What will it take to make the city regenerative?

When compared to rural regions, cities are remarkably resource and energy efficient; they retain heat and cold far better than single houses exposed to the elements, and most amenities can often be found within easy walking or cycling distance, reducing the need for motorised transport. For travelling over longer distances, cities usually offer communal transport systems that require less energy per passenger than personal cars, while also often being electrified. Cities also take up less space per capita than suburban or rural housing, leaving more overall space for other uses.

Still, it cannot be denied that cities put a significant strain on the environment due to their high concentration of human activity and intensive use of resources and energy. This is especially pronounced in the megacities of the world. Take, for instance, Beijing. The groundwater level below the Chinese capital has dropped 20 metres since 1980, and nearly 40% of Beijing’s surface water is too polluted for human use. Consequently, the city has 70% of its fresh water piped in from southern China, more than 1,000 km away – and water scarcity is still a major problem.(1) The city also suffers from major smog problems. During the corona lockdowns last spring, air quality rapidly improved in Beijing (as it did in most larger cities) due to the general slow-down caused by the virus. But the joy was short-lived, and already in late-September 2020, air pollution was back to pre-lockdown levels.(2)

Although the environmental problems facing megacities like Beijing are severe in scope, they are shared by cities?across the world. The environmental strain that urban environments put on natural ones will only become more evident as cities grow in size and number, and as their energy and resource use intensifies. Urban resource and energy use can unquestionably be reduced with improved efficiency and more recycling. But for cities to become truly resource-efficient and low carbon emitting while positively enhancing – rather than undermining – the ecosystems they depend on, we will need to look beyond ‘green’ initiatives and incremental improvements.

Behavioural change is needed - but it won't be enough

The regenerative city is, at our present time, more of a moonshot ideal than a practical, achievable goal, and we do not yet know how to achieve it. However, we do know that on a global scale, reaching a regenerative state at some point is a necessity. The question is not so much IF cities should become regenerative but rather WHEN. In the longer term, it may be possible to move toward the regenerative city through a mixture of applied technology and innovative infrastructure. Such solutions are feasible, but to make a city regenerative in the economic as well as the technical sense, any measures will also have to be economically viable for businesses and public finances. Finally, the most important part of a city is the people living and working there. In order to create a thriving regenerative city, you must make people want to live in it – make it desirable.

On top of this comes the challenge of making us all act in a manner that aligns with these ideals. This may well prove to be the hardest step in a regenerative transformation. Most of us want to do the right thing, but we often tend to miss the overall picture and end up doing what feels right rather than what is right. As the author of Designing Regenerative Cultures Daniel Wahal writes, in an upstream from the environmental crisis lies a crisis of perception.(3) Given the complex interwoven systems that the regenerative principles seek to tackle, knowing what the right choices are is not always easy and can be counterintuitive. For a citizen-consumer, it may seem better for the environment to ‘buy local’ because reduced transport means reduced energy use. However, if producing goods far away can be done more sustainably than locally, it may be better for the environment to import the goods. Such issues can be very complex and cannot be contained in a simple ‘thou shalt not’ commandment.

Although more sustainable consumption can no doubt take us some of the way – granted that what constitutes sustainable consumption can be made transparent for the consumer – it is only one step on the long rocky road toward the regenerative city. It arguably necessitates that the regenerative approach first becomes economically viable. To this end, carrot-and-stick measures can be a key enabler. The ‘stick’ could be measures like carbon taxing, which makes it economically desirable to cut down on carbon emissions – and even more desirable to achieve net negative emissions – while the ‘carrot’ can be rewards for regenerative behaviour, such as turning waste-to-value. Today, there are some obvious discrepancies in how we value and price consumer goods with the externalities, such as the hidden environmental costs that are a consequence of production not being factored in. A carbon tax could take us some of the way in minimise some of these discrepancies. In 2019, four former chairs of the US federal reserve and 27 Nobel laureates signed a statement saying that ‘a carbon tax offers the most cost-effective lever to reduce carbon emissions at the scale and speed that is necessary. By correcting a well-known market failure, a carbon tax will send a powerful price signal that harnesses the invisible hand of the marketplace to steer economic actors towards a low-carbon future.’

