|Denis Hayes - Basel - 30 July 1998
Human beings have long had major impacts on their local
environments. The Mesopotamian agricultural revolution
converted the Fertile Crescent – the cradle of civilization
– into the desert wastes of Iraq. We have long flooded
river valleys and converted forests into cropland.
What is different at the dawn of the new millennium is
that we now have the power to reshape not just regions
or countries but the entire planet.
We are changing the global climate. We have drilled two
holes through the ozone layer. Human activities have
triggered a catastrophic epidemic of extinctions –
conservatively estimated at 25,000 species per year.
The human population has expanded beyond the world's
carrying capacity. And we have built an arsenal of
powerful bombs capable of causing more destruction
than an asteroid collision.
In short, our species recently has taken on the
attributes of a planetary geophysical force.
Few human activities produce a wider range of impacts than
our use of energy. Climate change – with its implications
for agriculture, disease vectors, collapsing ecosystems,
and (in the longer run) the possible collapse of the West
Antarctic ice shelf – is an energy- driven phenomenon. So
are acid rain, urban air pollution, hydroelectric flooding
of river valleys, and the proliferation of nuclear weapons.
Two billion people — 70 percent of the population in the
developing world — still rely on fuel wood, animal dung, and
kerosene for energy. These fuels can have profoundly
negative consequences for economic development and the
environment. In these 400 million Third World households,
noxious fumes from interior fires are a serious health
My job this morning is to sketch the contemporary energy
issue in a global context. Others will examine these issues
in greater detail. My overview will strive to provide a
sense of perspective.
THE REAL ENERGY ISSUE
The world today uses commercial energy at a rate of about 12
Terawatts. (One Terawatt-Year equals about 1 billion tons of
High Quality Coal, so each year we use the energy equivalent
of about 12 billion tons of coal.)
Notice the term I used: "commercial energy." This consciously
excludes much energy that is vital to life and civilization,
but is never bought or sold. The hydrological cycle that
purifies our water and grows our crops is not counted. The
sunlight that drives all photosynthesis is not counted.
If the sun didn't shine, your home would be a few hundred
degrees below zero when you turn on your furnace. Solar-
designed buildings collect and store more of this solar
energy than standard buildings, but all buildings get most
of their energy from the sun.
The flow of energy from the sun is so huge that it dwarfs
all commercial energy sources. Moreover, it is so dependable
that we can take it for granted. The amount of sunlight is
not at issue; the only real question is how well we will
Again, we currently use about 12 terawatts of commercial
energy. How much energy will we need a half-century from
Today, the average American uses energy at a rate of about
12 kilowatts. (That's all commercial energy for all uses by
all sectors of the economy, divided by all the people in
The average Swiss uses about 6 kilowatts.
But how much will we need 50 years from now?
Let's be robustly optimistic. Let's assume that within 50
years, all the buildings in the world have been replaced
by new, much more efficient buildings using passive solar
design and smart energy-saving devices.
Let's assume the world's transportation systems have been
entirely replaced by much more efficient new systems, not
dependent on gasoline.
Let's assume that the world's industries are employing
super-efficient technologies that have not yet even been
dreamed of, powering businesses as foreign as Microsoft
or Nokia would have seemed in 1950.
If we achieve the sort of energy efficiency revolution that
will be described in detail by others speakers at this
conference, the average person throughout the world could
be prosperous, comfortable, and productive a half century
from now using about 25 percent as much energy as the
average person uses wastefully in the United States today
-- or roughly half as much as is used by the average Swiss.
If we accept these assumptions, the answer for the year
2050 is 3 kilowatts/person -- worldwide.
Meanwhile, what is likely to happen to population? Let's
continue to be optimistic, and assume that the world's
population levels out at 10 billion people. Note: This
requires lowering the fertility rate down to replacement
values (2.1 children per woman) for the whole world by
This means overcoming fanatical religious, cultural,
nationalistic, and probably racial opposition. However, if
we fail to solve the population problem – and in the long
run that means reducing the human population to within the
long-term carrying capacity of the planet -- we cannot
hope to solve the energy problem.
