Kernkraftwerk Gundremmingen
A location full of energy
Gundremmingen nuclear-power station
Kernkraftwerk Gundremmingen
Kernkraftwerk
Gundremmingen GmbH
Dr.-August-Weckesser-Straße 1
D-89355 Gundremmingen
T +49 8224 78-1
F +49 8244 78-2900
[email protected]
www.kkw-gundremmingen.de
Gundremmingen nuclear-power station
Contents
4
Electricity – Lifeline of our civilization
6
The energy mix – No simple recipe
8
Safe and dependable – The Gundremmingen nuclear-power station
9
Uranium – Rock full of energy
10
Nuclear fission – Slowdown for heat
11
Chain reaction – A handle on things
12
How a boiling-water reactor works
14
The cooling-water circuit
16
Dovetailed – The safety facilities
20
The environs – Under control at all times
22
Safety enjoys top priority – The disposal concept with the
Gundremmingen on-site interim storage facility
25
Important economic factor – Secure jobs
26
Technical data
27
Information on the location – Open for dialogue
View of a reactor-pressure vessel, opened for inspection. There are 784 fuel elements 28 metres below
the water surface. During the annual inspections, about one fifth of the fuel elements are exchanged.
2
3
Gundremmingen nuclear-power station
Electricity – Lifeline
of our civilization
Without electricity, it would be “no systems go” today. Electricity becomes light,
electricity is heat, is power. Electricity
controls and regulates, transports information.
Electricity is needed if we are to use other energy sources in a sensible
and economical way. We need electricity to utilize ambient heat, solar
and wind energy. And, not least: electricity is emission-free at its
place of use.
All of these unique, typical properties of electricity have meant that
the demand for this precious energy both from households and from
business and industry has grown steadily over recent decades:
electricity has found new areas of application, has replaced other
energy carriers or enabled their sparing use. And this has had a
positive impact on developments in overall energy consumption,
which has expanded much more slowly since 1970.
Energy is the lifeline of our civilization. All the more important, then,
that affordable electricity should be available for each and every
one of us around the clock. However, electricity cannot be stored
(or only with difficulty), so it must be generated in the amount that
happens to be needed. Utilities have assumed the task of producing
and supplying energy. To the fore in this service, besides a dependable, secure and low-cost supply, we find environmental protection
and sparing use of raw materials as equal-ranking goals today.
Ultimately, it is up to each individual to make sensible and sparing
use of electricity. The utilities support this with comprehensive customer advice, and manufacturing industry is developing ever thriftier
machines and appliances.
In Bavaria, nuclear energy and hydropower, with a share of 66 and
15 percent resp., are the most important pillars of power generation.
Coal, with some 8 percent tends to play a subordinate role, while oil
and gas are primarily used for short-term demand peaks. This energy
mix is economical and environmentally friendly. More than 80 percent
of Bavaria's power is produced without air pollutants, i.e. without
harming the climate.
Germany reported the following shares in 2007 power generation:
24 percent nuclear energy, 26 percent lignite, 22 percent hard coal,
10 percent natural gas, 15 percent renewable energy, 3 percent fuel
oil, pumped storage and other.
Net power generation in Bavaria
Shares of power plants, 2007, in %
Hydropower 15.3 %
Hard coal*
7.6 %
Natural gas
9.6 %
Oil
1.6 %
Nuclear energy
65.9 %
*) incl refuse, renewable and other energy sources
Source: BayLfStaD
4
5
The energy mix – No simple recipe
Be it coal, gas, nuclear energy or renewables – every energy source
is marked by advantages and drawbacks, sweet spots and weak
spots. So, only one solution can survive in the long run: a balanced
mix of different energy carriers.
Many sources feed the current. And not only today, but in future as
well – a future of modern, climate-sparing energy generation. In the
long term, most energy will continue to bubble up from the well of
fossil fuels, including coal and gas. They have emerged from the
conversion of dead organisms – over millions of years. Because they
are being used up faster than they are renewed, their reserves are
finite. Moreover, their use is associated with the emission of greenhouse gases like CO2.
