From Asahi Shimbun,  · From Asahi Shimbun, ... Area Supply(GW) Case1 Case 2 Case 3 Hokkaido 4.85...

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Toward Stable Supply of Electrical Energy Following the March 11 Earthquake Shintaro Furusaki Professor Emeritus, The University of Tokyo WFEO-ICESEDC 2013, Guangzhou September 7, 2013

Transcript of From Asahi Shimbun,  · From Asahi Shimbun, ... Area Supply(GW) Case1 Case 2 Case 3 Hokkaido 4.85...

Toward Stable Supply of Electrical EnergyFollowing the March 11 Earthquake

Shintaro FurusakiProfessor Emeritus, The University of Tokyo

WFEO-ICESEDC 2013, GuangzhouSeptember 7, 2013

From Asahi Shimbun, www.asahi.com

www.hirobro.com/arvhives/51458275.html

Annual Consumption of Electricity in Japan

Total primary energy consumption= 22,000 PJ (22 EJ) decreasing since 2007

Primary energy to produce electricity = 10 EJ (44% of the above)

Supply of electricity = 4 EJ (40% efficiency of production)

Expected consumption by saving energy= 3.6 EJ (3600 PJ) = 1000 TWh

(cf. 1 kWh = 3.6 MJ, 1 TWh/y = 114 MW)

Contents

1.Supply and Demand of Electrical Energy in Japan

2.Safety of Nuclear Power Plants in Japan3.Problems and Possibility of Natural Energy4.Saving Energy5.Scenario toward the Energy System in the   Low‐Carbon Society

6.Summary

Expectation of Electric Supply Balance (August 2012: %)

Area Supply(GW) Case1 Case 2 Case 3Hokkaido 4.85 -4.3 -3.1 0.1Tohoku 14.75 -0.6 2.9 9.3Tokyo 57.71 -3.1 4.5 7.7Central 27.85 3.3 5.2 7.7Kansai 25.35 -18.4 -16.3 -13.5Hokuriku 5.78 0.9 3.6 7.5Chugoku 12.35 2.6 4.5 7.9Shikoku 5.87 -1.7 0.3 4.5Kyushu 15.74 -12.1 -3.7 0.6Average 170.25 -5.2 -0.4 2.6

Case 1: Intense heat Case 2: Intense heat with energy savingCase 3: Moderate heat with energy savingIn all cases nuclear power plants are not in operation.

Data from Federation of Electric Power Companies (FEPC)

Expectation of Electric Supply Balance (2013: %)

Area Supply(GW)1 July August SeptemberHokkaido 5.06 9.6 10.5 11.0Tohoku 14.95 5.0 5.5 6.2Tokyo 59.33 8.9 6.7 4.8Central 28.67 10.9 9.2 5.2Kansai 29.32 3.0 3.0 3.0Hokuriku 5.83 6.8 5.2 5.2Chugoku 12.54 10.9 10.5 12.9Shikoku 5.95 6.4 5.9 5.5Kyushu 16.59 3.0 3.1 8.7Average 178.27 7.3 6.3 5.8

1) Supply values are for the case of July.All data are calculated for the case of intense heat.

Data from Federation of Electric Power Companies (FEPC)

Safety of Nuclear Power Plantsin Japan

Safety1 (in general)

1. Safety is defined as the status where the risksof damage are in the allowable range.2. Some sort of risks exist at any time.3. It is required to clarify the possible risks.4. Risks which will cause destructive damagescannot be allowed even if their occurrenceprobability is quite low.

1) “Toward smooth supply of electricity after the Fukushima Daiichi NuclearPower Plant Accident”, Information, No.150, Eng. Acad. Jpn. (2011, inJapanese)

Establishing Safety1

• We have to know the fact that machines andapparatuses always deteriorate. Also, humanbeings will make some errors someday.

[Safety design for high‐risk systems]• fail-safe, fool-proof• fault-tolerance• multi-layered and independent control• passive safety-control (move toward safe-side at

any time)1) “Toward smooth supply of electricity after the Fukushima Daiichi Nuclear

Power Plant Accident”, Information, No.150, Eng. Acad. Jpn. (2011, inJapanese)

Safety of Nuclear Power Plant1 (in general)

1. We have to consider that accidents which werenot expected in initial design will occursomeday.

2. Probability of accident occurrence cannot bezero.

3. We cannot reach the true safety until we findmeasures to prevent from big accidents of lowprobability.

1) “Toward smooth supply of electricity after the Fukushima Daiichi NuclearPower Plant Accident”, Information, No.150, Eng. Acad. Jpn. (2011, inJapanese)

Problems of Fukushima Daiichi Nuclear Power Plant1

1. Geographical conditiona. Concentrated location

Only one substation for electric supply to4 reactors.

