Science

'Zero-emissions' building sites ditch diesel machinery in Oslo, Norway

A nearly "zero-emissions" building site in Oslo, using electric machinery, could be a pioneer for greener construction as the world's urban areas swell by the equivalent of a Dublin or Dallas every week, city experts say.

Plug-in diggers, stone-cutting saws, other electric machinery used in 'groundbreaking' Oslo project

An electric digging machine works on a pioneering ‘zero-emissions’ building site in central Oslo this past June. The pedestrian area in the center of the Norwegian capital is expected to be completed in time for Christmas. (Alister Doyle/Thomson Reuters Foundation)

A nearly "zero-emissions" building site in Oslo, using electric machinery, could be a pioneer for greener construction as the world's urban areas swell by the equivalent of a Dublin or Dallas every week, city experts say.

Plug-in diggers, saws for cutting stones and other electric machinery have been used to create a pedestrian area in the center of the Norwegian capital — completed in time for Christmas.

The shift aims to help curb climate change, air pollution and noise, officials say.

C40 Cities, a network of almost 100 of the world's biggest cities working to slow climate change, called the diesel-ditching project by the left-wing municipality "groundbreaking and unprecedented worldwide."

"Many cities are looking to Oslo to learn," said Cassie Sutherland, program director for energy and buildings at C40 Cities in London.

Sitting in chill winter sunshine at the Oslo site, on a new wooden bench by a flower bed planted with purple heather, project leader Marianne Mølmen of Oslo's Agency for Urban Environment said the revamped street "has become really great."

The area, lined with shops, cinemas and bars — many closed due to coronavirus — also has new bicycle parking racks and tree saplings. Fossil-fuel cars have been banned in much of the area, which includes special chargers for electric taxis.

Environmental benefits, extra costs

Mølmen said the revamp project, which began in 2019, saved 35,000 litres of diesel fuel and 99 per cent of greenhouse gas emissions compared to a conventional building site.

The project cost 64 million crowns ($9.4 million Cdn), compared to an estimated 59 million ($8.7 million) for a more traditional project, largely because electric machines are scarce and currently cost more.

The "zero emissions" standard used was more stringent than a previous "fossil-free" regulation in Oslo that allowed the use of biodiesel engines.

Norway generates almost all its electricity from hydropower.

Marianne Mølmen, project leader at Oslo’s Agency for Urban Environment, said the revamp project, which began in 2019, saved 35,000 litres of diesel fuel and 99 per cent of greenhouse gas emissions compared to a conventional building site. (Alister Doyle/Thomson Reuters Foundation)

Oslo leads the global "clean construction forum" for C40, whose members include big cities such as Beijing, New York, Tokyo, London and Paris.

In one C40 initiative last month, Oslo, Los Angeles, Mexico City and Budapest jointly pledged to halve emissions from building sites by 2030.

The world's construction industry accounts for more than 23 per cent of global greenhouse gas emissions, C40 said, so any cuts will help nations meet goals they set in the 2015 Paris climate agreement to limit global warming.

And urban areas, especially in developing nations, are expanding at breakneck pace.

The U.N.'s panel of climate scientists said in its most recent assessment in 2014 that more than half of the world's population lives in urban areas "and each week the global urban population increases by 1.3 million."

That means adding urban areas the size of Islamabad, Harare, Dublin or Dallas every week or so.

Priorities for green construction

Sutherland at C40 said priorities for green construction include upgrading existing buildings, rather than demolishing and re-building, improving designs and using better materials, such as recycled steel or low-emissions concrete.

Oslo's "zero emissions" policy seeks to cover all work within the perimeter of building sites. But a lack of specialized electric machinery from suppliers means the municipality sometimes grants exemptions and permits machines that use fossil fuels.

Plug-in diggers, saws for cutting stones and other electric machinery replace diesel at city-run construction sites. However, the city doesn't have authority over private construction sites. (Alister Doyle/Thomson Reuters Foundation)

In its recent project, the municipality allowed a diesel crane onto the site, for instance, after failing to find an electric one. It burned 16 liters of fuel. Also, asphalt laid at the site was by diesel-powered machines.

Among suppliers, Norwegian construction equipment producer Nasta refits excavators built by Hitachi with batteries, enabling them to operate for about four hours before running flat.

Norway, western Europe's top oil exporter with a $1 trillion sovereign wealth fund built on fossil-fuel wealth, paradoxically also has some of the globe's most progressive environmental policies.

Those have created, for instance, the highest rate of electric car ownership in the world. In the first 11 months of 2020, 52 per cent of all new cars sold in Norway were electric, according to the Norwegian Road Federation.

Oslo' vice mayor Lan Marie Nguyen Berg, of the Green Party, said cities can often be more ambitious than national governments because voters see the results of climate policies in their daily lives — more parks, cleaner air and cycling lanes.

Oslo was named Europe's Green Capital for 2019 by the European Commission.

Private sites exempt from zero-emissions requirements

A problem is defining where the city's authority ends and less-stringent national building codes — which allow fossil fuels — take over.

Currently, Oslo only demands emissions-free construction on sites it controls, from roads to kindergartens.

"Four of five construction sites in Oslo are private or state owned," Berg said, adding the city recently wrote to the center-right government saying it wanted to demand that all sites in Oslo are zero-emissions or fossil-free.

It has not yet received a reply.

Among other green changes in the city in recent years, the percentage of electric vehicles passing toll points into Oslo has risen to 25 per cent of all cars from 6 per cent in 2015. Diesel cars pay a toll five times higher than electric cars.

The municipality has built 55 kilometres of cycling roads since 2015, after only about 15 kilometres were added in the previous decade. More than 100 electric buses operate in Oslo and surrounding areas.

Those changes have stirred hostility from some car drivers. A new single-issue party, campaigning to abolish road tolls, won nearly 6 per cent of the vote in 2019 municipal elections in Oslo.

Despite its greener policies, Oslo has fallen far short of a headline-grabbing goal in 2016 to halve the city's greenhouse emissions by 2020.

Under revised, less ambitious goals, Oslo estimates emissions in 2020 will be 25 per cent below 2009 levels, which were about 1.4 million tonnes.

Berg said a lack of government funding for carbon capture and storage — used to catch emissions and trap them permanently underground — at a municipal waste plant partly explains the shortfall.

Revisions to historic emissions data also have played a role, she said.

She reaffirmed a goal to cut emissions 95 per cent by 2030, compared to 2009 levels.

"We will get there but it will also be hard work," she said.

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