A balanced energy mix is also needed for the technical structure of
the power supply: the strong seasonal and also daily fluctuations in
electricity consumption can be cushioned in only one way: by having
a mix of different power-plant types. How that works? By distributing the load of the energy demand between power plants. This means
that a specific power plant is in charge of one of the three loads:
Summer day
Winter day
Peak load
Peak-load power plants help out when energy
demand reaches maximum values for a short time.
Only quick-starters can keep pace with such a rise:
gas turbine and pumped-storage power plants.
Just a few seconds – and they have reached their
full output.
Intermediate load
Intermediate-load power plants produce the
energy add-ons if demand increases. This intermediate-load demand is mainly covered by hard-coal
and gas power stations in the minute to hour range.
Base load
Many countries’ energy grids are fed by a sizeable chunk of nuclear
power: relatively low-cost, readily available and sparing the climate,
since there are no CO2 emissions. In Germany, nuclear energy’s use
is time-limited due to the country’s Atomic Energy Act. In the medium term, this climate-friendly, safe and economic energy source is
set to dry up there.
Base-load power plants are the most important
ingredient in the power-station mix. Having a high,
continuous output and, hence, favourable costs,
they cover the basic demand for electricity – the
day job of nuclear-power stations, lignite-fired and
run-of-river power plants.
Start of work
Also foreseeable is the growing contribution to be made by renewable energy. It cannot be exhausted by human consumption. Either
because it is available in large amounts – like solar energy and wind
– or because it continuously renews itself, like hydropower and biomass.
0
2
4
6
8
10 12 14 16 18 20 22 24
0
2
4
6
8
Watching TV
Anyone out to produce energy on a sustainable basis must reconcile
these goals – no mean feat. Depending on which goals you take as
your base, you will set your own course for a future-proof energy
supply. Sometimes security of supply will be more to the fore, at other
times environmental protection perhaps. A look ahead will always
face us with one central task: responsibility for the sustainability of
Germany’s, but also the world's, energy supply.
Underlying technical conditions
Lunch
Environmental protection, security of
supply, economic efficiency – these are
the three goals in power generation.
10 12 14 16 18 20 22 24 Uhr
Electricity demand curve on a typical summer and winter day
6
7
Gundremmingen nuclear-power station
1 kg of natural uranium
Safe and dependable –
The Gundremmingen
nuclear-power station
An ideal power-plant location must meet several preconditions:
proximity to the extra-high voltage system and consumers, good
traffic link-ups and a river in the immediate vicinity – and all are
met by the Gundremmingen municipality near Günzburg between
Augsburg and Ulm. So, alongside the now shut down 250-megawatt
nuclear-power station – unit A – construction was able to start in
1976 at Gundremmingen on two new boiling-water reactor units
with an output of 1,344 MW each.
The power-plant terrain, measuring some 35 hectares, is at an elevation of 433 metres, embedded in a forestry and agricultural setting.
The proximity of both motorway and railway makes the transportation of heavy goods easier.
Little less than a kilometre away flows the Danube, whose water
helps to cool the two units. To ensure that the amount of heat
discharged into the river does not rise beyond a level that is still
compatible with flora and fauna, two natural-draught wet cooling
towers were built at Gundremmingen.
is equivalent to
12,600 l of crude oil
In 1984, the two units went on stream after an 8-year construction
period. Ever since, they have been producing – dependably, safely
and without emitting pollutants – an average of 21 billion kWh of
electricity per year. This is equivalent to about 30% of Bavaria's
annual power consumption. At the same time, the power station –
compared with electricity production from fossil fuels – avoids
emissions of some 21 million tonnes of carbon dioxide every year.
Safety enjoys top priority in operating the power plant. A workforce
of about 1,100 at the location, with high competence and pronounced
safety awareness, makes a crucial contribution toward this.
Operator of the plant is Kernkraftwerke Gundremmingen GmbH
(KGG), which belongs to RWE Power AG in Essen with a 75 percent
share, and to E.ON Kernkraft GmbH in Hanover with 25 percent.
or 18,900 kg of hard coal
Uranium – Rock full of energy
Nuclear-power stations utilize the energy that is released in the fission
of the nucleus of the naturally occurring radionuclide uranium-235.
