The government agency said that trucks were behind what they estimated was a 0.5 percent rise in emissions during 2018. That amounts to 76,000 more tonnes of carbon dioxide, after several years of a steady fall in these emissions.
When it came to passenger cars, there was a higher proportion of energy-efficient vehicles on the roads last year. But an increase in the number of trucks on the roads meant that overall Sweden is a long way from reaching its emissions target.
This was exacerbated by the fact that while the number of passenger vehicles on the roads remained stable last year, truck traffic increased by three percent year-on-year.
In order to reach the goal set by the Swedish government of a 70 percent reduction in greenhouse gas emissions from traffic by 2030, an eight percent annual decrease is needed. Based on current figures, the Transport Administration estimates that Sweden will only reach half the target reduction.
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"We need to increase the pace if we are to meet the climate target," said Marie Hagberg, head of the traffic quality department at the Transport Administration. "In addition to stricter instruments for more energy-efficient vehicles and an increased proportion of renewable energy, this means more public transport, walking and cycling [opportunities] in densely populated areas. When it comes to freight traffic, it means having longer, heavier, and in the long term fewer trucks and transporting more goods by rail or boat."
In July last year, a new law was introduced to give motorists a monetary bonus for buying cars with low emissions, and higher taxes for new cars that use a lot of petrol and diesel. The number of hybrids and electric cars registered on the road increased last year, but in total accounted for 27,000 vehicles, while more than 300,000 new petrol or diesel-powered cars were registered.
Hagberg also noted that the average carbon dioxide emissions from cars increased, which she called a "worrying development".
Göran Finnveden, a professor of environmental strategic analysis at the KTH Royal Institute of Technology, said that a lot of public focus on reducing emissions has been put on passenger cars, while the impact of trucks and freight transport is addressed less often.
"This may be because there are such strong industrial interests in this, and therefore it's been more difficult to work on," he told the TT newswire.
He also warned that current infrastructure planning across the country focused on expanding roads rather than improved public transport networks, which seemed to run counter to the climate goals.
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