Partner: Atkins

At the heart of Dubai is the Sheikh Zayed Road. It drives through the city: an artery that pumps eight lanes of cars in each direction. It is easier to cross by taxi than it is to attempt on foot and this lack of walkability is a famous characteristic of the city that is sometimes called ‘the Pearl of the Gulf’.

Dubai hardly stands alone in this. Although ancient or Medieval city centres are often compact and full of life, the population boom following the Second World War has seen people in the developed world confined to residential districts. Urban sprawl moves people further from workplaces, amenities, and each other. It has all been enabled by the automobile.

Times are changing, however. Even Dubai has built a neighbourhood called ‘Sustainable City’. It is home to Matthew Tribe, Managing Director for Planning, Design and Engineering at SNC-Lavalin.

“I used to live in the typical gated community here. Big cars, big double garages, detached and semi-detached villas. And because of the [hot] weather, I never met anyone. I went from on air-conditioned environment to another air-conditioned environment,” says Tribe.

Tribe is interested in the planning of urban environments, and also made the decision to move to Sustainable City a few years ago. It is a walkable environment with cars use restricted inside the neighbourhood. One of the most noticeable features is a ‘green spine’ through its centre, providing lush landscapes and a number of biodomes and vertical farms.

“I moved to explore the impact of [living in] a different kind of residential model, where in the centre of the development is car free. All the properties have photovoltaics on the roof, they have grey water recycling,” says Tribe. The car parking areas outside of the development also have solar panels, so we all have very cheap utility bills. But the level of community engagement and social interaction is incredible.”

This liveability on the individual level is going to be very important. Tribe spends a lot of time thinking about the future of urban environments. And although this field considers the future of cities of millions, it needs to take into account the experience of individuals.

Working with what we have

In this article we are thinking about Masterplanning. Exactly how we develop our cities to cope with current and future challenges.

Our urban centres will have a critical part to play in our response to the climate emergency. But how they can be leveraged to do this will be fiendishly complex. It will take numerous disciplines across the built environment working in concert. Because this is not a question just of incorporating clever technology, or even of a utilitarian town plan drawn up by a gifted architect. Nor is this a story about Net Zero. We need to go much further.

The greatest response we have to the climate emergency is to make our cities Carbon Negative. But to do that, we have to make them pleasant places to live. but first we need to look at what we are working with.

“For a long time people have tried to ask “what makes a world city” and produce indices to calculate where it is best to live,” says Tribe. “Usually Vienna, Toronto, Vancouver or Melbourne seem to be in the top five. But these metrics are outdated, because ultimately those cities have a very high per capita consumption rate.”

They are beautiful places to live, but ultimately, these places are not driving a sustainable lifestyle. Be it through high consumption, low density living or limited public transport. So the measures of sustainability are not met within the ‘best cities by liveability’.

“And so we are considering now looking at different indices, which actually will measure cities of the future, more appropriately and in line with the challenges that we face around climate change and equality and diversity.”

These changes are nothing new, the approach to planning urban spaces has followed particular trends and fashions historically.

“So suburbia and new towns were de rigueur following the 1950s. Then we looked at urban renewal, which was a regeneration move. But that led us to gentrification in many places, which displaced existing communities,” says Tribe. “Now we are looking at a very integrated approach, where we have a balanced look at the economic, social and environmental angles within our designs and planning projects.”

But we are still stuck with these legacy suburbs, which Tribe calls ‘cartopias’. They have an enormous exodus in the morning as people travel to work, and an enormous return in the evening. Each incidence requiring an enormous outlay of carbon, and many hours wasted in traffic. So we need to apply some measures to existing cities, not just new developments.

There are two key figures to be aware of. By 2050 around 75-80% of the world’s population will live in cities. And by that time, it is thought that 80% of the buildings that will ever be built, will probably already exist. This is because embodied carbon is enormous, and knocking buildings down incredibly wasteful from an environmental point of view.

Existing building stock needs to be less wasteful, and people need to be in environments where public transport or active travel (biking or walking) are realistic options. Cities will not just need to be carbon negative, they will need to be significantly carbon negative.

“But the technology is emerging, you’re looking at new concretes, which are reducing their carbon content significantly, you’re seeing the rewilding of cities, which is kind of consuming and taking out greenhouse gas and carbon, you know, there are technologies emerging and all the top academic institutions that really driving the innovation into the material science particularly, and I’m seeing a huge amount of private sector investment in it as well. When economics gets involved, you know change is going to happen,” says Tribe.

“I think we can do a lot more as an industry, I think we need to really be those advocates for change and driving sustainability within our urban environments. And if we believe as an industry, that compact urban destinations are the most effective way to respond to climate change, then yes, we have to really be more vocal, and really drive the agenda around liveability, quality of life sustainability, and creating a balance with nature.”

Improving building performance

Although liveability is an individual concern, interventions to improve the sustainability credentials of a city have to be performed at scale to be affordable.

When it comes to new developments on virgin sites, the only limit is modern technology. In a truly modern apartment block, there is really no excuse for energy spent on heating. Passive developments exist today that use waste heat from a number of sources to heat rooms. But most of our cities already exist.

Rupert Green is Atkins’ Market Lead for Net Zero Energy Infrastructure, his responsibilities lie primarily in the technical requirements of projects, but like Tribe, he is drawn to this bigger picture.

“Looking at just looking at the residential buildings for a start, if you look talking about a truly sustainable city in 2050, you’re talking about a city that has removed the vast majority of fossil fuel use from within that city,” says Green. “You are talking about a city that is heavily reliant on electricity that would be the primary energy source, that would also be likely be decentralised energy, for the provision of heating and hot water for buildings.”