Uranium is a heavy metal that is embedded in ores and deposited
relatively evenly across the earth, and it can be mined. As today’s
knowledge stands, the fuel uranium will be available for at least
another 200 years. Thanks to the continuous further development
of the technology used to locate and mine uranium, a much longer
reach may be expected.
Uranium has a very high energy density, i.e. a very high energy content. One kilogramme of natural uranium has an energy content
equivalent to that of 12,600 litres of crude oil or 18,900 kilograms of
hard coal.
Unlike other energy-conversion technologies, nuclear energy’s
competitiveness is not impaired when fuel costs rise. The share of
uranium in the electricity-generation costs of a power station
amounts to a mere 3 to 5 percent. This means that increases in the
price of fuel have only very little impact. Even a doubling of the rawmaterial price would have hardly any effect on power-generation
costs.
The uranium extracted from ores consists of 0.7 percent fissionable
uranium-235, the rest being uranium-238. Thanks to enrichment,
the share of uranium-235 is raised to 3 to 5 percent in the mixture
with uranium-238. The enriched uranium is pressed into pellet form
and filled into rods of an especially resistant material (zircaloy). These
fuel rods are bundled to form fuel elements and can be used in this
form in a nuclear-power station.
8
9
Gundremmingen nuclear-power station
Gundremmingen nuclear-power station
Nuclear fission of uranium-235
Chain reaction –
A handle on things
Controlled chain reaction
The more neutrons there are, the more fissions occur and the more
energy is released. Since more neutrons emerge in uranium fission
than are needed to maintain a controlled chain reaction, some of
the neutrons are deflected from their actual target.
To this end, control rods are used in a nuclear-power station’s reactor.
They consist of a material (boron, hafnium) that sucks up the neutrons, i.e. absorbs them. To lower reactor output, these rods are inserted into the reactor; to increase it, they are pulled out again.
Slow-moving neutron
Uranium
Fission Fast-moving
products neutron
Moderator
Control rod
Nuclear fission is interrupted when they are inserted. A reactor
works at max. output when the rods are removed.
In operation, the control rods are powered by electric drives; independent of this, a hydraulic system is available for emergency shutdown.
There is however a second way to control and regulate the chain
reaction: the hotter the moderator or the cooling agent becomes,
the more steam voids emerge. Steam, unlike water, is unable to
slow down the neutrons sufficiently, and more and more neutrons
miss their target.
Nuclear fission –
Slowdown for heat
There is nothing mysterious going on in the reactor of a nuclearpower station. As in other power plants, man is using technical
means to exploit natural occurrences.
Water lends itself as neutron brake – acting as moderator, in the
jargon. It helps reduce the velocity of the neutrons to a speed that
is right for fission.
When neutrons strike a uranium-235 nucleus at a relatively low speed,
we speak of nuclear fission – an event that also occurs in nature.
Each fission produces two to three new neutrons which trigger
further fissions. This gives rise to a self-sustaining chain reaction.
In the process, uranium-236 emerges, and this splits into two pieces
which, in their turn, scatter at high speed, to be slowed down by other
atoms in the vicinity. Thanks to this braking action, the kinetic energy
produced is turned into utilizable heat to generate power. The whole
process only works, however, if it is possible to check the frantic
speed of the neutrons, so that they do not miss their target, the
uranium nucleus.
Chicago, 1942: The physicist Enrico Fermi masters the first selfsustaining chain reaction in Chicago in 1942. But long before man
existed, namely two billion years ago, uranium-235 was fissioning
in nature by itself in West Africa's Gabon, where scientists have discovered several natural reactors.
10
This physical occurrence is exploited by the dosed addition of cooling water. More water means a lower temperature, which results in
a higher hit rate of the neutrons. A lower amount leads to faster
heating of the water. This leads to more steam voids, which lowers
the hit rate. Behind this principle lies a crucial safety element in a
boiling-water reactor: in any loss of water, the chain reaction stops
by itself.
