Is global warming real?
+0,8°
So, if it is +0,1° on 90% of the surface and +10° over the poles, it is still 1 degree average but
thenBIG PROBLEM
Do we care about +1°?
If it is +1° everywhre, including the poles,
OK
The poles = 10% of earth’s surface
+4 to +7° at the North pole in January this year!
So, we don’t care about the global temperatureWhat matters is the increase at the poles
The heat is brought from the equator to the poles by the winds
Why are the poles getting warmer?
The earth is like a giant warm plate
cooled down by a small
and very cold spot
Any additional heat will concentrate at the poles
Grenoble (France) today
It was just 8° colder 2 km of ice!!! but 20,000 years ago…
So,what about if we get plus 4° in the future?
?Plus 1 degree is not much?
Where does all this mess come from?• Is it natural?• Hope not, because there would be nothing we can do!
• Or is it due to human being activities?• Most probably, even if some natural effect can overlap
A most probable culprit is CO2 which produces greenhouse effect
• Today, it is 1° per 100 years : 10 times faster!
• In the past, natural warming occurred at 10° per 10,000 years (or 1° per 1,000 years)
The greenhouse effect
Heat is trappedThe earth surface temperature would be -15 °C
without the greenhouse effect
Greenhouse effect = life
Without greenhouse effect
Risk of imbalance
Water vapor = 95%; CO2 = 4%
The earth is a greenhousethe glass is our atmosphere
The earth is in equilibrium
Sun heat
10 kg
Radiations
10 kg
Equilibrium temperature at the surface of the earth
= 15°C
But a peanut can have a large effect!!!The equilibrium is slowly broken
The temperature is rising
Human being effect is peanuts!
Carbon dioxide content is rising
We reject 35 billions tons of CO2per year
1 ppm =0,0001 %; 1% = 10,000 ppm
380 ppm is not much?
Still want to take a bath?
If you pour half a glass of wine into your bathtub…
That’s 380 ppm!
Let’s take a bath
We pump carbon from an
underground reservoir
We burn it at the surface to produce
energy
We dump it to the atmospheric
reservoir
Fossil fuel reservoir
almost infinite (if you accept to pay
the price)
Atmospheric reservoir
almost saturated
The problem is not a shortage of oil
But a shortage of air!
Who is polluting our greenhouse?
Road = 1/5th of total (cars = 10%)
Road = ¾ transportationTransportation = 28%
We need green cars• Electric cars represent a good solution– Storage of energy by batteries• Range limited to less than 200 km
• OK if the electricity comes from renewable sources
– Storage of energy by using Hydrogen• More than 600 km range
• H2 can be produced from renewable sources
Electrolysis : one way to produce Hydrogen
Oxydation at the anode
Reduction at the cathode
1,229 V
ELECTROLYSISWater + power H2 + O2
H2 + O2 Power + Water
FUEL CELL
A fuel cell : how does it work?
Hydrogen + Oxygen= electricity + water
1,229 V
H2O
H
Hydrogen fuel cell car
An electrical vehicle without battery•Hydrogen is stored in high pressure tanks (700 atmospheres)•Exhaust : only water vapor
•Can run 500 – 800 km 90-100 mph
X-TRAIL
FCHV
Clarity
Class-A
How to refill the car?
How to produce Hydrogen?
• By water electrolysis : expensive– Electricity from fossil, nuclear or renewable sources
• By cracking natural gas (CH4)– Releases CO2 , but saves 30% compared to burning gasoline
• Or ….
Once upon a time…CO2
biogas
bio-H2
Totally neutral and green
• So, there are plenty ways to reduce our C02 emissions
• Yes indeed, we can limit the global warming
• But will this be enough?
The internet cable network
Apple data center
Data centers in the world = 12 nuclear reactors1 billions PCs = 60 nuclear reactorsModem/routers: 18 nuclear reactors
5% worldwide electricity, rapidly growing
Telephone relay tower