Rick Purcell
Associate Research
Mechanical Engineer
Curt Robbins
Assistant Research Engineer
Roger Jacobson
Research Professor
Kirk Collier
Collier Technologies
Alan Gertler
Research Professor
Overview
-There are over 10,000 off-grid location in Nevada requiring the use of electrical power at a cost of up to $500,000.
-Objective is to develop a cost-effective renewable Hydrogen based off-grid power system
-System will use renewable energy from photovoltaic, and wind turbines to charge a small battery bank and supply a PEM
electrolyzer to later be used in an Internal Combustion Engine.
60
3
Results
50
2.5
40
2
30
1.5
20
1
10
0.5
Power [kWe]
Power system is located in a trailer consisting of two 48 VDC to 120 VAC inverters,
twelve 12 VDC Gelled Electrolyte batteries, 600 cc/min PEM electrolyzer, fuel storage
for both hydrogen and propane, a 2 cylinder Lister Petter engine converted to run on
both hydrogen and propane, and 3 kWe 120 VAC generator at 1800 rpm. The system
os operated by a National Instruments Compact FieldPoint unit using LabView
software. The software allows the system to run 24/7 without human interface. An
energy flow chart below shows the operation of the trailer
Voltage [V]
System
0
8/2/2007
0:00
Test Locations
8/3/2007
0:00
8/4/2007
0:00
8/5/2007
0:00
8/6/2007
0:00
8/7/2007
0:00
0
8/8/2007
0:00
Time
Battery Voltage
Engine Power Output
Engine Operation from August 2nd to August 7th 2007
Field Test Site # 1
6.5 kW 24-hour Summer Load Profile
Residential house in Galena, NV in a arid
environment at the foot of Mount Rose.
Average winter daily electrical use of 21
kWhr/day. Power system connected to a 1.5
kWe bi-directional tracking solar array at 48
VDC
House at field test stie #1
Test Site #2
Power system located at DRI in Northern
Reno. A load bank produced an average
daily load of 6.5 kWhr/day. (based on offgrid locations averaging 5-12 kWhr/day).
System connected to a 1 kWe unidirectional tracking solar array. Additional
KOH electrolyzer powered by two 1.5 kWe
wind turbines and a 1 kWe uni-directional
tracking solar array.
Engine Operation
Item
Description
Quantity
Supplied Power (kW)
Carbureted engine designed to run off of either propane or
hydrogen. Propane is used as a back up when the hydrogen has
been consumed. The engine can handle loads up to 5 kWe on
propane and 2.4 kWe on hydrogen. For test site #1 the engine had
a turbocharger to improve efficiency. The exhaust gas was not
capable of producing enough pressure with the turbocharger so it
was removed for site #2. Site #2 also included separate spark
ingition timing and dwell settings for propane and hydrogen. The
chart above shows how often and for how long the engine ran and
test site #2. The chart below shows the engines efficiency on both
fuels.
Renewable Energy
Solar or Wind
3
3.00
Battery
12 VDC Gelled Electrolyte
12
1.3
Electrolyzer
Proton Energy HOGEN 600
2
H2 Storage
200 PSI storage tank 1 m^3
1
1 (.66 kg/day H2 in Summer)
90,000 BTU Hydrogen
Engine
ListerPetter 2 cylinder
Genset
1
3- Propane
2.5- Hydrogen
.32 kg/cycle, 1 cycle is 50
minutes, 2 cycles per day
Propane Backup
25 lb. Propane Tank
2
Power Output
The power system’s flow of energy follows
the chart to the right. Renewable energy
goes to the trailer directly into the inverter
units (acting as a bus bar) and is distributed
from there.
The electrolyzer will only
produce H2 when there is excess renewable
energy.
19
Solar Panels
Electrolyzer
ICE Generator
Efficiency %
Propane Tanks
Residential House
via Inverters
15
Propane
13
Accomplishments
11
A power system such as described is a feasible and cost-effective
means to solving the power requirements of an off-grid location.
7
-30 days of operation at Field Test site #1
5
Deka Photovoltaic
Gel Batteries
0.5
Direction of Energy Flow
Trailer Energy Flow
Safety
-Warning lights inside and outside of trailer to warn of high gas
levels in the air
9
48V Bus Bar
1,000,000 BTU
-Multiple fans with either continuous operation or controlled by
thermostat for ventilation
21
Hydrogen
Hydrogen Tanks
3 kW
-Gas detectors mounted on floor and ceiling with output connected
to operating system for automatic shutdown
BTU’s of Fuel
Test Site #2 Power system and KOH electrolyzer
H2
Power Consumption (kW)
To ensure the safety of the power system:
17
Energy Flow
Test Site #1 Solar array and trailer
The data from the trailer operation led to the following
requirements for a cost effective renewable based
hydrogen energy system. An off-grid location should
average 5-12 kWhr/day electrical consumption. Below
lists the necessary configuration so the power system
will only require the use of propane during days of
minimal renewable energy. The PEM electrolyzer
showed a production rate up to 560 cc/min at a power
consumption of 500 W. The hydrogen tanks can be
filled in 4-5 hours. The KOH electrolyzer produces as
much as 1 m3/hr which equates to .1 kg/hr and
capable of filling its tank in 9-10 hours.
1
1.5
2
2.5
3
3.5
Trailer Layout
-more than 100 continuous hours at Test site #2
Load [kW]
-over 100 hours of engine operation between hydrogen and propane
Engine Efficiency
-More than sufficient data on operation of power system
Hydrogen Power System for Remote
Applications
21
19
17
Efficiency %
Hydrogen
Test Sites
15
Propane
13
11
9
7
1. Residential field location at 21 kWhr/day
5
2. DRI facility at 6.5 kWhr/day
0.5
1
1.5
2
Load [kW]
6.5 kW 24-hour Summer Load Profile
Item
Description
Quantity
Supplied Power (kW)
Power Consumption (kW)
Renewable Energy
Solar or Wind
3
3.00
Battery
12 VDC Gelled Electrolyte
12
1.3
Electrolyzer
Proton Energy HOGEN 600
2
H2 Storage
200 PSI storage tank 1 m^3
1
1 (.66 kg/day H2 in Summer)
90,000 BTU Hydrogen
Engine
ListerPetter 2 cylinder
Genset
1
3- Propane
2.5- Hydrogen
.32 kg/cycle, 1 cycle is 50
minutes, 2 cycles per day
Propane Backup
25 lb. Propane Tank
2
3 kW
1,000,000 BTU
2.5
3
3.5