Vishaan Chakrabarti: A vision of sustainable housing for all of humanity | TED Countdown

Summary

The speaker, an architect, discusses the looming population boom and the need for sustainable housing solutions. They propose a 'Goldilocks' scale of two- to three-story buildings as an ideal balance between housing density and renewable energy potential. These structures, made from local materials, could be equipped with solar panels and battery systems for energy efficiency, promoting walkable, equitable communities that reduce carbon footprint and support mass transit.

Takeaways

• 🌍 By 2100, the world's population is expected to reach almost 11 billion, which is 3 billion more than today.
• 🏗️ To accommodate this growth, approximately 2.4 trillion square feet of new built space is needed, equivalent to adding a New York City every month for the next 40 years.
• 🌳 The speaker, an architect, suggests that new housing could potentially be carbon-negative, offsetting more carbon than it produces.
• 🏙️ Existing cities are looking towards clean energy grids for hope, but the transition is slow due to issues like transmission lines and nuclear energy politics.
• 🏡 Net-zero single-family homes are feasible with current technology, especially in sunny climates, but they can be expensive and lead to sprawl.
• 🌿 The speaker advocates for 'Goldilocks' scale housing — two to three-story buildings — as a sustainable and beautiful solution that balances the need for housing and roof area for solar panels.
• 🔋 This housing can be constructed with local materials like wood or brick, have solar panels, and incorporate state-of-the-art battery systems for energy storage.
• 🌡️ It can also feature advanced heating and cooling systems that use thermal storage to manage energy use more efficiently.
• 🚌 If implemented, this housing model could support mass transit, create dense but green neighborhoods, and reduce the need for car-oriented sprawl.
• 🌱 The 'Goldilocks' framework could compost waste, provide affordable housing, and integrate socially and racially diverse communities.
• 🌟 If globally adopted, this model could house all 11 billion people using a landmass equivalent to the size of France, leaving most of the planet for nature and agriculture.

Q & A

What is the projected world population by 2100 according to the United Nations?

The United Nations projects that the world population will reach almost 11 billion people by 2100.

How much additional space is needed to house the projected population growth?

To house the additional population, about 2.4 trillion square feet of new built space is needed, equivalent to adding a New York City every month for the next 40 years.

What is the concept of 'carbon-negative' housing?

Carbon-negative housing refers to structures that offset or sequester more carbon than they produce.

Why is it challenging to build carbon-negative towers at the moment?

Building carbon-negative towers is challenging because they are energy-intensive to construct and operate, have limited roof area for solar power, and are often made from materials with high embodied energy like steel and concrete.

What is 'mass-timber construction' and how does it relate to sustainable building?

Mass-timber construction is a technology that allows for the building of tall towers using environmentally friendly and fire-retardant wood that acts as a carbon sink. However, it is not yet widely adopted.

What is the 'Goldilocks' scale of housing mentioned in the script?

The 'Goldilocks' scale refers to two- to three-story housing that sits between single-family homes and skyscrapers, offering a balance between the number of people it can house and the amount of roof area needed for solar power.

Why are the current suburban townhomes considered unsustainable?

Current suburban townhomes are considered unsustainable because they are often cheaply built, not walkable, and do not support mass transit, leading to car-oriented sprawl and environmental degradation.

How can the 'Goldilocks' framework contribute to solving the housing problem while being environmentally friendly?

The 'Goldilocks' framework can provide affordable, communal, and equitable housing that is built with low embodied energy materials, can support solar panels, and is dense enough to support mass transit, thus being both climate-friendly and socially beneficial.

What are the potential benefits of implementing the 'Goldilocks' framework in cities?

Implementing the 'Goldilocks' framework in cities can lead to carbon-negative, transit-rich, and dense housing that supports mass transit, reduces the need for cars, and leaves room for green spaces, thus improving urban sustainability.

How does the speaker envision the deployment of the 'Goldilocks' framework in different cities like New York and Calcutta?

The speaker envisions deploying the 'Goldilocks' framework in a way that adapts to local materials and cultural expressions, resulting in carbon-negative, transit-rich, and joyful places to live in both New York and Calcutta.

What is the significance of the statement that if all 11 billion people lived at the 'Goldilocks' scale, it would use up a landmass equivalent to the size of France?

This statement highlights the efficiency and sustainability of the 'Goldilocks' scale, showing that it's possible to house the entire projected global population while using a relatively small land area, leaving the majority of the planet for nature and agriculture.