Finally, there is a third way to shut down the reactor fast at any time:
a boron solution is pumped in, which absorbs the neutrons and
interrupts the fissioning of the uranium cores.
Control rods lowered
Control rods lifted
Moderator temperature high
Moderator temperature low
Fission processes low to none
Fission processes increased
Fission processes low to none
Fission processes increased
Fuelelements
Control
rods
Fission
processes
Neutron
release
Water molecules
Neutron
11
Gundremmingen nuclear-power station
How a boiling-water
reactor works
The two boiling-water reactor units B and C in Gundremmingen are
identical in design. The core in each case is the reactor-pressure
vessel, which is roughly two thirds filled with water. This steel cylinder,
clad in a solid concrete shell, the so-called biological shield, contains
the bundled fuel elements. Each fuel element is 4.47 metres high
and consists of up to 96 fuel rods filled with uranium pellets. In total,
each reactor contains 784 fuel elements each.
During core fission in the fuel rods of the reactor core, heat is released
that sets the reactor water boiling – a process similar to that in an
immersion heater. The water flows from bottom to top through the
reactor core and takes the heat developed in the fuel rods with it.
Some of the water evaporates.
After the steam is separated from the water in the upper part of the
pressure vessel, the pure water vapour flows to the turbine and sets it
rotating – as wind does with a wind turbine – by driving the rotors of
the turbine shafts. Thermal energy is transformed into kinetic energy.
Reactor building
Refuelling
machine
The turbine is coupled to the generator via the turbine shaft in
which the mechanical energy is translated into electric energy
through a strongly rotating magnetic field – designed on the principle
of a push-bike dynamo. Its voltage is increased via a generator transformer, transferred to the near-by transformer station and fed into
the public supply grid. Increasing the voltage is necessary because
electricity can only be transported across long distances in this
form.
Once a year, each power plant unit is shut down for some two to
four weeks for inspection and exchange of the fuel elements. About
one fifth of the fuel elements are replaced. During the entire inspection and maintenance work and in the recurrent checks, some
1,500 further specialists from third-party companies are deployed
in addition to our own staff.
Cooling tower
Turbine house
Fuel-storage
pool
Turbine
Generator
Transformer
Steam
Cooling water
Water
Suppression
Reactor- Containment
chamber pressure vessel
Feed-water
pump
Condenser
Cooling-water
pump
A look inside the turbine house of the 1,344-MW turbine generator set: the steam from the reactor flows through
the high-pressure section (not visible in the background), then the turbine's two low-pressure sections, and subsequently condenses in the condensers below. Shown in the foreground is the generator with an exciter.
12
13
Gundremmingen nuclear-power station
The cooling-water circuit
In the condenser behind the turbine, the steam gives off its residual
heat to the cooling water and becomes water again which then
makes its way through the reactor anew. The heated cooling water
is cooled off again in the cooling tower.
The two cooling towers at Gundremmingen are 160 metres tall. The
heated cooling water flows into the cooling towers, is pumped 12
metres upwards and trickles via down slabs into a collecting tank.
The cooling towers at Gundremmingen are natural-draught wet
cooling towers that make use of a naturally rising air draught to
cool the water. Additional components like fans are not necessary.
In the draught, the droplets of the warm cooling water cool off. In
the process, some of the cooling water evaporates and is yanked
upward with the draught: in this way, depending on the weather, a
typical vapour plume will emerge. Most of the water by far is pumped
back to the condenser. The evaporation loss occurring in the cooling
tower is offset by cleaned water from the Danube.
from the condenser
to the condenser
14
15
Gundremmingen nuclear-power station
Dovetailed –
The safety facilities
Ensuring a high safety standard is the central obligation of any
nuclear-power station operator. The basis of the high safety level is
a high-quality technical design that reliably avoids incidents. In addition, the downtimes of systems and components are considered
"up front" already, and it is ensured that they have no impact on
their surroundings. Comprehensive inspection and maintenance
programmes help keep the plant in an optimal condition at all times
and detect and remedy any irregularities in plant components early
on. Besides guaranteeing an excellent technical condition, the operator’s efforts also focus on organizational issues and a high safety
awareness among plant staff.
