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Off Grid Via Slow Moving River?

michael posted more than 10 years ago | from the make-sure-you-have-plenty-of-candles dept.

Technology 452

einstein writes "I live out in the middle of nowhere, and I lose power at the drop of a hat. My house is right next to the Susquehanna river, and all the kinetic energy going past my house makes just want to go off grid. Most homebuilt hydro power is lower volume/high speed. What would be a good, unobtrusive way to generate electricity from a high volume/low speed body of water? I'm between two large hydro dams, so the water level is fairly constant, but does tend to fluctuate 4-6ft in the winter due to ice floes and melting snow. I think maybe a miniature version of one of the recent submerged tidal generators might work... Does anyone have some suggestions on how I might go about this project?" More than a few people have done this before.

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Poll Troll Toll (-1)

PollTroll (764214) | more than 10 years ago | (#8831874)

Which is better...

Grid []
Moving []
River []
Sex with a mare []

The Romans (4, Interesting)

panxerox (575545) | more than 10 years ago | (#8831881)

did something similar, they had a line of floating grain mills across the Tiber (no ice there though) in the late empire period. Find a good high current area and build a paddlewheel boat basically with the drive attached to a generator and use anchors in the riverbed. It might not generate a steady high elec current so you might want to put in a bank of batteries and converter for peak demand. Since the paddlewheel is in the back the boat draft would break up at least thin ice. With underwater turbines your talking alot of cost both in construction and maintainance. Hers another option

Re:The Romans (5, Insightful)

mikewas (119762) | more than 10 years ago | (#8831953)

Probably easier to build a dock, floating or fixed. A dock is something that the local officials will understand so any permits or approvals should be easy. Then attach the paddlewheels.

Stay on-grid while generating power (5, Insightful)

Anonymous Coward | more than 10 years ago | (#8831882)

If you manage to generate your own power (wind, water, solar, whatever), stay on the grid because YOU can feed the grid, and the power company (usually) has to credit you. Yes, keep some of your own power stored up in batteries, but sell the excess and pay off the costs of setting this up.

Re:Stay on-grid while generating power (1)

Neophytus (642863) | more than 10 years ago | (#8831922)

An energy efficient home in the uk that generates it's own power through wind (people high up on hills) can pull a tidy side income to help pay for that next holid^H^H^H overclocked uber pc.

Re:Stay on-grid while generating power (3, Interesting)

gleekmonkey (737957) | more than 10 years ago | (#8831950)

A friend of mine makes over $600 a month by staying on the grid and setting up a few wind towers.

which systems (1)

zogger (617870) | more than 10 years ago | (#8832086)

... does he use?

One of the weird things about enron is, they actually had at least one decent product. they made whopper wind gennys. GE bought them at fire sale prices and are still making them, last I knew. I actually tried to get some rich dudes to buy them out as soon as I heard of enrons troubles, but no see gar there sad to say. I think it's an excellent way to actually pay for a nice spread out in the country, make all your loot + pay for property + have oodles of free juice to play with. If I had the VC I'd do it/organize it, but never really tried anything that ambitious before. It gets quickly into 7 figures though for the whopper systems.

Re:which systems (0)

Anonymous Coward | more than 10 years ago | (#8832098)

He owns a farm in Alberta, Canada where he puts them up.

Re:Stay on-grid while generating power (1)

madprof (4723) | more than 10 years ago | (#8831989)

There are people in Australia who get money from the electricity people through their solar panels feeding back into the grid too.

Re:Stay on-grid while generating power (1)

trmj (579410) | more than 10 years ago | (#8831990)

I believe that's a federal law here in the US, and if not, it's at least a state law here in PA, but I don't know about NY (PA and NY are the two states the Susquehanna river is in).

Re:Stay on-grid while generating power (1)

skilm (319925) | more than 10 years ago | (#8832034)

The Susquehanna is in Maryland too...

yes, but investigate 'net metering' (1)

way2trivial (601132) | more than 10 years ago | (#8832054)

do they sell at the same rate they buy from? depends on the state..

Re:Stay on-grid while generating power (5, Informative)

MrChuck (14227) | more than 10 years ago | (#8832021)

I'm in the process of Solarizing an odd grid house...

Battery system will add a bit to the cost (but still might be worthwhile for keeping "absolutely needed" systems up (refrigerator)). But unlike solar, rivers run always. You can start without it and power your house, sending extra to the grid and making money on it.

