Why we’re right to be worried about air quality – and how renewables can help

2/08/16 | Blog

Today, Scottish Renewables launches its first ever Low-Carbon Cities Conference.

With air quality at the heart of urban health, Director of Policy Jenny Hogan reflects on six decades of the Clean Air Act - and asks what more needs to be done.


Sixty years ago, the UK’s cities laboured under a toxic cloud of foul air.
The London smog of December 1952 killed an estimated 12,000 people, and was so dense that cows reportedly choked to death in their fields.

Today, thanks in part to the revolutionary 1956 Clean Air Act, which celebrated its Diamond Anniversary last month, we can breathe much easier.

But the issue of air pollution hasn’t gone away – as the world was reminded by last year’s diesel car emissions scandal.

Renewable energy’s most well-known contribution to the cleaning-up of our atmosphere is its remarkable success in reducing air pollution and cutting carbon dioxide emissions.

In Scotland alone, our industry now displaces 12 million tonnes of carbon every year – the equivalent of taking every car, bus, lorry and train off our roads and rails.

Additionally, emissions of Nitrogen Oxides, Sulphur Oxide and particulates – tiny particles which enter our lungs and can cause diseases like cancer – have fallen as we’ve moved away from polluting fossil fuels.

Now, new technology offers us the chance to do even more.

Fuel cells, like those being pioneered by Renfrew business Doosan Babcock, offer low-emission electricity from natural gas, and zero-emission electricity from renewable biogas or even hydrogen.

They are already generating power in crowded, urban areas: Transport for London’s offices and US corporates like Coca Cola, Google and Amazon all use fuel cells, although wider take-up in the UK has been limited so far.

The air pollution issue doesn’t end with electricity generation, however.

Pollution from road traffic still kills more than 2,000 Scots every year.

London exceeded air pollution limits for the entire year in the first eight days of 2016, prompting new Mayor Sadiq Khan introduce new powers to curb transport pollution.
And while local authorities in Scotland have the power to set up Low Emission Zones, none have yet done so.

About 60% of carbon pollution from the transport sector comes from passenger vehicles, so hydrogen or electric vehicles and a clean grid can make a big difference in tackling climate change and improving air quality.

Using electricity from renewable sources (either directly, or indirectly through hydrogen) to power our transport needs is a clear winner: zero emissions when the ‘fuel’ is produced, and ditto at the exhaust pipe.

An example: Typically electric trains emit between 20-35% less carbon per passenger mile than diesel trains.

ScotRail’s ongoing work to electrify the Glasgow-Edinburgh rail line will cut emissions from diesel locomotives both along the track and in the enclosed terminus stations, improving the health of commuters, rail workers and those who live near the tracks.

But the problem of air quality goes beyond transport.

Half our energy demand is in the form of heat, and most of that comes from burning gas.

Research by Kings College London found that by 2025, 48% of total NOx emissions in the capital could come from burning gas for heat.

Technologies like heat pumps, fuel cells and solar thermal panels can help us wean ourselves off fossil fuelled heat, without producing harmful emissions at source.

Heat pumps, like those made in Glasgow by Scottish Renewables member Star Renewable Energy, act like a fridge in reverse, using small amounts of electricity to compress ‘low grade’ heat from water, ground or air and turn it into warmth for homes and businesses.

Tie these newer technologies, either individually or in combination, into district heating schemes – where multiple properties are heated by one communal heat source – and both the air quality improvements and carbon savings can be significant.

Renewable energy is already cutting harmful emissions from our power sector.

Now it’s time to step up a gear and tap the potential these clean, green power sources have for our heat and transport sectors too.

Blog by Jenny Hogan, Director of Policy, Scottish Renewables