BIG energy from SMALL power hydro electricity systems
Phil Hofmeyer, Ph.D. Morrisville State College’s
Renewable Energy Training Center
July 5-7, 2013, Lake Placid, NY
Overview
System components
Resource assessment
Estimating power and energy
Example systems
Permitting Process
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Grid-interactive
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• No battery cost
• Smaller inverter
• Lower wire costTurbine
Fused AC
Disconnect
Diversion
Controller
Diversion
load
Inverter
kWh
meter
Main
panel
Estimating output
• Unlike wind and solar, if sized appropriately, hydro power can be nearly constant production
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(GPM) Flow x (feet) Head(Watts)Power
Estimating power – an example
• Stream with 100 feet of head and 100 GPM of available flow
• Power = (100*100) / 10
• Power = 1000 Watts (or 1 kW)
– Relatively low power
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Estimating Energy – an example
• Assuming 1,000 W continuous
• 2% annual downtime for maintenance
• Power x Time = Energy
• 1 kW * 8760 hrs/yr * 0.98 = 8580 kWh/yr
Is that good?
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Is that good?
• To get equivalent energy from a wind system would require ~15’ wind turbine rotor (or larger)
• …or ~7 kW solar array in central NY (>550 ft2 of collector area, or more)
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Some other examples
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80 GPM on 75 feet of head
610 W, 5020 kWh/yr120 GPM on 40 feet of head
480 W, 4000 kWh/yr
Some other examples
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450 GPM on 90 feet of head
3.5 kW, 30,000 kWh/yr250 GPM on 120 feet of head
3 kW, 25,000 kWh/yr
System economics – An example
• 450 GPM, 90’ head, 3.5 kW power
• 1300’ of 6” polyethylene penstock
• Turbine, inverter, controller, etc.
• System cost: $35,000
• Expected lifespan: 20 years
• Annual energy output: 33,500 kWh
• Energy rate of $0.13/kWh
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System economics – An example
• System cost: $35,000 (no incentives available)
• $0.13/kWh * 33,500 kWh/yr = $4,355/yr
• Simple payback: 35,000/4,355 = ~8 years
• Return on Investment: 12.5%
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Conclusions
• Small power systems lead to cost-effective energy production
• NEED for NYSERDA incentives (much more energy returned/dollar invested)
• DEC permitting often required
– Very good relationships thus far!
• Highly selective sites and clients
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Thank you!
Phil Hofmeyer, Ph.D.
Assistant Professor of Renewable Energy
Morrisville State College