During the Paris climate talks, 640 Mayors gathered to announce plans for cities to deliver annual a combined annual reduction of 3.7 gigatons in emissions by 2030.

American cities are already engaging with these targets as the cities of San Francisco and San Diego have both gained approvals for climate action plans that will see emissions halved over the next 20 years.

City of San Francisco Mayor Edwin Lee announced that the city has now completely cut out the use of petroleum diesel across the city’s diesel fleet. Diesel has been replaced with Nexdiesel Renewable Diesel which claims to allow fleets to be 100% green and sustainable without suffering any operational issues.

“San Francisco and cities worldwide must continue to lead by taking bold actions that reduce greenhouse gas emissions immediately,” said Lee. “These actions cannot wait. San Francisco has ended its use of petroleum diesel to fill up the City’s fleet of vehicles and will significantly reduce greenhouse gas emissions and improve air quality for our residents immediately today.”

The renewable diesel will be used at all 53 city-run fuelling sites and across 1,966 operational vehicles. The Mayor’s office estimates that the Fleet Management Division will reduce emissions by 50% through the switch. It forms the first part of the cities pledge to cut emissions to 80% below 1990 levels by 2050.

Meanwhile, San Diego Mayor Kevin L. Faulconer’s Climate Action Plan has also received approval, which will see the city half emissions by 2035 and source 100% of its electricity from renewable sources.

“Today San Diego took a landmark step toward securing a greener and more prosperous future,” Faulconer said.

“We’ve done something remarkable, bringing business and environmental interests together in a bipartisan manner to support a cleaner community and a stronger economy. We’ve struck the right balance with this plan, and San Diegans can look forward to more clean technology, renewable energy and economic growth.”

As part of the approval process, the Mayor seeked endorsements from environmental, business and community leaders. If the targets are not met, environmental groups and even the state attorney general have been invited to file lawsuits to force elected officials to comply.

Paris legacy

Anne Hidalgo, Mayor of Paris, has been influential in getting other major cities on board with emission reduction schemes. She hosted The Paris City Hall Declaration which binds the cities to produce resilience strategies and action plans by 2020 in order to reduce the 3.7 gigatons of emissions by 2030.

City governments are able to establish pathways for transparent reporting of these goals through the city coalition the Compact of Mayors founded by Ban Ki-moon and Michael R. Bloomberg. The Compact recently named Rio de Janeiro as the first fully compliant city, which has an emissions reduction target of 20% by 2020.

The Compact of Mayors recently announced that the collective impact of its 360 city members will deliver over half of the world’s potential urban emissions reductions by 2020.

Green Capital

In the UK, the European Green Capital city of Bristol has this week made a bold pledge to accelerate its already-ambitious climate targets and pursue complete carbon neutrality by 2050.

Bristol, which gives up its title as Britain’s first European Green Capital at the year-end, has already reduced energy use by 18% and carbon emissions per person by 24% since 2005. Under its most recent climate strategy, Mayor Ferguson committed to a ratcheting of future CO2 reductions of 40% by 2020, 50% by 2025, 60% by 2035 and 80% by 2050.

Matt Mace

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