wind and baseboard heaters

[meash]

I have been reading that some people have there generators setup that when the bats are full they send the excess power to base board heaters..

I would like to offset my heating costs buy using a wind generator to just power some base boards... I am assuming that a older baseboard heater would not really mind having a different freq besides 60 Hertz..

Best Regards

The toolmaker at play

[kilone]

Can you explain what you mean by base board heaters..

[Bruce S]

meash;

 The only problem with doing this, is to get the power up high enough to heat up the element in the heater. Even the oil filled units need a fairly high input at startup to get them heating. So unless you had something like 24 or 48 Vdc and 30amps delivered at the very startup the elements will not get even close to being warm.

This is the main reason most use them as a dump load. Once their batteries are fully charged they have the excess going to the heaters as they'll suck up just about anything thrown at them.

And you are correct with the freq. thing, so far the ones that I've tried will not care about it being 50/60hz. I would however, stay away from the really high freqs such as 200hz and such.

Hope this helps

Cheers

Bruce S

[Nando]

Base Heaters;

Most of them are resistive using the Vac of the country where the heater is located.

So most, if not all, Base Heaters may take DC, 50, 60, 200, 400 or even higher Hertz without any problem.

So, 115 Vac, 60 Hz for the USA, 220 Vac, 50 HZ for UK and so on.

Using the excess Mill energy, I think, should be done with a controller that has MPPT to harvest the highest energy possible from the mill.

12. 24 or 48 volts sources are too low for practical purposes and a very careful analysis is needed to determine what can be done to properly interconnect the mill power to the heater system.

One, may remember that the least the battery bank is cycle (up/down) longer the life is for the bank.

Wind Mill used for heating should have a controller that optimizes the power harvesting that implies that the controller needs to have MPPT capabilities and in addition, this controller needs to have an ELC ( Electronic Level Controller) to insure that the generated voltage does not goes above certain defined level, which at the same time insures Wind Mill RPM protection and this point should be just below the Furling point of the Wind Mill.

I hope that this helps.

Nando

[Random Guy]

Some Guy Wrote:

A FYI for everyone. Sorry, the post is wrong. Any power sent into a baseboard heater will be converted into heat. This is a basic law of physics. You just might not be able to feel it with your hand because the power level is so low. There is no "start up" for a resistive heater. Also, I seriously question that any frequency of AC you can generate with a windmill will have ANY effect on a resistive heater.

[meash]

Interesting, looks like I will have to look up some info on the  MPPT capabilities for the generator.  Im going to have 30mph winds at night for the rest of the winter so I was hoping to send the AC voltage directly to the heaters..

Would a heater element act as a direct short, stalling the generator?

The Toolmaker at Play

[nothing to lose]

That was very interesting Nando.

How ever I have electric base board heaters of the convection type also, not used at all  normally. These can be wired for 220Vac or 120Vac, when I did use one of them years ago I used it as a 110Vac on a 110Vac thermostat.

So heres the question.

 Normally you will not have the winds to get full power from a 1500Kw mill full time. If it goes over the 1500watts then it should be furling anyway.

It will be random power as the wind blows right. So if I just wire a mill of less than 1500watts direct to the heaters which are rated as 1500watts I think and just let it run as AC NOT converting it to DC then what? I would think even at 90Vac I would be getting heat from whatever watts I put to the heater, perhaps even lower volts right. Will 500watts from a mill give close to 500watts heat in such a case? Kinda simply a case of taking watts from the wind in the air and releasing it as watts of heat at the house floor? What ever watts is there is there, right?

Kinda what I been thinking about trying. Use one heater directly powered by the windgennie, the second heater on grid with the thermostat set about 65F. If the wind has been blowing good and the first heater working then the temps should be above 65F and the grid heater should not turn on. In a case of low winds perhaps both heaters would be working but the mill powered one should lower the load on the grid powered one.

