Councils 'must lower carbon emissions'
Local authorities across the UK should have a statutory duty to combat climate change, government advisors recommend.
The Committee on Climate Change says that councils can make major cuts in greenhouse gas emissions in areas such as housing, traffic and waste.
Its report says that some councils are taking action but many others are not, which threatens national climate goals.
But with many councils struggling with finance, the committee says more government support may be needed.
The committee is the government's statutory adviser on climate change, and has recommended progressively tighter carbon budgets for the UK leading towards the legally binding goal of an 80% cut from 1990 levels by 2050.
"We've got national carbon budgets with ambitious emission cuts built into them, and if we weren't to address the cuts local authorities can make, we'd not meet the targets," said David Kennedy, the committee's chief executive.
"Local authorities can have a very big impact in areas such as improving energy efficiency in buildings, sustainable travel and waste management," he told BBC News.
The committee calculates that having all councils invest in these measures will bring UK emissions down by about 15 million tonnes of carbon dioxide per year, or about 3%.
The Local Government Association (LGA), which represents the interests of councils across England and Wales, highlighted the policies that some councils have already implemented and the impacts they are having.
Bristol, for example, has set a target of reducing emissions by 40% between 2005 and 2020.
The council has cut its own energy use by nearly a third. It has invested in wind turbines, biomass boilers and solar panels for schools, and insulated 30,000 homes.
Islington in North London has set the same target. A district heating network and a zero-carbon school are among its flagship projects, while the council is also engaging with industries to reduce their emissions.
Woking is promoting cycling and developing ways to reduce the volume of waste produced, which also lowers emissions.
And Kirklees Council, which encapsulates Huddersfield, offers residents free home insulation.
The LGA agrees that local authorities can and should be major players in combating climate change, but argues that a nationally imposed statutory duty is a "blunt instrument".
Instead, it says, councils should be encouraged to make their own decisions based on local needs and local capacities.
Even so, said the LGA's senior adviser Abigail Burridge, finance would remain a major stumbling block unless the government stepped up support.
"With the massive spending cuts councils face, they're having to take very tough decisions at a local level," she told BBC News.
"Some councils have struggled to to access some of the funding pots that are there - and some things cost more in certain places, such as in rural areas where public transport costs would be high."
The committee has had no reaction as yet from government, which is however obliged to consider its recommendations.
Apart from reducing emissions, the report also notes that local authorities have the power to increase communities' resilience to climate impacts, for example through wise siting of buildings and encouraging frugality with water.
Earlier this week, the European Environment Agency said councils had to show leadership in this area, adding that the costs of taking action would quickly be outweighed by the costs of not doing so.
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