Safe design of technology for hydrogen as a green energy carrier
can you imagine a world without fossil
fuels
we might not go around thinking about
this but it’s an interesting thought
what should we then use as energy for
transport
for power and for heating
we see here the extent of the fossil
energy production in the world for one
year and this unit mto is the energy
equivalent of a million tons of
oil which is a staggeringly large unit
now fossil fuels are not renewable
energy sources
and the use of them produced co2 and
other climate gases
and at the moment our energy supply is
from burning things we find in the
ground
and that’s really not sustainable in the
long run
now let’s compare the fossil energy
production to the renewable energy
production
as you can see the amount of renewable
energy production in the world is
very low compared to the non-renewable
energy and especially fossil fuels
even though the production of renewable
energy is increasing
now since the world’s energy demand is
also increasing we still have a long way
to go
to be able to make the world independent
of fossil fuels
the world is now trying to find
alternatives for these fossil fuels
and the most likely solution is
renewable electricity
and that is electricity from solar wind
tide
and many other sources now these are
great sources for producing electricity
but we need to be able to transport
and store our energy in a practical way
and the promising solution to store and
transport electrical energy is by making
hydrogen
from electricity and water a hydrogen
can be stored
as a gas or a liquid and when you use
that to produce electricity in the fuel
cell
for the power exhaust is only pure water
now several local national governments
are now seeing if this can be one of the
solutions to reduce our dependency on
fossil fuels
and hydrogen from renewable electricity
really is a great solution for deer
carbonization
we can fill our cars our ships planes or
trains just like with petroleum fuel
and the cost will probably not be
significantly higher
and this is the part that we can call
the hydrogen economy
but what i really want to talk about is
hydrogen safety
one challenge of introducing hydrogen
for fuel is that hydrogen is a
combustible gas
hydrogen is safe as long as it’s
contained in tanks or in equipment
but if an accidental release of hydrogen
from failing equipment
we lose containment and release hydrogen
can form explosive clouds if mixed with
air
hydrogen is also very reactive so that
the potential explosion can be quite
severe
however this chemical property that
makes hydrogen
this reactive also makes it a great fuel
for a new fuel to get public acceptance
the risk of using the fuel will need to
be as
low or lower as for a traditional
alternative
since hydrogen behaves very differently
than for instance gasoline
we need to think about safety in a
different way
through our group’s research we are
studying how the design of systems are
influencing the effect of loss of
containment
and the goal of our research is to make
applications like
cars or ships and constructions like
parking houses and tunnels
safe to use for hydrogen i’d like to
show an example of our research into the
effects of the sign on explosions
in these experiments a hydrogen was
released inside the container
with obstacles this picture shows the
inside of the container where these
pallets are simulating different types
of equipment
inside the room hydrogen was released
inside and then
ignited after letting it mix with air
now let’s see what happened
the amount of hydrogen released was 300
grams
and the explosion pressure was large
enough to lift the container off ground
even though the door was open the
explosion was quite
severe if we remove this obstacle
inside the container and repeat the
experiment we can clearly see
a huge difference the container is now
completely empty and the door is still
open
it’s not that easy to see what happened
was it there is hardly any effect from
the explosion
for the first experiment the obstacles
inside restrict the flow of gases
out of the room and cause a stronger
pressure buildup inside
this stronger pressure buildup will lead
to more severe
explosion without the obstacles the gas
can freely leave
and there are nearly no effect of an
explosion
this knowledge is important to make sure
we can create a safe environment for
hydrogen as a new fuel
we need to make sure that we understand
the physical effects that control the
consequences of an incident so that we
can make sure that the design of
equipment and possibly surroundings is
safe for people
and society and the devil really is in
the details when designing safe systems
for combustible gases
like hydrogen you must always design an
application or system by taking into
account that unwanted leaks of hydrogen
can happen
this can happen due to collisions
external fires or
failing equipment other reasons the
preferred design feature is of course
as long as you can freely that hydrogen
float away smaller releases
are not dangerous at all but this might
not be possible
if we need to have a room like the
container in the videos
it is critically important that we
design these structures to be able to
minimize the effects of
incidents like unwanted hydrogen
releases
and like we saw in this video some
obstacles inside the room will
significantly increase the effect of an
explosion
even though the door was open for the
gas to leave
it was ventilated so without obstacles
there was hardly an explosion at all
to bring the knowledge we have gained
through our research and new knowledge
from future research
is critical to introduce hydrogen into
society in a safe manner
the world’s goal should be to bring our
energy production from fossil fuel to
renewable sources
and hydrogen looks to be part of this
transition to bring a renewable fuel to
the public
to gain public acceptance for the new
fuels a safe introduction
is crucial technology development will
have to
include safe design of all parts of the
value chain from production to consumer
so that accidents will not happen and
will not be a show stopper
you