But note that a Rolls 375AH battery will cost you $600-$700 and you'll want a few of those. Plus charging systems for them. And replacing them every 5-8 years. (tho fuel cell systems are expected to work for this use within 3-5 years).

HomePower Magazine [] is online and in libraries and just had something (Feb? March?) on home hydro [] . It's often used with creeks. You can also buy their entire archives on CD.

If you need pressure, but don't think your river has it, note that running water into a large pipe and getting smaller makes pressure enough to turn things.

The easiest way to handle it is with a, er, hill. Divert some of the water off through pipes, let it drop, let it hit your generator and route it back to the river. Filters and cats at the top keep fish out.

Re:Stay on-grid while generating power (2, Informative)

jdhutchins (559010) | more than 10 years ago | (#8832074)

You probably have to tell the power people though, and they'll probably be very stubborn. Besides crediting you, there are technical issues associated with feeding the grid. The power grid is carefully controlled, and if you don't do it right, you'll screw it up.

Re:Stay on-grid while generating power (1)

yintercept (517362) | more than 10 years ago | (#8832143)

I imagine that there might also be politic battles over the generative power of the water that flows through the river near your property. Waterways are generally considered public throughways; so you probably have to go through a nasty political process to access to the river.

Come to think of it, if you wrapped copper wires around the lawyers that will get involved with the project, and hooked up a turbine...

Re:Stay on-grid while generating power (2, Interesting)

Anonymous Coward | more than 10 years ago | (#8832078)

If you stay on the grid make damned sure somebody from the local power company inspects your setup. If the power on the grid goes out and the power company employees are working on the lines, your power generation feeding the grid could be enough to kill somebody.

Re:Stay on-grid while generating power (1, Informative)

Anonymous Coward | more than 10 years ago | (#8832134)

yes we're told around here that any and all generators (sources of energy) must NOT feed the lines. as feeding the lines will put electrical workers at risk of a powered line that they believe to be dead. completely against the law to feed a dead line

Safety first (1, Funny)

Anonymous Coward | more than 10 years ago | (#8831883)

Didn't anyone ever tell you that water and electricity don't mix? That's good enough for me.

Re:Safety first (0)

Anonymous Coward | more than 10 years ago | (#8832096)

OH come the fuck on! It's a JOKE! A bit lame, but still A JOKE. Troll? Please!

How on earth is this a troll? (0)

fmita (517041) | more than 10 years ago | (#8832144)

Mod the parent back at least to 0, for the love of god.

What the ..? (1, Funny)

Anonymous Coward | more than 10 years ago | (#8831895)

Doesn't everybody have there own anti-matter reactor?

No, of course not (0)

Anonymous Coward | more than 10 years ago | (#8831905)

I generate my power using a quantum singularity.

Re:No, of course not (4, Funny)

Dasaan (644170) | more than 10 years ago | (#8832062)

pfft, a mere toy! I use one of these []

Check out Home Power magazine (5, Informative)

no_such_user (196771) | more than 10 years ago | (#8831901)

I'm a big fan of Home Power magazine [] . They focus more on solar solutions, but you'll catch an occasional article on hydro. Best part is you can download the current issue [] for free (after registration).

stating the obvious (0, Offtopic)

monkeyboy87 (619098) | more than 10 years ago | (#8831902)

imagine a beowulf cluster of micro turbines....

Motivational Speaker? (5, Funny)

niko9 (315647) | more than 10 years ago | (#8831909)

You woudn't happen to wear a 50's era bifocals and live in a van down by the river?

Township Approval (5, Informative)

Anonymous Coward | more than 10 years ago | (#8831910)

What would be a good, unobtrusive way to generate electricity from a high volume/low speed body of water?

You'll need township approval before even thinking of constructing something that could possibly damn or slow down the flow of water.

Re:Township Approval (0)

Anonymous Coward | more than 10 years ago | (#8831939)

What if he doesn't live in a township and owns the river himself?

Re:Township Approval (0)

Anonymous Coward | more than 10 years ago | (#8831968)

How many people own rivers?

Re:Township Approval (4, Informative)

virtual_mps (62997) | more than 10 years ago | (#8831974)

What if he doesn't live in a township and owns the river himself?

Heh. The susquehanna is the 16th largest river in the united states, not some backyard trickle. It's a navigable river and a major feeder for the chesapeake bay, which falls under federal authority as well as state and regional environmental regulations. Sticking a dam on it is something I'd probably ask a lawyer about first thing.