Been thinking about this for when it's not quite cold enough for a wood fire but need a bit of heat anyway.

[Opera House]

Just some quick math for a 1,000W heater as the voltage drops:

120. V  8A   1000W
     
60. V   4A    240W
    
30. V   2A     60W
    
    

So for a a 24V system you will need about 20 heaters to get the same load.  At least you don't get that burning smell.

[monte350c]

Hi All,

A resistive type heating element will not really care if it's AC or DC going through it. For example, if you take one of the smallest resistive heaters in normal use AKA a 100 watt incandescent light bulb and put 110 volts ac rms through it, and then put 110 volts DC through it it will light up the same.

However, most baseboard electric heaters with built in thermostats may very well care about the incoming electricity. So you'll have to check to be sure the 'stat will be happy with the off-spec voltages.

OR...

What I am planning to do - the mill I'm now building will be a 24 volt machine. The output of the alternator will be recitifed and fed to a 24 volt battery bank consisting of 2 x 12 volt deep cycle batteries. Those will be at the pole, along with a 2500 watt modified sine (read cheap) inverter. The inverter will send 110 VAC up the wires to the house, where the load will be either baseboard heaters, or a water heater.

When the wind is blowing, the inverter and heaters will be on. When the wind is not blowing, the inverter and heaters will be off.

Gets around the 'wild AC' problem without adding too much in the way of cost or complication.

Ted.

[ghurd]

I love that plan!

What about inveter over/under voltage protection?  I'd be a little concerned the inverter would smoke from rapid cycling.

G-

[ghurd]

I believe Bruce means the startup of the windmill.

A connected resistive load is going to act like a short, and the blades will be very restricted, too much to get functioning properly.  It's almost like having a brake on, or having a lift machine act as a drag machine.

Until the blades get moving fast enough, ANY load will keep the mill from making much power.

It's not the physics of the watts vs BTU, thats a given.

It's the physics of the blades working enough to make any watts.

I have a 60~80W machine that will not even start to turn if an #1156 is connected direct.

G-

[monte350c]

Hi Ghurd,

I am planning to find an inverter that has an adjustable low voltage cutout point. So when the wind stops, the inverter will continue to run until it discharges the batteries down to the low voltage cutoff point, then turn off.

When the wind picks up again, once cut in speed is reached, the mill will start to charge the batteries. When the batteries get over the low voltage point, the inverter will start again.

I might do up a small circuit that is able to 'lie' to the inverter about the battery state of charge. Some hysterisis could be built in. For example, at 12.2 volts on the batteries, the circuit would inform the inverter the batteries are at 11 volts and it's time to cut off. Then at 13.2 volts, the circuit would tell the inverter the batteries are topped off and it's OK to resume operations.

The inverter and loads will be sized to the mill to make sure it always has more load than capacity. The hysterisis circuit and the load should avoid short cycling the inverter.

Another advantage is the mill will be seeing the batteries as a load, not the resistive heater so that will let the mill freewheel up to the cut in speed.

And later on if I decide to store some power all I have to do is add more batteries...

Ted.

[Shadow]

I have a heat element out of an electric furnace, I believe it was 240 volt. I have tried hooking it directly to my 48 volt dual rotor, which at the time was putting 60 volts/28.6 amps into 48 volt battery bank. I disconnected the batteries and connected the element, thinking the element would only 'absorb' the amount going into it. About the time I could feel and smell heat, I looked up and the turbine had slowed to a crawl, eventually stopping.I unhooked the element and away it went up to speed. What I was wondering is, was that also heating up my stator? or just the element? I now use this element as a brake if I want to shut the mill down in high winds, slow it right down, then use the knife switch.Is this hard on the stator? I may try shortening the element to a lenght the mill may handle.

[ghurd]

See Shadow's comment below.

[ghurd]

That's almost too simple!

A $69 inverter and a $15 heater.

Now I love it even more.

