OTEC power, research and implementation by the Korean Government: Case study of a 1MW power

plant for the Republic of Kiribati

Hyeon-Ju Kim, Ho-Saeng Lee, Dong-Ho Jung, Sung Woo Kim,

Sa-Young Hong and Christopher Mark Day

Korea Research Institute of Ships and Ocean Engineering (KRISO)

Ministry of Oceans and Fisheries(MOF) of Republic of Korea

1. OTEC history and current status

2015 : 100kW

OTEC plant

Grid-connected

(NELHA/MOE)

22kWIn 1927

http://www.makai.com/ocean-thermal-energy-conversion/

Ongoing project for OTEC demonstration

Goseong, South Korea

20kilowatt plant, Korea(MOF)

(only operated in the summer)

Tarawa, Kiribati (by KRISO team)

1 megawatt plant, Korea(MOF) Martinique, Fr(by Akuo E.)

10 megawatt plant, EU

Electric power can be generated by rotating a turbine using

gaseous flow of evaporated working fluid. Warm surface and

cold deep seawaters are used for heat source and sink,

respectively.

2. 1MW OTEC plant design

100kW-OTEC(USA‘15)50kW-OTEC(Japan‘13)15kW-OTEC(French‘11) 20kW-OTEC(Korea‘13)

Pump

Turbine

Evaporator

Condenser4

1 2

3

Surface sea water

Deep seawater

2

34

1

S

T

Qe

Qc

WT

WP

Working fluid : R32 refrigerant

Analysis of 20kW OTEC for 1MW design

93.1%/1MW

87.5%/1MW

90.0%/1MW

80.0%/1MW

Seawater

Pump

Condenser

Evaporator

Turbine-generator

Accumulator

Receiver

WF pump

Design of 20kW OTEC plant as 1MW pilot plant

20kW OTEC pilot plantCondenser

Evaporator

Turbine-generator

ReceiverCirculation pump

Separator

Fabrication of pilot OTEC plant for 1MW

Experiment of 20kW OTEC pilot plantOperation of 20kW OTEC

https://www.facebook.com/pg/OTECUT/videos/?ref=page_internal

Detail design of 1MW OTEC plant on offshore platform and land

ESCAPE

TRUNK

ELE

C. W

ELD

ING

RM

45000

45000

Ref.

Recovery

Rec

over

y Tan

k

EXPANDED METAL

WORKSHOP &

STORE

P

P

P

P

HULL

DUCT

700C

ESCAPE TRUNK

B.W

B.W

B.W

MAIN

SW

ITCH B

OARD

Va

cuum

PLA

NT

NO

RT

H

PLANT EAST

PLA

NT

SO

UT

H

PLANT WEST

On-land OTECOffshore OTEC

SWACAgri/aquaculture

Desalination Byproducts

2020~2025

(M-ODA/?)

2016~2020

(M-ODA/Kr)

3. 1MW OTEC structure design

1MW – ID 1.2m HDPE / 10MW – ID 4m FRP / 100MW – ID 10m FRP

* Wire ; Reinforcement by tensile strength

* Lumped mass ; For Specific density

Design condition of 1MW OTEC plant

Water depth: 1100m

◇ Environmental conditions (Tarawa, Kiribati)

Current velocity: 1.4m/s100yr Storm case Max. Current case

Hs (m) 3.89 (~10.2) 1.49

Tp (sec) 14.0 (~12.8) 14.0

Gamma of

JONSWAP Spectrum2 6

Mean wind speed for

10 min. (m/s)28.4 (~33.80) 8.00

Current

speed

(m/sec)

Surface 1.40 0.91

50m 0.49 0.79

100m 0.30 0.79

150m 0.30 0.79

350m 0.21 0.30

800m 0.21 0.30

1000m 0.21 0.30

Example of current profile at Tarawa waters

100yr storm Wave spectrum

* ( ) : external force environment around Fiji

Bottom topography (SPC)

