Solar Generators

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kcol's picture
kcol
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Solar Generators

Does anyone have any info on solar generators?  I've read other threads on installing solar and I don't have tens of thousands to put into this.  I'm looking at basic backup.  I've looked at Solar Stik and Sunrnr.  I'm looking to spend $7000 or less. 

 

thanks

radardeb's picture
radardeb
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Re: Solar Generators

I just purchased one of these systems and am very pleased with it.  They have a smaller unit, also. 

 

http://www.mysolarbackup.com/playvideo.html

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Doug
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Re: Solar Generators

I've been trying to find a good source of diy instructions on building my own system for the entire house.  I've seen a couple ads for about $40-$50 that promise to provide instructions, but don't trust them without some kind of verification of their usefulness.  If anyone knows of a good source of such instructions, I'd appreciate hearing about it.

Doug

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earthwise
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Re: Solar Generators
Doug wrote:

I've been trying to find a good source of diy instructions on building my own system for the entire house.  I've seen a couple ads for about $40-$50 that promise to provide instructions, but don't trust them without some kind of verification of their usefulness.  If anyone knows of a good source of such instructions, I'd appreciate hearing about it.

Doug

I tried one of those, (hey, for $50 I figured it was worth a try) the info was decent, but the fly in the ointment is that even if you do it yourself, you still gotta come up with the solar cells to build it. The author says to look for them on E-bay , Craigs list etc., or find used cells from various sources but this didn't seem feasible to me. If you happen to have or find a source of cheap solar cells then this would be the way to go. If not, then save your fifty bucks IMO. 

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JAG
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Re: Solar Generators

Radardeb,

Thanks for the link to the portable PV system, its perfect for what I need. I also love the fact that I could hook up a micro-turbine wind generator to it as well.

Nate's picture
Nate
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Re: Solar Generators

I've been giving this a lot of thought due to our personal dependance on electric (mainly for water and the freezer).  My view is from a more scientific approach.  Si PV cells are only about 15% effecient.  This level is probably near it's peak due to basic physics (>50% light lost off the top due to the 1150nm Si absorption).  It is more efficient to convert light to heat and use the heat to make electricity.  My selection would be to concentrate light (parabolic mirror of Fresnel lens) and run a Stirling engine / generator.  About 35% efficient with early models, implying a much smaller footprint/KW produced.  The models I have seen on-line are too large for home use, but I haven't spent too much time searching.

 

Good luck.

 

Nate

kcol's picture
kcol
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Re: Solar Generators

What do you think about using a stand by generator like the Generac Guardian 17-20KW.  They run on either propane or natural gas and would power a house including AC.   I like the solar generators but they won't power as many things.

thanks

EndGamePlayer's picture
EndGamePlayer
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Re: Solar Generators

Yeah, Kcol- not much power there.

Since you don't want to spend much, try getting rid of the things you want to power (refrig/freezer, AC, wash machine, clothes dryer . . .) see:

MyBackAchers.com and Lehmans.com for more ideas on how to power-down your life.  Feel free to get creative! Then you'll have power for comminications and lights. . important "use every day kinda stuff".

Peace- EGP

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DrKrbyLuv
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Re: Solar Generators

Energy storage seems to keep coming up as a problem with various generators and collectors.  Here are a couple storage units that may be worth considering:

ZBB Energy Corporation with its Zinc Energy Storage System (ZESS)

RedFlow Technologies with its Zinc Bromine Module (ZBM)

 

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rhare
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Re: Solar Generators

Have any idea what these things are going to run (price)?  The smaller 10kWh unit would need to be around $20K USD to be cost competitive with a battery solution (2 SMA inverters, [email protected] AGM CRLA 20yr batteries).

-- Rob

 

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gyrogearloose
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Re: Solar Generators

In the early stages of setting up, but looking at Nickel-Iron batteries.

So far in looking the pros and cons are roughly

Very simple, can't kill with overcharging or draining dead flat Looonnnng life ( claimed examples of 40+ year old ones still producing reated capaicty) , easily refreshed by replacing the KOH ( with a trace of  LiOH ) solution after maybe10 years.

Big and heavy compared to lead acid ( well who cares in a fixed instillation... )

Cost

Oops  sorry thought I had bookmarked a site on them that even listed prices. Dam will have to find it again ( for my self ) but will add it here when I find it

 

Cheers Hamish

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Re: Solar Generators

The first thing you should ask yourself is, how much backup power do I need.  A full backup is nonsense and way too expensive. Unless you are in a very sunny region, I would not rely on just solar. Wind could be an alternative or addition. And even then a small diesel, petrol or propane fueled generator could be necessary. Size the battery pack to the number of days you are without sun or wind, taking the needed power consumption into account.