Looking beyond carbon taxing, conscious consumption and behavioural nudging, the complexity inherent in a wholesale transformation of the city’s conventional flows into circular and regenerative flows is so great that it would be impossible to provide a precise road map or summary of what individual steps this journey would take. Still, we must begin somewhere. While recognising that a central principle of the regenerative city is that systems need to be devised in a holistic and interconnected way, for the sake of simplicity we can isolate some specific areas that will be of special significance in future regenerative transformation: 1) making agriculture regenerative, 2) better use of new (and old) energy-efficient materials, and 3) redesigning infrastructure. In no way do these areas, especially viewed in isolation, represent an exhaustive list of potential solutions or a ‘guide to regeneration.’ But granted how central each of them is to the functioning of any modern city, solutions within each of the three categories will no doubt be fundamental to any regenerative urban transformation.

Making agriculture regenerative

One area where major change will be needed in a push towards regeneration is agriculture. While only a very limited amount of food is produced in cities themselves, large urban populations have a major indirect impact in terms of consumption. The IPCC has found that 23% of global greenhouse gas emissions are directly related to agricultural production.(4) Regenerative agriculture, already a core principle for many smallholders around the world,(5) aims to change this. In short, making agriculture regenerative means adopting a set of practices focusing on topsoil regeneration, increasing biodiversity, improving the water cycle, enhancing ecosystem services, supporting biosequestration (improving the ecosystem’s ability to capture and store carbon), increasing resilience to climate change and strengthening the health and vitality of farm soil.(6) Studies suggest that while regenerative agriculture is good for soil health and biodiversity, it is less clear whether changing to no-till practices (growing crops without disturbing the soil) in causes an accumulation of organic carbon in soil practices, as some proponents of regenerative agriculture have claimed.(7) However, regenerative agriculture may still benefit from genetically modified (GM) crops that produce higher yields, improve photosynthesis or capture more CO2 in the soil.(8) While GM is generally seen as an antithesis to organic farming, a combination of the two is likely needed to achieve true regenerative agriculture at a scale required to support larger cities. The question is if consumers will accept GMO as something that can be good for the environment. Another question is how well regenerative agriculture will scale. Can it be applied at a level that can accommodate a sizeable portion of the massive and growing food demand generated in cities today and in the future?

While there is no clear answer to this question of scalability, an interesting (and perhaps surprising) example in this discussion is Havana, Cuba. Driven by necessity, the city has fostered a kind of low-tech approach to urban food production which has a lot in common with the principles underlying regenerative agriculture – including high yield with minimal external inputs, a low distance from crop to consumer, and a reliance on organic fertilisation and sustainable horticultural practices.

Following the 1991 collapse of the Soviet Union, which deprived Cuba of its main trading partner, Havana was left with an acute need to produce high agricultural yields with minimal use of external inputs such as agrochemicals derived from fossil fuels. A national programme was developed to support organic food production in urban areas, and today, more than half the area of Havana Province is used for smallholder urban food production, with half of the produce being sold through local sales points. Every city is different, and Havana’s success with urban agriculture cannot be disentangled from the country’s particular political (and geopolitical) circumstance – and for that reason it may be hard to replicate elsewhere. Still, according to the Food and Agriculture Organization of the UN (FAO), Havana could provide inspiration for other countries and cities attempting to make the transition to sustainable crop, livestock, forestry and fisheries production.(9)

While Havana represents a low-tech and local approach to regenerative agriculture, experiments are underway that aim at applying it on a bigger commercial scale. The US-based food company General Mills have launched pilot programmes with the goal of turning 1 million acres of farmland in the US and Canada into regenerative farming by 2030 through promoting soil health, biodiversity, cow and herd well-being, and farmer economic resilience while maximising water use.(10) Others are taking a more high-tech approach. Danone and Microsoft have launched a programme to support start-ups developing sustainable food and regenerative agriculture solutions using artificial intelligence, robotics and cloud computing to improve agricultural systems and the food value chain through a tech-driven ‘full ecosystem approach’

Using new (and old) energy-efficient materials

When discussing technology in relation to climate change, an often-overlooked fact is that most of the technology needed to ‘solve’ the crisis already exists. The challenge lies in making those technologies feasible on a large enough scale and creating economically viable products and solutions for organisations, governments, individuals and cities to start applying them, all while creating the change desirable for everyone. This is also true when it comes to construction materials, an area that is particularly relevant considering the world needs to build two billion new homes over the next 80 years to accommodate for population growth.(12)

Many of the ‘new’ construction materials that could be used in a future regenerative transition are in fact centuries old. Take concrete, for example. This ancient construction material was invented by the Romans, but they used a very different sort from what we use today: stronger, more durable and – most importantly – with a much smaller climate footprint. The use of modern concrete is responsible for 8-10% of global CO2 emissions, largely due to the use of Portland cement as a binder. Roman concrete instead uses a mix of 90% volcanic ash (pozzolan) and 10% lime, causing minimal environmental impact. Moreover, there are plentiful sources of pozzolan around the world.(13) Wood is another climate-friendly building material, working as a carbon sink. When growing, trees absorb CO2, and this CO2 is stored in the planks and beams used for construction. This makes wood a potentially carbon-negative building material, depending on the resources used for cutting and treating the wood, and how locally the wood can be sourced.

