Author Topic: Grid tie voltage? AC or DC?  (Read 15212 times)

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MAL

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Grid tie voltage? AC or DC?
« on: December 18, 2016, 02:00:59 AM »
I am just starting to work on a home brewed generator.  It will be use for hydro power with no batteries, I assume that AC will be a better choice with less hardware, and if that is correct should I build a 120 VAC generator to hook up to the grid tie inverter or would a more common voltage like 48 work better with more inverter options? 

SparWeb

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Re: Grid tie voltage? AC or DC?
« Reply #1 on: December 18, 2016, 11:41:11 AM »
Hi Mal,
First off, maybe fill us in on how well the hydro genny is coming along?
Just want an idea of what you've settled on doing, water resource you have available...
Last year you were just getting started - glad to see you back for more!
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MAL

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Re: Grid tie voltage? AC or DC?
« Reply #2 on: December 18, 2016, 02:18:17 PM »
Hello SparWeb,

I am just starting to order parts for the generator I have read through all of DanB's posts(twice) and many more.  I am finding very little information on grid tied generators.

My water source is a very large slow moving river.  I plan to make a floating water wheel that can easily be multiplied for more torque as needed.

The generator will probably have 18" rotors.  Magnets and winding's are yet to be determined because I am struggling with voltage options.   I am leaning towards AC and higher voltage, but I am not sure about the pros and cons.

I suppose my self imposed challenge is to do this as cost effective as possible. The inverter is one of the big hurdles in this challenge and I don't think one of those Charge Angels on Ebay is an option...but they are cheap. 

Am I headed in the right direction with AC and higher voltage?





george65

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Re: Grid tie voltage? AC or DC?
« Reply #3 on: December 18, 2016, 08:19:30 PM »

Given the parameters  you have specified:

Virtually unlimited water source,  Floating waterwheel
Cost effective,
AC,
Grid tie

What about saving yourself the trouble and expense of building a generator and use an induction Motor?
With the right size waterwheel made from a barrel or something similar that is cheap and large to give you lots of torque,  You could easily run something like an automotive serpentine belt around the drum and onto the pulley of the motor to take advantage of the torque to give you the speed to drive the motor. IF you get the right type of 3 phase motor you would only need to drive it under 1000 RPM. You Can make the wheel Big enough to give you the torque and have virtually unlimited gearing ability to make the thing run fast as you want from there.

You can grid tie the thing with all the safety controls in place by simply rectifying the AC output to DC with a 3 Phase ( or single phase) rectifier and feed it into a solar Inverter.  This will do all the phase and voltage matching and stop the motor consuming instead of generating if the speed of the river  drops or whatever.

I have a setup like this driven by a small Diesel engine and it definitely works.  Allow about 50% of the motors rating for practical generation. IE, if the motor is 5000W rated, count on 2500W max generation.  You can get a bit more but you'll start pushing the voltage too high for the excitement caps.

I'm wondering if it is possible to make an induction motor controller with an arduino that has a voltage sensor and uses PWM on the capacitance to control the output of the motor? Sound reasonable in theroy but I'm wondering if you can PWM Capacitance in the first place?  All the controllers I have seen for IMAG's so far basically run the things flat out and use a diversionary dump load to keep the main load on song. This would be great both as a load and a speed control in this case. If the river gets too fast the controller feeds in more capacitance creating more resistance ( and current) and slows the thing down.

Anyway, for what you want, this would seem to be a reliable, cheap, fast and easy way to go. All you would have to electrically do is wire in the caps and the rectifier and hook it all together.  3 phase motors are cheap as Chips and generally have good IP ratings for the damp climate it will be used in and a used Solar controller can be picked up cheap and easy as well.

If you are looking for a project to build the generator and controller yourself, then I guess this is all irrelevant. If you are looking for a way to make power quick, easy, reliably and cheap ,  perhaps there is something here worth considering?

MAL

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Re: Grid tie voltage? AC or DC?
« Reply #4 on: December 18, 2016, 09:48:13 PM »
Thanks George,

I have heard of using induction motors, but I did had to google it to see what's involved in converting one to generate power.  I will look into that more.  The video that I watched involved rewinding the motor.  If that is the normal procedure it looks somewhat involved with a steep learning curve.  If you can elaborate on that some I would appreciate it.

I would like to steer this back to my original question.  No matter what type of generator I use,  Why do I need to rectify the power to DC?  DanB has built a few grid tied machines that he has posted on this site...unless I am mistaken they were higher voltage machines (100VAC I think).  I have seen AC to AC grid tie inverters.  I don't know much about them or if they are UL listed for net metering.  Are the cheap solar inverters UL listed?

SparWeb

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Re: Grid tie voltage? AC or DC?
« Reply #5 on: December 18, 2016, 10:06:53 PM »
Hi MAL,
I don't know what the Charge Angel is, but if you're referring to cheap stuff on e-bay, I would be very skeptical.

The trick with grid-tying anything is that you now make an interface with a corporation.  If you don't do it with their permission then you face risks of being cut-off from your utility supplier, or if something goes wrong, the blame for it.  This leads most grid-tied installations to be on the expensive side, to buy the approved equipment.   When DIY generators are involved, there has to be an acceptable disconnect and power management system on your end before the utility company will allow you to throw the switch.

An example of a successful DIY wind set up posted on the forum today is Kitestrings, who invested in a set of Classic MPPT Charge controllers to make it work, but steered AWAY from grid tie, and has no such plans AFAIK.  Kitestrings generates enough excess power that it might (barely) be worthwhile to grid-tie.  I'm in a similar condition.  In fact, I have an inverter that does meet the grid-tie requirements should I choose to use them.  But I don't.  It's just a bureaucratic hassle for 5 bucks a month.  That should give you a hint that grid tie imposes limitations that even the more advanced DIY'ers don't want to tangle with.

So that gets the political BS out of the way.

I hope that helps you make your choice.  If you're not interested in collecting batteries (who is, really?) then you do have other options:  water heat  or space heat is a good one, especially if your hydro resource rises and falls with the seasons (in the right direction).

Tell me what you want the power for.  Then I (and the others here) can help you with how to do that.

Converting induction motors is one way to make a generator, but hardly the only way!  Look at this and tell me if you're interested:  www.sparweb.ca
« Last Edit: December 18, 2016, 10:11:09 PM by SparWeb »
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MAL

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Re: Grid tie voltage? AC or DC?
« Reply #6 on: December 19, 2016, 12:39:39 AM »
I think the Charger Angel is the seller on Ebay.  The units that I was looking at are labeled Power Inverter.

 I am under no illusion that a grid tie is without hassle and expense, and it may well be a deal killer.  I am currently connected to the grid and I am not sure what I will gain by disconnecting. I cannot disconnect completely, three month out of the year there is ice on the river... so heating water would be great, but not when I need the heat the most. The other 9 months of the year I have constant flow of water 24/7 

As far as what I want the power for...I guess my dream would be #1 to generate my own power and be more self sufficient  #2 a check of any kind from the power company would bring a tear of joy to my eyes #3 ...well the third phase of my dream is not yet developed, but I would like to produce something with the electricity to generate residual income.   

I could be talked out of a Grid tie.  A grid tie seems to simplify the entire building process, cut cost, no losses to the dump load, maintenance and  electronic hardware that I don't yet completely understand.  Right now I can't even decide on what voltage to use.

I could be interested in induction motors.  Would it increase the size of the water wheel?  The wheel needs to be taken out of the river in the winter.

 

DamonHD

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Re: Grid tie voltage? AC or DC?
« Reply #7 on: December 19, 2016, 02:16:45 AM »
I have a grid-tie PV and a tiny non-tied PV system.  The grid-tie system collects enough energy that it could cover all my use if I went all-electric (it covers twice our electricity use).  The batteries to carry the energy would cost about the same as the house because most of the energy arrives when I have least need of it.