Ventilation towers are designed as common usefor two reactors.

b. Plant height from the sea level was insufficient.Prevention against tsunami wave was inadequate.

1) “Toward smooth supply of electricity after the Fukushima Daiichi NuclearPower Plant Accident”, Information, No.150, Eng. Acad. Jpn. (2011, inJapanese)

2. Problems in design and operation of  the Fukushima nuclear power plant1

a. Emergency power supply system was located inthe basement of the reactor building.

b. Prevention against hydrogen explosion was notsufficient.

c. Protection against natural disasters was notsufficient.

d. Emergency protection and information systemdid not work adequately.

1) “Toward smooth supply of electricity after the Fukushima Daiichi NuclearPower Plant Accident”, Information, No.150, Eng. Acad. Jpn. (2011, inJapanese)

Problems in design and operation of the Fukushima nuclear power plant (continued)

f. Measures and the standard of operation (SOP)to prevent severe accidents were not revisedfor a long time since they had been provided.Training and education of operators were notsufficient.

g. There were no targets for safety.h. Enthusiastic attitude in managing system to

keep good quality of electric supply was notsufficiently related to plant safety.

New Safety Standard by Japanese Nuclear Regulatory Commission 

1. Measures to prevent severe accidents are newly added. e.g.) prevention of diffusion of radioactive materials,

measures against terrorism, measures to prevent damage of fuel core and/or containment vessel, etc.

2. Reinforced items:Consideration to natural disasters and fireReliability of electric power supplyReactor cooling system

3. Improvement of the quality of earthquake- and tsunami-resistant facilities

Cost of nuclear power generationThe cost of nuclear electric power generation is discussed bymany people. (unit: yen/kWh, 1 yen = ca. 1 US cent)

Cheapest evaluation: 5~6Inst. Energy Eng. Jpn1: 7.2 (with back-end cost)K. Oshima2: 8.5 (without back-end cost)

Oshima claims that the cost will be 10.3 yen/kWh by addingthe research/development and location costs. He says that thecompensation cost of the accident will be 1.3 yen/kWh.However, if the cost of remediation of radioactive environmentis over 5 trillion yen3 (ca. 50 billion dollars), it will be ca. 174yen/kWh. Thus, my assumption is about 10 yen/kWh or more.

1. http://eneken.ieej.or.jp/4043.pdf2. Oshima,K.: “Cost of Nuclear Power Generation (in Japanese)”, Iwanami Publ. (2012)3. Nakanishi. J.: AIST report from NHK News (2013.7)

Possibilities of natural (renewable) energies

Development of natural  (or renewable) energy sources

Speed of the development of utilization ofnatural energy has been very slow in Japan.

Annual investment to utilization of naturalenergy in Japan is about 2000 yen (ca. 20 USdollars) per person, whereas that of China isabout $ 30 per person.

Japan’s national investment in this technologyaccounts for only 1~2% of that of the wholeworld.

Photovoltaics (PV, Solar cells)Key issues regarding PV are the efficiency of energyconversion and the cost of components (materials). Ifthe conversion efficiency becomes 20 % (now it isabout 15 %) and the equipment cost is below 2dollars/kWh, the cost generating electricity will be ca.20 yen/kWh (= 20 cents/kWh).The influence of the weather is significant for PV. Itdoes not work at night. Annual operation hours areonly 1000 h in Japan. However, the PV equipmentscan be installed on the rooftops of buildings or infallow fields. Therefore, the potential of the use ofPV is high.

WindmillsThe cost of generating electricity is lowerthan PV.The weather strongly affects the efficiency.The necessary installation area on the groundis relatively large. There are not manysuitable locations for windmills. Therefore,the oceanic windmill generator seems to bepromising.

Geothermal Electric Power Generation

• Japan has the third geothermal potential in theworld, although the present capacity ofgeothermal power generation is the sixth in theworld.

• Negotiation with hot spring business isnecessary.

• Cost depends on the location and the methodof boring.

Hydroelectric Power Generation

(middle or small scale)The generated power of a station of this kindis less than 30 MW and small.Construction of dams is unnecessary andthere are a lot of possible locations.Because the scale of the generators is small,the cost of the electricity is generally high.(large scale)Capacity can be increased by raising theexisting dam banks, which is promising.

Electric power generation using biomass

Since the biomass sources are located indispersed areas, collecting them becomescostly. The geographical range that truckscan collect biomass is said to be within 30km. Therefore, transportation cost is high.As power plants in this category is in smallscale, the cost of electricity becomes high.