The inverter could maybe be tricked with a big diode or 2 in series?

G-

(PS- I understand more of this than VAWT design. LOL.)

[monte350c]

Hi Ghurd,

I will be working away at this over the coming weeks. I really hope to finally have something in the air before X-mas. One of my biggest problems is I keep thinking of new ideas, which postpones the building of an actual unit.

I have decided to just run with my current thinking, and actually make and fly something. It will be a downwind, 2 KW, 14' diameter unit with the above mentioned loads attached to it.

I'll keep the board posted as this develops. Now back to building the 4 axis foam cutting machine. First that then the blades...

Ted.

[TomW]

G-;

In my experience most of the cheap inverters switch a low voltage to toggle power on and off so it sure seems you could trick out a method of sensing battery voltage and toggling a relay based on battery voltage? on at 11.5 off at 11.0 or somesuch. Just an idea. Depending on how much you care about the batteries you may want to let them get to a higher voltage for awhile.

Cheers.

TomW

[ghurd]

Even some of the $40, 400W inverters go off at 10.5V, back on at 11.9V.

Like a built in dump load.

Things are getting interesting!

[Nando]

Why a wind Mill used as a heat source needs MPPT.

Let's say that you have a 5 KW, Chinese wind mill that is used for heating purposes.

Since the generator is rated to a minimum of 5 KW, it may generate 2 or 3 more additional KWs.

The Wind mill starts to rotate and at that moment it has about 200 watts of energy, if one connects the 5 KW load the wind mill will brake immediately to a stand still.

So one needs to read the voltage and start inserting a low watts load or its equivalent, let's say that we have 1000 KW load, which by definition it is to heavy load for the 200 watts energy source.

The solution is to start to insert the load for a fraction of a second and read the voltage to determine the direction of the voltage changes, if voltage continues going up, the controller starts to increase the fraction of a second to present a greater load and the reverse if the voltage goes down with the inserted load for such fraction of time.

This reading and loading is done continuously and if the power increases, the load is inserted for a longer period of time until the generated power starts to be higher than the load so the variable time load is 100 % of the time ON.

The controller, at this moment, needs to insert another load , to maintain stability of the wind mill, and in this case the most practical way is to insert another 1000 watts load and resetting the first load to 0 time insertion.

So the first load is a PWM load that varies from 0 % time insertion to 100 % time insertion, and this variation goes up and down until an end ( 0 or 100 % ) is reached for the controller to add or remove a fixed load from the generator.

The second load is an equal fixed value load to the PWM load, and the subsequent loads can be equal or go in a binary step if the controller can do such variations.

So for this 5 KW ( 7 or 8 KW top power) the controller will have a number of loads that are inserted or removed as needed to maintain maximum power harvesting, and at the same time maintaining the stability of the Wind Mill

What happens if the wind keeps going up?.

If the power continues going up and the Furling has not started to rotate, then the controller in principle needs to have an ELC ( Electronic Level Controller) that has a set maximum generator output voltage allowed that if it is reached the controller starts to insert the loads at a pace fast enough that the generator is clamped to that maximum allowed voltage, let's say 240 volt AC.

The power, at the maximum voltage setting, may increase but the MPPT controller is not active because the ELC has taken over, it will become active once the generator voltage drops below the 240 volts limits and of course the RPM starts to slow down as well.

Regards

Nando

[richhagen]

Why not get a couple old automotive relays of suitable enough amps, and drive them through a voltage divider circuit, perhaps with a third resistor pulled from the relay back to provide some hysterisis, such that when the voltage is high enough they click on and when the voltage from the wind turbine falls they drop out.  You could add a couple large capacitors (old TV's and Monitors contain a wealth of parts) across the rectified DC from the wind turbine to add a bit more hysterisis to the system.  