OK, Let's do some simple mathematics.
Population kW/Person Total Terawatts
10 billion 3.30
In this scenario, which probably errors on the side of
radical optimism on all counts, we will need 30 Terawatts,
worldwide 50 years from now. Where can we get it?
About two-thirds of all unrecovered oil is now in the
Middle East. There has long been something approaching a
consensus that world oil production will peak sometime
between 2005 and 2015. Oil will be a minor contributor by
Similarly, conventional natural gas will be a minor
contributor by 2050.
Much methane is stored in unconventional deposits, as
"deep" gas or "tight" gas or in geopressurized brines.
Such gas will be neither cheap or environmentally clean,
and its problems will probably limit it to a minor role
in 2050 as well.
The earth has ample coal for coal to remain a major
energy source in 2050 -- but we shouldn't burn it.
Thirty terawatts would require the combustion of 30
billion metric tons of coal a year, increasing atmospheric
CO2 over today's base by about 3 percent per year --
enough to alarm even those who pooh pooh climate change.
Moreover, coal is even more unevenly distributed
geographically than oil, so a heavy global dependence
on coal era would imply political difficulties and
balance-of-trade problems for much of the world.
There is nowhere near enough Uranium-235 to meet a 30
terawatt demand, so a global nuclear power strategy would
require a substantial commitment to breeder reactors the
far-more-abundant U-238 into Plutonium-239.
Beyond the safety problems with breeders, they produce
fissionable isotopes that can be easily separated by
chemical means to make bombs. This much nuclear energy
would require enough plutonium to produce several million
nuclear bombs per year.
As India and Pakistan recently demonstrated, and Israel and
North Korea demonstrated earlier, nuclear power, sooner or
later, leads to nuclear bombs. A nuclear powered world would
be a terrifying world.
Hydropower now yields the thermal equivalent of 0.8
Terawatts. Ultimately, hydropower is unlikely to yield
more than 1 to 1.5 Terawatt.
Harnessable wind at acceptable locations will probably
grow to 1 to 1.5 TW -- the same order of magnitude as
Incidentally, in 1997, more new wind power capacity was
installed around the world than new nuclear capacity.
Germany is now the world leader.
Fusion reactors will not make a significant
contribution to a 30-terawatt world energy budget within
50 years -- if ever. The first generation will be
deuterium-tritium reactors with many of the same problems
as conventional light water reactors -- and they are likely
to run into the same opposition for the same reasons:
radioactive waste plutonium breeding, etc.
Moreover, it is impossible to imagine ways such awesomely
complicated devices could be made economically affordable.
We chose to ignore the sun earlier in this discussion.
However, in 2050 commercial solar energy will almost
certainly be our brightest energy source.
26,000 TW of sunlight falls on land. If we convert 1/2
of one percent of that at 20 percent efficiency, we can
harness 26 TW -- about enough to meet our optimistic
It is the only source likely to be able to make a
contribution of this magnitude.
Solar energy can be harness in many ways. Let me say just
a few words about what I consider the most promising solar
prospect – a technology to which I've devoted much of my
adult life: solar photovoltaic cells.
Solar cells are an astonishingly attractive energy source.
They consume no fuel; produce no pollution; generate no
radioactive waste or bomb-grade materials; have long
lifetimes; have no moving parts to break; require little
maintenance; and produce zero carbon dioxide – the
principle greenhouse gas.
But solar cells are expensive. How do we make them
affordable soon enough to complete such a massive, global
transition within 50 years?
The model to follow is that of the integrated circuit.
In 1961, a company named Texas Instruments began producing
integrated circuits for very small, specialized
applications. The private sector heaped scorn on those
early efforts. Referring to an early integrated circuit,
a director of Philips Electronics commented, "This thing
only replaces two transistors and three resistors and
costs $100. That's just crazy!"
But the American military recognized the potential
importance of small, lightweight, low-power integrated
circuits. It proceeded to purchase them in such quantities
that the price fell dramatically.