John Ashcroft (3, Insightful)

EventHorizon (41772) | more than 10 years ago | (#8831970)

We need government approval to think? Damn. That's worse than 198


Maybe where you live.. (2, Informative)

itomato (91092) | more than 10 years ago | (#8831985)

In some places, as long as you don't completely block the flow, just about anything goes. It may be inconsiderate, but if it is, then you've got more than a few neighbors downstream to contend with when they find out it's you!

Common sense, fairness, and respect go a long way in the country. That's why it rules so fucking much!

Re:Township Approval (1)

MrChuck (14227) | more than 10 years ago | (#8832045)

Um, pulling a pair of 3" pipes off (with filter/screen at the top) and running it over to a microgenerator probably won't stop much of the river. or slow it down.

(he did use the work "unobstrusive" so he's prolly not envisioning a 30' high cross river damn (that might also upset neighbors upstream).

Re:Township Approval (4, Funny)

tunabomber (259585) | more than 10 years ago | (#8832109)

You'll need township approval before even thinking of constructing something that could possibly damn or slow down the flow of water.

Crap. Better rethink my plans to build a Church of Satan on the bank of the Animas River (in my backyard). The people of Durango might not be too happy that their river has been condemned to eternal damnation, especially since "animas" is Spanish for "soul".

Re:Township Approval (1)

Geoffreyerffoeg (729040) | more than 10 years ago | (#8832118)

damn or slow down the flow of water

I don't think water has much of a chance in Hell. ;-)

Donald Duck (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#8831914)

Donald Duck is going to have a SCREAMING SQUIRMING ORGASM when he gets this set up out in the woods so that he can power his vibrating butt-plugs that he so loves to play with when he's spending time with Daisy Duck.

Dear Slashdot (5, Funny)

Anonymous Coward | more than 10 years ago | (#8831924)

I've noticed while wearing socks and walking on carpet, I often generate static electricity. Is there any way to harness this electricity to power my home, rather than shock me when I touch metal objects? In a related question, could I somehow generate power by rubbing balloons against my hair?

Re:Dear Slashdot (2, Interesting)

Jozer99 (693146) | more than 10 years ago | (#8832105)

Yes! First, get some spectacularly fuzzy socks. Then, wire every one of your door knobs into a giant capacitor, and have that trickle into a battery.

High torque (4, Interesting)

680x0 (467210) | more than 10 years ago | (#8831928)

I bet you could build a low-speed, high-torque paddle wheel (it would need to have a lot of surface area being pushed on by the river). Then, using gear ratios, you can convert that to high-speed, low-torque that may be needed by your generator. Not being a mechanical engineer, I'll leave it at that. :-)

Wind Power! (3, Funny)

Anonymous Coward | more than 10 years ago | (#8831930)

The basic idea behind hydro power is that you take the potential energy of water falling a vertical distance, and convert it to electrical energy. You will have trouble with that in your area. The fact that the river is slow movign tells me that the gradient in the area is very gradual, so it will be difficult to rig up a system where the water is able to travel a vertical distance. Basically you would have to build a dam to block the flow of water so it rises on one side.

I don't think tidal power would work unless the river level fluctuates daily (tidal generators produce power only during a level change).

My suggestion: forget hydro power, and build a windmill!

Re:Wind Power! (1)

sploxx (622853) | more than 10 years ago | (#8831965)

Potential energy extraction is not the only possibility.
You can also extract *kinetic* energy of the water in undershot water mills.

I endorse this. (0)

Anonymous Coward | more than 10 years ago | (#8832110)

... as it would give /. editors and -bots another useful target to tilt at.

PS. Michael, you're a goat-pleasuring son of a one-eyed whore. Happy Easter, bitches!

does this remove energy from the current? (4, Interesting)

polished look 2 (662705) | more than 10 years ago | (#8831940)

ok, say this person puts in a paddle-boat or what-not which drives a generator. Does this remove energy from the river? will the downstream hydro-electric plant have less energy?

Re:does this remove energy from the current? (0)

Anonymous Coward | more than 10 years ago | (#8831955)


If you put enough generators in chain, water will stop moving or will start flowing upwards :).

