advances in onsite hydrogen generation for upper air observations wmo technical conference on...
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ADVANCES IN ONSITE HYDROGEN GENERATION FOR UPPER AIR OBSERVATIONS
WMO TECHNICAL CONFERENCE ON METEOROLOGICAL AND ENVIRONMENTAL INSTRUMENTS AND METHODS OF
OBSERVATIONHelsinki, Finland, 30 August – 1 September 2010
Prepared and Presented byProton Energy Systems
Upper Air Observations
• Radiosondes are sensor packages attached to weather balloons that are filled with helium or hydrogen gas
• The radiosonde generally consists of a radio transmitter, GPS receiver, temperature sensor (thermistor), humidity sensor, and sometimes a pressure sensor
• A complete vertical profile of temperature, humidity, wind speed and wind direction in the vicinity of the launch station can be obtained during its two hour sounding to nearly 100,000 feet up into the atmosphere
Lift Gas Use and Methods• Helium
– Delivery of pressurized cylinders is only option– Scarce outside of U.S.A.– Expensive (and getting more expensive)– Pressurized cylinders pose logistical and safety concerns
• Hydrogen– Delivery of pressurized cylinders
• Expensive, poses logistical difficulties and safety concerns– On-site production through chemical reaction
• Dangerous to personnel and the environment• Logistical difficulties and limitations on amount of gas produced
– On-site production through electrolysis• Liquid electrolyte
– Hazardous materials used, high maintenance, large footprint– Dangerous to personnel and the environment
• Solid polymer electrolyte– No hazardous materials used, safe for personnel and the environment, easy to
install and maintain, small footprint
On-site Hydrogen GenerationElectrolysis of Water Utilizing KOH, circa 1800:
2H2O(l) → 2H2(g) + O2(g)
Hydrogen gas (H22) forms at ) forms at cathodecathode
Oxygen gas (O22) forms at ) forms at
anodeanode
William Nicholson, ca. 1812Engraving by T. Blood after a portrait painted by Samuel
Drummond (1765-1844)
Effect first discovered by Effect first discovered by William Nicholson, English chemist
On-site Hydrogen GenerationSo What is KOH Electrolysis?
• Electrochemical Process that uses a liquid electrolyte of KOH (potassium hydroxide)
• Hazardous Chemicals are used
• Produces Hydrogen and Oxygen from Electricity and Water
• Must maintain a balanced pressure between hydrogen and oxygen
• Limited start and stop times
On-site Hydrogen Generation
Initial PEM innovatorsGrubb & Neidrach, GE Research, 1955
PEM ElectrolysisPEM Electrolysis
Cathode+ -Anode
e-
e-
e-
O
e-
Power Supply
Solid ElectrolyteProton Exchange Membrane
+ +
O
e-
e-
e-
Oxygen
++++
+ +
FFFFFF
SO3HSO3H
C
F
C
O
C
F
C
F
C
O
C
F
Rf
Rf +H
H
HH
Water
e-
e-
H
H
O
PEM Fuel CellPEM Fuel Cell
Anode+ -Cathode
e-
e-
e-
e-
Electric load
Solid ElectrolyteProton Exchange Membrane
+ +
e-
e-
e-
Hydrogen
Oxygen
++++
+ +
FFFFFF
SO3HSO3H
C
F
C
O
C
F
C
F
C
O
C
F
Rf
Rf +H
H
HH
e-
e-
Water
H
H
O
O
O
PEM ElectrolysisPEM Electrolysis
Cathode+ -Anode
e-
e-
e-
O
e-
Power Supply
Solid ElectrolyteProton Exchange Membrane
+ +
O
e-
e-
e-
Oxygen
++++
+ +
FFFFFF
SO3HSO3H
C
F
C
O
C
F
C
F
C
O
C
F
Rf
Rf +H
H
HH
Water
e-
e-
H
H
O
Cathode+ -Anode
e-
e-
e-
O
e-
Power Supply
Solid ElectrolyteProton Exchange Membrane
Solid ElectrolyteProton Exchange Membrane
++ ++
O
e-
e-
e-
Oxygen
++++++++
++ ++
FFFFFF
SO3HSO3H
C
F
C
O
C
F
C
F
C
O
C
F
RfRf
RfRf ++H
HHH
HH
HHHH
HH
Water
e-
e-
HH
HH
O
PEM Fuel CellPEM Fuel Cell
Anode+ -Cathode
e-
e-
e-
e-
Electric load
Solid ElectrolyteProton Exchange Membrane
+ +
e-
e-
e-
Hydrogen
Oxygen
++++
+ +
FFFFFF
SO3HSO3H
C
F
C
O
C
F
C
F
C
O
C
F
Rf
Rf +H
H
HH
e-
e-
Water
H
H
O
O
O
PEM Fuel CellPEM Fuel Cell
Anode+ -Cathode
e-
e-
e-
e-
Electric load
Solid ElectrolyteProton Exchange Membrane
Solid ElectrolyteProton Exchange Membrane
++ ++
e-
e-
e-
Hydrogen
Oxygen
++++++++
++ ++
FFFFFF
SO3HSO3H
C
F
C
O
C
F
C
F
C
O
C
F
RfRf
RfRf ++H
HHH
HH
HHHH
HH
e-
e-
Water
HH
H
O
O
O
O
O
Electrolysis of Water Utilizing PEM:
On-site Hydrogen GenerationSo What is PEM Electrolysis?
• Electrochemical Process that uses a solid electrolyte
• Zero Hazardous Chemicals or Emissions
• Produces Hydrogen and Oxygen from Electricity and Water
• High Pressure without mechanical compressors
• Very fast start and response times
On-site Hydrogen GenerationversusPEM
No hazardous materials or chemicals required– Contains high purity water only– Long component life– Safe for operators and service
technicians– Easy to maintain and service, no
caustic solution to drain and refill Low Maintenance
– Typical maintenance less than 4 hours per year
– Any repair can be completed in 1 hour or less
KOH
Hazardous Caustic chemicals required– Corrosive to components– Possible asbestos content- known
carcinogen and banned in many countries
– Eye and skin hazard. Extreme caution required in handling
– Special purification equipment required
– Overboard discharges possible with expensive damage to downstream components
High Maintenance– Some require 40+ hours of
maintenance per year and increases as corrosion damages components
– Process component repair may require draining of caustic and extensive downtime
PEM vs KOH InstallationTypical Bi-Polar KOH Hydrogen Plant Layout and Equipment
Inflating Bed
Hydrogen G
enerator
Tank
Electrolyzer
Tank
PEM vs KOH InstallationTypical Bi-Polar PEM Hydrogen Plant Layout and Equipment
Inflating Bed
Hydrogen G
enerator
Tank
Electrolyzer, water system and tank
On-site PEM Hydrogen Generation• Summary of demonstrated PEM improvements
to upper air operations– Safer
• No hazardous chemicals required (safer for both personnel and the environment)
• High differential hydrogen pressure (safety concerns-explosion and fire- of hydrogen/oxygen mixing are removed)
• Mechanical compressor is eliminated– Smaller physical footprint– Fully integrated design
• Rectifier, purification and electrolyzer in one cabinet– Easier to maintain– Higher reliability
Upper Air ObservatoryPEM Electrolyzer Installations