CC-124 Growth Kinetics (Light Intensity Results)

Bojan Tamburic

20/10/2009

Raw Data – pH and OD

Raw Data – OD and pO2

Logistic (Sigmoid) Fit for OD

)tr(t 0e1

KOD(t)

K is the maximum attainable ODr is the growth rate

Minimise total least squared error of r and t0

Recover K by linear optimisation

Processed OD Data

Update on Technico-Economic Modelling

Phil Grünewald

Solar Hydrogen

The Value of Saving Sunshine for a Rainy Day

PHIL GRÜNEWALD

Does PEC make economic

sense ?

SUN HYDROGEN ECONOMICS

1. How to model a PEC device?2. Which parameters matter?3. What configuration is best?4. How does PEC compare to alternatives?

OBJECTIVES

Centralised Decentralised

InfrastructureLarge investmentSupply demand – Catch22

Small scale build upContinues low C CHPDemonstration projects

- +++

--

Infrastructure

The trouble with the sun• Irradiation not on demand• Poor temporal correlation with demand• PV / solar thermal don’t displace generation capacity

???Can H2 storage

help?

Irrad

iatio

n

Dem

and

24h 24h

Source: storedsolar.com

Solar energy can be stored as H2

Either - by electrolysing PVOr directly-photo-electrochemically

Or in - Batteries and - Thermal Storage

Alternatives…

A residential model

Model Output

Electrical demand (2.97 MWh)

Thermal demand (12.83 MWh)

Grid68%

Solar7%

Hydrogen21%

Stored4%

Grid53%

Solar23%

Hydrogen24%

Cashflow

-1

-0.5

0

0.5

1

1.5

2

2.5

0 5 10 15 20

Annual saving

Cashflow

Years

k£

Displaced demandDisplaced demand

Efficiency matters…

0

200

400

600

800

1000

1200

8% 10% 12% 14% 16% 18% 20%

PVSTPECMix

10 12 14 16 18 . .

1200

1400

800

600

400

200

0 .

20 24 28 32 36

ηPV, PEC

ηST

Conversion efficiency [%]

NP

V [

£]

10% PEC module: ~32 £ m-2

12% PEC module: ~41 £ m-2

(excl. storage cost)

Value of storage

900

950

1000

1050

1100

1150

1200

1250

1300

1350

1400

0 1 2 3 4 5 6 7 8 9 10

0 kWh

1.5 kWh

3 kWh

4.5 kWh

6 kWh

Hydrogen Storage Capacity [kWh]

NP

V [

£]

Thermal storage

900

950

1000

1050

1100

1150

1200

1250

1300

1350

1400

0 1 2 3 4 5 6 7 8 9 10

0 kWh

1.5 kWh

3 kWh

4.5 kWh

6 kWh

• High marginal value for small amounts of H2 storage• H2 displaces thermal storage for larger capacities

1 2 3 4 5 6 7 8 9 10

20m^20

500

1000

1500

2000

250020m^240m^260m^280m^2100m^2

The Mix Makes the Magic!

2

2

2

2

2

1 2 3 4 5 6 7 8 9 10

20m^20

500

1000

1500

2000

2500

1 2 3 4 5 6 7 8 9 10

20m^20

500

1000

1500

2000

2500

1 2 3 4 5 6 7 8 9 10

20m^20

500

1000

1500

2000

2500

2

PV PEC ST

Ener

gy V

alue

[£]

all 3

• No gain form PV and Solar Thermal beyond 20m2

• PV highest “energy value” for small installations(Note: costs are excluded)

Peak Hydrogen Storage [kWh]

0

0.5

1

1.5

2

2.5

3

3.5

Ap

r

Jul

Oct

Jan

Ma

yJu

n

Au

gS

ep

No

vD

ec

Fe

bM

ar

2 -

3 -

4 -

1 -

0 -P

ea

k H

2 S

tora

ge

[kW

h]

1 2 3 4 5 6 7 8 9 10

20m^20

500

1000

1500

2000

250020m^240m^260m^280m^2100m^2

The Mix Makes the Magic!

2

2

2

2

2

1 2 3 4 5 6 7 8 9 10

20m^20

500

1000

1500

2000

2500

1 2 3 4 5 6 7 8 9 10

20m^20

500

1000

1500

2000

2500

1 2 3 4 5 6 7 8 9 10

20m^20

500

1000

1500

2000

2500

2

PV PEC ST

Ener

gy V

alue

[£]

all 3

• Best results from combination of routes

100 m2

H2 storage peak: 6 MWh

20 m2

H2 storage peak: 6 kWh

24 £ m-2

Conclusion

• Generating and storing hydrogen can only be economical from excess energy

• Installations need to be big or• Use electrolytic H2 from low-carbon grid electricity

• Best results come from a mix of electricity, heat and hydrogen generation

• Poly-generation configurations should be considered

Summary

• In order to “save”, large installations are required• Best results with a mix of PV ST and PEC• Efficiency is worth ~4 £ %-1 m-2 (*)

• Demand for domestic scale solar storage is small

(*) given a long list of assumptions…

Thank you.Thank you.Thank you.Thank you.

The trouble with (average) humans

24h

kWh

5min

-1

Data: Courtesy of Adam Hawkes24h

30 days of one month 1 day (high and low res.)

Temporal resolutionThe drawback of limited ramping and finite power rating is only revealed with high temporal resolution data!

The drawback of limited ramping and finite power rating is only revealed with high temporal resolution data!

18%

8%

Lamp calibration

Steve Dennison

Lamp Calibration: 19/20th October

0.000

0.050

0.100

0.150

0.200

300 400 500 600 700 800

Wavelength / nm

Irra

dia

nce

/ W

m-2

Lamp Calibration: 19/20th October

0.000

0.010

0.020

0.030

0.040

0.050

250 300 350 400 450 500 550 600 650 700 750

Wavelength / nm

Irra

dia

nce

/ W

m-2

300 nm 350 nm 400 nm 450 nm 500 nm 550 nm 600 nm 650 nm 700 nm

FZ

• upgrading the Sartorius system:

• Instrumentation: update on various H2 sensors

Prices:sensor only £920Replacement tip = 600Readout unit: MS 08 £2900

There are issues with dimensions:OD= 17mmsartorius insert ID = 19mm

AMT Analysenmesstechnik H2 sensor : detection: amperometric

Quantitech/ H2Scan H2 sensor

Detection: solid-state Pd-Ni based sensors

sensor components : (i) metal insulator semi-conductor: detects H2 atoms as a charge at the interface of Pd and dielectric material(ii) a thin film resistor responds to increase in H2 uptake/ lattice Pd lattice/ incr. scattering sites for electrons

H2 concentration from 15ppm – 100%

Prices:Hand held Leak detector: Model 500 £2,725

AREA MONITORS £1850 -£4995

HY-OPTIMA :In-Line Hydrogen in Air Process Monitor Models 700, 720, 730 £3450, £4,340, £4895 respectively