YEAR PRICE MILITARY %
1962 $50.00 100%
1963 $31.60 94%
1964 $18.50 85%
1965 $ 8.33 72%
1966 $ 5.05 53%
1967 $ 3.32 43%
1968 $ 2.33 37%
By 1971, a substantial commercial market had been built
for microelectronics; Intel introduced the first central
processing unit; and the personal computer revolution
Today, millions of people have more computational power
sitting on their desks than NASA had available for the
entire space program in the 1960s. This was possible
only because the government purchased truckloads of
expensive integrated circuits in the 1960s until economies
of mass production began to drive their costs down.
The same basic strategy -- government procurement pulling
the prices down the learning curve -- would work for solar
cells (which coincidentally are made of the same
semiconductor materials as computer chips).
A well-designed program to spend $6 billion on cost-
effective solar cells over the next four years could make
solar cells commercially viable for a significant fraction
of all new electrical applications worldwide.
For pocket change – literally $1 per person on Earth – we
could fundamentally alter the human prospect.
The world's governments should commit to buy $1 billion
worth in 1999 at $3/watt or less; $1.5 billion worth in
2000 at $2/watt or less; $1.5 billion worth in 2001 at
$1.50/watt or less; and $2 billion worth in 2002 at
$1.00/watt or less.
Such a program would do for solar cells what Defense
Department procurement did for integrated circuits.
When large-scale purchases lower the price of a product,
the change is permanent. Unlike tax credits and other
legislated loopholes, economies of mass production
cannot be repealed.
Part of the beauty of this "computer chip" solar strategy
is that, after a few years, no additional government
action would be needed.
But this initial governmental action will require a vast
outpouring of intense public support. The energy industry
is fiercely competitive and incredibly powerful.
Twenty years ago, conventional fuel companies successfully
crushed government programs that were aimed dramatically
accelerating the solar transition. In a recent talk to an
oil industry trade association, the Majority Leader of the
United States Senate dismissed solar energy as the "hippie
energy source." How do we overcome this opposition.
EARTH DAY 2000
One important instrument could be Earth Day 2000. Earth Day
will focus on a variety of global issues – and energy will
be among the most central.
The Earth Day 2000 campaign will pioneer techniques for
using the Internet as a global organizing tool. Sort of
like a global SUN-21, we will also disseminate the Earth
Day goals and programs through public service announcements,
feature articles, religious sermons, TV specials, school
curricula, concerts, plays, and every other avenue
of communication to which we can gain access.
Then, on April 22 itself, more than 200 million people in
150 countries will come together in the largest peacetime
event in history to demand that this millennium year be a
true turning point in our stewardship of the Earth.
In the United States, we plan to stage at least 40,000
events involving at least 80 million Americans --
including the largest rally ever held in Washington, DC.
We would be gratified if Switzerland were to make a similar
commitment to using Earth Day 2000 as a focal point of
efforts to create a balanced, healthy, sustainable future.
If you are interested, get out a pen. In just 30 seconds
I will tell you how to reach our web site.
After the first Earth Day in the United States, we passed
the Clean Air Act, the Clean Water Act, the Endangered
Species Act, the Resource Recovery and Conservation Act,
and established the Environmental Protection Agency. This
wave of change has caused has resulted in more than
$2 trillion being spent to improve the quality of the
The world is entering a time of unparalleled opportunity.
The East-West conflict that shaped and defined the last
half-century is now over. It is possible now to dare to
dream of replacing the Cold War with a Golden Age.
One can envision an attractive world in which:
- all energy is derived from renewable sources powered
directly or indirectly by the sun;
- the recycling of basic metals approaches 100 percent;
- paper is routinely recycled several times before being
consumed as fuel;
- a stable human population eats healthy, low-meat diets
that are within the biological carrying capacity of
- information-dense, super-efficient, pollution-free
technologies guide commerce, transportation, and
That is not the direction we currently are heading. But
Earth Day 2000 is setting out to change all that. In
about one month, you will be able to reach us at our initial
site at http://www.earthday.net .
I hope you will join us in using Earth Day 2000 to start
changing the course of human history.