What is more, operation of the nuclear-power stations is stringently
monitored by the authorities in charge.
The design principles
By way of precaution, the designs of a nuclear-power stations always
assume a coincidence of unfavourable circumstances and damage
events. This being so, engineering and construction are based on
the design principles: redundancy, diversity, spatial separation and
fail-safe (so-called passive safety).
Diversity: different systems have the task of performing the same
function. If, for instance, the insertion of the control rods fails
using the electric motors provided for this purpose, they are
put in place by a hydraulic system. In the long term, the reactor
can also be switched off safely by pumping in a boron solution.
Fail-safe: all safety systems unfold their effect in a safe direction
should a disruption occur. In the event of a power cut, say, the
control rods are inserted into the reactor using a hydraulic system
which kicks in automatically in any power failure.
Diversity
Redundancy
Cooling systems
Redundancy: several systems of the same kind are in place to
do the same job. In an emergency, one takes over from the other.
At Gundremmingen, for example, there are three emergency
cooling systems operating independently of one another, any
one of which can step in should the main cooling system fail –
two remain on standby
Additional
system
Boron
solution Control rods
Fail-safe
Reactor
Electrically shut
valve
High-pressure
nitrogen
The control room lives up to its name: modern control engineering handles the processing of all
information and measured values that crop up and ensures largely automated operations.
16
17
Gundremmingen nuclear-power station
Reactor building
Biological shield
(wall thickness: 1 m)
Steel lining
Containment
(pre-stressed
concrete: 1.2 m)
Reactor building
(wall thickness: 1.8 m
Reactorpressure vessel
Pressuresuppression system
Residual
3,000 m³
heat-removal
water
system
reserve
Fuel elements
with fuel pellets
Having a spatial separation of the redundant and diversitary facilities ensures that several systems cannot fail simultaneously
due to one cause.
The safety facilities
Every nuclear plant is equipped with numerous safety facilities. Extreme requirements must be met by a nuclear-power station’s design. The aim of all safety measures in nuclear reactors is to retain
the radioactive materials that arise in nuclear fission in the reactor
core.
For this, the following retention barriers are in place:
the fuel’s crystal lattice, which retains most of the fission products
the gas-tight and pressure-proof metal casing around the fuel
pellets (fuel rod)
Earthquake-proof
bottom slab
the biological shield: a 1-m-thick concrete shell
the containment consisting of some 1.2-m-thick reinforced
concrete with a jacket of 16,000 pre-stressing steel rods
the reactor building with 1.8-m-thick reinforced concrete.
The reactor-protection system
Every nuclear-power station is additionally equipped with a reactorprotection system. During operation, it checks on an ongoing basis
all important measurement values, compares them with the target
state and corrects any anomalous operating states it detects. If certain
limits precisely defined in advance are reached, the reactor-protection system automatically triggers active safety measures – e.g. a
reactor emergency shut-down or emergency power supply.
Safety facilities and safety measures are systematically checked to
ensure operatability by a stipulated programme of recurrent audits.
the reactor-pressure vessel with closed cooling circuit
Look into the fuel-element pool. The exchange of the fuel elements is
controlled and monitored by a fuel-charging machine.
18
19
The environs –
Under control at all times
Although the Gundremmingen nuclear-power station emits only
the minutest amounts of radioactive radiation, the entire surroundings of the plant are monitored by our in-house laboratory and by
independent institutions. In fact, even the strict approval values are
far undercut in Gundremmingen at all times, as evidenced by test
samples taken from the soil, air and water in the plant's environs.
Like all atomic reactors in Bavaria, Gundremmingen, too, is linked
to the nuclear-reactor telemonitoring system of Bavaria’s State Office
for Environmental Protection. At regular intervals, measured values
from the plant's environs are automatically read, transmitted to
Augsburg by radio and evaluated by the authority. All results of
this evaluation are accessible to the public.
20
21
Gundremmingen nuclear-power station
Safety enjoys top priority –
The disposal concept with
the Gundremmingen on-site
interim storage facility
According to the disposal concept for nuclear-power stations, radioactive waste from nuclear reactors is to be enclosed indefinitely and
safely in final (permanent) storage sites. The federal government has
given an undertaking to make available final storage sites by 2030 at
the latest. Pending such time, spent fuel elements must be kept in
temporary storage sites. For this purpose, an on-site interim storage
facility was built on the premises of the Gundremmingen nuclearpower station to house the spent fuel elements from the nuclear
reactor until they are transported to the final storage site.
The core of the interim storage facility’s safety concept goes by the
name of CASTOR. CASTOR is a special container for fuel elements.
The type envisaged for Gundremmingen can hold 52 fuel elements
and has stood the test hitherto. It shields the radiation of the spent
fuel elements so well that you can stand in the immediate vicinity of
a CASTOR without coming to harm. Its design and the outstanding
properties of the material used have proved their worth for years
now both in the transportation of retired fuel elements and in their
temporary storage. CASTOR has evidenced its safety in numerous
tests. It must, for example, withstand a fall from a height of nine
metres on to an unyielding base and survive intact a fire with a temperature of at least 800 °C. In addition, CASTOR withstands an earthquake, as it does a plane crash.
Airlock of the on-site interim storage facility to hold the spent fuel elements packed in CASTOR containers
22
23
Castor
Double-lid system
Main Body
Basket
5.86 m
Moderator rod
Cooling ribs
2.44 m
The storage building is located on the power-plant grounds to the
side of the reactor building of unit C in front of the cooling towers.
It is 104 metres long, 38 metres wide and 18 metres high. The building
is divided into a loading hall and two halls for holding CASTOR containers with spent fuel elements. Seen from the outside, the building
looks like a conventional industrial hall. With its 85-cm-strong outer
walls and its 55-cm-thick concrete roof, however, the storage building
is of a very robust design. Every year, the Gundremmingen power
plant produces an average of five to six CASTOR containers with
retired fuel elements.
The interim storage facility offers space for max. 192 CASTOR containers, so that the system is planned at all events so as to take fuel
elements from the Gundremmingen power plant for its entire remaining technical and economic operating life.
Gundremmingen consumes about 300 fuel elements a year. After
leaving the reactor, they are taken to the fuel-storage pool inside
the reactor building. There they stay for about five years before
24
being packed into the CASTOR containers and placed in the on-site
interim storage facility. The casks have two overlying lids fitted with
special seals. An additional guard plate prevents dust and moisture
reaching the lid system during storage. The tightness of the doublelid system is constantly checked by an automated monitoring system
during the entire storage period.
For people living in the area of the power station, there is no additional measurable radiation burden. This will still hold true when
the interim storage facility is completely full. Even if you were to
spend a whole year at the nearest generally accessible location, the
additional radiation, viz. just 0.1 millisievert, would be very small.
This is roughly equivalent to a simple x-ray photo. The average, natural radiation to which everyone is exposed in Germany is 2.4 millisievert a year. Even inside the building, the exposure is so low that
the operating team can work there without being harmed. The permissible limit values under Germany's Radiation Protection Ordinance
are easily undercut.
Important economic factor –
Secure jobs
The Gundremmingen nuclear-power station is an important economic factor in the region. The plant secures the jobs of some 780 inhouse staff as well as 360 specialists in third-party companies that
are constantly represented on the site. To this must be added a further
1,000 jobs with numerous suppliers and service providers. The order
volume to firms in the region totals around € 25 million annually.
What is more, the location offers interesting training places for
young people.
25
Gundremmingen nuclear-power station
Gundremmingen nuclear-power station
Technical data
Overall plant
Control elements
Thermal output of the reactor
MW
3,840
Number of control elements
Gross electric output
MW
1,344
Absorber length
Net electric output
MW
1,284
Absorber material
Gross efficiency
%
35
Control lift
mm
Auxiliary requirements unit A
MW
60
Normal insertion speed
cm/s
unit B
MW
56
Normal insertion time
s
Emergency shut-down speed
cm/s
Insertion time in emergency shut-down
s
3.2
Design pressure
barü
3.3
Inside diameter
m
29
Clearance
m
32.5
Nuclear steam-generation system
Pressure at the pressure-vessel outlet
bar
Saturated-steam temperature at the
pressure-vessel outlet
°C
Flow rate through the core
kg/s
14,300
Steam quantity at the pressure-vessel outlet
kg/s
2,077
Steam moisture at the pressure-vessel outlet
% wt.
Final feed-water temperature
°C
69.6
193
mm
3,660
Boron and hafnium
3,660
3
122
approx.
120
Containment
286
0.02
Material
Information on the location –
Open for dialogue
Pre-stressed concrete with steel liner
As power-plant operator and major employer, we are part of the
region in the Günzburg district. A trusting and partnership-based
relationship with the population and an open dialogue with all those
interested are among our central concerns. Here, the information
centre of the Gundremmingen nuclear-power station serves as communication platform. Our competent and committed staff are ready
to answer any questions, and not just on technical issues. Also to
the fore of the complex discussions are various subjects round and
about energy.
215
Steam-power system
Reactor core
Number of fuel elements
784
Number of control rods
193
Uranium dioxide/mixed oxide
Fuels
Total fuel weight
t
approx.
Steam quantity at turbine inlet
kg/s
Steam pressure at turbine inlet
barü
Steam temperature at turbine inlet
°C
Steam moisture at turbine inlet
% wt.
1,944
66
0.02
136
Turbine
Fuel elements
Type
Total length
mm
4,470
Cross-section surface without boxes
mm
131x131
Number of fuel rods per fuel element
80 to 96
Total weight without box
kg
approx.
255
Fuel weight, uranium fuel elements
kg
approx.
Fuel weight, MOX fuel elements
kg
approx.
Fissionable share of the uranium fuel elements
% wt.
3.13 – 4.6
Fissionable share of the MOX fuel elements
% wt.
3.27 – 5.47
172
173
Reactor-pressure vessel
1
Speed
s1
Rated power
MW
1,344
mm
1,350
Number of casings, HP/LP
Last-stage blade length
mm
6,620
Clearance
mm
22,350
Number of steam extractions, HP/LP
Design pressure
barü
Design temperature
°C
Cylinder-wall thickness and cladding
mm
Top-head wall thickness and cladding
mm
90 + 8
Bottom-head wall thickness and cladding
mm
228 + 8
86.3
300
163 + 8
22 NiMoCr 37
Material
t
785
Main coolant pumps
°C
Cooling-water quantity for condensation
kg/s
Type
bar
1
Speed
s1
Apparent power
MVA
cos phi
kV
Frequency
Hz
Axial-flow pump
Cooling for stator core
Cooling for rotor
Static delivery head
mFIS
Nominal speed
min
1,838
Coupling power, normal operation
kW
1,030
8,731
31.1
1,640
27
50
H2O
H2
H2O
Steam and feed-water circuit
Number of HP/LP heater trains
2/2
Number of heater stages
5
Number of feed-water pumps
%
3 × 50
Number of condensate pumps
%
3 × 50
%
3 × 331/3
Number of condensate-polishing filters
Number of main cooling-water pumps
26
25
0.85
Voltage
Cone-flow pump
m3/h
0.08
Four-pole rotary-current generator
Number
unit B
Circulation amount per pump
43,900
Opening times of the information centre:
Mondays to Fridays 9:00 to 16:00 hrs
Saturdays and Sundays 13:00 to 18:00 hrs
closed on holidays
Generator
Pump type unit A
8
24.4
2
Cooling for stator winding
Number of pumps
Kernkraftwerk Gundremmingen GmbH
Informationszentrum
Dr.-August-Weckesser-Strasse 1
D-89355 Gundremmingen
T: +49 8224 78-2231
F: +49 8224 78-3565
[email protected]
www.kkw-gundremmingen.de
2/3
Mean cooling-water inlet temperature
Condenser pressure (absolute)
25
1/2
Number of condensers
Inside diameter
Total weight
Condensing reaction turbine
Number
We look forward to your visit!
286
4
27