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4 ways cities can become climate heroes

The possibilities are endless, but city leaders need focus.

Shining climate hope?

The US government sent an official delegation to the international climate talks this week in Bonn, Germany. This being the Trump administration, it planned exactly one public event, where it crudely hawked coal and nuclear. The panel sparked colorful protests and was generally mocked the world over.

Alongside, however, is a shadow delegation, representing states, cities, businesses, and universities — “subnationals,” in the parlance — rallying under the banner “We Are Still In.” Their aim is to stick to the US pledge under the Paris agreement, rebuking the Trump administration’s decision to withdraw. The We Are Still In Declaration now has 2,500 signatures from subnationals, “representing more than 130 million Americans and $6.2 trillion of the U.S. economy.”

But these subnationals don’t just want to make grand declarations. They’ve also launched America’s Pledge, an initiative co-chaired by Michael Bloomberg and California Gov. Jerry Brown meant to “aggregate and quantify” the contribution of US subnationals. It just released its Phase One Report, a deep look into the capacities and potential of subnationals to reduce emissions. (Spoiler: The potential is large, but probably not large enough to meet US targets without federal help.)

Leading the charge for subnationals are cities, which increasingly make up the climate vanguard. With their concentrations of population and commerce, cities are enormous sources of greenhouse gas emissions, but they have also proven (especially relative to national governments) the most dynamic and innovative sources of climate solutions.

So let’s focus in on cities. What is their ultimate potential in the climate fight? What kinds of emissions reductions are they capable of and what’s the fastest way to achieve them? Two reports help illuminate these issues, one older, one just released.

The older one, released last year, is from C40, an organization that now includes more than 90 of the world’s biggest cities, representing more than 650 million people, 20 percent of global greenhouse gas emissions, and roughly a quarter of the world’s GDP. It is called “Deadline 2020” and it’s about “the pace, scale and prioritization of action needed by C40 member cities over the next 5 years and beyond” on climate change.

And this week, research consultancy McKinsey released “Focused Acceleration,” an analysis meant to complement and extend Deadline 2020, helping cities target the highest-impact strategies based on their size and stage of development.

Both reports are enormous and incredibly granular — great reading for city staffers and leaders. I’ll just focus in on the four areas where McKinsey says cities can make the biggest impact.

Cities can achieve almost half the needed emission reductions

First, the big picture. Here is C40’s report, distilled into a single graphic:

c40 C40

“Energy decarbonization” refers to decarbonizing the energy grid, a task that C40 deems largely in the hands of state and national governments.

The rest is in the hands of city leaders — though, importantly, not only in their hands. The report estimates that roughly 20 percent of the needed actions can be taken by mayors unilaterally. The other 80 percent requires “a combination of collaboration and partnerships” with national governments and other subnational entities.

This is no small impediment. Virtually any city leader will tell you that part of their headaches come from the lack of regional planning and the lack of cooperation from state governments (in which rural interests, especially in the US, are over-represented).

Also, to get to the boasted total — 51 percent of reductions needed to get on a 2-degree trajectory — not just the C40 cities but almost every city in the world will need to act. (The C40 initiative is meant to pilot strategies in bigger, wealthier cities that can then be fine-tuned and exported to smaller, growing cities.) Here are the envisioned contributions of the world’s cities, broken down by size:


As you can see, the big target of C40’s advocacy is other big megacities, which will be expected to contribute the most reductions.

C40 groups city contributions into five categories: buildings, energy, transit, urban planning, and waste management.

McKinsey takes a slightly different perspective on the same data. It warns against the “try some of everything” approach. If city leaders drift around, changing out some street lights, opening a bike lane, creating a new transit app, they will end up producing lots of press releases but insufficient emission reductions.

McKinsey says: focus. Most of the results will come from a few top priorities.

Focused acceleration is a proven approach in the private sector. We have found companies that focus change efforts on a few big opportunities and execute them well, rather than skimming the surface of many smaller initiatives, achieve more dramatic results and do so faster.

With that in mind, McKinsey set about distilling a short list of targeted strategies for cities. “We started with the more than 450 emissions reduction actions identified in Deadline 2020,” their researchers write, “and prioritized 12 opportunities across four action areas that have the greatest potential in most global cities to curb emissions and put cities on a 1.5°C pathway through 2030.”

So what are those four action areas?

1) Decarbonize the electricity grid

McKinsey says that C40 is underestimating the influence cities have on the grid. “While cities may believe they have little influence over the grid mix,” it says, “in fact, they often represent a major portion of any local electric utility’s customers, potentially giving them significant leverage to shape the emissions profile of the electricity consumed within their metropolitan area.”

Cities’ sheer bulk gives them a great deal of leverage over utilities, but exercising that leverage, McKinsey acknowledges, means working with state regulators and utilities.

“Cities have an essential role to play,” it says, “by setting clear decarbonization goals, aggregating demand for renewables, promoting energy efficiency, and shifting more urban energy consumption to electricity (especially in transportation and heating).”

