Good morning, happy to see many of you again and I look forward to seeing some of you even further this afternoon.
You’ve had to restructure things, like these proteins restructure themselves according to needs
and so we are going to speak about, and show you something about solar energy mostly.
And I’ll make very few introductory remarks.
Solar energy is of course an enormous boom to us, there’s a huge amount of energy coming down,
many orders of magnitude more than we humans need or claim to need.
And so the role of science is obvious, the role of science is to find ways
in putting this super abundance of energy to good use in an energy hungry world.
There are 2 broad forms of energy, both of which are derived from the sun.
Namely solar and wind energy.
And many of us believe that mankind’s dependence on fossils which is coming to an end,
the so called peak oil moment in history when oil production reaches its peak and begins to decline,
everybody is watching for that like for a comet in the sky, when will that come.
And there of course is no clear prediction but some things can be said with, well as Professor Kroto said,
with whatever near certainty, it’s going to happen before the middle of the century which is practically now.
My own study of the data leads me to 2 different results, one of which is related to population that I’ve already mentioned
and that is peak oil, the top of the production of oil followed by a very rapid decline in a few decades
and the other one is peak oil per person and that’s a different time.
Now my estimates based on other people’s work say that peak oil per person should come around in around 7 years.
That’s a major and immediate problem.
My government, I’m an American, for many years just denied the existence of this problem,
I mean very dramatically President Bush a few weeks after coming into office,
pulled out of the Kyoto agreement and that was a very dramatic and many of us felt very unfortunate step.
We are now in a much better situation but at that time, it’s a long story and we can talk about that this afternoon,
I began to become a film maker.
And I felt the government is not going to take the initiative, or my government will not take the initiative,
so let’s try and build a fire under them by popular pressure.
And this film that I’m going to show you now and we can do some more, show you some more things this afternoon,
came about this way.
And I’m ready to go so can I.
(start of film).
Until about 200 years ago we humans largely depended for our energy needs on our own muscles, on animals and on burning wood.
When we ran short of wood we discovered a marvellous source of energy stored in fossil fuels.
Coal, gas and oil.
Fossil fuels are nothing more than the transformed remains of plants and animals that died millions of years ago.
When we burn them we release the energy of the ancient sun light that helped create them in the first place.
But we have come to be dangerously dependent on fossil fuels, even addicted to them.
Not only does that accelerate global warming, we’re likely to run out of cheap oil and gas by mid century.
Coal though much more abundant is highly toxic.
So we must do something urgently.
In the developed world we must learn to use less energy, a 50% reduction may be necessary.
And we must turn increasingly to renewable energy sources.
One of our most promising solutions may be to turn back to our old friend the sun.
Do you know that the solar energy that strikes the earth surface for one hour
is enough to feed the world’s current electricity needs for one year?
So why haven’t we gone solar already, I mean it’s pollution free, there’s no global warming,
there’s no dependence on foreign oil powers, it’s decentralised so it’s virtually terrorist proof
and effectively there’s an infinite supply.
I mean it sounds like the dream solution doesn’t it.
But will it work?
This film is all about sun light, what it is, how we are learning to use it and what the future may hold.
Our story starts however long ago and far away.
Many ancient peoples worshiped the sun, the Egyptian Pharaoh Akhenaton founded the first religion in history
to have a single god and that god was the sun.
The writers of the bible acknowledged its primacy by having god’s first instruction be ‘let there be light’.
But what exactly was this stuff light?
No one had any clear idea until the eminent English scientist Isaac Newton took an educated guess about 300 years ago
and wrote 'are not the rays of light very small bodies emitted from shining substances’.
(Walter Kohn) Well, Newton’s idea of light was really quite simple one, he found that light consisted of a stream of particles
that as he knew travelled in straight lines.
Newton’s guess was a good one as Einstein would later show.
But a very different guess was made by a Dutch man Christiaan Huygens,
Huygens observed the waves made by a stone dropped in water, he had a brilliant insight,
suggesting that light as he said spreads by spherical surfaces and waves.
Here’s a drawing that Huygens made to illustrate waves of light flowing from a candle.
Huygens had created the wave theory of light but like Newton he couldn’t back up his theory with experimental results.
And so things stood until 1803 when a Londoner called Thomas Young was invited
to make a presentation on light in the famous lecture theatre at the Royal Institution.
