London's air pollution crisis is a wicked problem, by nature hard to define and lacking a single or best solution. It is a sociotechnical issue, relating not just to technology but to the social structure in which it is embedded.

Innovation is urgently needed to improve London's air quality and one way to accelerate this is through challenge prizes. We're gathering people in the know on 15 March to identify key innovation challenges, and which of these a prize might help overcome. There are multiple areas in which innovation can help London breathe easy, and a few of these are outlined below.

Engine innovation

Road transport is the primary contributor to air pollution in London, in particular diesel engines, and innovation in engine design and aftertreatment systems can reduce emissions to zero or near zero. However, ultimately the use of diesel is unsustainable and alternative fuel sources are need, such as electric batteries, hydrogen fuel cells, liquefied petroleum gas (LPG), or more blue skies solutions such as a cryogenic engine that runs on liquefied air.

A lot of clean technology is already out there and some may argue a greater problem is uptake, hindered by cost and infrastructural issues, so a challenge prize could tackle a particular technology bottleneck, but uptake and roll out of clean technology must be a core consideration.

In the shorter term there is a need to retrofit the existing vehicle fleet with improved aftertreatment systems or to make them compatible with cleaner fuels. So far, due to the cost and bulk of retrofitted aftertreatment systems and engine conversions, this has only been practical for commercial vehicles such as HGVs and buses that are expensive to replace and that can generate income to recoup the retrofit investment.

For passenger vehicles retrofitted aftertreatment systems are not currently viable as they will incur upfront costs comparable with purchasing a new vehicle, can add weight, reduce performance and may reduce the car's value. It may be possible to miniaturise and reduce costs of passenger vehicle diesel retrofit solutions, though the economics of this may remain problematic.

Getting cars off the road

If existing cars can’t be made cleaner they will have to be taken off the roads. Many people have suggested an outright ban, indeed Paris, Mexico City, Madrid and Athens have recently announced bans. It is understandable, however, that many people may think a ban unfair given previous government incentives promoting diesel in the very recent past due to greater CO2 efficiency at the time.

Instead of a ban, the UK has favoured market incentives, with the introduction of low emissions zones with surcharges for polluting vehicles. London will introduce the Ultra-Low Emission Zone in the centre of the city in 2020 (it has been suggested that it may be brought forward to 2019), and an Emissions Surcharge (or T-Charge) will be implemented from October this year. However, this focuses on older diesel vehicles when it has been shown that even the latest diesel are far in excess of emissions limits in real world conditions. Innovation here could focus on easier, cheaper ways of monitoring emissions of vehicles on the road, innovative diesel scrappage schemes or new ways to manage traffic or encourage car sharing, public transport or cycling and walking.

Filtering the air

One of the complexities of London’s air quality problem is that pollution varies by time and location, but there are persistent hotspots such as Oxford St, Brixton Rd and (most worryingly of all) the Victoria Embankment - location of the Nesta offices. A raft of solutions have been developed around infrastructure that will mitigate pollution at these hotspots. These could be bus shelters and benches with inbuilt pollution filters, or dedicated smog sucking towers that remove airborne particles. Some companies have developed plant-based ‘green-wall’ solutions that will make the surroundings more attractive and clean the air at the same time, while another approach is the use of new materials in the built environment - particularly catalytic concrete containing titanium dioxide that will break down NO2 to harmless products.

These solutions could be seen as a sticking plaster that doesn’t address the root cause of the problem, but when pollution is associated with premature deaths in the here and now there is a strong case for them. A challenge prize might be able to crowd in innovative ways to clean the air directly, or to encourage uptake of the existing means.

Behaviour change

Whether the solution is about adoption of clean transport technology, support for scrapping diesel or introducing air filtering infrastructure, ultimately individuals and society will need to change their behaviour to clean up London’s air. This could be through a radical rethinking of transportation, for example reconceptualising mobility as a service, or changing procurement policies to mandate that freight companies use low emissions vehicles. Innovative ideas will ultimately drive this social change.

Public engagement is key to putting pressure on policy-makers and industry for change. Companies are making use of the latest digital technology like the internet of things, open and big data, smartphone sensors, and even hi tech pigeons to raise awareness of the problem and advance our understanding of pollution and its health impact. There is huge potential for technology to interact with the social to deliver change by increasing engagement and understanding, and perhaps this is the most important challenge amenable to a prize.

Challenge Prizes

Solutions to wicked problems usually involve greater collaboration, increased competition, or recourse to a single authority. All of these approaches will be needed here for different aspects of the problem. Challenge prizes can foster innovation through the first two, increasing competition in the marketplace at the same time as fostering new collaborations, acting as a powerful incentive to prioritise key problems and crowd in solutions in excess of what a grant funding approach can acheive.

On 15th March we’ll be gathering solution providers with a range of different perspectives, along with campaigners, policy makers and academics, in order to unpick this intractable, thorny issue. This will cover many of the innovation issues identified here, and hopefully a few more.

More information about the event can be found here.

Register your interest by emailing us at [email protected]

Visit the challenge prize centre website for more info on our centre and methodology.