In general, it is more work to heat with wood than to build a generator and a system to control it.  That is probably why most of the installations I have seen in remote areas use wood for heat and supplement it with passive solar and dump loads from their battery charging sources.  Keep us posted on what you build, this stuff is fascinating.  Rich Hagen

[electrondady1]

thanks for the explanation nando , a google search led me to a lot of posts were everyone knew how a mppt worked  

is this an exotic devise?

i will soon need a charge controller ,will it be difficult to find one that has a mppt ciruit included. if i inquire at the appropriate store will anyone know what the heck i'm talking about?

[nothing to lose]

Hmm, interesting. I had't thought of the braking power of the load I geuss was just thinking on the eat up available power. I guess conecting my 1500watt heating direct is not so  good. However I had thought about the battery/inverter/heater methode before also but some how it slipped my mind, now I think I know why I was thinking about it.

[TomW]

ntl;

Here is a wild idea I toyed with for direct driving heating elements.

Use motor run caps in series with and on either side of the load. One on each lead in other words. This should remove the "dead short" condition until it sees A.C. from the mill. It is actually pulses of D.C. until it gets going some so it may decouple the load to let it get spinning.

I never tried this but I "think" it might work. Whether or not it could pass the power I don't know.

Comments welcomed from those with a clue if it would work and if so suggestions on values.

Cheers.

TomW

[Gary D]

Hi Tom, Jerry had something on the frarads  (sp) he used to charge his electric truck off grid power. Tried to find the article under his user info. but no luck. Perhaps someone could find it. That was single phase tho, not sure if it would need to be modified for 3 phase?  

 If I understand your thoughts of caps on each end of the resistance heater load, the back set of caps would act as a battery kind of, to keep the first ones from dumping directly to ground (ie. holding voltage up)? Neat thought! Hope someone with a clue will jump in, clueless here.  Gary D

[TomW]

Gary;

Well my theory is based on the fact that capacitors block direct current and pass alternating current.

In my idea the capacitors would block those initial low speed pulses that are essentially rising D.C. pulses until we get some speed up and start seeing some A.C. and once the mill is turning the capacitors would happily pass the A.C. on to the element. Thereby removing the short circuit the mill sees when stopped. I thought using one per lead would enhance this effect over using one per phase or set of wires.

Cheers.

TomW

[Gary D]

Thanks for the response Tom. I found a circuit that Dave B is/was using that I think you are trying to simplify... The pic's just show up as a blank box with an x in for me tho... His again is for a single phase circuit tho, I'll try to post a link to the story.

 Gary D.

http://www.fieldlines.com/story/2005/1/3/222114/8823

[Bruce S]

G-

   Thanks for the fix. That's what I get for using Microsoft word to make sure my spel'n is corect.

Seem to have lost more than half my post on that one.

bummer

Bruce S

[Bruce S]

NTL;

   This is very similar to my solar charged, 12 17Ah battery connected to 200VA UPS with fish tank heater plugged into it for the plastic still.

OOOOHHH how all things are connected !!

Bruce S

[Dave B]

Gary and everyone,

  Dave B. here and a note on my variable load controller that I am currently experimenting with on my 12' single phase mill. It is based on the 3914 LED display driver IC. I tap off the AC of the alternator output and rectify this to give me the variable DC for the LED driver. A seperate AC/ DC "wall wart" provides constant DC voltage for the LEDs. A pot adjusts the referrence voltage for full scale of the 15 LEDS. I am trigerring 2 solid state relays at independent and adjustable voltage levels directly off the DC voltage of selected "Lit" LEDS. The triggered relays then switch the AC output of the alternator on / off to the heating elements. It has been working great for about a year now and I am constantly experimenting with load values and "cut in, speed" voltages to dial in the power avaialble from my 12' rotor. I plan to add a safety relay to automatically load the alternator and prevent overspeed (it does have  furling also) in the event of a power failure since the LED voltage and thus relay trigerring is provided by the AC/DC wall wort. Dave B.