Trees, however, grow slowly, and other plants may offer better alternatives. One is industrial hemp, which is among the fastest-growing plants in the world. A hectare of hemp absorbs four times as much CO2 per year as a forest hectare, and hemp can be used for a variety of high-quality materials including rope, textiles, paper, “hempcrete”, a lightweight, fire-resistant, mould-resistant building material and ”hempwood”, an alternative to oak planks.(14) Planting hemp and other fast-growing industrial plants like kenaf and bamboo around cities can provide a source of carbon-negative materials to replace current less climate-friendly materials. While trees grow slower and absorb less CO2, planting forests can regenerate biodiversity while also providing more green spaces for urban populations.

As cities make up two-thirds of the global energy use, much can be gained by making this energy carbon-neutral and its use more efficient. In terms of efficiency, insulation can reduce energy use for heating and cooling, but phase-change materials (PCMs) can actively regulate temperature at zero energy cost. Transitioning materials between liquid and solid states requires a lot of energy, and this fact can be used to keep temperatures in a build-ing close to a threshold temperature. When temperatures pass this threshold, excess energy goes to melt the PCM in the walls or roofs rather than raising the temperature further, and when temperatures drop below the threshold, the PCM absorbs the cold by solidifying. Several commercial PCM insulating materials are made for a?variety of threshold temperatures, and while they don’t work well in very cold or hot climates, PCMs can save a great deal of energy for heating and cooling.(15) Other similar materials such as vanadium-coated smart glass, as well as thermochromatic and photochromatic glass, provide climate-friendly alternatives for regulating indoor climates.(16) In fact, cities may be able to achieve energy-positivity through energy-producing technologies. More subtle alternatives to rooftop solar panels include photovoltaic tiles and window glass that are indistinguishable from normal inactive surface materials.(17) While these alternatives have some benefits, such as the possibility of scaling, they are not at the right level for widespread deployment yet.(18)

Redesigning infrastrucutre

Building or expanding cities in ways that include large green areas home to farmland, wilderness, recreational areas, wind farms, and solar parks can be beneficial for food and energy supply along with biodiversity and citizens’ mental health. One oft-cited example of such urban development is Copenhagen, Denmark, where city planners introduced a long-term strategy in 1947 called the ‘finger plan’. Rather than letting the city grow unrestricted into an urban sprawl, all citizens should live close to forests and rural areas. The city and its suburbs would only be allowed to grow in ‘fingers’ along railways and motorways, and between the fingers, farmland and forests were preserved or established.(19) Nowhere in the city do you need to cycle more than 15 minutes to get to a beach, a forest, a farm or all of these.

A similar example on a larger scale is the Randstad region in the Netherlands, consisting primarily of the four largest Dutch cities (Amsterdam, Rotterdam, The Hague and Utrecht) and their surrounding areas. The name Randstad (Rim City) refers to how the urban areas form a ring around a large rural area of farmland, dotted with lakes, forests and small towns called the Green Heart.?As with Copenhagen, you do not have to travel very far from anywhere in Randstad to arrive at a large, green spaces. Despite being one of the densest populated countries in the world, the Netherlands is the world’s second-largest exporter of food, showing that even very densely populated regions are able to grow more food than they consume.

Copenhagen and the Randstad cities are also famous for their cycling infrastructure, with wide bicycle paths, often isolated from motorised traffic, in the cities and connecting to the suburbs.(20) Copenhagen and Randstad could be called ’cellular cities’ because the urban areas form ’cell walls’ around green ’plant cells’. They are still far from being truly regenerative, but great steps are taken, especially when it comes to energy. Between 2008 and 2019, the Netherlands doubled its share of energy from renewable sources and the country aims to reduce its?greenhouse gas emissions by 49% by 2030 and by 95% by 2050, compared to 1990 levels.(21) In 2019, 50% of electricity in Denmark came from wind and solar, and the country aims to reduce greenhouse emissions by 70% by 2035, compared to 1990 levels. In fact, Copenhagen aims to be carbon-neutral by 2025.(22) Energy generation obviously plays an important part in achieving these goals, but measures to reduce energy use may be just as important. Infrastructure that moves personal transport from private cars to bicycles and collective transport can be important to achieve this.