Nickel-iron batteries are the best, but expensive and it seems that the new produced cells from China are not all of them good. It is not that lead-acid batteries do not last very long. They can, but need maintanance and monitoring. Often they remain partially charged and are dead within a few years. A monthly full charge and equalisation, and flooded deep cycle lead acid batteries will last 20+ years. Note that I would take nickel iron batteries too, when offered at a reasonable price.

Either way, backup solar/wind systems end up complicated and expensive. Doesn't matter if you buy a plug and play system or build the whole system yourself. So when it is functional, start using it for part of your house. Keeps the system alive and it will teach you a lot.

Regards, DJ

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TNdancer
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Re: Solar Generators

Buying off the shelf components ( not the "build your own solar panels, buy my 49 buck book" baloney), you could

get about twice the panel and battery storage as these pre-packaged units.....and even at that,

it won't be a lot.  An analogy would be go to a restaurant and spend 100 bucks on a family meal, or buy the food

and feed the family 4-5 meals.

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Re: Solar Generators

Nate,

That doesn't even look good in theory.  Convert sunlight to heat to run a mechanical engine to turn a mechanical generator.

By the time you're done, I suspect your losses will be well below PV cells....not to mention having to build some type of tracking device to keep the concentrator well aligned with the sun so it will actually work.

But let me know if you actually get it out of the theory stage  :)

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TNdancer
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Re: Solar Generators

I posted this over in another forum, and thought some of you folks considering solar might be interested in some real life number versus theory. Keep in mind the SIZE of this system, and the relatively SMALL amount of power it produces, then pull out your own electric bill and do some comparison as to what this size system would do in your case ( and also factor in your location, your mileage may vary considerably )

My system is: 3150w panel rated. 18 x 175w Solarworld panels. 2 FM60 charge controllers, a 1200amp/hr AGM battery bank, 2 GTFX2524 inverters ( [email protected]). This system is grid tied in normal mode, and switched to off grid when the grid is down ( the GTFX inverter has an extra contact that closes when the grid contract opens on grid down, and diverts power to where ever you have it wired to go.....transfer switch in my case )
The panels are mounted on two sets of home built single axis trackers. These help the panels produce about 20-25% more power over the course of time than fixed mount, based on what I have measured by turning off the trackers and leaving them in the 'noon' position. The horizon angle of the trackers is fixed at 37 degrees, my latitude.

Here are the production numbers for 2010:

Solar Kw/hr......Total Kw/hr used....$$ paid to the power company

Jan---212...........1200...............................$55.07

Feb--149.............1854..............................121.04

Mar--168.............2092...............................141.92

Apr--203..............1813.............................118.72

May--295..............865.............................<0.26>

Jun--346...............679.............................<4.20>

Jul--296................847..............................22.20

Aug--366...............1132.............................34.05

Sep--291................985..............................37.59

Oct--407.................855...............................4.03

Nov--339................757...............................7.54

Dec--267.................664............................13.14

Total for year 2010: 3339 solar produced
Average per month: 278.25kw/hrs produced

Total used for 2010: 13,743
Average month: 1145kw/hrs

Total electric bills: $550.87
Average monthly bill: $45.91

NOTES:

1. This is my house, and my woodworking shop, and several farm buildings/etc. Some months I will run my dry kiln in the shop, and run the Kw/hrs up 200-300 for a month. It also depends on the amount of time I spend in the shop, several motors are 5hp on various machines, and the dust blower which runs with most machines is 3hp.

2. Also, we run stock tank heaters and chicken house heat in the winter, which tends to run the use up out of proportion to the year.

3. Being September, we switched to propane gas stove in the new kitchen, and changed the old fridge to a new model that uses about 1/2 the annual KwHrs of the old one, which will affect use some. Also switched to LED lighting in a major way.

4. We will run electric AC some in the summer, mostly July/August.

5. We get paid 12 cents OVER retail for all solar production ( TVA 10 yr contract ) Retail varies around 9 cents/kw/hr, depending on quarterly fuel adjustment. Amounts in <> reflect credit amount in our favor.

System cost about 20k, self installed.

Future expansion will be to add another 2450w of panels and one more charge controller ( FM80 ) to the system. That will max out what the two inverters will feed back to the grid ( they loaf along now at about 2.3-2.4kw best case ), and that will maximize all the equipment I have.  This expansion will run about $8,000....7k for the panels/extra charge controller, and 1k for another pole/tracker I'm currently in the process of building.  This one will be a dual axis tracker.