(Alan Heeger) The Royal Institution was founded in 1799, immediately a big hit,
people came to be educated, to see, to learn about science,
it was almost evidently like a magic show.
These physics students at Stanford University are replicating one of Thomas Young’s experiments.
Light from a single source must enter 2 narrow slits and eventually hit a screen some distance away.
The reason that Young did this experiment was to try to see if light was a wave or a particle.
Was Newton right or Huygens?
The light from each slit spreads out like waves of water,
each wave interferes with the others creating a pattern of light and dark patches.
(Walter Kohn) All across that second screen its intensity varied across the screen in a very regular way.
And that could be perfectly naturally explained by the wave theory and couldn’t be explained at all by Newton’s theory.
So Christiaan Huygens theory was right, light is a wave.
But that’s not the end of the story.
In the early 19th century no one thought there was much connection between light, electricity and magnetism,
they seemed like 3 very different phenomena.
Then here at the Royal Institution a young scientist called Michael Faraday started doing experiments
with an electro magnet and he discovered that electricity and magnetism were 2 sides of the same coin.
Another British scientist, James Clark Maxwell then set out to formulate Faraday’s findings mathematically.
And his equations predicted the existence of electro magnetic waves.
(Walter Kohn) So Maxwell discovered electro magnetic waves, mathematically.
He calculated the speed of these waves and he noticed that it was exactly the same
as the speed of light that had previously been measured.
So suddenly he finds himself confronted with the fact that light is a wave phenomenon
and it is an electro magnetic wave phenomena.
One of the great insights of natural science.
German scientist Heinrich Hertz experimented by shining lights on electrical circuits
and results seem to confirm Maxwell’s theory.
Our knowledge is complete said Hertz, a refutation of these views is unthinkable, the wave theory of light is a certainty.
However Hertz assistant, Philip Lenard decided to look more closely at one of the experiments
where there was a gap in the electrical circuit.
(Nick Leindecker) Right now there’s no high voltage so you don’t see anything happening,
let’s go ahead and fire up the high voltage.
Lenard found that if you shown light at low frequencies, red, green or blue, on these 2 metal balls,
nothing happened but if the light was above a certain frequency, into the ultra violet,
electrons escaped from the metal and jumped across the gap, completing the circuit and creating a spark.
Now that didn’t sound like the action of a wave.
(Nick Leindecker) Now this doesn’t make any sense,
a threshold, a sudden change going from violet to ultra violet if light is a wave,
smooth and continuous in how it delivers its energy.
But if light is a particle, a threshold makes a lot more sense.
(Walter Kohn) Here was an incredible paradox because so many experiments could apparently only be explained by the wave theory
but here there was this new class of experiment that could very easily be explained by a particle theory
but not by the wave theory, what to do with this.
No one could have predicted the problem would be solved by a patent office clerk in Switzerland
but that’s what Albert Einstein was when he came up with the answer.
In 1905 Einstein had the revolutionary insight that light had a dual nature.
In some context as Maxwell and Hertz had shown it was a wave,
but in others as in Lenard’s measurements it consisted of discrete quanta of energy or photons.
The higher the frequency the greater their energy.
Amazingly Newton and Huygens had both been correct.
An experiment using modern equipment at Stanford shows very clearly that Einstein was right.
(Ross Dunkel) What we want to do is we want to observe single photons,
so what we have here is we have a very sensitive photo detector
and its connected to these optics through this fibre optic cable which basically just funnels light into the detector.
So we actually need to cover up these optics and we need to actually shut the room lights off
and I’ll use this flash light as a light source to get photons into the detector.
In darkness you hear no evidence of photons striking the detector,
as the light becomes stronger you hear a growing rush of photons,
when the light is dimmed there are fewer and fewer photons reaching the detector until you begin to hear the photons one by one.
(Ross Dunkel) So this shows that Einstein was right and light is indeed made up of particles.
But nobody else could understand how light could be both a wave and a particle, not even the famous physicist Max Planck.
(Walter Kohn) We know today the letter that Max Planck wrote to recommend Einstein
and in this letter he says many complementary things about Einstein and then he comes to Einstein’s theory of a photon
and he says you should forgive Einstein, even a very great man can make a big mistake occasionally.
And of course eventually Einstein got his Nobel Prize for that work.
