Thrift is a concept where you reduce, reuse and recycle,

but yet with an economic aspect I think has a real potential for change.

My grandmother, she knew about thrift.

This is her string jar.

She never bought any string.

Basically, she would collect string.

It would come from the butcher's, it would come from presents.

She would put it in the jar and then use it when it was needed.

When it was finished, whether it was tying up the roses

or a part of my bike,

once finished with that, it'd go back into the jar.

This is a perfect idea of thrift; you use what you need,

you don't actually purchase anything, so you save money.

Kids also inherently know this idea.

When you want to throw out a cardboard box,

the average kid will say, "Don't! I want to use it for a robot head

or for a canoe to paddle down a river."

They understand the value of the second life of products.

So, I think thrift is a perfect counterpoint

to the current age which we live in.

All of our current products are replaceable.

When we get that bright, new, shiny toy,

it's because, basically, we got rid of the old one.

The idea of that is, of course, it's great in the moment,

but the challenge is, as we keep doing this,

we're going to cause a problem.

That problem is that there is really no way.

When you throw something away, it typically goes into a landfill.

Now, a landfill is basically something which is not going to go away,

and it's increasing.

At the moment, we have about 1.3 billion tons of material every year

going into landfills.

By 2100, it's going to be about four billion tons.

See, instead, I'd prefer if we started thrifting.

What that means is, we consider materials when they go into products

and also when they get used,

and, at the end of their life: When can they be used again?

It's the idea of completely changing the way we think about waste,

so waste is no longer a dirty word --

we almost remove the word "waste" completely.

All we're looking to is resources.

Resource goes into a product

and then can basically go into another product.

We used to be good at thrifting.

My grandmother, again, used to use old seed packets

to paper the bathroom walls.

I think, though, there are companies out there who understand this value

and are promoting it.

And a lot of the technologies that have been developed for the smart age

can also be adapted to reduce, reuse and also thrift more proficiently.

And as a materials scientist,

what I've been tracking over the last couple of decades

is how companies are getting smart at thrifting,

how they're able to understand this concept

and profit from it.

I'm going to give you two examples.

The first one, a good one; the second one, not so good.

The first is the automotive industry.

Not always known as the most innovative or creative of industries,

but it turns out, they're really, really good at recycling their products.

Ninety-five percent of every single car that goes on the road

gets recycled here.

And of that car, about 75 percent of the entire car

actually gets used again.

That includes, of course, the old steel and aluminum

but then also the plastics from the fender and the interiors,

glass from the windows and the windshield

and also the tires.

There's a mature and successful industry that deals with these old cars

and basically recycles them and puts them back into use

as new cars or other new products.

Even as we move towards battery-powered cars,

there are companies that claim they can recycle up to 90 percent

of the 11 million tons of batteries that are going to be with us in 2020.

That, I think, is not perfect,

but it's certainly good, and it's getting better.

The industry that's not doing so well is the architecture industry.

One of the challenges with architecture has always been

when we build up, we don't think about taking down.

We don't dismantle, we don't disassemble, we demolish.

That's a challenge,

because it ends up that about a third of all landfill waste in the US

is architecture.

We need to think differently about this.

There are programs that can actually reduce some of this material.

A good example is this.

These are actually bricks that are made from old demolition waste,

which includes the glass, the rubble, the concrete.

You put up a grinder, put it all together, heat it up

and make these bricks we can basically build more buildings from.

But it's only a fraction of what we need.

My hope is that with big data and geotagging,

we can actually change that,

and be more thrifty when it comes to buildings.

If there's a building down the block which is being demolished,

are there materials there

that the new building being built here can use?

Can we use that, the ability to understand

that all the materials available in that building are still usable?

Can we then basically put them into a new building,

without actually losing any value in the process?

So now let's think about other industries.

What are other industries doing to create thrift?

Well, it turns out that there are plenty of industries

that are also thinking about their own waste

and what we can do with it.

A simple example is the waste that they basically belch out

as part of industrial processes.

Most metal smelters give off an awful lot of carbon dioxide.

Turns out, there's a company called Land Detector

that's actually working in China and also soon in South Africa,

that's able to take that waste gas --

about 700,000 tons per smelter --

and then turn it into about 400,000 tons of ethanol,

which is equivalent to basically powering 250,000, or quarter of a million, cars

for a year.

