London scoping - ukcip

6.14 Clean City
Final Report
135
6.14.1 Context
The MORI survey (2001) for the GLA on public perceptions of living in London revealed that
air pollution was regarded as the second most serious problem for London out of a list of 8
environmental issues (63% of respondents regarding it as a problem, and 14% not regarding it
as a problem). Furthermore, when asked whether London is a ‘clean city’, nearly three quarters
of respondents disagreed, and only 19% agreed. Section 5 has illuminated some of the potential
decreases in air quality for London arising from climate change. Given the high starting
baseline of air pollution problems, that they may get worse given climate is of huge concern in
terms of health and also for the image of London as an attractive place to live, work and visit.
Natural ventilation approaches to cooling of buildings will be less attractive if there are higher
levels of external air pollution, hence encouraging higher uptake of air conditioning, feedingback
to higher energy consumption and more urban waste heat.
6.14.2 Temperature Change Impacts
Household and commercial rubbish will decay more rapidly as a consequence of higher summer
temperatures. This would increase the smell of rubbish, reducing the attractiveness of the city
for its inhabitants and visitors. Changes in collection routines, with perhaps more frequent
collections, might well be required. Hosing-down of streets is also likely to be required given
hotter conditions, especially if there are higher levels of dust in the air, due to construction work
or blowing in of dust from land. Yet, more street cleaning means more water consumption,
putting greater stress upon limited water resources. The opportunities for utilising recycled
waste water for street cleaning are evident.
6.14.3 Socio-Economic Scenario Differences
There could in fact be quite significant differences in air pollution arising between the two
scenarios. One optimistic vision of Global Markets would see a transition to fuel cells, which
would eventually replace the internal combustion (IC) engine. Fuel cells produce fewer noxious
emissions. If hydrogen were the fuel of choice, then the principal by-product would be water
vapour (with very limited emissions of other gases). If methane were the fuel used in the fuel
cell, the emissions could (depending on the precise system) consist of by-products such as SOx
and NOx. The greater efficiency of fuel cells compared to the internal combustion engine
means that the actual emissions would be significantly lower than cars running on petrol (at
least 50% lower per km). The wide-spread penetration of fuel cells in private cars, buses and
even trains could have a significant benefit to the air quality in London, since much of the air
pollution is currently related to use of the internal combustion engine. A less optimistic vision
of GM, would not envisage replacement of the IC engine because less emphasis would be put
on regulation of air pollution, reducing the incentive to develop fuel cell technology and
associated infrastructure.
Under Regional Sustainability, we would see increased use of policy instruments at the cityscale
to limit use of private cars, e.g. car zoning, charging schemes, availability of parking
spaces, etc. There would be increased investment in public transport, especially buses (which
are already used more heavily than elsewhere in the UK). One interesting aspect of the RS
scenario is that we would not necessarily see a rapid development of fuel cell technology. This