Satellite presentationEnergy saving in a nuclear power plant

Arnoldus Lambertus Dipu

Topan Setiadipura

Massimiliano Zamengo

Thomas Bovis

Dissayapong Hoksuwan

Advantages of NCE

Advantages of NCE

• Release great amounts of energy

• Avoiding the environmental problems of fossil fuels

• No greenhouse gases are released by nuclear power plants

• Need less fuel than ones which burn fossil fuels

• Nuclear fuel is inexpensive

• Waste is highly compact

• The compact fuel is easy to transport

Source : www.ecolo.org/documents/documents_in_english/nuclear_advantage_Cohen.en.htm

Avoiding the environmental problems

of fossil fuels

• Global warming :

• Acid rain :

Fossil fuels

Burning

CO2 Increasing the earth’s temperature

Effect of global warming :

- Climate change ex. Increased areas will be affected by drought

and increased intense tropical cyclone activity etc.

- Sea level rise - Oxygen depletion

- Temperature rise

Fossil fuels

Burning

SO2, NOx

combine with moisture

Acid rain

Effect of acid rain :

- making lakes unlivable for fish and aquatic plants

- damaging forests

Source : www.alternate-energy-sources.com/advantages-of-nuclear-energy.html

Avoiding the environmental problems

of fossil fuels (cont.)

• Air pollution

Fossil fuels

Burning by power plant

Air pollution emission

Effect of air pollution :

- Causing illness and weakening

- Damages buildings, soils and clothing

- makes a dirty environment

Source : www.alternate-energy-sources.com/advantages-of-nuclear-energy.html

6

“This may sound too good to be true, but the U.S. has a renewable-

energy resource that is perfectly clean, remarkably cheap,

surprisingly abundant and immediately available. it's already proven

to be workable, scalable and cost-effective. And we don't need to

import it. […] This miracle juice goes by the distinctly boring name of

energy efficiency, and it's often ignored in the hubbub over

alternative fuels, the nuclear renaissance, T. Boone Pickens and the

green-tech economy. Clearly, it needs an agent. But it's a simple

concept: wasting less energy. ”

Michael Grunwald - reporter for The Washington Post

• Worldwide energy consumption was multiplied by three

over the last 40 years Source: Japan’s policy for Alternative Energy and Energy Conservation, Ichiro Ikemoto

• Proved reserves of energy resources are limited and

Coal, the most abundant one will be completely used in

2153Source: Japan’s policy for Alternative Energy and Energy Conservation, Ichiro Ikemoto

• This is the problem, our utilization of energy is

irresponsible

8

“The release of atomic energy has not created a new

problem. It has merely made more urgent the necessity of

solving an existing one.”

Albert Einstein - Physicist

9

• As of Feb 10, 2010 in 30 countries 436 nuclear

power plant units with an installed electric net

capacity of about 370 GW are in operation and

56 plants with an installed capacity of 52 GW are

in 15 countries under construction. Source: European Nuclear society (http://www.euronuclear.org/info/npp-ww.htm)

• It principally means that a little effort for

improving efficiency in Nuclear power plants

would have a great effect

Energy saving in a nuclear power

plant

• Increasing energy efficiency

– ACCW flow reduction

– ACCW discharge diversion

• Reutilization of waste energy

– District Heating

– Hydrogen production

Efficiency Improvement

• Auxiliary-condenser circulating-water

(ACCW) flow reduction;

• ACCW discharge diversion to the main

condenser;

PWR System

ACCW Flow Reduction

ACCW Flow Reduction

• To reduce circulating-water (CW) flow to

auxiliary condensers (thus to increase CW flow

to the main condenser to improve its vacuum),

so that the turbine electricity output could be

increased.

• Analysis shows that by ACCW reduction, the

plant electricity output can be increased by up to

839 kW at the CW temperature of 30oC.

(however this improvement is not consistent), it

decreases with CW inlet temperature.

ACCW discharge diversion

ACCW discharge diversion

• To redirect the ACCW discharge to the

main condenser instead of to the cooling

tower.

• Result in an electricity increase up to 1138

kW, and this increase is consistent for all

circulating-water temperature considered.

Presents: Massimiliano Zamengo

17

• What is district heating?

• How does it work?

• Evaluation of energy demand

• Expected energy saving

• Expected CO2 emission reduction

19

• The efficiency of a power station is about 40%

• Most of energy is released to the environment as heat

• Heat can be used to produce hot water

• Using a pipeline, hot water can be pumped to the nearest city

• Every house can take an amount of hot water through an heat exchanger

ElectricityElectricity

HeatHeat

• An amount of steam is bled from the turbine

SteamSteam

• Condensation heat warms up water for the grid

Hot waterHot water

20

21

• Surface: 50 m²

• Overall heat transfer coefficient (opaque components) 0.8 W/m²K

• Overall heat transfer coefficient (transparent components) 2.4 W/m²K

• Minimum winter temperature: -5 C

• Average numbers of hours for heating: 2160 h

• Air change: 0.5 vol/h

22

Energy need (heat)Energy need (heat) 4,700 kWh4,700 kWhtt

COP of heat pumpCOP of heat pump 3.53.5

Electricity requiredElectricity required 1,350 1,350 kWhkWhee

23

24

• Internal units works with hot water (fan coil unit, radiant floor, radiators)

• Hot sanitary water is available too

In this case we use just heat, In this case we use just heat,

NO ELECTRICITY or GAS!!!NO ELECTRICITY or GAS!!!