I agree with SparWeb's points and all the grid-tie stuff is expensive and certified and installed by grown-ups also with the right certificates.

My off-grid and grid-tie systems don't touch.

Rgds

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mab

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Re: Grid tie voltage? AC or DC?
« Reply #8 on: December 19, 2016, 02:36:06 PM »
another question: how far is your generator from your house? if it's a good distance then you should generate at high voltage as low voltage doesn't travel well.

ac or dc? I'd opt for AC if there's a choice as it's easier to convert ac to different voltages with transformers, and easy to convert to dc for that matter.

if you're thinking off-grid direct water heating then high voltage ac allows the use of standard water heating elements and standard switches, but you will need some form of control.

MAL

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Re: Grid tie voltage? AC or DC?
« Reply #9 on: December 19, 2016, 02:47:47 PM »
Hi Damon,

I agree with SparWeb also.  I am a contractor...I have electricians that sub contract for me.  I have found that sometimes doing it right does not always mean spending more money. 

I can see some benefits to a separate system.  So I guess the new plan will be to design a separate system that leaves me the option to grid tie in the future if it looks beneficial.

So if I design a system with a dump load instead of batteries, is it better to rectify to DC or is it possible to just use AC?  I can understand if there is a battery bank that DC is necessary, but is it the best option without a battery bank?

DamonHD

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Re: Grid tie voltage? AC or DC?
« Reply #10 on: December 19, 2016, 03:27:17 PM »
If the AC is not too wild then you may have extra options to control it easily with triacs and so on compared to DC.

But I think the details are important here.

Rgds

Damon
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MAL

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Re: Grid tie voltage? AC or DC?
« Reply #11 on: December 19, 2016, 05:04:00 PM »
Hello Mab,

The generator will be about 150' or 45 meters from the house maybe a little more.

I don't really like the Idea of dumping unused electricity into a bucket of water...kinda like not eating all of the food on your plate...but if it can get me up and running...

Do you have any opinion how high the voltage?  Does 120VAC make sense, or am I not in touch with reality?   

 

MAL

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Re: Grid tie voltage? AC or DC?
« Reply #12 on: December 19, 2016, 05:39:46 PM »
Hi Damon,

By too wild, are we talking about sine wave or voltage spikes?  The current in the river doesn't change that much or very quickly.  In extreme conditions it could range from 3-13 MPH.  So the potential is there for some fluctuation, or a log stopping it abruptly. 

Are the details your referring to in the generator, like resistance in the coils, magnet spacing...in other words a good sine wave?

SparWeb

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Re: Grid tie voltage? AC or DC?
« Reply #13 on: December 19, 2016, 08:55:13 PM »
A definition, to help you get started:
"Wild AC" refers to any alternating current that is not REGULATED in some way.  You're first guess about the wave form not being a perfect sine is one case, but there are other reasons, too.  Either in voltage, or frequency, or both...  what we are referring to is the variable nature of any of these variables.  The AC from the utility is anything but wild: frequency managed down to +/- 1% and voltage clamped to +/- 15% and anything beyond that can cause a disconnect from the system.  And it's a very pure sine too.  When you run a variable-speed generator (wind/hydro) then the output frequency is variable, the voltage tends to ramp up with the speed, and when connecting through rectifiers the waveform gets blocky.  Hence we call it "wild AC" and it has to be treated appropriately.

Getting back to grid-tie... clearly now the output of any generator, if it is to be tied to the grid, must be fixed in speed, and must accept that its operating voltage be clamped, too - and be able to produce useful amounts of electricity under those conditions.  You have just made a constraint that is much harder to make compatible with the variable water flow of 3-13 MPH.