Re:does this remove energy from the current? (2, Informative)

GarthSweet (514087) | more than 10 years ago | (#8831969)

Without understanding hydro dynamics at all I can comfortably say that if you gain some energy from the water then yes it has either lost some kinetic energy (or some mass)

Re:does this remove energy from the current? (5, Informative)

RallyNick (577728) | more than 10 years ago | (#8832016)

yes, but just momentarily. once past your paddle, the water will be accelerated again by earth's gravitational pull, so the downstream power plant won't ever notice.

p.s. it wouldn't notice anyway since they just store the water in the dam and let it free fall on their turbine from there. so your plant will make the water take longer to reach downstream but it'll have just as much energy once there.

hydroelectric power (3, Interesting)

gordona (121157) | more than 10 years ago | (#8831942)

You'll probably have to divert some water through a small sluice, but you'll have to find out if you legally can do this. You can emphasize that it will be 100% conservative, ie., no water will be consumed. A turbine in the sluice can be geared to drive an generator at higher speed. Will no doubt have to play with the size of the sluice and the gearing etc, since you will have essentially no head to play with.

I was going to suggest photovotaics as well (0, Funny)

miracle69 (34841) | more than 10 years ago | (#8831943)

But then I saw that you were in England []

Have you considered gas powered generators at all? They're likely to be cheaper, easier to maintain, more powerful, and reliable.

What are your electricity needs?

Uh, not too many Native American rivers in England (1)

spineboy (22918) | more than 10 years ago | (#8832006)

The Susquehanna river is located in the Eastern USA, namely Pennsylvania, and it might also start in NY and end up in Delaware and Maryland. (New)Jersey may even see part of it.

Re:Uh, not too many Native American rivers in Engl (0)

Anonymous Coward | more than 10 years ago | (#8832079)

Did you even bother clicking the link in the grandparent's post? The map linked to clearly shows that along with many cities labeled that happen to share names with cities in England...

Re:Uh, not too many Native American rivers in Engl (0)

Anonymous Coward | more than 10 years ago | (#8832119)

The map also contains state names like New York, Pennsylvania and Maryland indicating pretty clearly that it's the United States.

Re:I was going to suggest photovotaics as well (0)

Anonymous Coward | more than 10 years ago | (#8832007)

Damn you're stupid.

Re:I was going to suggest photovotaics as well (1)

abrotman (323016) | more than 10 years ago | (#8832014)

I'd like to point out there is a susquehanna river that runs through the center of Pennsylvania. With an East and North branch. i believe it enters the atlantic into the chesapeke bay.

Re:I was going to suggest photovotaics as well (0)

Anonymous Coward | more than 10 years ago | (#8832097)

Try clicking the link in the grandparent's post. The map linked to clearly shows that along with many cities labeled that happen to share names with cities in England...

Wind Power (3, Interesting)

Denix (125207) | more than 10 years ago | (#8831946)

I'm not an expert on this but I believe you would also get wind off the river. So you could combine water turbines and windmills.

Too expensive (0)

durp (769886) | more than 10 years ago | (#8831956)

For all practical purposes I would say this is far too expensive. Where do you live?

Water wheel at mill stream (1)

jhines (82154) | more than 10 years ago | (#8831963)

Traditionally, the old grain mills used a big water wheel, which turned at a low rpm, to drive the mill stones.

An undershot wheel, where the water goes under the wheel would work, if you can force the water under, and not around it.

From there, simple gearing will give you what ever speed you need.

Why not just.... (5, Funny)

gleekmonkey (737957) | more than 10 years ago | (#8831964)

Why not just use humans? Just make a computer based reality world to keep them happy, and harness the energy.

Re:Why not just.... (3, Funny)

ActiveSX (301342) | more than 10 years ago | (#8832020)

No, no. Didn't you listen? You make a computer based reality to keep them miserable, not happy. Otherwise they won't believe it's real.

Re:Why not just.... EQ; SWG; DAOC? (0)

Anonymous Coward | more than 10 years ago | (#8832102)

They have all ready done that. Have you heard of Everquest? Star Wars Galaxy's? or Dark Age of Cammalot? All of those and i'm sure there are more are virtual reality that people spend alot of time doing. . . So the question is who is the genious who will figure out how to use the energy?

Do Some Homework (5, Informative)

klausner (92204) | more than 10 years ago | (#8831966)

There is a huge amount of material from the 19th century on mill design, and how to get the most out of river power. Try doing some research in a major library.

MOD PARENT UP!!! PLEASE (0, Offtopic)

spineboy (22918) | more than 10 years ago | (#8832036)

just ignore me.. THe parent has some good insight. Why bother to reinvent the wheel, there is a reason that many people used water powered wheels on slow moving rivers.