One example of ambitious urban design centred around regenerative principles is ReGen Villages, a Danish startup which was recently dubbed the ‘Tesla of eco-villages’ by Business Insider.(23) The company designs small town-communities from the bottom-up which are self-sufficient in a range of areas, and which follow five principles: energy positive homes, door-step high-yield organic food production, mixed renewable power and storage, water and waste recycling. With plans for each village to be able to eventually sustain 100 families on 50 acres of land, the project is relatively small-scale, and it remains to be seen how their underlying principles can be scaled to fit more densely populated areas.

Closing thoughts

Making cities regenerative is a massive undertaking that will not be achieved overnight. Yet even the biggest undertakings can be broken down into steps; in this case, the first necessary step is developing a thorough understanding, both practical and theoretical, of how regeneration can be achieved, in which areas it is most feasible, and in which other areas it might present more of?a challenge. Reaching a goal means knowing where to aim in the first place.

The density of cities is a large factor in reducing resource use. For this reason, regenerative cities could be designed to increase population density, for example by building tall rather than wide and by favouring shared spaces and facilities over personal spaces and facilities. When combined with the idea of cellular cities, the regenerative city of the future could take the shape of thin and tall ‘walls’ between green spaces, with little or no suburban sprawl as we know it today and rapid communal transport always within easy walking distance.

It would not only take the application of new technologies to aid us in this quest toward regenerative cities, but also a tremendous shift in mindset and culture to act more responsibly as citizen-consumers. Ultimately, a lot will also depend on international institutions and cross-city collaborations to get it right. As Johan Rockstr?m, director of the Potsdam Institute for Climate Impact Research, has said: 'It’s difficult to see if the current GDP-based model of economic growth can go hand-in-hand with rapid cutting of emissions.'(24) It is often argued that GDP is a poor measure of wealth and growth because it does not properly compensate for environmental costs. While this argument has merit, if consumers are willing to pay a premium for sustainable products and services, we may be able to achieve sustainable growth even by traditional measures like GDP. And this could be a big step in our road toward the Regenerative City.

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Sources

1 Ayla Ritter: “Water-Stressed Beijing Exhausts Its Options”, Circle of Blue 2018, bit.ly/3dpzAoA.

2 https://airqualitynews. com/2020/09/24/ air-pollution-in-worldsmajor-cities-back-topre-lockdown-levels

3 Daniel Christian Wahl: Designing Regenerative Cultures, Triarchy Press 2016.

4 Climate Change and Land, IPCC special report 2020, bit.ly/3dX4c0Y.

5 www.chr-hansen. com/en/sustainability/ partnering-for-impact/ regenerativeagriculture.

6 en.wikipedia.org/wiki/ Regenerative_ agriculture.

7 Janet Ranganathan, Richard Waite, Tim Searchinger & Jessica Zionts: ”Regenerative Agriculture: Good for Soil Health, but Limited Potential to Mitigate Climate Change”, World Resources Institute 2020, bit.ly/3bMV5NL.

8 Daniel Norero: ”GMO crops have been increasing yield for 20 years, with more progress ahead“, Cornell 2018, bit.ly/3bQ3pMF Julia Rosen: “Scientists improve on photosynthesis by genetically engineering plants”, PhysOrg 2019, bit.ly/3kArX04 Emily Dreyfuss: “The Plan to Grab the World’s Carbon with Supercharged Plants”, Wired 2019, bit.ly/2PijDGR

9 FAO: “Havana - Growing greener cities in Latin America and the Caribbean”,?bit.ly/3vV7iJq.

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11?Katy Askew: www.weforum.org/ agenda/2018/03/ the-world-needs-tobuild-more-than-twobillion-new-homesover-the-next-80-years

12 www.weforum.org/ agenda/2018/03/ the-world-needs-tobuild-more-than-twobillion-new-homesover-the-next-80-years

13 Paul Preuss: ”Roman Seawater Concrete Holds the Secret to Cutting Carbon Emissions”, Berkeley Lab 2013, bit.ly/3dvVHKb

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