It wasn’t relatively that won him his Nobel Prize, it was what he called the photo electric effect.
(Dr. Zhixun Shen) The photo electric effect is really the stroke of genius, it took courage, of course it also took insight
and this genius touch, as I emphasise again, that transcends the simple analysis and the major logic
and that is what is truly great about this great mind.
The entire history and development of modern work on solar electricity
depends on Einstein’s understanding of this photo electric effect.
In this context light consists of lots of individual packets of energy, ready to react with what ever they strike.
Einstein’s insight had set the stage for the future advent of solar power.
In the mid 20th century some of the greatest developments in applied technology were made at Bell Labs,
the Bell telephone laboratories in New Jersey.
Here in 1947 William Shockley, John Bardeen and others developed the transistor,
the most important electronic discovery of the century.
It was both a switch and an amplifier and it transformed everything from telephones to computing.
(Walter Kohn) It revolutionised everything.
You can really speak of the world before the transistor and the world after the transistor.
Doctor Walter Kohn worked here as a young man in the 1950’s.
(Walter Kohn) The first time I came to Bell labs it felt like a very intimidating place,
it was known to everybody in physics as the number one laboratory in the world.
My recollection is that there were approximately 3,000 people working there, you know everybody was doing his thing
but everybody was connected to other people who were doing their things.
It was this connection that brought together the work of 3 scientists to create the world’s first practical solar cell.
(Here are the inventors of the Bell solar battery)
Daryl Chapin was an electrical engineer,
he’d been experimenting with early selenium cells for powering telephone lines in remote areas.
A physicist Gerald Pearson was trying to develop a rectifier to replace mechanical telephone switching devices
and a chemist, Calvin Fuller was working with the semi conductor silicon as part of the transistor project.
Bell scientists liked silicon because of its electronic characteristics and because it was abundant,
it’s basically sand and makes up more than ¼ of the earths surface.
A single atom of silicone has 4 active electrons which are called valence electrons.
In a crystallise silicon each of these valence electrons,
together with a valence electron of a neighbouring silicon atom forms a bond adjoining those 2 atoms.
However perfect it looks solid silicon like all semi conductors doesn’t work electronically
unless a small fraction of the silicon atoms are replaced by foreign atoms called impurities.
(Walter Kohn) Pure silicon is one of the dullest substances you could imagine, does very little of interest,
you introduce these miniscule fractions of impurities, I say miniscule part in a million,
part in a billion atoms, suddenly all kinds of exciting things can be made to happen.
The chemist Kelvin Fuller developed a highly controlled process for diffusing impurities into silicon,
I’m interrupting here quickly, we are short of time, partly because we’ve run late, there have been problems here
and partly because the film runs a little longer than the time that was assigned to me.
So what we have decided to do in discussion is we will show you a few more sections of this film,
so please excuse the abruptness of the transition and we will show some more depending on interest this afternoon
when the students will meet with me as has been the case the last few days.
Ok so can I see the list of chapters.
(resuming film).
But will it become a major part of the world’s energy mix.
That depends on people like Terry Jester, she’s worked in photovoltaic’s since the 1970’s
(Terry Jester) It was just an amazing time to be part of that group of people working 80/90 hour weeks,
feeling so committed and feeling like what we were doing and what we could do would change the world and change the future.
Terry Jester is director of operations at this factory which is now owned by Shell.
It has been making solar panels for more than 25 years.
The whole time the primary target has been to cut costs,
to increase the efficiency of the solar panels or to make them in a cheaper way.
Shell is one of the oil companies that appear to take solar power seriously.
They recently unveiled a large installation to power water pumps near Bakersfield California.
(Hans Willemsen) This installation here of the semi tropic water district organisation is a 1 megawatt system.
The reliability of this product is one major technical reason to do something like this.
As you can hear you don’t hear anything, there’s no moving parts.
In terms of environment, apart from no noise, it is also not polluting, it doesn’t need any fuel
and the fuel is currently coming from above.
California and some other states have offered subsidies to business and home owners to encourage the development of the industry.
But it was in Japan that this idea really took off.
In some ways Japan is an extremely traditional society, it treasures beauty in everything it creates.
This has been home to the same family for over 200 years, they still serve tea in the time honoured way
but Japan has other tastes too.
