Superconducting wind turbine generators – A game changer?

Asger B. Abrahamsen, PhDSenior Research Scientist

HI2015Tuesday 22 September 2015

New innovations and Game changers session

DTU Wind Energy, Technical University of Denmark 20 September 2015

Motivation

2

2Power BI D l

1G : Copper + Iron

2G : R2Fe14B magnets + Fe

10 MW ~ 6 tons PM

3G : RBa2Cu3O6+x HTS + Fe

10 MW ~ 10 kg RBCO

IB

l

D

f

Torque

Fe

BR

R

TC = 93 K

Bc2 ~ 100 Tesla

J < 200 kA/mm2

TC = 583 K

Br ~ 1.4 Tesla

Fe

Cu

J ~ 2 A/mm2 TC = 1043 K

Br ~ 0 Tesla

TC = 39 K

Bc2 ~ 40 Tesla

J < 20 kA/mm2

DTU Wind Energy, Technical University of Denmark 20 September 2015

Choice of superconductors

Jensen, Mijatovic & Abrahamsen, J. Renewable Sustainable Energy 5, 023137 (2013)

MgB2 Columbus

1-4 €/m

20 €/m30 €/m

NbTi Bruker EST

0.4 €/m

4 m

m

Fill factor

~ 0.3 %

AmSC YBCO Bi-2223

DTU Wind Energy, Technical University of Denmark 20 September 20154

INNWIND.EU – 10 MW MgB2 SC Direct drive

• 10 MW reference turbine

D = 178 m & 9.7 rpm

• King-pin nacelle (DNV-GL)

• Two main bearings on hub

• Blade loads directly to tower

A.B Abrahamsen et. al., EWEA 2014

• Front mounted generator

- Easy to compare different types

• Scalable to 20 MW but issues with manufacturing (bearings and cast pieces)

• MgB2: T = 20 K by cooling machines

D = 6.0 m

L ~ 2.5 m

DTU Wind Energy, Technical University of Denmark 20 September 20155

10 MW generator optimization D = 6.0 m

Armature back

B [

T]

Armature Cu

Armature teeth

SC field

SC Pole

SC back

Fe: 3 €/kg MgB2: 4 €/m

Cu: 15 €/kg G10: 15 €/kg

PM: 50-75 €/kg

More iron

More

iro

n

DTU Wind Energy, Technical University of Denmark 20 September 20156

Active material cost: MgB2 from 4 €/m 1 €/m

Put as much iron as possible !

LMgB2 ~ 100 km assuming 1 €/m

€MgB2 ~ 100 k€

Matches Permanent Magnet Direct Drive

D. Liu et. al., submitted IJAEM

DTU Wind Energy, Technical University of Denmark 20 September 2015

Roadmap to 10 GW SCDD

Abrahamsen and Jensen , "Wind Energy Conversion System:

Technology and Trend“, ISBN 978-1-4471-2200-5, Springer 2012.

Wire use 10 MW(GW)

NbTi

720 km (Mm)

25000 km/year

fCAPEX ~ 2%

T = 4.2 K

MgB2

100 km (Mm)

5000 km/year

fCAPEX ~ 1-2%

T = 10-20 K

REBa2Cu3O6+x

200 km (Mm)

3000 km/year

fCAPEX ~ 40-50%

T = 20-40K

DTU Wind Energy, Technical University of Denmark 20 September 20158

ConclusionWhy superconducting?• Bairgap > 1 Tesla More compact direct drive for Multi-MW turbines with high torque• Vanishing dependency on Rare Earth element supply• High magnetic field vs. high current density High J most economical for MgB2 & HTS

• NbTi: T = 4.2K GE (transfer MRI to wind) CAPEX fraction ~ 2 %• MgB2: T = 20 K SUPRApower, Hypertech, AML, INNWIND CAPEX fraction ~ 1-2 % • YBCO: T = 20-40 K AMSC, (GE), ECOSWING, INNWIND CAPEX fraction ~ 40 %

• Chicken & egg: Demand to increase volume and drive down price of SC wires.• Huge learning potential for MgB2 and YBCO wires. Have to include wire improvement.

• Demonstrate MgB2 and YBCO field coil technologies.

Is it a game changer ? It is getting closer ….. But should we find a better material?

DTU Wind Energy, Technical University of Denmark 20 September 20159

H2S

• The smell of rotten eggs

• Freeze & Press (a lot)

• TC = 203 K *

• Hc2(0) 73 Tesla

• A BCS superconductor !!!!

• Light elements combined with Hydrogen. Better candidates?

• Cooling by liquid natural gas (LNG) at 111 K or -162 oC

*Drozdov et. al., Nature525, 73 (2015)Jensen et. al., J. Renewable Sustainable Energy 5, 023137 (2013)

DTU Wind Energy, Technical University of Denmark 20 September 201510

INNWIND.EU Collaborators in Workpackage 3 on Electromechanical Conversion

• Asger B. Abrahamsen (asab@dtu.dk)– DTU Wind Energy (DK)

• Dong Liu & Henk Polinder– Delft University of Technology (NL)

• Niklas Magnuson– SINTEF (N)

• Ewoud Stehouwer & Ben Hendriks-DNV GL (NL)

• Arwyn Thomas – Siemens Wind Power (DK)

Project website: www.innwind.eu