out old inefficient boilers by creating a boiler cashback scheme, which would drive down the costs of replacing older models. And another way to lessen the impact of your home heating is to make the one you have work more efficiently: by installing a smart device such as the Nest Thermostat, which controls the way you heat your home more efficiently by only heating when you need it to. Nest claim that it can make you between 8.4% and 17% more efficient in the way you heat your home, and in our experience as a Professional Nest installer this is very much the case.
Modelling suggests that a well-considered combination of new policies will deliver compliance with NO2 limits across 99.9% of London’s area by 2025 – representing a massive improvement in air quality compared to the current situation. Policy Exchange has suggested further targeted actions to achieve compliance on the remaining roads in London, in particular targeting further reductions in bus and freight related emissions. More needs to be done and there is no time like the present!
Great articles to delve deeper and an app called London Air that shows Live pollution levels:
