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Off Grid Via Slow Moving River?
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.
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.
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).
You woudn't happen to wear a 50's era bifocals and live in a van down by the river?
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.
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?
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.
"Glory is fleeting, but obscurity is forever." --Napoleon Bonaparte
Why not just use humans? Just make a computer based reality world to keep them happy, and harness the energy.
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.
... 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
http://www.salt-systems.com/marine-wind.htm
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.
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.
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.
Information: "I want to be anthropomorphized"
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.
Panurge has posted for the last time. Thanks for the positive moderations.
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.
I would suggest that hydro power is not the best way to go for an off grid home power system. You really need high volume/high head water source to harvest any appreciable energy; from what you've described, there is no appreciable head (vertical drop) to the river near you. As well, as others have pointed out, building anything in the water entails a lot of bureaucratic red tape.
I would say that solar or wind power is more feasible for most people. Solar is cheap in maintenance costs but expensive to set up, and you really need a lot of panel area to hope to supply your needs. Wind power is cheaper up front, but more maintenance is required because of moving parts, and noise from the rotors can be annoying.
Either solution will require a battery bank to store power to use when the plant is not producing, plus a good inverter to supply consistent 120v 60Hz power. If all you are looking for is protection from outages, the battery bank with a generator may be ideal from a cost/benefit perspective. The payback time of most alternative energy projects is in excess of 50 years, so think carefully before you invest.
I have a lot of experience maintaining a large bank of rolls/surrettes and some trojans ( and others). One, they'll last a lot longer than 5-6 years, especially is you install a desulphator on the battery bank. They *work* as advertised, I highly recommend them. I've actually rejuvenated some marginally rank batts with them. neat stuff, the gov and some industries use them a lot to, to keep starter batteries "fresh" for long unused storage conditions with vehicles that only get occassional use.
On the batts, the rolls are definetly good, and definetly expensive, along with the crowns. I have found cost comparing, it might be useful to check out local forklift companies and get a battery bank from them. These are deep cycle "traction" batteries in steel boxes. Whoppers, and with batts, it's the lead, the size, bigger is better more or less. You can get a 12 volt bank for around 6-800$ that will hold twice (roughly) as many amp hours as the equivalent-in-money rolls batts. Plus, if you are near any big city with the foirklift dealer, you can go get the thing yourself,(heavy, be prepared for some egyptian engineering to get them in place with levers and ramps and dollies and whatnot) usually rolls batts need to be shipped in,too, kinda spensive...
the forklift batts come 12/24/ 36 / 48 volt so you can pick your voltage requirements. Most home systems are 24 or 12 volt at the storage, depends on how far away your panels are, and how much thick expensive copper wire you want to run. You can (if you really want to) CAREFULLY cut the welded busbars on the top of the forklift batts and do your own custom series/parallel wiring as well,to get whatever voltage you want (say knocking down the 48 to a 24) but I'd recommend just sizing for your needs and purchasing appropriately.
Good luck!
Assuming you mean the Susquehana River in Pennsylvania, you have to deal with DEP permits. A quick glance at the regs indicated you'd need
a) Dam Permit - application fee of $1500-$3000
b) Environmental Assessment Approval - free
c) Limited Power Permit for Hydroelectric - $5 application fee and $10-10000 annual fee (depending on capacity)
Not to mention any local or federal regulations (did you check the EPA yet?) or the permits you'll need for construction, etc.
There's also a 30-day public comment period before the DEP rules, and they estimate it will take 220 days or so to complete the paperwork.
Reference is from the massive PDF found at Department of Enviromental Protection
In short, you probably don't want to build a dam.
If you know of references that rebut the standard historical theory (wouldn't be the first time), please post links or titles. I'd want to read them
Anyway, it's my understanding that water mills began serious development during the "Middle Ages". Modern Western culture is descended from the great cultural renaissance of the 15th century, and we've inherited their prejudice against the "Middle Ages", that 1000-year period after the fall of Rome where Western progress supposedly ground to a halt. But this period was when people started playing with technology seriously, and thinking about ways to use it to make life easier -- and to get rich. In short, it was the period that gave birth to the techno-geek!
do cats know to keep the fish out? And do they work in shifts or what??