Outlines

00:00

🌍 Population Growth and Housing Challenges

The speaker begins by sharing their Indian heritage and large family, leading into a discussion about the United Nations' prediction of a world population reaching almost 11 billion by 2100. This would require constructing an immense amount of new housing space, equivalent to adding a New York City-sized area every month for the next 40 years. Despite being an architect, the speaker finds this prospect daunting. They address the concern of housing additional billions amidst climate change and propose the idea of carbon-negative housing. The speaker discusses the limitations of clean energy grids in existing cities and the impracticality of net-zero single-family homes and skyscrapers due to their high costs and environmental impacts. They introduce the concept of 'Goldilocks' scale housing as a potential solution.

05:00

🏡 The Goldilocks Framework for Sustainable Housing

The speaker describes the 'Goldilocks' scale of housing, which is two to three-story buildings that are familiar in many beloved cityscapes. They critique the current trend of building unsustainable, non-walkable suburban townhomes at this scale. The 'Goldilocks' framework is presented as a solution that balances the number of people it can house with the necessary roof area for solar panels. This type of housing can be constructed from local materials with low embodied energy and could incorporate state-of-the-art battery systems, efficient heating and cooling systems, and waste composting. The speaker emphasizes the potential for this model to provide affordable, communal, and equitable housing that can be tailored to different communities. They also highlight the environmental benefits, such as reduced stormwater impacts and heat island effects, and the potential to leave more land for nature and agriculture.

10:04

🌱 Vision for a Sustainable Future

In the final paragraph, the speaker conveys optimism, asserting that the world does not lack the land or technology to house an additional three billion people; what is needed is vision. They reiterate that the 'Goldilocks' framework could potentially house all 11 billion people using a landmass the size of France, allowing the majority of the planet to remain undeveloped for nature and agriculture. The speaker concludes by emphasizing that this model could offset a significant amount of carbon, even more than all the cars in the world, and calls for action based on the readily available solutions.

Keywords

💡Population Growth

Population growth refers to the increase in the number of people living on Earth over a certain period. In the context of the video, it is highlighted as a significant challenge for housing and sustainability by 2100, with the United Nations predicting a population of almost 11 billion people. This growth necessitates building new housing space equivalent to adding a New York City every month for the next 40 years.

💡Net-Zero Housing

Net-zero housing implies buildings that produce as much energy as they consume over the course of a year, resulting in zero net energy usage. The video discusses the potential of net-zero single-family homes, particularly in sunny climates, to combat climate change. However, it also points out the challenges of high costs and sprawl.

💡Carbon-Negative Housing

Carbon-negative housing is a concept where housing not only neutralizes its carbon footprint but also removes more carbon from the atmosphere than it emits. The video explores this idea, suggesting that new housing could offset or sequester more carbon than it produces, thus being part of the climate solution.

💡Clean Energy Grids

Clean energy grids are power networks that are fueled by renewable energy sources like solar, wind, nuclear, and geothermal. The video mentions clean energy grids as a hopeful solution for existing cities but acknowledges that the transition to fully clean grids is still a work in progress due to various challenges.

💡Embodied Energy

Embodied energy is the total energy required to extract, process, manufacture, transport, and install materials in a product. The video points out that most skyscrapers, which are often built from steel and concrete, have a high degree of embodied energy, making them less sustainable in terms of the energy consumed in their construction.

💡Mass-Timber Construction

Mass-timber construction is a building technique that uses large panels of wood, such as cross-laminated timber, as the primary material. The video suggests that this technology could allow for the construction of tall, environmentally friendly buildings that act as carbon sinks, though it is not yet widely adopted.

💡Goldilocks Scale

The 'Goldilocks Scale' is a term used in the video to describe a middle ground or optimal scale for housing that is neither too large (like skyscrapers) nor too small (like single-family homes). It refers to two- to three-story buildings that can provide sustainable, walkable, and community-oriented housing solutions.

💡Thermal Storage

Thermal storage is a technology that stores heat or cold for later use, typically using materials that can retain thermal energy. In the video, it is mentioned as a feature of the proposed housing model, where it can produce ice or hot water off-peak for use during peak demand, thus increasing energy efficiency.

💡Sprawl

Sprawl refers to the uncontrolled expansion of urban areas into rural and semi-rural areas, leading to low-density, car-dependent development. The video criticizes sprawl for its negative environmental impacts, such as loss of wetlands, forests, and farmland, and suggests that the proposed 'Goldilocks' housing model could be an alternative to sprawl.