__________________
sevenmmm's picture
sevenmmm
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Posts: 108
Re: Solar Generators
TNdancer wrote:

I posted this over in another forum, and thought some of you folks considering solar might be interested in some real life number versus theory. Keep in mind the SIZE of this system, and the relatively SMALL amount of power it produces, then pull out your own electric bill and do some comparison as to what this size system would do in your case ( and also factor in your location, your mileage may vary considerably )

My system is: 3150w panel rated. 18 x 175w Solarworld panels. 2 FM60 charge controllers, a 1200amp/hr AGM battery bank, 2 GTFX2524 inverters ( [email protected]). This system is grid tied in normal mode, and switched to off grid when the grid is down ( the GTFX inverter has an extra contact that closes when the grid contract opens on grid down, and diverts power to where ever you have it wired to go.....transfer switch in my case )
The panels are mounted on two sets of home built single axis trackers. These help the panels produce about 20-25% more power over the course of time than fixed mount, based on what I have measured by turning off the trackers and leaving them in the 'noon' position. The horizon angle of the trackers is fixed at 37 degrees, my latitude.

Here are the production numbers for 2010:

Solar Kw/hr......Total Kw/hr used....$$ paid to the power company

Jan---212...........1200...............................$55.07

Feb--149.............1854..............................121.04

Mar--168.............2092...............................141.92

Apr--203..............1813.............................118.72

May--295..............865.............................<0.26>

Jun--346...............679.............................<4.20>

Jul--296................847..............................22.20

Aug--366...............1132.............................34.05

Sep--291................985..............................37.59

Oct--407.................855...............................4.03

Nov--339................757...............................7.54

Dec--267.................664............................13.14

Total for year 2010: 3339 solar produced
Average per month: 278.25kw/hrs produced

Total used for 2010: 13,743
Average month: 1145kw/hrs

Total electric bills: $550.87
Average monthly bill: $45.91

NOTES:

1. This is my house, and my woodworking shop, and several farm buildings/etc. Some months I will run my dry kiln in the shop, and run the Kw/hrs up 200-300 for a month. It also depends on the amount of time I spend in the shop, several motors are 5hp on various machines, and the dust blower which runs with most machines is 3hp.

2. Also, we run stock tank heaters and chicken house heat in the winter, which tends to run the use up out of proportion to the year.

3. Being September, we switched to propane gas stove in the new kitchen, and changed the old fridge to a new model that uses about 1/2 the annual KwHrs of the old one, which will affect use some. Also switched to LED lighting in a major way.

4. We will run electric AC some in the summer, mostly July/August.

5. We get paid 12 cents OVER retail for all solar production ( TVA 10 yr contract ) Retail varies around 9 cents/kw/hr, depending on quarterly fuel adjustment. Amounts in <> reflect credit amount in our favor.

System cost about 20k, self installed.

Future expansion will be to add another 2450w of panels and one more charge controller ( FM80 ) to the system. That will max out what the two inverters will feed back to the grid ( they loaf along now at about 2.3-2.4kw best case ), and that will maximize all the equipment I have.  This expansion will run about $8,000....7k for the panels/extra charge controller, and 1k for another pole/tracker I'm currently in the process of building.  This one will be a dual axis tracker.

__________________

I have been preparing for my final application of renewable energy - exactly what you have installed.

Since i am up in Wisconsin, the first measure taken was to insulate and seal the house. We had a contractor come and pump aircrete into the walls, and we installed sheep wool - treated with boric acid - to R55 in the attic. We received $1500 in state incentives to help defer the cost. The next item was a 3 collector solar air heater - this puppy heats my house to over 80 degrees, from 60ish, on a sunny, zero degree day (it is easy to notice the coldest days are the sunny ones!). The next item was a solar domestic water heater. The incentives from the state and federal government brought the bill for this device to below half of the cost. In terms of ROI, this was the order of best to least.

I have just begun researching to buy a solar electric system. Have received one bid thus far of $30,000 for a 3700w system. Have recently purchased one of those refrigerators (don't believe the claim it is quiet though), a new freezer, a new LED TV, and all of the bulbs are now LED as well. So I am ready. I have wanted to be totally sustainable since I bought the house in 1984 (my wifey would argue that), and I am almost there.

Good information, thanks a lot. 

Oh, by the way, one of those generators may have enough power to keep the computer on long enough to learn what to do in an emergency! Haha!

