Saturday, August 30, 2014

Pelton Kaput...

*Pelton-wheel: A simple, most efficient type of water turbine, developed in the late 1800's by Lester Allan Pelton. The pelton-wheel extracts energy from the momentum of moving water under pressure.
                                                          ***********************
   Well, no thanks to old Lester, it has been a little dark around the Lodge for the past while. I didn't mention it in my last post, but the water driven pelton-wheel generator that runs the place packed it in last week. Was reduced to listening to a small gas job 6 or 8 hours a day to keep up the fridge, freezer, and a little Internet time. That's called roughing it around here. I had some maintenance scheduled in a few weeks but the gremlins beat me to it. Little bastards.
The pelton-wheel is pretty much trouble free other than a large rubber power coupler between the pelton-wheel and the 20kw generator, and two big pillow-block bearings it spins on, the only moving parts of the whole system of course.

 Over the years I gained quite the collection of the heavy worn out old couplers, they have a hard life.
I'm determined to come up with another use for them. Anyone have any ideas? I'll send them to you collect!
    I often feed people a line about all the 'free' green power being generated. But as you can see it comes at a cost alright. I still can't complain, it costs under $200 year to make more power than I can use.
The system provides electricity for major items like the ever important hot tub, washer/dryer, baseboard heating in the Lodge, guest cabin, and shop, several yard lights brighten the place up like I'm sure they can see it from the Space Station, and often powers a huge pair of pa speakers I like to play my drums through. It is good not to have neighbors. Power is sent down to run the small caretakers cabin at the hot spring. What electricity is not consumed, gets directed to a furnace and blown off into the atmosphere as hot, warm, or cool air, depending on how much is being used up. 
I know, it sounds bizarre.
I only consider cost as something I have to pay for naturally, which I just hate. I don't include my time, experience and effort, which is at times considerable.
   A mechanical problem like this now, that I was half expecting is not much of a hardship. I kind of got an inkling by now of roughly how long things last and time this kind of work for mild weather.
Not withstanding interference from pelton-gremlins of course.
Once in awhile you need to go over there and bugger around with a dial indicator and shims to keep the two units aligned as well, theres some big nasty parts spinning around at 1850 rpm.
    She's a pretty skookum unit, made right here in BC, and custom built for this application. Water shot from a nozzle at 200 psi propels the cupped wheel, the whole thing is very securely anchored to the thick cement pad.  I've come up with a few improvements along the way, like going from 2 pc couplers to a 1 pc, more difficult to replace, but longer lasting one. And these flange bearings on the shut-down deflector shaft I changed out last year. The shaft only moves a handful of times a year, but its obvious the constant splashing of water of the pelton-wheel inside the housing has taken its toll. I don't like things getting this far gone, but I didn't want to go put the same thing back on.
Hell,  only got 12 years out of them, and they were dripping water and rust junk all over in there. !

I tracked down something that would do the trick made from nylon, made in Germany actually, for what I don't know. It took a little work to adapt them, with some drilling and tapping new threads. 

I'd hope these new shut-down deflector shaft bearings will last the life of the machine. They only move when the machine is shut down for some reason, either manually by me, or if the controls sense a increase or decrease in the voltage and releases a large drop weight, which rotates a deflector in front of the water stream, and the pelton-wheel spins to a stop. Usually, if it shuts itself off it will be due to problems up the hill with the intake screen, if it is restricted it reduces the amount of water and lowers the head which in turn affects the pelton speed of 1850 rpm, which drops the voltage that trips the deflector. A worse case scenario would be a runaway, if for some reason you lost the "load" on the generator, (the lodge, hottub etc.) the wheel would speed up until finally something has got to give, like the whole machine flying out the roof of the power shack sort of ending.
The deflector drops to prevent this, those little nylon bearings do a very important job.

I packed the newly arrived parts over to the power shack this morning at first light. I had replaced the outboard bearing last season, and the inboard bearing was a bearcat to replace this time, requiring wheeling over the oxy-actetelyne tanks and blowing it off the shaft with the cutting torch.