And some economics:
To make a buck on grid-tie, you have to get your investment back from the utility.  Spending 8k$ to get a 0.95$ bonus on my bill is not going to get me started.  So let's scale your dream system, if we can:  Start with the assumption that you pay 0.10$ per kWhr of electricity you buy from the utility, and that they are ALSO going to pay you 0.10$ for every kWhr you generate and sell back.  Two SEPARATE assumptions that are NOT TRUE in many jurisdictions that I can name because I live in one of them!  Note that your utility may also be charging you additional fees per kWhr for other things like administration, distribution, and system upgrades, which on my bill are GREATER than the cost of electricity itself.  Also assume that your utility will charge you (I said CHARGE YOU) 25 dollars per month for the PRIVILEGE of selling them your electricity.  You know where this is headed already, right?  Next, we also assume you have a typical north american home, which is at least 10 MWhr per year.  You sign a contract with the utility that allows you to sell back to the grid your generation, up to the quantity that you consume.  They probably won't reimburse you for any production over your actual consumption, but that also varies in some jurisdictions.  Let's say you invest 10,000$ on a 10 kW PV array for your house, which will produce about 10 MWhr where you live.  You think this is balanced.  Now the awful math:

Consumption:  10,000 kWhr * 0.10$ / kWhr = 1000$ per year
Admin fees: 10,000 kWhr * 0.15$ / kWhr = 1500$ per year
Tie-In Fees:   25$ / month * 12 months = 300$ per year
Production:     10,000 kWhr * 0.10$ / kWhr = 1000$ per year rebate

So you're still paying 1800$ per year instead of 2800$ per year.  And if you had an exceptionally sunny year, you don't get any rebate for the extra production because it's capped at equal to your consumption anyway.  You will not get your 10k$ back if your utility company plays by these rules.  You have to find out for yourself if that's the case where you live.

There ARE jurisdictions that gave you a break, or give you a better price for PV electricity than the going rate for the utility's electricity, and that makes a big difference if you can get it (ask DamonHD).  However, many of those states/provinces are getting hammered politically and the gravy is about to dry up.
No one believes the theory except the one who developed it. Everyone believes the experiment except the one who ran it.
System spec: 135w BP multicrystalline panels, Xantrex C40, DIY 10ft (3m) diameter wind turbine, Tri-Star TS60, 800AH x 24V AGM Battery, Xantrex SW4024
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MAL

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Re: Grid tie voltage? AC or DC?
« Reply #14 on: December 19, 2016, 11:12:18 PM »
Hi SparWeb,

I appreciate all the hard work that you put into that.  In a previous post I already decided to not hook up to the grid.   I am/was not dead set on grid tie.  If I thought I could do it better than the power company than I would want to go off grid all together.

Do you have any thoughts about desired voltage?

...and WOW!  the work that you put into those motors is incredible.  I just had some time to look at your site and check it out.  I don't have the skills or tools to do something like that.  I have seen a few conversions on youtube that have cylinder shaped magnets drilled into the rotor, but it looks like planning something like that would take me another year to learn.  I am just getting to the point where I have some working knowledge of the Axle Flux.  I do see how it could have less expense, so I am interested, but I am not sure where to start, and so much of what I read here is like a different language. 

I suppose I could understand electricity better if I could see it, but when you see it, it's usually a bad thing. ;D

MAL

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Re: Grid tie voltage? AC or DC?
« Reply #15 on: December 20, 2016, 12:30:48 AM »
Hi Damon,

You opened a can of worms when you mentioned triacs.   If There is a simple explanation  of how triacs are connected into the system I wouldn't mind reading about it.  Keep in mind that my visualization of the circuit starts with the 3 phase AC wire from the generator in my hand.  If it's too involved I understand.

DamonHD

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Re: Grid tie voltage? AC or DC?
« Reply #16 on: December 20, 2016, 07:58:02 AM »
Ah, but you might be confusing me with an expert, especially on triacs; prepare to be disappointed!

A nice thing about AC is that the voltage crosses zero regularly, and devices such as triacs turn off automatically at those zero crossings, so all you have to worry about doing is turning them on, and they handle quite a lot of power in quite a simple way.  The advantage of the zero crossing is also that arcing tends to stop more easily with AC and so switches and fuses can be smaller and cheaper.

Probably best to use your favourite search engine, and/or search on here, for terms such as "SCR" and "TRIAC" and even "IGBT" (I have never used an IGBT myself, so far...).

Rgds

Damon
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mab

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Re: Grid tie voltage? AC or DC?
« Reply #17 on: December 20, 2016, 02:00:14 PM »
Hi MAL,

150' is not too bad;  I'd say 12v was a no-no, 48v a tad low, 120v  is a fair choice at that distance. If you were going to grid-tie I'd say go higher as most GTI's can handle several 100's volts anyway, and higher volts means less cable loss & thinner, cheaper cable.

I wouldn't get too hung up on a specific voltage though - like my hydro (using an unmodified induction motor as a generator (capacitor excitation)) the voltage goes up at higher outputs and down at lower outputs - but as long as the voltage is high enough at high output powers your cable losses will be acceptable without having to buy heavy gauge, expensive cables.

if you're not grid-tie-ing: it sort of depends what you want to use the power for - heating water is simplest and perhaps a few direct-connected lights with the water heater stabilizing the generator output; but if you want to run fridge/freezer/lights/computers, then you're probably going to have to have some sort of 'private grid' using an inverter, battery and dump-load. The battery doesn't need to be anything special as it's just there to provide a stable voltage to the inverter and surge power to start the freezer etc. The inverter could be an old UPS depending of the amount of power needed.

MAL

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Re: Grid tie voltage? AC or DC?
« Reply #18 on: December 20, 2016, 10:41:17 PM »
Hi Mab,

That was a very clear answer that make complete sense to me and answers the original question about grid tie voltage.

I don't believe I will be tying into the grid, at least from the start.  I was considering it to be the easy way to harness the power, but maybe the easy way is not necessarily the best way.  It seems like the solar power guys tend to like to grid tie, but everybody else considers it a pact with the devil. 

All of the control options make my head spin.

What are some of the specs on your hydro generator?...Motor size, rpm, output...I am kinda interested in how you geared to get the necessary rpm.  Is it posted online somewhere?  I have spent all of my time reading about axle flux machines, started to order parts to build one, and now I am not sure it is the best way to generate cheap power.

 As far as what I want to use the power for...I want to completely power my home.  When you said the battery does't need to be anything special, you were still talking about a battery bank right? 

Bruce S

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Re: Grid tie voltage? AC or DC?
« Reply #19 on: December 21, 2016, 09:22:32 AM »
MAL;
I might be wrong, BUT I think mab, might be meaning that for your learning curve cheap-to-free batteries would be best for now.

Also, since you stated you would like to power your home completely. There are some things we'll be needing in order to better help.
Power needs? take a full inventory of what you currently use. Making notes about fridges, freezers, heaters (electric ), lights. The whole thing.
This will go a long way in deciding how much storage and production you will need to have available.
It will also help you in seeing just how much is really needed and where you can begin to conserve.
Conservation is the first and quickest way to pay yourself.
The UPS's are now pretty easy to come by, tho the smaller ones (less than 1500Va) can be misleading. I've found that once they are off grid power, they drop to MSW. The little Minuteman units do this. The better unit like APC, MGE, Eaton's are great units. The APCs tend to burn up batteries if they are left inside their cases.

Hope this helps
Bruce S
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MAL

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Re: Grid tie voltage? AC or DC?
« Reply #20 on: December 21, 2016, 03:02:27 PM »

I did say that I would like to power my home completely, but I have about 3 or 4 months per year that hydro is not practical(ice).

My home is small and it's all living space...no garage or shed near the house...I have no place to put batteries.  I am interested in battery-less options.  My goal is simplicity, low cost cheap energy so I can use more of it.  As it is I do battle over power bills.  I could conserve more, but I would be looking for a new wife.  Conservation is good, but It's not the point of the thread. 