Spend a few minutes in down town Tokyo or Osaka and you’ll realise how deep is the Japanese love affair
with technology and how much energy is required by this industrial super power.
(Takashi Tomita) In Japan we have very few natural energy resources.
It is very important, we don’t have so many coals, petroleum, natural gasses and other, uranium etc,
therefore we should create the energy by ourselves.
(Ron Kenedi) Because of Japan’s needs for electrical independence and power independence
they had a large will to invest in solar power.
Sharp started researching in solar cell technology in 1959, and were the first to produce a solar cell in Japan.
In 1961, Sharp became the first to apply solar technology to a consumer product by producing the solar powered radio.
As with cars, Japanese companies came from nowhere and soon became world class in electronics.
Subsidies drove the market.
This traditional Japanese house is now powered by solar panels.
For our children’s generation to keep a clean environment is very important.
This year Kyoto protocol will become effective, so from now on this becomes a more important issue.
Our dream is to install solar systems for all Japanese houses.
All across Japan modern apartment blocks and factories are sprouting solar panels.
The secret of success in Japan was wholehearted government encouragement and subsidy.
(Ron Kenedi) A real change happened in 1994 where the Japanese government decided
that they wanted to stimulate the growth of solar power in Japan
to actually be an important part of the electrical distribution in the country.
But because the price of all electricity in Japan is so high, solar power is now almost competitive on price alone.
(Professor Martin Green) At the first stage the Japanese government pays a subsidy of 5% for the solar system
as opposed to the 75% originally
but the number of people wanting to buy the systems continues to increase.
So the systems are very close to being economic now.
(Richard Swanson) This market today is driven really by 2 countries, Germany and Japan
and they’ve both taken a truly leading visionary role in driving the technology, in supporting the technology.
Both countries have tremendous political support for clean energy.
And to me it’s a little bit ironic in that we could be looking in the future at importing solar panels,
just as we import oil today because as a result of the markets being both in Germany and Japan,
the industry, the centres of excellence have generally gravitated towards those 2 countries.
The Germans have embraced solar power as enthusiastically as the Japanese.
What's called the world’s largest solar installation was dedicated in June 2005 at Mühlhausen in Bavaria.
It spreads over several acres and provides up to 10 megawatts of power for the electricity grid...
(end of film).
So you notice there was a little pow wow here and my time is up
but I wanted to tell you a very important section is coming right after this,
it’s about solar energy in the developing world and we’ll start at that point this afternoon,
for those who would like to come over and see it there.
And we’ll hopefully make arrangements for people to be comfortable and maybe even sit on chairs.
In any case to close for the moment I’ve been very optimistic,
become very optimistic about the real possibility of a kind of,
after a certainly somewhat turbulent transition from fossil fuels to renewable fuels,
that the world can manage on solar and wind energy alone.
I’m not saying it should do that but I would not be at all surprised
if those would be the 2 principle sources of energy after the transition away from fossil fuels.
This is not totally a fantasy, if you look at the fraction of total energy now produced by sun
and wind you would say this is an absolute madness of Walter Kohn.
But if you look a little more closely you’ll see that over the last 5 years,
every year solar energy and wind energy similarly has grown by about 30%.
Now everybody here has had experience with exponential functions and 30%, even if you start with a tiny amount,
now if you take solar and wind together, it’s something like a few percent of the world’s energy.
But already in 10 years it will have grown by a factor of perhaps 5 or 6.
In 20 years by a factor of 25 and in 30 years, this is exponential growth, by a factor of over 100.
There are no physical limitations to this growth, I mean there’s enough, plenty of area, I mentioned to you,
I think somebody else mentioned that earlier, perhaps Professor Kroto,
the amount of sunlight falling on the earth is thousands of times more than we need for electricity production.
Even wind which has more limitations because of the structural demands on large turbines,
even wind in principle can produce more than the entire energy needed by the world.
Together in practice and if you look at the record, recent record, I believe that this is a possibility.
Do not misunderstand me, I’m not here contradicting Professor Molina’s thesis
which he accredited to a couple of people in Princeton, the so-called wedge picture,
it’s not really a theory, it’s just if you have several sources of energy you add the energies.
But we wanted to be very concrete and just look at what seems to us the most probable main sources of energy in the future
and we were surprised and pleased by these results.
So now it’s up to us and especially up to you to really do it.
Thank you very much.