Insert 7 hours of swearing, sweating, knuckle banging, sore back, mosquito slapping and making repeated trips back and forth to the distant shop for tools here.

And turned the water back on sometime mid-afternoon. Stylin' now. Lookout non neighbors!
I run over every few hours and check my work earlier today, giving it the educated listen as I walk over, listening for any little variance. I touch the bearings, to see if they are getting too hot, or if one is warmer than the other, if so, it gets shut down and tweaked with.
There is a digital panel in the Lodge that figures how to make the best use of your available power, it shuffles it around on a priority basis, making sure the most important electrical loads are taken care of first. High priority uses are the most important items of course. For instance, the hot tub, drum kit and shop are what you would call high priority areas. 
    By far the biggest challenge, and go ask anyone who has a similar hydro system, is the intake screen located up the mountainside at the intake pond. 
Hard Fall rains kick the creek up and clog the screen with debris, or in extreme cases, tear it loose and fire it over the falls and smash it to bits!
Bad cold makes frazzle ice in the creek and clogs the screen, and the lights, heat, and drum mics go dead at the Lodge at a very inopportune time of year, and makes me cranky as hell. Most of the entertainment is in trying to get up there under the most adverse conditions to begin to even deal with the problem, which for some perverse reason, is always when the lights go out, and the kit goes silent..., or at least somewhat quieter. 
That is beyond roughing it, and most of my planning, preparation and scheming go towards avoiding, or a least limiting the inevitable possibility.
   You know, I'm not going to go on too much more about the intake pond/screen right now. I'm going to climb up there soon enough and do a 'little' work to get it ready for the coming Winter.
That is bound to be a post in its self. 
I get a real kick from producing all this clean electricity from an endless resource, thanks Lester.  But it would surely be a different story if I had to pay some joe to keep it all up running smoothly for me, and he would sure hate me for those trips up the mountainside in the Winter.

7 comments:

  1. I thought you where a "Gentleman of Leisure".Looking at the pictures there wasn't much leisure going on. I guess it would cost to much to hook up to the power grid?? Casey

    ReplyDelete
  2. I am a Gentleman of leisure Casey, I just hate to be one in the dark. Theres been some rough looks into a line to the nearest grid, it works out to about a thousand seasons worth of bearings and couplers! Then theres that big hydro bill arrive every few months. You must be makin' plans for your Fall trip to the hotspring soon.

    ReplyDelete
  3. How does the water get up to 200PSI ? is that all from gravitation down the mountain?

    Next time I am up with the kids I would love to see this in action.


    ReplyDelete
  4. There is a 400' head (elevation) difference from the pelton up to the dam. That gives 200 psi in an 8" line, several hundred gal/min fire out a 3/4" inch nozzle to spin the wheel, that will do alot of work. I'll do a post about the penstock and dam later on.
    Sure, let me know if you'd like to see going some time.

    ReplyDelete
  5. Hi Robin, well we finally got back home to Kentucky and are settled down. We enjoyed our night 'for real' off the grid. Fortunately, we are died in the wool cavers and had several flashlights on us. Thanks for letting us stay.
    Shar did a good job tracking us down. Caught us as we were sitting at the paved highway debating which way to go. She recommended we go east, and she was right, it was a beautiful drive.
    The one mistake I made was not discussing your power plant with you, it did not cross my mind until we were long gone.
    Thanks again for the hospitality.
    Robin and Elizabeth

    ReplyDelete
  6. I'm glad you two stopped in for the night. I would have took you over to the wheel in the morning, but you got an pretty early start down to Sloquet hot spring, I'm sure you enjoyed soaking there as well. Come back sometime when theres no road closures, the powers on and you can stay longer. :)

    ReplyDelete
  7. John's AghastJuly 31, 2016 at 3:43 PM

    I'm sure that if you put the Pelton Wheel on a CONCRETE pad, rather than a 'cement' one, you'd have much more stability. Wonderful article! I envy you (except at repair times - in the winter).

    ReplyDelete