By accelerating those efforts, McKinsey says, cities could achieve “35 to 45 percent of the total emissions reductions needed [by 2030] at a cost as low as $40 to $80 per megawatt-hour.”

2) Make buildings work better

Heating and cooling the world’s buildings produces around 40 percent of global energy emissions. Years of experiments and pilot projects have shown that the amount of energy buildings consume can be radically reduced with existing technology, but when it comes to shifting from pilot projects to large-scale programs, most cities haven’t even scratched the surface.

McKinsey urges cities to take such actions as “raising building standards for new construction, retrofitting building envelopes, upgrading HVAC and water heating technology, and implementing lighting, appliance, and automation improvements.”

This too will be a bit of a slog, as it will require working with developers, real estate owners, and building occupants. But it is crucially important, because buildings are long-lasting infrastructure, averaging between 30 and 50 years, so getting them right (or wrong) reverberates far in the future.

Accelerating action in this area, McKinsey says, “can close 20 to 55 percent of the gap between current emissions trends and 2030 abatement targets, depending on the local climate and population growth of the city, at an average cost of $20 to $100 per metric ton of CO2 equivalent.”

(Many building improvements face a problem common to cleaner technologies — they cost more up front but pay off over the mid- to long-term. That means cities will also need to change the way they think and the way they finance projects.)

3) Change how people get around

McKinsey lumps together the two big related challenges of reducing transportation emissions.

The first is better urban design, increasing (livable) density. When people live closer together, they can take advantage of non-car transit modes: walking, biking, and public transit. All cities need to turn their attention to transit-oriented development and multi-modal land-use and transportation plans.

The second is pushing the transition from internal combustion engines to electric and autonomous vehicles, reducing emissions and increasing the efficiency of freight transport and delivery.

Accelerating efforts in these areas, McKinsey calculates, “can contribute emissions reductions equal to 20 to 45 percent of 2030 targets, depending on urban income levels and population density.” Such efforts will also increase the livability and attractiveness of cities and reduce local air pollution, so, win-win.

4) Use less and waste less

There are a variety of ways that cities can improvement their management of material flows, starting from the top: “first reducing waste upstream; then repurposing as much useful finished product as possible; then recycling, composting, and otherwise recovering materials for use; and finally, managing disposal to minimize emissions of any remaining organic matter.”

Organic matter emits methane as it decomposes, which is a much more powerful greenhouse gas than carbon dioxide in the short-term, so it’s key to minimize organic waste and to take steps to capture and use the methane emissions from landfills.

The ultimate goal is a “circular economy,” in which there is no waste — in which all materials can be recaptured and reused. Obviously, most cities are nowhere close to that, but it’s the North Star.

Depending on a city’s starting point, McKinsey estimates, it can get about 10 percent of its needed emission reductions from waste-management strategies.

By way of review, here is all the above, in graphic form:

mckinsey cities McKinsey

Cities are snowflakes

Every city is unique. More broadly, cities differ widely in their size, wealth, rate of growth, age of building stock, renewable resources, and innumerable other dimensions. McKinsey is at pains to acknowledge this; for every one of the focus areas above, it breaks down the different ways the strategies might apply in different kinds of cities.

It analyzes the right approach for six different kinds of cities:

  • large, middle-income, semi-dense city
  • small, high-income, innovator city
  • large, high-income, dense city
  • low-income megacity
  • middle-income megacity
  • large, low-income, leapfrog city

I won’t go into the details, but there are granular comparisons of different best practices for different cities. Your large, middle-income, semi-dense city, for instance, is going to get most of its reductions from next-generation vehicles and distributed renewables, while your small, high-income, innovator city will get its biggest results from centralized renewables and upgraded HVAC systems.

For a city nerd, it’s an easy way to lose a few hours. But the level of detail and granularity serves to highlight why the subnational route to carbon reductions is so fraught and difficult.

National governments have big levers; simple actions can move lots of emissions. For cities — even cities that focus on these 12 key areas, like McKinsey recommends — it is a matter of bricolage. It means pushing scores of policies and reforms all at once, working with (or sometimes against) state governments, business interests, utilities, residents, and nonprofit groups, often simultaneously.

Cities will need not only new policies but new procurement strategies, financing instruments, means of gathering and sharing information, and ways of engaging the public.

That’s a lot of change, a lot of reform, a lot of collaborating and bargaining and fighting, in a lot of places, all at once — and it all has to go right to achieve these massive targets.

Pledges (America’s Pledge!) and declarations (We Are Still In!) can help reduce the uncertainty in all this and help to reassure city leaders that they are not alone, that others are fighting the same fight, that there’s mutual support available.

And maybe this grassroots, ground-up route really is the only way to get to serious climate action.

But because it is so distributed, subject to so many countervailing social and economic forces, it is just wildly difficult to predict how it will go. Believing in it as city leaders seem to — believing not only in their own efficacy but in the efficacy of distributed, networked, loosely coordinated action to rival national and international action — is ultimately a leap of faith.

But I suppose faith is all we’ve got these days.

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