My electrical appliances are:

A 1/2 HP 240V(It can be wired 120v if it is more efficient)
A 120v lift pump for the sewer.
A 240v on demand water heater(not very efficient)
Electric dryer
Washing machine
Furnace fan only (gas)
A small clock, radio, Cd, dvd player (under cabinet)
Two microwaves
A side by side fridge
A 120v cook top stove
A double oven 240v I think
two mini fridges (I fought to unplug two additional mini fridges)
A chest freezer
four ceiling fans
one exhaust fan
A small circulation fan on my fire place
Three TV's
66 total light bulbs, many are LED (some are candelabra...LED's look funny)
various chargers for phones and laptops.
And I want to add power to the dock on the beach
 

My usage for the last year is below.

                                 kwh
12/19/2016      1,275
11/16/2016      1,042
10/18/2016      959        
09/19/2016      1,090
08/18/2016      1,195   
07/20/2016      1,287   
06/20/2016      1,304   
05/19/2016      1,001      
04/20/2016      1,066   
03/22/2016      1,102   
02/22/2016      1,118   
01/21/2016      2,105   
12/17/2015      1,230      

DamonHD

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Re: Grid tie voltage? AC or DC?
« Reply #21 on: December 21, 2016, 04:06:04 PM »
Conservation is essential if you want to make any inroads on powering your home with renewables from your own property.  We take energy on tap for granted!

Your monthly consumption is similar-ish to my annual consumption, for my family of 4.

By conservation I made it *possible* to more than cover consumption with generation over the course of a year; there simply isn't enough energy arriving at my plot of land (eg from the sun) without doing so, by a factor of 2.

So you'll see I've tracked in tedious detail what each appliance uses, and replaced them and lights and so on with more efficient versions over time, to get to my current position where I use about 1/3rd of the mains electricity and gas of the homes around me.

http://www.earth.org.uk/saving-electricity.html

http://www.superhomes.org.uk/superhomes/london-kingston-upon-thames-willingham-way/

To pick one item: with care I have managed to improve our kitchen lighting while bringing the the total consumption down to 40W (or 20W if you only need to sit at the table for example); probably less than a single one of your candelabra bulbs.

Sorry to sound like a smug git, but conservation is the very cheapest and easiest form of off-grid energy!  B^>

Rgds

Damon
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mab

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Re: Grid tie voltage? AC or DC?
« Reply #22 on: December 21, 2016, 04:31:53 PM »
hmm, that's a LOT of power to extract from a slow moving river! 1000kwh/month is around 1400watts. I'd be tempted to see what you can actually generate 1st, then consider how best to use it.

Mine is a small pelton wheel based system (high pressure - low flow); with 70' head (~34psi) and the smallest pelton wheel I could find - it spins the motor at 8 or 900 rpm - a 4 pole 3phase induction motor generating (as i type) 350watts at 145v 34Hz AC. As you're going to have a very slow turning water wheel, I'd say the large-radius axial flux generator you were going for was a better option.

As for what I said about the battery:- partly what Bruce said, but also was thinking: - unlike a solar based system where the battery has to support the full load from dusk 'til dawn and therefore needs to be large and deep-cycle capable - on a hydro-based system the power is coming in 24/7 so you can get away with a smaller battery, and, if you are prepared to match your consumption to available power, the battery is seldom supporting a continuous load so a cheapy old car type battery would suffice.  Trouble is, you're talking about quite a big peak load from your house so if you went down the battery route it would need to be a fairly big battery - even assuming you can achieve a 1400w+ output from you wheel.

As Damon says  - conservation is key. There are a few off grid people who run the house 'as normal' with spouse and kids, but as far as I know they typically have multiple Kw of solar AND of multiple kw of wind turbines AND (if available) hyrdo, AND they have a huge battery (and often a backup diesel generator for when they run short).

MAL

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Re: Grid tie voltage? AC or DC?
« Reply #23 on: December 21, 2016, 05:08:56 PM »
Hi Damon,

You don't sound Smug, I hope that nobody is reading any tone in my words that is not intended to be there.

