Onboard Compressed Hydrogen Storage: fast filling

IA HySafe and JRC IET Workshop

Research Priorities and Knowledge Gaps in Hydrogen Safety

16-17 October 2012, Berlin, Germany.

P. Moretto, B. Acosta-Iborra, D. Baraldi

M.C. Galassi, N. De Miguel, R. Ortiz Cebolla

Institute for Energy and Transport, JRC/EC, Netherlands

0 5 10 15 20 250

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Vo

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[kg

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Gravimetric density

[100*kgHydrogen

/kgsystem

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Storage Technology

Type IV tank

Steel tank

Theoretical cylindrical tanks (increasing pressure)

commercial tanks

Target

Liquid H2

[%]

The RCS Status

• Regulations

� Commission Regulation (EU) No 406/2010

� JARI is updating the Japanese regulation

• International effort for regulations (UN-ECE)

�Global Technical Regulation for Hydrogen Fuelled

Vehicles (GTR HFV) 2012 – under approval

Requirements to qualify hydrogen storage

systems for on-road passenger vehicles

• International standards

�SAE-J2579 Technical Information Report for Fuel

Systems in Fuel Cell and Other Hydrogen

Vehicles

� ISO/TS 15869:2009 Gaseous hydrogen and

hydrogen blends -- Land vehicle fuel tanks

Car–RefuellingStations Interface

• It considers different types of refuelling stations:

� Type “A”- Station has -40 ̊ C pre-cooling

� Type “B”- Station has -20 ̊ C pre-cooling

� Type “C”- Station has 0 ̊ C pre-cooling

� Type “D”- Station has no pre-cooling

• …and 2 different type of re-fuelling protocols:

� Non-communication between the vehicle and the re-fuelling station (only pressure and ambient/external T)

� Communication e.g. including also T inside the tank

SAE protocol J2601: Fueling Protocols for Light Duty gaseous Hydrogen surface Vehicles, March 2010

The refuelling of a hydrogen car/bus with compressed hydrogen tank has to take place in approximately 3 minutes ���� 5 to 20 g/s!

This industrial requirement has been defined by comparison with fillings times for other fuels. (In other words, on assumption on the average patience of a driver at a filling station).

From material and safety considerations point of view however, the maximal temperature in the tank cannot exceed 85°°°°C, so that pre-cooling of hydrogen is required in many cases.

Fast Filling

Refuelling: technological – fundamental questions to improve process

How to measure the mass flow rate with the required accuracy in the re-fuelling station? (metering issue: the bill for consumers!)

The requirement to pre-cool hydrogen is lowering process efficiency and it increases system costs: are there alternatives?

The criterion of < 85°°°°C: is it valid for local, short time events? How is the degradation of the properties material under these conditions? How conservative is the criterion?

Fast Filling

Pneumatic test

Time

Pmin

Typically 20 bars

Pmax

Typically nominal

pressure

Fuelling timemax 3 or 5 minutes

Holding timetypically 0 - 30 min

Defuelling timetypically 0.5 – 1 hr

Gap between cycles

Pressure

Experiments Full cycle

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Time (min)

Bar

-20

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Pressure

Internal T5

T Boss

T Bottom

Experiments

The filling phase with and without pre-cooling (Hydrogen)

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Time (min)

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-20

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T gas without pre-cooling (pos 5)

Pressure

T gas with pre-cooling (pos 5)

TC5 TC3

TC4

TC3

TC4

TC2

TC1

TC2

TC1

TC6 TC6

TEXT 1

TEXT 3

TEXT 2

Experiment:

1.2-722 bar

filling time 245s and 330 s

Tgas=Tamb=294K (21ºC)

CFD Validation

100s

Comparison between simulation and experiment

Temperature Distribution - top

270

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0 50 100 150 200 250

t [s]

T [K

]

TC4 exp

TC4

4

Temperature Distribution - bottom

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t [s]

T [K

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TC2 exp

TC2

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TC5 TC3

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TC3

TC4

TC2

TC1

TC2

TC1

TC6 TC6

TEXT 1

TEXT 3

TEXT 2

CFD Validation

Maximum Temperature

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TC1

TC2

TC3

TC4

TC5

TC6

TCs Position

T [

C]

0.00

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err

[%

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exp

calc

err

Results: Maximum temperatures at

the end of the filling procedure

Maximum Temperature

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TC1

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TCs Position

T [

C]

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2.00

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err

[%

]exp

calc

err

Maximum Temperature

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TC1

TC2

TC3

TC4

TC5

TC6

TCs Position

T [

C]

0.00

2.00

4.00

6.00

8.00

10.00

err

[%

]

exp

calc

err

Test H2 10122010

Test H2 25022010

Pos1

Pos1

CFD Validation

Simulations Mass flow rate effect

Calculation with pre-cooling

CFD validation with broader range of conditions e.g. initial conditions,

pre-cooling, different tank size and geometry.

Development and validation of accurate engineering correlations that

can be applied in re-fuelling stations.

Accurate measurement of mass flow rate.

Filling strategy that can work without pre-cooling or with minimum

use of pre-cooling.

Are 85°C too conservative?

Some Fast Filling Gaps

References

1. SAE J2579 Technical Information Report for Fuel Systems in Fuel Cell and other Hydrogen Vehicles, SAE International, Issue 2008.

2. ISO/CD 15869-Gaseous hydrogen and hydrogen blends – Land vehicle fuel tanks, ISO 2001.

3. Commission Regulation (EU) No 406/2010 of 26 April 2010 implementing regulation (EC) No 79/2009 on type-approval of hydrogen-powered motor vehicles. Off J EurUnion 18.05.2010. L 122/1e107.

4. UN ECE WP.29 GRSP, Informal Group on Hydrogen and Fuel Cell Vehicles - Sub group safety (HFCV-SGS), Draft GTR on Hydrogen Fuelled Vehicles, February 2011.

1. Acosta B., Moretto P., Frischauf N., Harskamp F., GASTEF: The JRC-IE Compressed Hydrogen Gas Tanks Testing Facility, Proceedings of the Eighteenth World Hydrogen Energy Conference, 16-21 May 2010, Essen.

2. Acosta B., Moretto P., Frischauf N., Harskamp F., Bonato C., Fast Filling and Permeation Experiments at the JRC-IE GasTeF Facility, Proceedings of the Fourth International Conference on Hydrogen Safety, 12-14 September 2011, San Francisco.

3. Galassi M.C., et al., Validation of CFD Models for Hydrogen Fast Filling Simulations,

Proceedings of the Fourth International Conference on Hydrogen Safety, 12-14 September 2011, San Francisco.

4. Galassi M.C. et al., CFD analysis of fast filling scenarios for 70 MPa hydrogen type IV tanks, International Journal of Hydrogen Energy, 37 (2012), 6886–6892.