How I harnessed the wind

At age 14, in poverty and famine, a Malawian boy built a windmill to power his family's home. Now at 22, William Kamkwamba, who speaks at TED, here, for the second time, shares in his own words the moving tale of invention that changed his life.

Thank you.

Two years ago, I stood on the TED stage in Arusha, Tanzania.

I spoke very briefly about one of my proudest creations.

It was a simple machine that changed my life.

Before that time,

I had never been away from my home

in Malawi.

I had never used a computer.

I had never seen an Internet.

On the stage that day, I was so nervous.

My English lost,

I wanted to vomit.

(Laughter)

I had never been surrounded by so many azungu,

white people.

(Laughter)

There was a story I wouldn't tell you then.

But well, I'm feeling good right now.

I would like to share that story today.

We have seven children in my family.

All sisters, excepting me.

This is me with my dad when I was a little boy.

Before I discovered the wonders of science,

I was just a simple farmer

in a country of poor farmers.

Like everyone else, we grew maize.

One year our fortune turned very bad.

In 2001 we experienced an awful famine.

Within five months all Malawians began to starve to death.

My family ate one meal per day, at night.

Only three swallows of nsima for each one of us.

The food passes through our bodies.

We drop down to nothing.

In Malawi, the secondary school,

you have to pay school fees.

Because of the hunger, I was forced to drop out of school.

I looked at my father

and looked at those dry fields.

It was the future I couldn't accept.

I felt very happy to be at the secondary school,

so I was determined to do anything possible

to receive education.

So I went to a library.

I read books, science books, especially physics.

I couldn't read English that well.

I used diagrams and pictures

to learn the words around them.

Another book put that knowledge in my hands.

It said a windmill could pump water and generate electricity.

Pump water meant irrigation,

a defense against hunger,

which we were experiencing by that time.

So I decided I would build one windmill for myself.

But I didn't have materials to use,

so I went to a scrap yard

where I found my materials.

Many people, including my mother,

said I was crazy.

(Laughter)

I found a tractor fan,

shock absorber, PVC pipes.

Using a bicycle frame

and an old bicycle dynamo,

I built my machine.

It was one light at first.

And then four lights,

with switches, and even a circuit breaker,

modeled after an electric bell.

Another machine pumps water

for irrigation.

Queues of people start lining up at my house

(Laughter)

to charge their mobile phone.

(Applause)

I could not get rid of them.

(Laughter)

And the reporters came too,

which lead to bloggers

and which lead to a call from something called TED.

I had never seen an airplane before.

I had never slept in a hotel.

So, on stage that day in Arusha,

my English lost,

I said something like,

"I tried. And I made it."

So I would like to say something

to all the people out there like me

to the Africans, and the poor

who are struggling with your dreams.

God bless.

Maybe one day you will watch this on the Internet.

I say to you, trust yourself and believe.

Whatever happens, don't give up.

Thank you.

(Applause)