Author Topic: Low head hydro link (Read 21233 times)

kenl · « **on:** February 03, 2010, 08:21:21 AM »

Found this link while cruising Home Powers web site. I read how a lot of people out there have high flow but low head streams etc and want a way to do hydro. This system appears to work well and from my searches is used all over SE Asia. Wifes visiting her parents in Thailand near the Loas border right now, may have to see if she can pick one up for me. They run about $100-$150 USD over there.

http://www.powerpal.com/ This link is for a company out of Canada that sells them. Looks like with a little reverse engineering one could home brew the design pretty easy.

kenny

seemed like a good idea at the time

GeeWiz · « **Reply #1 on:** January 31, 2010, 10:05:25 PM »

Interesting link. They say 200watts at 1.5 meters of head.

Here is a link to their manual ; http://www.powerpal.com/lowheadmanual.pdf

Anyone have any 'experience' with them ?

willib · « **Reply #2 on:** February 01, 2010, 08:23:54 PM »

I wish i had flowing water of any kind on my property.

what i would try is a paddle wheel type of setup.

about 5 feet in dia.

about two feet wide.

and sticking in the water about a foot.

Float the wheel on a pontoon and gear it up so the alternator is spinning about a hundred rpm.

That gismo in the link , well i would save my money for a pontoon.:-)

ghurd · « **Reply #3 on:** February 02, 2010, 06:32:38 AM »

Chris Greacen put up some pics and videos.

http://palangthai.blogspot.com/

Also

http://www.fieldlines.com/story/2008/6/22/191210/965

Looks like a motor conversion to me.

G-

ADMIN · « **Reply #4 on:** February 03, 2010, 08:19:59 AM »

I've recently been in contact with PowerPal in Canada, and they were very helpful. I've recommended one of their turbines to a consulting client in Canada.

These are not high tech turbines, and they require regular maintenance on the submerged bearings (even the latest version). Every 12 weeks I believe!

If you want a low-head unit that will last a long time with little maintenance, go with the ES&D:

http://www.microhydropower.com/Low%20Head.htm

However, it is much more expensive and is 3-phase rectified to DC only (thought there are 120v and 220v versions for long transmission lines). For differing heads, you can get different length draft tubes, so the ES&D can work from 2 to 10 feet of head.

The PowerPal is AC output only, with voltage and frequency regulated by the control unit located away from the turbine. It is NOT adjustable for head, 1.5 meter is your only option; the intake sluice and turbine runner are designed so that close to the correct RPM will always be happening, and the regulator just tweaks it. However, there is info on their discussion forum about replacing the turbine runner with a homebrew version, to give proper RPM at higher heads (after extending the draft tube of course).

The PowerPal is also sensitive to reactive loads, like large battery chargers (ouch). These can cause the stator to overheat and burn out. Compact Flourescents work fine on it -- but you should source good CFs, not the crappy Chinese ones that have a high power factor (very reactive). You could add capacitors....but probably would need to do that to each CF, as total load reactance would vary depending on how many were turned on. It's no longer difficult to find low-power-factor CFs.

However -- if you need an energy source that doesn't have any storage, the price is right on these PowerPal turbines. Under $1000 for the entire system, including intake sluice, turbine and regulator, and shipping to the US or Canada from Vietnam.

That's 1/3 the price of the ES&D unit, with no need (or option) for a battery bank and inverter. Just be aware the PowerPal is maintenance-intensive.

ADMIN

Ungrounded Lightning Rod · « **Reply #5 on:** February 03, 2010, 12:37:56 PM »

I'd expect cheap CFLs to already have leading, rather than lagging, power factor. Diode charging a filter capacitor that discharged on the downslope as the "raw supply", so current drain is early in the cycle. If that's the case adding capacitors would make 'em worse rather than better.

Are they designed some other way so they appear inductive?

WoodWaterWheel · « **Reply #6 on:** February 04, 2011, 09:02:20 PM »

I've located the manufacturer for PowerPal low head turbines (their Canadian website http://www.powerpal.com/lowheadmanual.pdf ) in Vietnam and am considering ordering several units for different sites in GA and NC directly from the manufacturer. These units are very simular to the ES&D model LH1000. I add this fact because someone may be familar with them which means more responses. The PowerPal models I'm ordering are MHG-1000, MHG-500, and MHG-200 to match the different flows @ these sites.

I need to hook these 120v AC units up to 12v and 24v battery banks and am not sure how to do it. The units appear to only have 2 wires coming out of them so I don't think I can hook them to a rectifier like I would with the altinators I currently use. The altinators I currently use run through a charge controler with a dump load to protect the batteries and the battery bank and charge controler (a Flexcharge) keep the voltage low.

So, How do i inexpensively get the 120v AC current into DC suitable for the 12v and 24v battery banks. I was planning on tossing the included 120v controller and instead do use the charge controller for the batteries with the PowerPal heat sink. Is there a rectifier built into these units converting them to 2 wires that can be easily removed allowing me to run 3 wires to a standard automotive type rectifier @ the battery bank??? I don't mind doing some minor modifications to them but I'm not an electrical engineer and want to keep things easy. I'm attaching the power chart the manufacturer sent me for reference.

thanks for any assistance.

PPal data.pdf (19.14 kB - downloaded 392 times.)

hydrosun · « **Reply #7 on:** February 05, 2011, 01:25:31 PM »

Everything I've read about the Powerpal has been about the low quality and high maintenance because of the underwater bearing. Using a better sealed bearing has lengthen the bearing change interval. I think some importers are doing that upgrade. But it isn't a great design. I don't think the ESD has any underwater bearings. Efficiency is lower than the ESD because there isn't any way to adjust to different heights or different voltages.
If you want to charge batteries you need a battery charger. Or make your own with a transformer to lower the voltage and a one phase rectifier. As someone else mentioned the efficiency goes low doing that. The Powerpal has it's place where small amounts of power (less than 200 watts) is used at 120 volts AC. But if bigger loads are run and you need to store into a battery to run an inverter the losses are huge.
The ESD may be three times the cost but it is just one component in the system. Pipe and wire can cost as much as the turbine. A higher efficiency system will put out more power for the investment.
If you only need a small amount of power and you are willing to do more maintenance the the Powerpal may work for you.
Chris

WoodWaterWheel · « **Reply #8 on:** February 05, 2011, 10:18:16 PM »

Chris, First let me say that I had already intended to replace the bearings with ceramic bearings. I'm on good terms with 2 bearing suppliers so the bearings shouldn't be a problem. The ES&D unit also has a submerged bearing and from what I've read still needs bearing maintence every 3 months. In addirion to this Power Pal has redesigned their units in the last 2 years to improve their reliability. I also intend to balence the shaft/ turbine head and while the windings are expected to last only 5 years acording to a humantarian group report (I can't find the online report @ the moment) I read I also intend to secure a small fan inside the casing to lower the internal temperature hopefully extending the unit's life. This same report listed the Power Pal unit to be the most reliable of these low head low cost units avaliable. Having said that as you mentioned the unit is less than 1/3 the cost of the ESD unit even after these modifications and shipping.

The low rpn altinators I currently use on the water wheels are capable of over 150v but the battery bank and charge controller keep the voltace @ either 12v or 24v depencing on the setup so I'm not so sure about the need for a transformer so U guess my big question remains how to get the ac voltage into dc with only 2 wires comming out of the unit. Does anybody know if there are simply 2 wires in the unit which can be run to a rectifier o give me DC power???

Lowhead · « **Reply #9 on:** February 06, 2011, 03:07:27 PM »

I am running an ES&D LH1000 and going on 2-1/2 years without yet needing bearing replacement. This is one tough unit. I have had it completely submerged in a spring flood and after dumping the water out of the junction box and cleaning up some corrosion on the rectifier terminals it still worked like a charm. I too looked at the PowerPal but decided to avoid it. You get what you pay for.

WoodWaterWheel · « **Reply #10 on:** February 26, 2011, 11:05:22 PM »

Ok, After looking at the total cost of the ESD and Power Pal units after importing and building the canal and draft tube (for the PowerPal) the price is too much for the electricity produced and I can build a durable unit for about half the price using balenced impellers and highly efficient alternators with stainless steel impeller shafts. Do you guys think there is a market out there for a unit like this in the $1300 range that can make over 1000 watts?
Spencer

hydrosun · « **Reply #11 on:** February 27, 2011, 01:17:22 PM »

If you can do it well at that cost, I think there will be a market for it. Even on this site there seems to be many questions for sites that could use that type of turbine. Heck I know of several sites in my area that could use it.
Chris

WoodWaterWheel · « **Reply #12 on:** February 28, 2011, 08:45:45 PM »

Chris, The 1st prototype for this low head turbine is built and the PMA mounts will be machined in the next few days. I have a 13' deep lake that I've drained for dock maintence and I'll start refilling it in about 3 weeks. Since it has a 18" drain pipe with a cap allowing me to take water off the lake from the bottom I intend to test this turbine at different heads and flows as the lake fills (a 1 month process). This 1st prototype has a 6" impeller with a stainless steel shaft and the bearings are designed for easy replacement when needed although some care has been taken to minimize the bearings exposure to the water so they should last a good while. Power and flow will be dependent on head but I'm looking for a mininum efficiency of 55% (hopefully higher since the impeller is a more efficient design) but @ 55% this unit should produce 1330 watts with 10' of head and 2100 gpm. The maximum head will be somewhere over 20'. The turbine will handle it, just need to match the alternator to preform at the higher speeds but most people don't have high flow high head locations. The question is how low of a head and flow will it start to make usable power (over 100 watts) - testing will tell. This unit is designed to allow for several different alternator windings to allow it to match the site to maximize output. I'll try to post the testing results as the lake fills. I also am working on a smaller turbine for lower flows. b][/b]

WoodWaterWheel · « **Reply #13 on:** February 28, 2011, 08:51:37 PM »

P.S. Still on track for the $1300 target price with a 500 watt unit probably costing about the same but more efficient for lower flows.

kenl · « **Reply #14 on:** March 03, 2011, 10:44:10 AM »

Spencer,

Any chance of a picture or 2? Just curious of what it looks like, I have no water other then a gallon or 2 a minute spring where I'm at so hydro is just a curiosity to me.

kenny

seemed like a good idea at the time

hydrosun · « **Reply #15 on:** March 03, 2011, 04:20:45 PM »

At 10 feet head and 2100 gallons would give 2100 watts at 50% efficiency. The ESD units charts say 10 feet head and 1000 gpm and 1000 watts. Did you divide twice:) ? or is one number different. I'm not sure about the diameter of the ESD unit. Actually testing your unit will show real output. I'm glad to see your progress.
The real advantage of the ESD turbines is the adjustable magnet and being able to rearrange the stator winding to match power input at a wide range of sites without having to build different alternators for each site. They use the same alternator case for the high head turbines too.
Chris

WoodWaterWheel · « **Reply #16 on:** March 06, 2011, 04:16:46 PM »

Chris, The ability of the ESD unit voltage and load to be customer modified onsite is a nice feature and one a machinest friend of mine is trying to reproduce but the 1st unit I'm making will need the alternator matched to the site although the guy who made the prototype winds his own PMAs so at least I have options when it comes to matching the alternator to the site. Until I've actually begun to test this thing I'm not going to comment on its efficiency but the manufacturer shows the PowerPal being 50% efficient and and the ESD unit comes in right at 53% efficiency from 3' to 10' of head. While I can only guess at these units turbine sizes the Power Pal 1000 shows the unit fitting in a 7" downdraft tube and the ESD 1000 paperwork calling for a 8" downdraft tube. This 1st prototype of my turbine is using a 6 1/8" diamater impeller with .020 clearence between the impeller the the housing walls so it probably won't hit 1000 watts until it gets a little more head. This 1st unit is primarly designed to allow me to work with different pitches and measure different flows vs rpm to help calculate the water slippage over the blades.

hydrosun · « **Reply #17 on:** March 07, 2011, 12:08:42 PM »

I wasn't actually commenting on the efficiency but just wondering about the 2100 gpm you were using. The ESD charts says it uses 1000 gpm at 10 feet head so I was wondering if your unit was larger. I'm not clear on how to calculate the gpm for these units. The downdraft tube is proportional to turbine size as it flares out a little larger. Measuring what actually happens will give you the numbers needed to decide what the alternator design needs to be.
Chris

WoodWaterWheel · « **Reply #18 on:** March 07, 2011, 06:29:59 PM »

Chris, The 2100 gpm figure I was using was when I was trying to make a unit simular to the ESD and Power Pal units outputs back when I thought they were using 6" impellers (power pal actually shows over 1500 watts @ 2100 gpm with higher heads) but I think they are using larger impellers than the 6" unit I'm using. In addition to that my impeller has a tapered hub squeezing the water tighter and faster as it moves down the impeller so upon reconsideration (reality check) this 1st unit probably will flow closer to 600-700 gpm @ 10' of head. Testing will tell. At this point I'm more interested in the efficiency of the unit. If it ends up with good efficiency (meaning it is a viable design) then the impeller size and pitch can be changed to see what works best. In the testing process I'll be testing it with and without a draft tube to see what the power output is between the 2 and at 2 different heads. The bottom line I'm trying to make a reasonabaly priced efficient turbine that will last 10-20 years with minimal maintance. In 2 weeks you're either going to hear me shouting for joy or wimpering in the agony of defeat after the initial testing to see if this unit is as efficient as I hope.
Spencer

Lowhead · « **Reply #19 on:** March 09, 2011, 10:31:39 PM »

The LH1000 uses a runner that is close to 5 inches in diameter. The draft tube is only 4 feet long. If you have head longer than that you insert a length of 6 inch schedule 40 PVC pipe up to a max head of 10 feet. The 6 inch pipe is connected to the cast urethane housing of the LH with 6 inch rubber coupler with hose clamps and to the draft tube the same way. The urethane housing is only 5.5 inches in diameter so you really need to tighten the rubber couple down a lot to get an airtight seal. The runner is inside the housing which is 1/4 inch thick and hence the 5 inch diameter.

WoodWaterWheel · « **Reply #20 on:** March 12, 2011, 10:11:18 PM »

LowHead and Chris, Thanks to that informaton about the 5" downdraft tube on the ESD unit (1000 watt model??? ). I've never seen one and can't afford to buy one just to play around with. My test unit has a 6" impeller with a 6' pvc downdraft tube which will be tested both with and without the downdraft tube at several different heads. I mounted the turbine today on the standand hope to test next week weather permitting.

hydrosun · « **Reply #21 on:** March 17, 2011, 09:54:02 PM »

I just read in Homepower magazine that Ecospout hydro will be offering a turbine similar to the ESD low head soon. They use the Fisherpaykel motor on their pelton turbine so I would assume they will use it on the low head unit too. I have no details yet but thought you might be interested that someone else will be entering this niche market.
Chris

Lowhead · « **Reply #22 on:** March 19, 2011, 10:03:04 AM »

I've always been fascinated by the Leffel Hoppes unit:

http://www.frenchriverland.com/leffel_hoppes_unit.htm

I'd love to find an old one and put a PMA on it.

MaxtorD · « **Reply #23 on:** April 23, 2011, 03:21:58 PM »

That is a sweet link. Thanks.

WoodWaterWheel · « **Reply #24 on:** April 24, 2011, 05:36:50 PM »

Ok, It's been more than 2 weeks like I claimed before but 1st unit tested well at 47% efficiency. I've since built 3 prototypes and am now getting over 52% efficiency in real world testing. The primary reason for 3 testing models is for ease of service and to adjust the impeller pitch. Even the 1st unit worked well but sand and grit made disassembly really hard for the annual bearing change. Also the impeller clearences were too tight but now electrical output is strong and reliable even if you feed the turbine a bucket of crawdads. Got that problem licked now with the annual maintance taking less than 10 minutes and the 2 yr maintence taking 45 minutes. Cleaning any leaves or crawdads out of the unit takes 2 minutes I've tested 7 well made PMAs to get the ones that worked best with this turbine and am currently building 5 turbines using CNC machines to see how they sell. This turbine rocks for about half the price of the ESD unit. Bottom line is that I'm making a turbine that I would want to maintain over the years and makes lots of electricity. Look for them in about 4 weeks.
Spencer

Harold in CR · « **Reply #25 on:** April 24, 2011, 05:42:23 PM »

What wattage output at what head and flow ?? I have a very limited site. Charts all state 60 watts output. I need all I can get.

WoodWaterWheel · « **Reply #26 on:** April 24, 2011, 06:42:45 PM »

Harold, The unit I just described makes between 50 and 1100 watts depending on your site and probably isn't a good choice. I'm not sure what "charts" your're referring to but I've found most online charts to be pretty accurate. Online power calculators are out there. One is at http://www.waterwheelplace.com/low_rpm_alternators.html Since at lower heads most turbines aren't very efficient use .45 for the efficiency to see how good your site is. I've been trying to figure how to put this javascript calculator on fieldlines.
Spencer

Harold in CR · « **Reply #27 on:** April 24, 2011, 07:33:21 PM »

Spencer
I have 30+ GPM at 20' of head. During the rainy season, I should get over 40 GPM, but, figure at 30+. Right now, it's just under 20 GPM, (dry season), until next month. This will be for 9 months or so.

I will try your calculator. That is what I meant to say, instead of "Charts". My mistake on terminology. I want to try a small scale Ossberger cross flow turbine, because I will have an ever changing flow, and can auto regulate the Ossberger.

Also have Pelton cups carved out of wood, to mold some up for building a wheel.

Ungrounded Lightning Rod · « **Reply #28 on:** April 27, 2011, 11:46:16 PM »

Quote from: Lowhead on March 19, 2011, 10:03:04 AM

I've always been fascinated by the Leffel Hoppes unit:

http://www.frenchriverland.com/leffel_hoppes_unit.htm

I'd love to find an old one and put a PMA on it.

I think I saw one of those in the Sierras - either along US 50 or CA 88.
I'll try to take a closer look the next time I go past it in the daytime.

WoodWaterWheel · « **Reply #29 on:** June 04, 2011, 07:41:26 PM »

Chris, After 3 prototypes and 4 months of testing using different impellers and PMAs I've finally got something you may be interested in. You can see it @ http://www.newturbine.citymax.com/catalog/item/8135014/8812932.htm
Spencer

hydrosun · « **Reply #30 on:** June 16, 2011, 02:11:19 AM »

It looks like a winner. I'll keep it in mind when I talk to some people with low head sites.
Chris

WoodWaterWheel · « **Reply #31 on:** June 17, 2011, 11:01:08 PM »

Thanks Chris, I'm really excited about building a low cost low head turbine.
Spencer

ruddycrazy · « **Reply #32 on:** June 22, 2011, 05:00:16 AM »

Hi Spencer,
That unit does look the goods but that lower bearing from my point of view is the only failing point of the design. Now just thinking out loud here but if you put a dual tapered bearing array above the water line point then the lower bearing could be some hard wearing engineering plastic with say a 0.003-5" clearance. Provided the tapered bearing set had the correct pre-load and the right lubrication system then the unit could go for several years non stop and by using the right plastic for the lower bearing it could last a lifetime of service.

Cheers Bryan

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Author Topic: Low head hydro link (Read 21233 times)

ADMIN