Don't reinvent the (water) wheel (1, Insightful)

Anonymous Coward | more than 10 years ago | (#8832094)

I would do just as the parent says, some of this research will be invaluable. There are things which you probably haven't thought of like

filtering: stopping debris getting in
anti-fouling: preventing the buildup of algae and weed
governing: stopping the wheel going too fast in a storm

There is doubless a lot of 'lost knowledge' about - people have been doing this for hundreds of years and most likely the best solution is low tech rather than high tech.

Govt Regulations (2, Informative)

codepunk (167897) | more than 10 years ago | (#8831973)

You may need to rethink that idea if you have any sort of state regulations like we do here in Wisconsin. Here you cannot make any sort of man made diversion, dam etc without drawing a serious amount of heat. It is quite likely you will run into the same sort of problems where you live as well.

Re:Govt Regulations (1)

fmita (517041) | more than 10 years ago | (#8832123)

Well that's good. you could build a dam, and then use this "heat" you speak of to power a turbine, and voila! power!

Height differential? (2, Insightful)

ramk13 (570633) | more than 10 years ago | (#8831975)

You either need water moving at a good velocity (kinetic) or some sort of height difference (potential) to generate a reasonable amount of power. (assuming you don't want a enormous paddle) I doubt you'll be able to dam the river in any way yourself without getting some sort of permit, because dams can have serious environmental impacts.

Legal ? (-1, Interesting)

Simon Lyngshede (623138) | more than 10 years ago | (#8831979)

Is it even legal to deploy you own home build hydropowerplant?

Even if it is, perhaps you shouldn't, there are always the potential of detroying the local ecosystem, even with small changes to a river. If you where to use solarcells and windwills, I would be all for the idea, but I think it is completely irresponable to build you own hydropowerplant, without taking extreme care i respect to the environment. Imagen if everyone who lived by a river build these things, that would be extremely destructive.

Re:Legal ? (4, Insightful)

gleekmonkey (737957) | more than 10 years ago | (#8832067)

How is it more 'irresponable' to use water as a source of energy rather than wind or sunlight? I wasn't under the impression that waterwheels were perticularly damaging to the environment.

On the positive side, if everyone by a river did build one of these things, there would be less need for coal powerplants - THOSE are destructive to the environment.

A Waterwheel (1)

supradave (623574) | more than 10 years ago | (#8831984)

The only method would be to build a flume and a waterwheel. Start the flume high up-river and then direct it to a waterwheel. That would give you enough flow to get the waterwheel turning.

Of course, I don't see why couldn't just make a waterwheel that could lift enough water to keep it turning without any additional water.

Permits? (4, Interesting)

pherris (314792) | more than 10 years ago | (#8831987)

While it does sound like an interesting idea I suspect that the county and/or commonwealth will want you to pull somekind of permit. After they stall you for a year or two just to come up with the regulations they most likely want engineering data concerning possible damage to the riverbed and the generator's effect on river currents. Of course this really makes no sense but local politics never did.

Years ago my family spent a few years trying to get a 30' fix pier (that others on our street could use for free) built by our property. Between the hassles of the town, state and MEPA we gave up. Strangely a few years later a neighbor (and state senator) who opposed to our project build his own from our prints 100' away. I guess we didn't grease the right gears.

My advice, make it small, discrete, quite and easily removable. Be forward that running your own generator over a long period is probable cause for the DEA to search your house as a suspected grow-op. It sounds crazy but again it's all about politics.

Bonne Chance.

I forget the name of it now.... (5, Informative)

zogger (617870) | more than 10 years ago | (#8831993)

... but there exists a tow-behind your sailboat generator I have seen. Looks like a dinky torpedo that is trailed behind, the little props spin, you get juice. It would do what you are looking for, easy to install, some power. Legalities of tying it directly to some point out in the stream-no idea, plus the safety factor of someone smacking into it.

found it

with that said, unless a stream goes entirely through your property, ie you can control both sides of the bank and build a proper dam etc, which is a ton of hassle and permits and whatnot usually, I would recommend doing the normal tried and true approach of wind/solar/fuel genny hybrid as an adjunct to your grid power. Re arrange where you put your money into first which of the first two works better for your locale. You usually want all four for true backup solution in most places. that is a generalization, but mostly true. It's really a variable, it has to be customized to your location and needs. Site survey maps exist on the web that will show mean average sun shiney hours and mean average winds for your area that will help you make a determination of which method gets priority. the reason why the "hybrid" approach is so good is that usually most places in the US get a lot of wind in the winter, but less wind but more sun in the summer. but that just depends, some places it's so windy all the time wind alone with the fuel genny backup is good, other places solar is better,etc--just depends..

me = grid, some solar, backup aero-marine wind genny, two fuel gennys

good luck! Once you get your rig up and working, you'll ask yourself "why the heck didn't I do this years ago?" It's really comforting knowing you always have SOME power no matter what, and even better to OWN it.

how do you sync to the grid? (1)

frovingslosh (582462) | more than 10 years ago | (#8831994)

Let me ask a follow-up question to this. If one were to generate power this way and stay on the grid to try to feed back power and mak some income (as well as have power if your system greaks down), how do you keep your river driven system in sync with the 60 cycle grid (which obviously must be done if you plan on feeding the frid)?