Thermal power generationThermal power generation plays salient roles since most ofthe nuclear power plants have stopped operation.There is the problem of exhausting carbon dioxide. Therefore,the “carbon capture and storage” (CCS) process is desirable inthe future.Recent development of technology in this field is significant,such as “Integrated Gasification Combined Cycle (IGCC)”and “Advanced Ultra Supercritical (A-USC)” generation. Thegeneration efficiency will become over 46 % compared with40 % in case of the normal systems.Shale gas/oil is prospective in the near future. China andUSA have its enormous reserves. Although there isenvironmental concern in mining, shale gas/oil will contributeto reduce the cost of thermal power generation.

Costs and Potentials of Various Generation systems

Annual consumption in Japan: 1000 TWh/yIn average, 1000 TWh/y corresponds to 114 GW. Considering theefficiency of generation and the peak demand during the daytime, thecapacity should be more than this value. Let’s assume that 350 GWof the equipment capacity is needed. Then, natural energy sourcesexcluding PV can cover about 40 % of the demand.

Cost (yen/kWh) Potential (GW)Nuclear ca. 10 naThermal (coal) 6 - 7 naThermal (LPG) ca. 10 naSolar cell hopefully 20 naWind mills 11 - 26 25 (land) , 81(ocean)Geothermal same as above 24 (above 150C), 9.6 (53-150C)Hydrogeneration 10 - 36 3.7 (raising banks), 14 (others)Biomass 12 - 41 16Sum of potentials of natural energies except PV 146.3na = not applicable

Effect of energy savingEnergy savings play an important role to reduce electricityconsumption. In the spring of 2011 after the Fukushimaaccident the supply capacity was about 40 GW compared withthe original 60 GW in Tokyo Area (in the area covered by TokyoElectric Power, Inc.) The deficit could be covered by pumpedstorage hydro-generation, generation by independent powerproducers (IPP) and energy saving of community and individualcitizens. Altogether, ca. 50 GW was secured for electric supply.Some possible saving ways (ca. 5 GW in Tokyo area) are givenbelow:1. Change of lifestyle, Decrease in using lights and in running

elevators, escalators, trains, etc.2. Shift of working time and working sites (to avoid peak

demand)

Procedures to achieve stable supply of electrical energy

Japan has now surplus electrical energy without nuclear powergeneration by extensive operation of thermal power generation(Only two nuclear plants are in operation at this moment).It will be desirable if natural, reproducible energies are appliedmore widely.To promote the natural energies the FIT (Feed-in Tariff) systemhas been recently introduced in Japan. However, the prices ofelectricity of the present FIT seem to be quite high.In order to assure stable supply of electricity using the naturalenergies, preparation of social infrastructure such as powertransmit networks, development of rechargeable batteries, smartgrid systems is inevitable and should be accelerated.

Scenario of energy supply to achieve the low‐carbon society 

The operation of nuclear station (40 yearduration) will cease in 2049 if no new plant isconstructed. The substitution for nuclear energyis studied here with natural energy sources.

Case study on electric generation for 2020

Yamada, K.: Lecture given at the Club of Rome (October, 2011)

CaseAnnual Power Generation (TWh/y)

CO2 Emission (Mt/y)

Nuclear Thermal Hydro Natural incl. PV Total

1 270 580 80 70 1000 430

2 150 700 80 70 1000 510

3 0 850 80 70 1000 620

4 0 730 80 190 1000 540

5 0 570 80 350 1000 420

1. Case 1 is for 40 year duration of nuclear power plant.

2. Case 2 is for 30 year duration of nuclear power plant.

3. Cases 3-5 are for zero nuclear power..

4. Total CO2 emission in Japan in 1990 was 1141 Mt. Emission from electric generation in 1990 = 0.44 * 1141 = 502 Mt..

Summary1. Once a severe accident occurs in nuclear power plant, its

influence is enormous and the cost of resilience from thedamage is assessed to become tremendous amount.

2. Development of the use of natural energies should beaccelerated. More application of natural energies isdesirable. National policy is requisite to achieve this target.

3. It will be possible to establish the low-carbon society by2020 by introducing solar cells and other natural energies.The scenario to establish the “best mix” of energy sources isshown. In this context, effort of energy saving is effectiveand inevitable.

4. The modest life style is desired for the people in Japan.Since the population is decreasing, it is advised that theyshould be satisfied by moderate growth or stability of GDPper capita, not of gross GDP.

Thank you for your kind attention!