London — LED streetlights, roof-top solar water heaters, and a push for Cape Town to get a fifth of its energy from renewables by 2020
National leaders may have been the ones to sign the Paris Agreement to combat climate change - but when it comes to putting the deal into effect, "it is cities that drive most of the change", says Cape Town's mayor Patricia de Lille.
Since taking charge of South Africa's second biggest city in 2011, her administration has overseen the installation of LED streetlights on 25,000 roads, retrofitted 32 city buildings to make them more energy efficient and installed 46,000 roof-top solar water heaters.
A big plot of land in the city has been set aside for green companies that want to move in and build solar panels, wind turbines or other forms of clean tech.
Already U.S. electric car manufacturer Tesla has indicated it intends to open its first Africa office in Cape Town, de Lille said, and a Chinese manufacturer of solar-powered electric buses will come in next year.
Cape Town has an order in for 10 of the buses, the first of which will hit the streets later this year, she told the Thomson Reuters Foundation in a telephone interview.
"They're going to save us a lot of money," said de Lille, 66, a former trade union leader and longtime South African politician.
"Our maintenance budget will be cut by 60 percent, as they're very easy to maintain. And to recharge the batteries we're also going to use solar energy."
Around the world, cities are increasingly at the forefront of action to curb climate change - and a growing number, from Cape Town to Paris to Sydney, are now run by women.
In two years, the number of women in charge of large cities leading on climate action has risen from four to 16, according to the C40 Cities network of more than 80 cities committed to addressing climate change, which is organising a conference for women leaders in New York this month.
De Lille said that women leaders are far from "the panacea for all of our problems". But when it comes to climate change, "you always see it is girls and mothers who are disproportionately affected. As women, we have to represent those voices of other women".
The poor in Cape Town have much to lose if climate change is not effectively dealt with.
Worsening flooding has hit the poor particularly hard, she said, and now extended drought - the worst in 100 years over the last two winters - has left the city's main water supply dam at just 23 percent of capacity. That is water for just 121 days, the mayor said.
The seaside city is looking for more water where it can - recycling water, treating effluent and pumping it back into the dam, tapping into old springs under the city and testing out desalination. But the solutions need to keep the poor in mind, de Lille said.
"Desalination is very expensive and once you go for expensive infrastructure and operating costs, it will put up the price of water" - something she would like to avoid, she said.
RENEWABLE AMBITIONS - AND OBSTACLES
One of de Lille's key ambitions is to see Cape Town get at least 20 percent of its energy from renewables by 2020 - just three years away. Independent solar and wind power producers, hoping to feed energy into the national grid, have sprung up, including in Cape Town.
But Eskom, the national company that produces 95 percent of South Africa's electricity, has yet to sign agreements to purchase much of the renewable power, arguing the deals could put Eskom's finances at risk.
The company is waiting for the completion of two big and years-delayed coal-fired power plants it is building, designed to reduce energy shortages in the country.
The impasse has so far limited Cape Town's ability to source renewable power - and has led de Lille and the renewable energy firms to threaten lawsuits.
"I don't think they've got a right to block me buying clean renewable power from any independent power producer," the mayor said.
De Lille said that she's seen little pushback on her clean energy agenda at home and that, like many mayors, she spends her time focusing on "implementation, implementation, implementation".
"In government, things don't just happen by wishing," she said. But with good leadership, "later on, you find that people have now bought into the idea and understand the benefit of what we are achieving. Then it's much easier - you have leadership at all levels bought into the new way of doing things."
One thing she wishes she had, however, is more money. International funding to help developing countries address climate change is only slowly getting flowing and what arrives at the national government level does not always trickle down to cities, she said.
To change that, the world's mayors should work together "to say to these multilateral bodies that we want a say in how the resources are distributed", she said.
De Lille's term as mayor ends in 2021 - one reason her renewable energy goal is set for 2020.
"I'm going to push as hard as I can to get all or most of my targets embedded in this city so no one can change them again, so they can just come in and build on that," she said.
With climate change impacts worsening fast and few years left to bring about a wholesale shift to clean energy, "there's no time for trial and error", she said. "We have to make sure we do it right the first time."
- Reporting by Laurie Goering @lauriegoering; editing by Alex Whiting