💡Sustainable Urban Development

Sustainable urban development involves creating cities that are environmentally, socially, and economically sustainable. The video argues for a 'Goldilocks' framework of housing that is sustainable, supports mass transit, and is integrated into existing communities, as a model for sustainable urban development.

💡State-of-the-Art Battery Systems

State-of-the-art battery systems refer to the latest technology in energy storage, which can efficiently store electricity for later use. The video suggests that such systems could be used to supplement solar panels on the proposed housing, leveling out supply and demand for energy.

Highlights

By 2100, the world's population is expected to reach almost 11 billion, which is three billion more than today.

To accommodate this growth, approximately 2.4 trillion square feet of new built space will be needed, equivalent to adding a New York City every month for the next 40 years.

The speaker, an architect, questions how the world can house an additional three billion people without exacerbating climate change.

Net-zero single-family homes are possible with current technology, especially in sunny climates where solar panels are effective.

However, single-family homes are expensive to build and can induce car-oriented sprawl, leading to environmental degradation.

Skyscrapers, despite housing many people, have limited roof area for solar power and are energy-intensive to build and operate.

Mass-timber construction offers a sustainable alternative for building tall towers, but it is not yet widely adopted.

The speaker proposes a 'Goldilocks' scale of two- to three-story housing as a sustainable solution for urban growth.

This housing scale can be built with local materials like wood or brick, which have low embodied energy.

Rooftop solar panels and state-of-the-art battery systems can provide power, while electric air conditioning and heating systems can create thermal storage.

The housing could also compost food scraps and solid waste, turning it into usable soil or animal feed.

This framework supports affordable, communal, and equitable housing for communities in need.

The 'Goldilocks' framework is adaptable to different communities, promoting social and racial integration.

When integrated into cities, this housing supports mass transit and is dense enough to reduce the need for cars.

The housing is compact enough to leave room for trees and ground cover, reducing stormwater impacts and the heat island effect.

This model of housing has the potential to offset more carbon than all the cars in the world, making it carbon-negative.

If all 11 billion people lived at this scale, it would only require a landmass equivalent to the size of France.

The speaker concludes that we have the technology and land to house everyone sustainably; what is lacking is vision.

Transcripts

So, I was born in India.

This is just a small part of my big, beautiful family there.

I have, actually, 50, five zero, first cousins.

Most of us have a couple of kids.

And so all of this leads me to believe the United Nations

when they tell us that by 2100,

the world will have a population of almost 11 billion people.

That is, three billion more people than the planet houses today.

To house all of those people,

we need to build about 2.4 trillion square feet

of new built space.

Now to give you a sense of scale,

that is the equivalent of adding to the planet a New York City,

every month ...

for the next 40 years.

Now I'm a New Yorker and an architect,

but this scares even me.

But this is not a scary talk, I promise you.

(Laughter)

I think I know what you're probably thinking,

which is, "We are already experiencing

severe impacts from climate change.

How can the world house another three billion people?

And how can their housing needs be part of the solution,

rather than part of the problem?"

Could new housing be carbon-negative?

Meaning that it offsets or sequesters more carbon than it produces.

Now, for our big, existing cities,

there is a lot of hope in clean energy grids

fueled by renewables like solar, wind, nuclear and geothermal.

But the fact is, we are still a ways away

from getting fully clean power grids in our existing cities,

where most of this population growth is going to occur.

And that's true because of the problems

with everything from transmission lines to the politics of nuclear energy.

So, clean grids are a really important part of the solution,

but they don't help us that much, right at this moment.

What we can do today,

what we have existing technology for,

is to build net-zero single-family homes.

In sunny climates in particular, solar panels work very, very well,

because it's a lot of roof area, relative to very few occupants.

But these things, they're hardly a panacea --

in part because they're very expensive to build,

but more problematically,

because they induce car-oriented sprawl.

And I don't care if the cars are electric or autonomous --

sprawl is sprawl,

and it leads to a loss of wetlands,

a loss of forests,

a loss of farms and a loss of community.

So maybe you're thinking the right answer to house our coming building boom

are towers.

And look, I've actually been called "Professor Skyscraper."

I love a great tower.

But the reality is we are very far away from developing carbon-negative towers.

And the reason is,

towers are energy-intensive to build and operate.

They house a lot of people, which is great,

but they have very little roof area to effectively use solar,

and similarly, like, wind turbines at the top --

all of that stuff barely makes a dent.

On top of that, most skyscrapers are built out of steel and concrete,

which have a very high degree of embodied energy.