I am all for conservation, but my wife likes to collect mini fridges and sleeps with the TV on etc...I walk around the house turning off lights, take a leak outside, mix concrete with river water, wear long johns and a sweatshirt in the house, I don't have air conditioning, I heat with wood, I have replaced the windows and doors, My home is built into the ground (berm home), I don't heat all of the rooms, I have done as much conservation as my wife will allow.  Do you have city water and sewer? I don't...those pumps are not cheap to run. 

I have a very different situation than you do.  I have enough water flowing past my house to power the city of London.  I only want to power one home and possibly use that power to work at home...with clean energy. My carbon foot print would be limited to the materials used to construct the generator.

MAL

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Re: Grid tie voltage? AC or DC?
« Reply #24 on: December 21, 2016, 05:48:05 PM »
Thanks Mab,

I think you understand my questions very well.  I had come to the conclusion that a large Axle Flux would serve my purpose,  but it doesn't take too much to make me question my thought process.  That is basically where I am at now.  I was very concerned that I would have a difficult time gearing up to almost  1000 rpm to run an induction motor, and doing what SparWeb is doing is out of my skill set.  I think that I am again settled on an Axle PMA and running higher voltage AC.  I am really trying to avoid Batteries.  I need to read more on heating water as a dump load with out batteries.  Grid tie may not even be an option...my state offers it to customers of the two major suppliers in the state, but I am in a small pocket of the state that is not supplied by either one of them.  So I don't know what that means, and it doesn't matter because I will not go that way unless I see that it's beneficial in the future.

Conservation is literally a daily fight...Are you a marriage counselor by chance? 

Warpspeed

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Re: Grid tie voltage? AC or DC?
« Reply #25 on: December 21, 2016, 05:58:12 PM »
Wow, 1,000Kwh to 2,000 Khh per month, i was going to suggest a few things, but its way out of my league.
My own consumption is about 100 Kwh per month in summer and 150Kwh per month in winter.

Your first priority should be to lower your consumption before you even start to think anything else. I managed to better than halve consumption by replacing some older appliances with something much more efficient.
Once that was achieved it all became so much easier.

Just a couple of examples, replacing an ancient  CRT computer monitor that ran most of the day and used 420 watts with an LCD computer monitor that uses 14 watts.

Replacing two motor driven wall clocks that each used 8 watts and ran 24 hours per day with battery wall clocks that use a 1.5 volt battery that lasts for over a year.

Its not difficult, it need not be expensive, and your lifestyle will not be any different.  But you can still live very well on far less power.

MAL

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Re: Grid tie voltage? AC or DC?
« Reply #26 on: December 21, 2016, 06:43:44 PM »
Hi Warpspeed,

My consumption is is just above average for the state that I live in.  I presume it is above average because I am rural...I have to pump my own water out of the ground and pump it out of the house when I am done with it.  I suppose I could take a dump out side...that could save me some more.  When I bought my fridge It said that It was energy star...Should I through it away And buy  a new one? I could spend $5000 on all new appliances and save $20 a month, but I have a hard time with the math on that one.
« Last Edit: December 21, 2016, 07:15:41 PM by MAL »

MAL

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Re: Grid tie voltage? AC or DC?
« Reply #27 on: December 21, 2016, 06:49:32 PM »
MY HUB AND SPINDLE JUST SHOWED UP!!!
« Last Edit: December 21, 2016, 10:10:27 PM by MAL »

MAL

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Re: Grid tie voltage? AC or DC?
« Reply #28 on: December 21, 2016, 07:10:58 PM »
I am sorry Warpspeed I shouldn't have snapped at you like that.  Nobody is more upset about my consumption than I am, but that is a fight that I cannot win.  I AM NOT JOKING!!!  My solution is to spend a couple thousand dollars on a generator instead of throwing away perfectly good appliances and fighting about why somebody left their charger plugged in.  look at the math a little bit.  I spent $1100 on my fridge when I bought it.  It works fine, but uses more electricity than the new ones.  I could buy a new one and have $1100 less to spend on a generator that would make my existing fridge almost free to run, plus my other appliances.  In my opinion it is better to spend money on the generator rather than on things that are not broken.  There is no doubt there are things that could help reduce consumption, but not without a fight with my wife.  My consumption is slightly above average where I live, but I would guess that it is below average for a rural home in my state.
« Last Edit: December 22, 2016, 12:57:11 AM by MAL »

SparWeb

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Re: Grid tie voltage? AC or DC?
« Reply #29 on: December 21, 2016, 10:34:55 PM »
Don't worry MAL,
We ain't judgin' ya!