That's a very effective use of waste.

How about products more close to home?

This is a simple solution.

And it, again, takes the idea of reducing, reusing,

but then also with economic advantage.

So it's a simple process of changing from a cut and sew,

where typically between 20 and 30 materials are used

which are cut from a large cloth and then sewn together or even sometimes glued,

they changed it and said that they just knitted the shoe.

The advantage with this is not just a simplification of the process,

it's also, "I've got one material. I have zero waste,"

and then also, "I'm able to potentially recycle that at the end of its life."

Digital manufacturing is also allowing us to do this more effectively.

In this case, it's actually creating the theoretical limit of strength

for a material:

you cannot get any stronger for the amount of material

than this shape.

So it's a basic simple block,

but the idea is, I can extrapolate this, I can make it into large formats,

I can make it into buildings, bridges,

but also airplane wings and shoes.

The idea here is, I'm minimizing the amount of material.

Here's a good example from architecture.

Typically, these sorts of metal nodes are used to hold up large tent structures.

In this case, it in was in the Hague, along a shopping center.

They used 1600 of the materials on the left.

The difference is, by using the solution on the right,

they cut down the number of steps from seven to one,

because the one on the left is currently welded,

the one on the right is simply just printed.

And it was able to reduce waste to zero,

cost less money

and also, because it's made out of steel,

can be eventually recycled at the end of its life.

Nature also is very effective at thrift.

Think about it: nature has zero waste.

Everything is useful for another process.

So, in this case, nanocellulose,

which is basically one of the very fine building blocks of cellulose,

which is one of the materials that makes trees strong,

you can isolate it, and it works very much like carbon fiber.

So, take that from a tree, form it into fibers,

and then those fibers can strengthen things,

such as airplanes, buildings, cars.

The advantage of this, though, is it's not just bioderived,

comes from a renewable resource,

but also that it is transparent,

so it can be used in consumer electronics, as well as food packaging.

Not bad for something that basically comes from the backyard.

Another one from the biosource is synthetic spider silk.

Now, it's very hard to actually create spider silk naturally.

You can basically get it from spiders,

but in large numbers, they tend to kill each other, eat each other,

so you've got a problem with creating it,

in the same way you do with regular silk.

So what you can do is instead take the DNA from the spider,

and put it into various different things.

You can put it into bacteria, you can put it into yeast,

you can put it into milk.

And what you can do then is,

the milk or the bacteria produce in much larger volumes

and then from that, spin a yarn and then create a fabric or a rope.

Again, bioderived, has incredible strength -- about the same as Kevlar --

so they're using it in things like bulletproof vests and helmets

and outdoor jackets.

It has a great performance.

But again, it's bioderived, and at the end of its life,

it potentially can go back into the soil and get composted

to again be potentially used as a new material.

I'd like to leave you with one last form which is biobased,

but this, I think, is like the ultimate thrift.

Think about the poster child for conspicuous consumption.

It's the water bottle.

We have too many of them, they're basically going everywhere,

they're a problem in the ocean.

What do we do with them?

This process is able not just to recycle them,

but to recycle them infinitely.

Why is that interesting?

Because when we think about reusing and recycling,

metals, glass, things like that, can be recycled as many times as you like.

There's metal in your car

that may well have come from a 1950s Oldsmobile,

because you can recycle it infinitely with no loss of performance.

Plastics offer about once or twice of recycling,

whether it's a bottle, whether it's a chair --

whatever it is, if it's carpet --

after two times of recycling, whether it goes back into another chair, etc,

it tends to lose strength, it's no longer of any use.

This, though, just using a few enzymes, is able to recycle it infinitely.

I take a bottle or a chair or some other plastic product,

I basically put it in with a few enzymes, they break it apart,

they basically put it back into its original molecules.

And then from those molecules,

you can build another chair or carpet or bottle.

So, the cycle is infinite.

The advantage with that, of course,

is that you have potentially zero loss of material resources.

Again, the perfect idea of thrift.

So in conclusion, I just want to have you think about -- if you make anything,

if you're any part of a design firm,

if you basically are refurbishing your house --

any aspect where you make something,

think about how that product could potentially be used

as a second life, or third life or fourth life.

Design in the ability for it to be taken apart.

That, to me, is the ultimate thrift,

and I think that's basically what my grandmother would love.

(Applause)