Some work in shifts. A few work in loincloths, but most wear the catsuits they were born with.
Don't blame Durga. I voted for Centauri.
Nobody is taking free energy from anywhere.
The Sun's energy was used to evaporate the water, which carried it up into the atmosphere, and then it rained down over high altitude. Water at altitude has potential energy, equal to g times the height times the mass - this is the energy that is used for hydroelectric power.
The dam uses the potential energy difference between the water at the top of the dam, and the water at a bottom of the dam. Nothing more. When water is released at the top, this potential energy turns into kinetic energy, which is used to run generators.
Where there is NOT a dam, this potential energy is used to accelerate the water (which is why rapids move fast, while dammed rivers don't!)
So as long as the guy's private energy generation doesn't sink the water level behind the large dam (pretty unlikely) he isn't taking any of the energy that the hydroelectric plant uses. He is simply slowing the flow of water in his section of the river marginally.
Finally "Where does gravity get its power?" Power is energy per second, and since gravity doesn't have any energy as such, nor does it have power. Gravity is simply a force, and by counteracting this force we can store potential energy, but that is exactly the same energy that comes back. Remember that current theory is that all matter started at the same point, so any energy that is created by objects in the universe falling towards one another is really just the return of the energy once used to pull them apart. If you are asking where the gravity get its force, well, that is a deeper question for which we would have to leave 7th grade physics.
yes, but just momentarily
Huh? Let's not forget the law of conservation of energy. Of course a waterwheel/generator takes energy from the river as it puts out electrical energy. There is nothing "momentary" about it.
But this energy is otherwise "lost" to heat as the water flows downstream anyway. IIRC it was Joule (whose energy scale we use today) that originally did the science on waterfalls, showing the water temerature at the bottom of the falls is higher than at the top. As water flows downhill, it pummels into itself, and the gravitation potenital energy is converted to heat.
A waterwheel simply takes some of this energy and converts it to rotation instead of heat. With a waterwheel in place, the temperature of the water will be ever-so-slightly cooler downstream.
The downstream reservoir has a level, and it is the difference between this elevation and the tailrace (water exit) elevation that determines the amount of energy the hydro plant can extract. The difference is called "head" (I kid you not).
So the energy of the water used by a waterwheel is not "stolen" from the downstream plant... because it would have already been "lost" to heat as it reached the reservoir anyway.
Anybody want a peanut?
That's freaking brilliant. I'm sure the massive gear and belt-driven factories that were the peak technology of the Industrial Revolution were designed by engineers that constantly thought to themselves, "what a disaster, I'm wasting 20% of this FREE ENERGY."
Sheesh.
Here's something that sounds just like what you're looking for:
In the east channel of the East River, next to Roosevelt Island and in the shadow of the largest power plant in NY State, Verdant Power has been deploying a small farm of low speed turbines to tap the force of the tidal stream that flows back and forth in the channel.
In the scale you're interested in, a ten foot turbine can power 25 homes.
There is an article about it at the Roosevelt Island Wire website.
I don't know what the average flow of the Susquehanna is but I doubt it's really a slow river. I do know the Mississippi is typically moving about 4 knots and it is considered by boatmen to be an absolute bear to travel upstream. Recreational boating in the main Mississippi channel is near zero because the current's just too strong. I'm betting your river is faster.
A sailboat (monohull recreational boat big enough to have a galley) is making fair time if he averages six knots. Six knots is enough to generate a helluva lot of electricity using a water generator (they call them "spinners" and some of them will convert to wind generators if you get the urge). These things are not even that expensive.
Contrary to some of the alarmist nonsense being posted here, as long as you are not messing around in a wetland (swampy, boggy marshy place) and you don't propose to do any dredging, the Corps of Engineers presumes that all docks and piers for small boats will be approved for riparian use on ALL navigable waterways as long as you don't interfere with navigation. Possibly you have stronger local regulations, but get your COE permit and I think everything else will fall into place pretty easily. Sink a couple pilings, hang the spinners deep enough to keep from freezing and I expect you're in business.