Do what you can, within your budget, but we can tell you have some energy hogs running.
As for the energy consumption habits of your Chief Financial Officer... we aren't shareholders so we don't get a vote there either!
No one believes the theory except the one who developed it. Everyone believes the experiment except the one who ran it.
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MAL

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Re: Grid tie voltage? AC or DC?
« Reply #30 on: December 22, 2016, 02:29:20 AM »
Ya whatever... most "normal people" have some energy hogs. ::)

george65

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Re: Grid tie voltage? AC or DC?
« Reply #31 on: December 22, 2016, 03:51:01 AM »

Mate, I hear Ya!

I want a nice comfortable life as modest as it is. We use heaps of power here and I don't give a rats.  I generate my own and feed it back to the grid to use it like a battery and take it back when I want.
We put the heater on when we are cold, the AC on when we are hot, take showers till the hot water runs out, I leave lights on all night out the back for security and make no effort to save power that would impede our comfort.  I don't purposefully waste power, I just don't make any effort to put myself out to save it.  There's a difference between using something and wasting it.
I have no need to try and scrimp and scrounge as my bills are bugger all and the majority of the one I just got like all is " Supply Charge".

They charge me for selling me their product. Unreal.
Same with water. Don't try and "save " that either.  What we use is 1/3rd of our total bill. the rest is "Supply and drainage" charges.
Still trying to work out what we are trying to save water from anyway?  Hunger?  Extinction?  oppression??  Seems to me some people miss the insignificant point about there is always the same amount of water, it doesn't go away or get any more no matter how much you " Save".

You are going to need to aim to generate about 2Kw Hr which is a fair bit. You can do it, just need to make sure your water wheel and alternator are up to it. I'd over size both so the inefficiency's still leave you with what you want.  If you have an old style analogue spinny meter, back feed to the grid and use it as a battery for when you have the high demands. When you are not using much such as at night, you'll make headway.

 I Don't try to eliminate our bill, that will cause problems, just offset it enough so the $100 a quarter doesn't matter and I can still do everything I need.  The idea of running round making sure no one left an unused Phone charger plugged in or turning off the TV at the power point every time just leaves me cold. I couldn't stand to live like that although I do envy the people that have that as a concern in their life and nothing else or more significant to worry about.  So fortunate but probably still stressing over such piddling things.

I think you need to start crunching some real numbers before you go much further. Work out the speed of the river, the size of the wheel you are going to need to generate the power you want and then add 50% and build it.  No need to worry about dump loads or the like. Just turn the thing off when you have enough power and let it free wheel.

I suggest you don't try and reduce anything, go big to accommodate your needs and live comfortably.
Don't sweat the little stuff you have already then taken care of.

DamonHD

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Re: Grid tie voltage? AC or DC?
« Reply #32 on: December 22, 2016, 07:39:25 AM »
Hi,

There are consumer guides to help with deciding when different appliances should be replaced.

But as regards fridge/freezers a rule of thumb (IIRC) is that one over 10 years old should probably be replaced.  And not moved to the garage and run *in addition* to the new one!  For one house I know of I think *most* of their entire electricity consumption was found to be by the old and empty fridge that was sitting in the garage plugged in 'just in case'!

A plug-in consumption meter can tell you how much appliances are using over (say) a typical day, and you can look on line and see if new ones are significantly better.

Note that the EnergyStar ratings are a moving target as technology improves.

Rgds

Damon
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