Re:how do you sync to the grid? (1)

MrChuck (14227) | more than 10 years ago | (#8832072)

An inverter/controller?
The same way you generate (and feed power onto the grid) from ANY AC (alternator created) source like windmills and most other none Solar/PV sources (which make DC and are inverted into AC and fed onto the grid all over the place).

Re:how do you sync to the grid? (0)

Anonymous Coward | more than 10 years ago | (#8832115)

You use a synchronous generator! It is self-synchronizing to the grid. However, since this is the case, sometimes the grid will need to supply you with power if you start drifting. It is not so simple.

I suggest: if you don't know what "reactive power" is, you *should not* be hooking things up to the grid. Hire an engineer to do it all for you.

Two way Meters (1)

Dark Bard (627623) | more than 10 years ago | (#8832125)

Most companies that sell wind generators and such have equipment for generating 60 cycle AC current. Check with the power company for two way meters. They allow you flow power back into the grid and keep track of whether you are providing more than you are taking. You may not get much money per watt for what you are selling back but the big thing is you don't need battery back up. A huge savings and far less maintence. You'll need an electrician to do the hook up and sync you to the grid.

Re:how do you sync to the grid? (1)

!3ren (686818) | more than 10 years ago | (#8832128)

Convert to DC, feed through an voltage controlled oscillator with a phase-locked loop and an amplifier. tada

what about a fish-like device (1)

polished look 2 (662705) | more than 10 years ago | (#8831996)

what about building some kind of water-wing that, when placed in the water, oscillates from low position in the water to high position in the water - then somehow pull energy in off of that.

I'm surprised nobody suggested this (2, Funny)

unixwin (569813) | more than 10 years ago | (#8831998)

well here goes -- move

Is your land hilly? (1, Interesting)

WindBourne (631190) | more than 10 years ago | (#8832000)

One thing that you can do is use a small hydraluc ram to move water up a hill. Once in a small, resivoir you then allow gravity to do its work. Nice thing about this approach, is that if you use a big enough pipe/ram, you can pump up enough water for using on other projects such as irrigation or a simple open flowing water stream.

And for many here, the ram does not use electricity.

Re:Is your land hilly? (1)

cK-Gunslinger (443452) | more than 10 years ago | (#8832126)

Windbourne, in this house, we obey the laws of thermodynamics! []

The Standard Way to Do This... (2, Interesting)

nightwing2000 (539158) | more than 10 years ago | (#8832022)

Which is also unobtrusive, is a turbine that looks like a jet engine. A tube with a series of fans inside; if the current is decently fast, it will turn enough to create electricity. If the current is not fast enough, then you don't get eanything.

Unfortunately, making a long-term sealed generator and submersible it is probably not a home project. I suppose it also depends on what sort of stuff coming down the river might eventually plug the rotors. But at least it would be submerged and hidden. As long as it does not impact river navigability (and you don't chew up a few swimmers with the blades, ha ha) who's going to notice and complain?

If you don't actually have a drop, the usual waterwheel, dam, etc. solutions won't work. You could try that Roman trick, if you are allowed to moor a barge in the river; put a big paddlewheel in the barge; hook it to a bunch of auto alternators, and get some power inverters?

If you had the paddlewheels mounted in the center of the barge and enclosed in an insulated deckhouse and turning all the time, probably (?) they would not freeze. (Just HOW cold does it get there? Flowing water, of course is never below zero...)

Old Mother Earth News backissues.. (1)

itomato (91092) | more than 10 years ago | (#8832026)

Check your local library's collection of 70's Back-to-the-land books. I know there are some principles laid out in one or more of the Foxfire books. A good book if you can find it is called "Making Do". There are great diagrams in there for elegant and simple, lo-tech solutions to issues like hydro-power, cooking, etc.

Mother's run dozens of articles on the subject through the years. Do they have a CDROM/DVD archive yet, anybody? That would friggin rock..

