Red Bank Hydro initial test run

Nearly four years after the inception of this monumental project, on Friday, February 8, 2008 Simon opened the turbine, and when the RPMs hit 150, instructed Joel to energize the first motor/generator--sending electricity back into the grid for Red Bank Hydros first (unofficial) kilowatt-hour of production. We even made the meter run backwards for 2 kwh; too bad it was not an old-style, mechanical meter--would have been a better visual!

Stats:
*64 acre lake
*40 cf/s average water flow, 10 ft. head
*50 hp Francis turbine (refurbished 1960's era)
*150 RPM (1750 ft/lbs calculated torque)
*600 RPM at secondary shaft
*1760 RPM motor/generators
*each induction motor/generator: 15 hp, single phase, 230 VAC
*peak power for test run: 40 amps (9600 VA)
*eventual peak power generation: 24 kilowatts
(sorry for the imperial units ;-)

Kids, don't try this at home! It is dangerous to run this kind of equipment without proper mechanical guards and electrical safety circuits.

Category:

Science & Technology

Tags:

• red
• bank
• micro
• hydro
• distributed
• generation
• hydroelectric
• induction
• generator
• green
• power
• renewable
• water
• energy

[bogdanp9]

This may be a stupid question but can the wall that the motors are mounted on cope with the vibrations ?

[joel4692]

It is an 8 inch, solid concrete wall...not an issue.

[74VDC]

1) At what RPM are the induction motors turning? 2) What is their nameplate operating RPM? 1750? 3) What was the nameplate current rating of those motors at 220V. when operated as motors? 4) Did you have any permitting trouble? 5) What is your head and flow? 6) What type of turbine runner do you have and where did you find it? 7) Do you have enough volume to operate continuously...year 'round? 8) What state are you in and do they have net-metering, and if so, are you grid tied?

[joel4692]

Nameplate RPM = 1760, which means 600 RPM at secondary shaft...generally that tachs out at 605-610, but I don't know if the motors are actually spinning faster than 1760.

Nameplate voltage = 230 (actually closer to 240 here) Amps = 60, but that's really for circuit breaker sizing.

No permitting problems as such, tooke a while to convince the utility that there was no chance of generating power when grid was down.

[RickMHobson]

Are those induction -motors- you are using for generators? WHat kind, if any, modifications did you have to make to them specifically, to use them in this context? Very cool :D

[joel4692]

Yes, ordinary induction motors, no modifications. By putting forward pressure on them, they generate instead of consume electricity. Actually, I did disconnect the "B phase" (starting) coil (found large single phase motors.)

[montecarlo11111]

kerwick hotel all day baby!!!!!!!

[taylortownmayor]

If the nameplate is 1760 rpm you have a 4 pole motor and a synchronous speed of 1800 rpm. To actually generate you have to spin the motor faster than synchronous speed. Getting it to its nameplate current would require you to get up to 1840 or so rpm. You're pushing watts back out of the system but the utility provides VARS to excite the motor. For a residence utilities only meter watts so you don't get charged for the VARS.

This is the best setup I've seen!!!

[Hornj21]

Nice setup. As a microhydro builder myself I could feel the same excitement you guys were feeling!

[jthowery]

where is the water generated creeks & streams or runoff ? Whats the efficency gpm vs output? Curious

[74VDC]

Joel...where on Earth did you ever find that turbine? Do you have any video or photos before installation? Who manufactured that turbine? A Francis seems an unlikely choice for such low head, but it's reliability makes it wothwhile it sems. Did you use the formula head X flow(cf/s) / 11.8

to come up with the expected 33 kW? By far the best micro-hydro I've ever seen...very nice workmanship....love it!

[74VDC]

I assume you apply 230v. to the induction motors prior to them generating...right? Won't start because you have removed the start winding, so initially the just sorta hum due to xfmer action before 1760 rpm is reached?

Who was the manufacturer of your turbine?