If London is taken as an example, which has a sophisticated and complex plan for the future, this would be contingent on being able to put the correct infrastructure in place well before 2050 to enable London to shed its dependence on fossil fuels. Decentralisation of energy generation is a key part of this.

“When you’re talking about decentralised energy, London has taken enormous steps to put in place strategies at a local authority level, at a council level, to understand where that where the opportunities are for decentralising, existing and future buildings and planned buildings. And as part of that work, the potential sources for waste heat have been identified,” says Green.

For example, redirecting waste heat from supermarket coolers, or from industrial sites to heat residential property. Today, this would be done via heat pumps and the opportunities are enormous, but would be insufficient without reducing the energy demand of the residential building stock, as well of future buildings.

“So for new build, I don’t see that as a problem. The legislation is in place. There are very clear mechanisms that that allow developers to produce buildings that are essentially passive, that require little or no space heating. So the majority of the load will be for hot water generation,” says Green. “The challenge lies with existing buildings and the ability to improve the installation and the thermal performance of those buildings sufficiently. And that is a huge, even monumental challenge.”

The standard building stock in London is the Victorian terrace. These are notoriously difficult to retrofit and insulate. They experience issues with condensation and damp, and are probably the largest challenge in London’s journey to being a carbon negative city.

In tackling this, we are looking at large-scale interventions to have even a chance of an efficient approach. This would ideally mean street by street, which in a Western democracy is difficult. People can be incentivised, but not forced to improve their building efficiency. It is not economic to do things house-by house, but street-by-street has the potential to unlock funding.

The energy-led future

In the city of the future, energy drives almost everything, not just building performance. Transportation will also be ever more linked as people switch to electric vehicles.

“You have a situation where everything is reliant on the same sorts of energy. So that does introduce issues around the capacity, which we are well aware of, especially in certain parts of London today. We are already at capacity in terms of the amount of spare electrical supply that is available. The infrastructure is at its limits and significant investment is required to create additional capacity to allow development,” says Green.

These existing capacity issues exist even before the mass adoption of electric vehicles and without significant adoption of electric heat pumps.

“The penetration of heat pumps in London is miniscule compared with what it needs to be. So we’re talking about a fundamental shift in how we view cities,” adds Green. “We will understand the issues around transport planning, and then try to encourage active transport and try to reduce reliance on private vehicles.”

But in some respects the conversation around electrical infrastructure is already going in the wrong direction. Rapid car charging ruins batteries and is not ideal for a managed, sustainable grid. It is far more beneficial to everyone for these vehicles to be charged slowly overnight when energy is less in-demand.

This can be extended into other areas, running washing machines and dryers overnight for example. And there are existing tariffs in the UK such as Economy7 that encourage this.

Peak shaving, where we avoid use of energy at peak times will be a critical part of a future sustainable community. Added to this the growth in large batteries in vehicles, and local areas can take advantage of the principles of micro-gridding.

See episode #133 ‘The Legacy of the Lac Megantic Disaster’ for more information on the possibilities of microgrids.

A modern London development

The London Plan is one of the best visions for zoning an old city out there, the 15-minute city, where all usual amenities are within a 15-minute active travel journey is another, put forward by Anne Hidalgo, former mayor of Paris.

In London today, one of the most modern developments is being undertaken by the London Legacy Development Corporation (LLDC). It is an organisation created to continue the investment from the 2012 London Olympics and effectively convert the Olympic Park sites into lasting community with modern housing.

“A lot of hard infrastructure was put in place before the Games,” says Clare Hebbes, Director of Development at LLDC. “The electricity cables were put in for example – there are lots of empty ducts so that things can be changed and made to work for later, a large sustainable drainage scheme has been really successful, and an energy network.”

From a sustainability angle, this district energy network was key and Hebbes says it has saved a lot of carbon. She adds,“It’s also presented another opportunity for lots of learning. And obviously, as the grid has decarbonised the energy network performance, has reduced in terms of carbon saving. And so we’re now doing quite a lot of work on how we can decarbonize that network moving forward. And so continue to take the benefits from what is an awful lot of infrastructure, which has already been installed. So to date that’s connecting to the energy network has been quite a key part of our sustainability story.”

On the liveability side, rather than just creating housing, the neighbourhoods were designed to have identities and to foster the growth of communities. A key part of that has been making sure the neighbourhoods link in with local communities. This can be as simple as crossing points or a larger intervention such as a bridge over a road.

A particularly unusual piece of work related to this side of the project is a study that has been done in conjunction with the Institute for Global Prosperity. This study goes beyond the usual examination of changes in employment levels and whether average salaries have increased.

Because what that doesn’t do is tell you the story of the individuals. And so this is a very long piece of work, because it’s really about tracking individuals and seeing the impact that we’ve made on individual lives, rather than just on an area,” says Hebbes, “and this is an ongoing piece of work.”

This is important because it allows the study to determine whether the people have had their prosperity improved. Earlier studies would not be able to differentiate between that and gentrification. The removal of a local community rather than improving its lot.

Going negative

As for whether cities can provide negative carbon, Hebbes agrees that they are our best chance of achieving that. But she believes that the embodied carbon needs to be thought of in conjunction with embodied energy, and the fundamental efficiency of building stock.

“Inevitably the debate is always more complicated. It’s very seldom you get a carbon win without having to balance something else. And I think that is the that’s the hardest part of this conversation. It is how do you how do you balance the different impacts of any of the solutions we have?

“And I think because it’s so hard, in some cases it just ties [decision-making] up for a really long time. And so, solutions get stalled. And if we could find a quicker way through that, I think it would help considerably.”