Mother archive (1)

itomato (91092) | more than 10 years ago | (#8832080)

Oh yes.. Mother Earth News [] CDROM archive. Glee. No word on what the 2400 articles contain, though..

submerible generator (4, Informative)

SuperBanana (662181) | more than 10 years ago | (#8832027)

Real Goods catalog sells a generator that looks like a boat trolling motor or a minisub thruster, only with a bigger propeller. You anchor it in the river, and it uses the large volume of water flowing past it. I believe the river still needs to be moving at several feet per second, and has to be at least 2 feet deep- we're not talking mountain stream here. Needs to be a -river-.

The other way is to lay pipe along the river for quite some distance, to as low a point as possible. You need quite a bit of "head"(vertical delta) or a lot of waterflow; Real Goods' other generator system uses a turbine, with a customizable configuration of nozzles.

As for selling electricity back to the grid (aka intertie systems)- you can't always do that(ie, "sell" the electricity back), and even if you can, there are often limits on how much electricity can be generated. The power companies also get pretty pissy about people powering the grid, because if there's an outage, and a lineman goes to work on the lines he thinks are dead...well...fried lineman. Most inverters these days designed for intertie(which is what we're talking about) have safety features to prevent it from powering a grid by itself, but power companies still like to make excuses and may demand one of their engineers check out the system(at your cost of course). is not a valid source of info (0)

Anonymous Coward | more than 10 years ago | (#8832058)

"Rumsfeld Lying Through His Teeth [] "

Of course they would say that. is a branch of the Democratic Party campaign apparatus. They would claim that Rumsfield is a dirty rotten scoundrel whether or not he lied: just because Rumsfeld is in the other party.

It is like having a sig saying "Clinton is a Slick Scoundrel []." That someone says bad things about their foe like this is neither newsworthy or proufound.

Getting energy from the river. Some ideas (4, Funny)

AtariAmarok (451306) | more than 10 years ago | (#8832038)

Sneak out and clamp 12 to 120 volt convertors on passing motorboats, with wires going back to your house. The wires had better be long

Stand on the shore with a big shotgun, and demand that passersby pay you a toll in killowatt hours in order to pass.

Provide all the catfish with treadmills connected to generators.

Per Max Screck [] of Batman 2, set up your own power plant and connect to the nearby hydro plants. Provide a lot of paperwork that no one reads, that includes the part that says that your power plant actually drains power from the grid instead of adding to it.

Power hot air turbines from meetings of the Susquehanna River Basin Commission. []

If all else fails, I'm sure that the orgone writings of Reich, the magic energy fields of Tesla, or the spoonbending force of Uri Gellar will give you an answer.

The easy way. (0)

Anonymous Coward | more than 10 years ago | (#8832042)

Instead of generating electricity use to water to bathe in. Once you have developed a stronger immune system you can move on to using the river for drinking water. Just leave the lights on

Is there an elevation change involved? (3, Informative)

StateOfTheUnion (762194) | more than 10 years ago | (#8832046)

If your relying strictly on the flow of the water (no gravitational potential energy due to elecation changes) you can measure the speed of the river flow get some idea how much head pressure the river can deliver. If it's a slow moving river (as you said in the header of the post) there may not be a lot of pressure head to deal with (which would imply a large volume of water to generate significant current).

Start with conservation (5, Informative)

danharan (714822) | more than 10 years ago | (#8832047)

Seriously, almost any solution will cost more than conservation. Not only can you have a smaller generator, but you won't need as many batteries to store energy for peak periods.

Check out real goods [] and other suppliers. Good lighting, gas-powered hot water heaters, fridges and cooking... there are lots of nice appliances that can reduce your reliance on electricity.

As for generation- keep your options open. It may not be legal for you to install a micro-hydro generator, and solar or wind might be cheaper.

I'm suspecting... (1) (257083) | more than 10 years ago | (#8832049)

... there are a lot of very interesting, new ways to place impellers, and energy transferance devices into the waterflow, which, just being moved by the motion of the river, will power a turbine... ???? .... profit, er, I mean, electricity.

the need to divert a water flow seems really really labor intensive, and also, very 19th century.

This is /. right? theres got to be something cool in the archive about innovative hydrodynamic power systems.

Jack Rabbit (1)

theparanoidcynic (705438) | more than 10 years ago | (#8832059)

This thing [] is the only applicable product that I've ever seen.