25

Using district heating allows to save

11,,350 350 kWhkWh of electricity

This corresponds to 670 670 kg of COkg of CO22

26

Turbine’s steam mass flow is a little less

The electricity output power is less

Electricity power output ~ 1000 MWe

Heat power output ~ 170 MWt

This is the power of 7,700 gas fired water heater!!!

• The available energy from hot water during winter season is 370,000 MWht

• The winter energy consumption of a “standard” apartment is 4,700 kWht

27

The available energy from the power station is enough for

7878,,000 000 apartmentsapartments

• Nuclear power station has no carbon emission

• Considering power station’s mix, it is assumed that 1 kWhe = 0.5 kg CO2

28

It is expected that for 78,000 apartments it is possible to avoid the emission of

5050,,000 000 ton of COton of CO22

29

Background:

Reutilization of heat energy can be done by coupling high

temperature electrolysis plant with nuclear reactor (PWR) to

produce Hydrogen

Higher thermal efficiency of Hydrogen production can be

reached under the steam phase than in water phase

The coupling of HTE plant with a PWR is possible in the

auto-thermal mode

30

Competitiveness:

Energy saving

It features a lower specific electricity consumption than

conventional electrolysis

Efficiency improvement

Gives additional value of increasing efficiency of PWR reactor as

well as increasing the efficiency of electrolysis plant

Clean Energy Technology

Large scale of hydrogen production, more pure hydrogen

produced with no consumption of fossil fuel, no production of

green house gasses and no other forms of air pollution.

31

Design:

Fig. 1. Principle of coupling of a HTE plant with a PWR (heat extraction from the

main steam header)

HP

Condenser

Reheater

LP

HTE Plant PWR Plant

Steam

Transformer

Steam

Process:

Heat extracted in the form of steam from the main steam header of PWR

(64 Bar, 280 °C)

HP

Condenser

Reheater

LP

HTE Plant PWR Plant

Steam

Transformer

280 °C

64 Bar

1608 kg/s

1574 kg/s

38 kg/s Xv = 1

280 °C, Xv = 1

Steam

226 °C

68 Bar152 °C

5 Bar

28 kg/s

152 °C

5 Bar

28 kg/s

Water

Process:

The steam condenses in the primary side of steam transformer at

the same temperature (280 °C)

HP

Condenser

Reheater

HTE Plant PWR Plant

Steam

Transformer

280 °C

64 Bar

1608 kg/s

1574 kg/s

38 kg/s Xv = 1

280 °C, Xv = 1

Steam

226 °C

68 Bar152 °C

5 Bar

28 kg/s

152 °C

5 Bar

28 kg/sLP

Water

Process:

In the secondary side steam transformer operates as steam generator

(Water is evaporated)

HP

Condenser

Reheater

HTE Plant PWR Plant

Steam

Transformer

280 °C

64 Bar

1608 kg/s

1574 kg/s

38 kg/s Xv = 1

280 °C, Xv = 1

Steam

226 °C

68 Bar152 °C

5 Bar

28 kg/s

152 °C

5 Bar

28 kg/sLP

Water

Process:

In the secondary side steam transformer water is evaporated in the same

temperature (152 °C)

HP

Condenser

Reheater

HTE Plant PWR Plant

Steam

Transformer

280 °C

64 Bar

1608 kg/s

1574 kg/s

38 kg/s Xv = 1

280 °C, Xv = 1

Steam

226 °C

68 Bar152 °C

5 Bar

28 kg/s

152 °C

5 Bar

28 kg/sLP

Water

Result:

Specific electricity consumption of HTE coupled with PWR:

3.2 kWh/Nm3 H2 which is less than the specific electricity consumption

of AWE (4.7 kWh/m3 H2)

Electricity saving: 1.5 kWh/m3 H2

Efficiency: 41.60%

37

Conclusion

• Energy saving per hour of production for

each measures :– Efficientcy improvement :

• ACCW flow reduction

Additional production of 839 kWhe ~ save 419.5 kg CO2

• ACCW discharge diversion

Additional production 1,138 kWhe ~ save 569 Kg CO2

– Reutilization of waste heat :

• District heating

Save production of 48 MWhe ~ save 24,000 kg CO2

• H2 production

Save production of 17.721 MWhe ~ save 8,860 kg CO2

Conclusion

Energy saving measures on the existing

NPP could be effective and make a

significant role in supporting the

sustainable development. This measures,

as of today, are still not implemented in

most of the existing plants.