[nothing to lose]

Yes,

"OOOOHHH how all things are connected !!"

 Soon I will be connecting many many things

Went to Harbor Frieght Friday. Got the $50 Noncontact Thermomoter on sale, regular $80.

Also couple packs of Nicd batteries and a charger, all about half price I think. Now maybe I can get pictures of stuff again since I have my own batteries for the kids camera, and maybe I can tell what the temps are for my still also. Tired of reading a thermometer showing me 130F while water drips out the tubbing and it burns my hand holding it, other one reads 170F right at the tank??? Something not right!

 The $50 Noncontact Thermomoter seems to be acurate too. Shoot a large thermomoter on the wall with the noncontact and they read the same or only 1F off.

 Going to try a wind gennie for the electric still heater soon also several ways and the baseboard heaters I may use in an old trailer house I use for storage. Cleaning up a room or two to use as a shop. Tired of this mess of never being able to get work done for various reasons. Giving up the rock house, seting up the old trailer on the inverter and batteries. Blacking out the windows so no light gets out, electric heat.

 No-one will even know I am in there working at night, so I should get things done. Was going to use wood heat, but smoke is a give away I am in there, though I thought about using charcoal for lots of heat but no smoke. Make charcoal with an outdoor wood furnace for the main house, use the gas for the cook stove, charcoal in wood burner at work trailer.

 Thinking of doing some camping in the van this winter also, use small electric heater and the site has decent winds for a small portable wind gennie normally.

OOOOHHH how all things are connected !

[Bruce S]

NTL;

   Good to hear about the thermometer .

Hope you didn't pour out that last batch that went too hot.

A good few hours in the freeze will take the extra water out.

Had my father-in-law take a look at the setup , he's the one with a PHD not me, and he was very impressed with the idea of freezing the water out of the Alky. He took a couple containers with him to test at the college. he's wanting to so several proof tests.

The hydrometer he brought with him read 160P coming straight out of the first run and 195P out of the freezer with it getting lower as the Alky warmed up and sucked in water from the air.

After 30 minutes at room temp and open to the air it settled at 190P.

He is now a little more than interested in seeing the full steps, especially since I did one of your tests which is to pour it directly into the air intake and listen to the engine purr.

So, if you haven't poured the other stuff out, put it in the freezer!!

He did correct one mistake that I made. Seems Mercury will freeze before ALKY.

Mercury freezes at -40F and Alky freezes at -140F but water still freezes at 32F so I'm safe enough to say that by using the freezer method is still a very viable way of removing water from Alky.

I wonder what kind of proof I can get if I lower the freezer to below zero, and whether it's worth the extra energy to get anything higher that 195 since I am now using the 160P straight.

Cheers

Bruce S

[nothing to lose]

We need a new diary, We got to almost 90 posts last time. Also we keep bumping into each other in various posts and get kinda off topic and back into the alky ourselfs.

 I think I'll start one up in a few days unless you want to start it, pics of my barrels, water tank still etc....

What problems I've had, and what works well for me also. We can link our other posts and diary in it.

I did not toss out the water batch, but I think it had too much water and might as well distill it over with more. Last try I got some good stuff till the the water started.

 I put about 1/4" gasolene in a clear glass jar and watched as the water sank to the bottom as the tube dripped into it. Too hot is my problem it seems.

Been raining and cold since I got the non-contact thermometer and not done another batch yet.

Also I been playing with a small DC motor for a wind gennie, and the baseboard heaters too. The heaters were all dirty, sitting years in the old trailer I use for storage now. Got one cleaned up pretty nice and ready to use. Might wire it up to the grid for this weekend and make sure it still works, then I have a 180v DC motor that should power the heater fine. I think I had figured it as about 2500watt motor when I got it. 180V at 15amps, around 2700watts?? Blades and a tower for it and I should have something there.

 We had enough wind the last 2 nights I could have had all the power I could have used if only I had a mill up then, made me sick!