Design of offshore platform for 1 MW OTEC plant

Stability enhancement of floater

Type BType A

PitchHeave

Model test in regular waves

OTEC A

OTEC B

Model test in irregular waves

Hs=10.2mTp=12.8s

Dynamic response test w & w/o riser

Type BType A

Fatigue analysis of OTEC riser

Structural analysis of OST OTEC platform

Analysis and design of mooring systemsand subsea power cable

2nd deck

Design of 1 MW OTEC plant

3rd deckTop deck

Approval In Principle from BV

Assembling

Verification experiment

1MW OTEC demonstration plant Performance test and transport to install

For multi-purpose use of discharged

seawater for FEW applicationDesign approval of 1/10MW OTEC plant

on offshore platform will be tried in 2020

South Tarawa

(2018)

(2018~2019)

2222

SustainableSeawaterUtilizationAcademy

ODA projects often fail at the point ofownership transference

We need detailed program for full technology transference

A competent capacity-program designed and installed with local stakeholders

Who&What

1MW OTECDemonstration

PlantCapacity-building for

operation and maintenance by Kiribati people

2525

Kiribati

Goseong, South Korea

20kilowatt plant, Korea(MOF)

(only operated in the summer)

Tarawa, Kiribati (by KRISO team)

1 megawatt plant, Korea(MOF)

2626

0

10000

20000

30000

40000

50000

Kiribati Netherlands South Korea USA

Electricity and GDP

Electricity use per capita (kWh per capita) GDP - per capita (USD)

2727

0

10

20

30

40

50

60

70

80

90

100

Kiribati Netherlands South Korea USA

Obseity and Water

Obseity - adult prevalence rate (%)

Water (Population with improved drinking water sources -urban and rural)

2828

1

100

10,000

1,000,000

100,000,000

Kiribati Netherlands South Korea USA

Arable land and Climate change

Arable land (Hectares) CO2 emissions (Kt)

Our goal

Self-Reliant for Food, Energy, and Water

0

5

10

15

20

25

30

35

Kiribati (2013) Future Kiribati

CO2 emissions (Kt)

0

10

20

30

40

50

60

70

80

90

Obseity prevalence (%) Water availability (%)

Food and water

Kiribati (2013) Future Kiribati

0

2000

4000

6000

8000

10000

Electricity use per

capita (kWh per

capita)

Arable land

(Hectares)

GDP - per capita

(USD)

Electricity, Agriculture, and GDP

Kiribati (2013) Future Kiribati

How and when?

2016Design and

fabrication of essential

parts

2017Design and fabrication

of secondary parts

2018Installation and test

operation in the East Sea

of South Korea

2019~2021Transportation,

installation and test

operation in Tarawa, Kiribati

SSUAInvitation of 2

SSUA participants to South Korea

Advanced courses

Education center for

seawater plant

1MW OTECDemonstrati

on Plant

Preparation for

technology transference

Prof. AhmedUSPOTEC Prof. Albert Kim

UHMDesalination

Prof. N’YeurtUSP

Bioenergy

Prof. J. K. KimCheonnam

Uni.Marine survey Dr. H. S. Lee

KRISOOTEC

Prof. K. H. KimChungnam Uni.Water Quality

Prof. NuttallUSP

Logistics/Finance

Prof. S. G. Jeon

HangyangUni.

Finance

Director Yoon

SeabaseDiving

Dr. H. J. KimKRISO

Program Manager

OTEC/DOWA

Dr. D. S. MoonKRISO

Desalination

Mark Day

SPCCoastal

construction

Jeremy HillsUSPODA

program

Prof. H. G. KimGangneung-Wonju Uni.Seaweed

Prof. W. H. Kang

Kangwon Uni.Agriculture

Prof. ChoiKorea Uni.Eco-Toilet

Prof. MichaelnaUSC

Renewable Energy and

Entrepreneurship

KRISO CoordinatorS. W. Kim

USP CoordinatorM. Toginga

Honorary Advisor(FP, Kiribati) A. Tong

Most importantly, Our SSUA participants..

1MW OTEC demonstration plant Installation for long term operation (2019~2020)

On-land OTEC

2016~2020/MOFOffshore OTEC

2020~2025

SWAC

Agri/aquaculture

Desalination

Power supply and cascade utilizationbased on 1MW OTEC plant operation

On-land OTEC

2016~2020/MOFOffshore OTEC

2020~2025

SWAC

Agri/aquaculture

Desalination

37

Thank you for your attention!