Now, I hold out a lot of hope

for a technology known as "mass-timber construction,"

which would allow us to build tall towers

out of environmentally friendly and fire-retardant wood

that's actually a carbon sink,

but we are a ways away from widespread adoption of that technology.

I also hold out hope for the idea that windows could harness solar power,

but the idea that we have effective and affordable solar glass

in the near future,

that’s even more nascent than mass timber.

So for towers to really be sustainable,

we need those clean energy grids that we spoke about,

but we don't have them available to us today.

So we have a paradox.

How do we house all of these people,

how do we build urban carbon-negative housing

in a means that's technologically attainable and broadly affordable --

and do that today?

Because I'm tired of talking about 2050.

(Cheers and applause)

I believe that the answer is hiding in plain sight,

that there is what I call a “Goldilocks” scale

that sits between the scale of housing and towers:

two- to three-story housing

that should actually look very familiar to most of you,

because we built the most beloved parts of our cities with it.

The row houses of Boston,

the hutong districts of Beijing,

most of the fabric of Edinburgh.

What we now build in this scale are largely cheap suburban townhomes.

They're banal, they're not sustainable, they're not walkable,

they're certainly not beautiful.

But could they provide a hint of a framework

for a human-scale way of solving this problem

that is great for both the climate and our societies.

This Goldilocks framework hits the sweet spot

between the number of people it can house

and the amount of roof area we need

to provide them and their communities [with] power.

It can be built out of simple local materials, like wood or brick,

both of which have relatively low embodied energy

and could be built by local workers.

And the solar panels up above could be supplemented

with state-of-the-art battery systems

that level out solar supply and user demand.

Similarly, we can have electric, state-of-the-art air conditioning

and heating systems --

this exists today.

They can create thermal storage.

What that means is it can produce ice or hot water off-peak,

for use on-peak.

This housing could compost food scraps and solid waste,

and turn it into usable soils or protein for animal feed.

And I think, most importantly,

this kind of housing could provide affordable, communal, equitable housing

for communities in dire need of it.

And I work with a lot of these communities,

and I know how much demand there is for this out there.

Speaking of communities ...

I want to emphasize that this is not a one-size-fits-all solution.

This is a framework. It's a template.

We can work with communities

to make this housing appealing, visually and socially,

make it socially and racially mixed,

integrated into the lives of existing communities.

And when it's built into our cities,

what it means is that it's dense enough to support mass transit,

like light-rail, express busses, bikes.

There are networks that plug into jobs, schools, parks

and other daily destinations in our cities.

This housing is compact enough

that it leaves room for lots of trees and ground cover.

That means that we can lower stormwater impacts;

we can reduce the heat island effect;

we can lower the demand for air conditioning.

And for every family that lives in an apartment like this,

it's one less house destroying farms and forests.

Our collaborating engineers at Thornton Tomasetti have assured us that this is

the lowest-carbon-footprint-per-person means of habitation,

while also providing a sustainable use of land on our planet.

I want you to imagine with me that we deployed this Goldilocks framework

in two places that I love dearly,

New York and Calcutta.

Very different places,

but they have these big, booming downtowns,

but they also have these growing outskirts

that experience a lot of sprawl.

So they have sites like this that are near mass transit.

But imagine if, on these sites, instead of building sprawl,

we built this Goldilocks framework.

Now, that would manifest in two very, very different ways.

Different materials, different cultural expressions.

But it would give us carbon-negative, transit-rich, joyous places

for people to live and raise their families.

Now, you may be thinking,

"So this is his big idea?

Small-scale housing,

solar panels above, light-rail below,

known technologies throughout,

all organized into these affordable green neighborhoods?"

Even if you believed me that this was carbon-negative,

how many of our 11 billion people could this possibly house?

It's such a modest model.

Well, it turns out, if all of us lived at this scale,

all 11 billion of us would use up

a landmass equivalent to the size of France.

Now, I have a feeling that the French don't want us all invading their country.

(Laughter)

But I make this point to make a larger point,

which is, we can all live in this transit-rich,

carbon-negative, affordable way,

and leave the vast majority of the planet for nature,

for agriculture, for clean oceans.

We can do this.

We know that residential energy use is so voracious

that this model offsets so much carbon,

it actually more than offsets all of the cars in the world.

The impact of this would be staggering.

So yes, we can go to 11 --

11 billion people.

We don’t need to fear our neighbors.

We don’t have a lack of land or technology.

We just have a lack of vision,

because the answers are hiding in plain sight.

Thank you very much.

(Cheers and applause)