TNdancer's picture
TNdancer
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Re: Solar Generators
sevenmmm wrote:

 

Oh, by the way, one of those generators may have enough power to keep the computer on long enough to learn what to do in an emergency! Haha!

 

Yeah...if it's a small laptop.....ahahaaaa....

 

We did the house insulating thing from the get-go back in 1985 when we built it.  10" thick walls ( double 2x4 + air space+ foam board ) outside, 12" overhead fiberglass, and so on.  Always heated with wood....so our use has been fairly low all along, I estimate about 700kw/hrs/month for the house alone ( shop+other buildings on the same meter )  Last step was tightening up on  lighting and appliances.  We have 3 freezers ( all older ) and a 6'x6' walk-in cooler I built to hang farm grown pork/beef when we slaughter...but that only runs few weeks a year.

That 30k for the 3700w, is that a grid tie only system ?   Around here, I understand the going price is about $7/watt for a grid tie only system ( no battery backup ), so that's not too out of line with what I see here.  You could self install that for about 17-18k, if you're inclined to do so.

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sevenmmm
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Posts: 108
Re: Solar Generators

 

Yeah, that was grid tie and micro inverters. I could do the installation all the way up to the grid tie, I'll have to think about that. We also have another older  freezer  and fridge we do use periodically, and the wifey said the kilowatt meter pegged out when she tested them. I am thinking to replace it with the current (noisy) fridge/freezer and try another brand. My goal is below annual 200 KW h. Our lowest monthly electrical use was 624 KW h, be nice to get it down that low (or lower) the whole year.. 

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BuzzTatom
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Re: Solar Generators

What is your opinion of the Solar Air Heater? What does your ROI look like on it right now? Have house in MT that I am fixing to go down the same steps you went through. Insulation will be first for sure although it is pretty good already but very curious on your thoughts on your air heater.

 

 

Thanks, Buzz

 

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sevenmmm
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Re: Solar Generators

 

Have a very high opinion of them, but the ROI is hard to pin down. Cost of the install, cost of your heating fuel, and the number of sunny days per winter need to be determined. One thing is for certain, the cost of fuel over the 50 year lifespan will continue upwards & the ROI is guaranteed to increase with it, AND, solar heaters will keep you warm in the process. Of course, in comparison, when you lose money in the stock market, one can get quite warm as well.

Here is some work on solar heating a business I am associated with has done (they won't work in MT):

 

http://www.greenskyenergetics.com/Residential/SolarAirHeating/tabid/65/Default.aspx

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lacourre
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Nate wrote: I've been giving
Nate wrote:

I've been giving this a lot of thought due to our personal dependance on electric (mainly for water and the freezer).  My view is from a more scientific approach.  Si PV cells are only about 15% effecient.  This level is probably near it's peak due to basic physics (>50% light lost off the top due to the 1150nm Si absorption).  It is more efficient to convert light to heat and use the heat to make electricity.  My selection would be to concentrate light (parabolic mirror of Fresnel lens) and run a Stirling engine / generator.  About 35% efficient with early models, implying a much smaller footprint/KW produced.  The models I have seen on-line are too large for home use, but I haven't spent too much time searching.

 

Good luck.

 

Nate

 

Nate,  I am really intrigued by the Fresnel/Stirling combination.  Have you checked out Green Power Science... they may have the size that you are looking for?

http://www.greenpowerscience.com/SHOPSTIRLINGENGINES.html

 

Nate's picture
Nate
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Posts: 605
lacourre wrote: Nate
lacourre wrote:
Nate wrote:

I've been giving this a lot of thought due to our personal dependance on electric (mainly for water and the freezer).  My view is from a more scientific approach.  Si PV cells are only about 15% effecient.  This level is probably near it's peak due to basic physics (>50% light lost off the top due to the 1150nm Si absorption).  It is more efficient to convert light to heat and use the heat to make electricity.  My selection would be to concentrate light (parabolic mirror of Fresnel lens) and run a Stirling engine / generator.  About 35% efficient with early models, implying a much smaller footprint/KW produced.  The models I have seen on-line are too large for home use, but I haven't spent too much time searching. 

Good luck. 

Nate

 

Nate,  I am really intrigued by the Fresnel/Stirling combination.  Have you checked out Green Power Science... they may have the size that you are looking for?

http://www.greenpowerscience.com/SHOPSTIRLINGENGINES.html 

Sorry,

I didn't follow up and found this thread again.

  http://www.infiniacorp.com/

Need to do more research!

Nate

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