My father had a book on this stuff (5, Informative)

panurge (573432) | more than 10 years ago | (#8832063)

It was obviously written for settlers in the early 20th century and had all kinds of stuff on the different types of paddlewheels for different applications. By the sound of it you would need an undershot wheel with large buckets, unfortunately far from unobtrusive. Noise could be a major problem unless you used sucessive belt step-up drives rather than gearing, but the basic setup would need to resemble an automotive alternator system, which can produce a fairly constant output power despite fluctuations in rpm.

However, there would be many potential problems, especially the difficulty and cost of fixing a large overhung wheel with an asymmetric load over a river with fluctuating height (the wheel axis is going to need to rise and fall) and the regulatory problems: I guess you would need a license and it might be hard to obtain.

Another solution might be a hydraulic ram. There is the remains of one near where I live, that could raise water nearly 200ft. without an external power source, and was very simple and reliable. I guess some sort of license would be needed, but they are unobtrusive- there is nothing to see above water level but the exit pipe and the compression tank. Once the water is in a storage tank at high level, it can power a conventional turbine or an overshot wheel (more efficient than undershot), and the output can be adjusted to give fairly constant generator rpm regardless of load. Hydraulic rams can be noisy.

However, I wouldn't recommend going down either of these routes unless you are a qualified mechanical or civil (structural) engineer or both, and have good contacts in other disciplines.

The smallest hydro generator I have seen working, by the way, is at the end of the River Lyn in England. It's way bigger than you are likely to want ( I think I recall it's about 100KW) but when I was there in the early 90s it was still working. It attracts a lot of visitors from the US, and the whole place (including the water powered gravity railway) is a wonderful example of English quaintness.

Wrong (0)

Anonymous Coward | more than 10 years ago | (#8832070)

No. You're an idiot.

Re:Wrong (0)

Anonymous Coward | more than 10 years ago | (#8832087)

Well said! Furthermore, I agree.

Convert the river to youre needs. (2, Interesting)

NoMercy (105420) | more than 10 years ago | (#8832089)

Split the river, so next to the original you have a very very low gradient river channel, carrying the water down-stream with little loss of height, then let it out of a small channel, a lower volume of higher speed water, sutable for driving small generators, there's a old water-mill by a village near here which uses the system, wheels gone, but the jet of water is still there squirting out into the lower part of the river.

check your regs first... (5, Informative)

waytoomuchcoffee (263275) | more than 10 years ago | (#8832091)

You have Federal, State, and local regs you need to check out.

First, Federal. The Corps of Engineers handles 404 permits. You need this to discharge dredged or fill material into waters of the United States - fill material includes structures as well. You might be exempt (usually if you affect under 1/10 acre you will be), but you need to make sure. If you are going to affect any Federal Endangered/Threatened species (are any in/near the river?) you will need clearance through the US Fish and Wildlife Department and or National Marine Fisheries Service. This is usually coordinated through the Section 7 process of your 404 permit, but if you DON'T qualify for a 404 permit and there are endangered species, you have to do your own Habitat Conservation Plan and prepare a document under the National Environmental Quality Act (NEPA).

Second, State. The Pennsylvania Fish and Boat Commission regulates fish movements. "No dams, ponds, or other devices which prevent free migration of fish shall be erected or placed by a person licensed to propagate and sell fish in a stream flowing over the person's property".
I am sure you also have some type of dam safety office as well, if you go that route. Also, I don't know how water rights work in your state, but you need to check into that as well. You also might have a state version of NEPA (many states do).

Third, local. Check your local Planning department for applicable rules and regs.

Stupid question (0)

Anonymous Coward | more than 10 years ago | (#8832106)

This is an inane request. Instead of going into cardiac arrest when the power goes out, learn to live without your computer. Candles and a gas stove are cheaper than the lawyers it'd take you to get the permits to do something like this, and they cause far less ecological damage than someone who has essentially no clue would stand to cause digging around a river.

If you have a legit reason why you need power(think dialysis machine that you'll die without, not internet you'll go into withdrawl without), some combination of your town and power company will give you a generator.

Good thing(tm) (1)

CGP314 (672613) | more than 10 years ago | (#8832129)

From the make-sure-you-have-plenty-of-candles dept.

How very optimistic of you Michael

-Colin []

This is dangerous (0)

Anonymous Coward | more than 10 years ago | (#8832141)

Because of the frequency, living along high-current streams and rivers may fuck with your DNA. I would suggest the use of a tinfoil field dampener if you are planning on living near any EMF generating bodies of water. Lakes and ponds are cool though.
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