"Solar/Wind Electric Backup" Virtual Build Party Feeler......

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TL;DR. Not possible for under $10k


Would anyone be interested on putting our heads together and designing and building a dual source solar and wind electrical backup system over the winter? We can share thoughts, research, progress pics and results over NES. Having the support of other NESers working on the same project would be a good motivator and remove some of my apprehension about undertaking this project.

My requirements for my systems are flexible, but go something like this...
- Ability to power several appliances for a few hours each day or my well pump when needed.
- I do not need "hot" fail over. Throwing some switches once per day during a blackout is fine.
- My assumption is that I can use wind when there is no sun (hence the dual source idea), but some sources believe this would be a waste of time/money
- I'm not a "make everything from scratch" purist.
- I would like to avoid "budget" components that will fail when needed most.
- I'm thinking the all in budget will be 1k-2k

Thoughts?
 
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I stumbled upon this awhile back. Decent overview for off-grid backup. I'd probably want more capacity. Right now I have a generator I used once.

The solar isn't a priority right now, but when you need it you probably wish you had it.
 
My senior project in college was a wind turbine. It utilized pitching blades that depending on wind speed could adjust for maximum torque on the little RC helicopter motor we were using.
Output wasn't enough to power anything substantial but if you look to charge a series of car batteries in parallel that could work over time. It's been a few years and the math is lost on me, so I wouldn't be much help beyond that.
 
if you plan for the long term, good batteries for this purpose (Li ion gel type) the cost for them will be out of you target. the good ones I've seen carry price tags over $1-2K each and you'd likely want 2-4 of them with 100 amp/hr capacity.
 
My senior project in college was a wind turbine. It utilized pitching blades that depending on wind speed could adjust for maximum torque on the little RC helicopter motor we were using.
Output wasn't enough to power anything substantial but if you look to charge a series of car batteries in parallel that could work over time. It's been a few years and the math is lost on me, so I wouldn't be much help beyond that.

Very interesting. The wind turbine option seemed like a good idea to me for the 5-10 weeks per year we go without any sun.

Any recollection of the charge rate increase of your pitching rig versus fixed blade?
 
Very interesting. The wind turbine option seemed like a good idea to me for the 5-10 weeks per year we go without any sun.

Any recollection of the charge rate increase of your pitching rig versus fixed blade?
No, but a general memory was that you would have needed very high wind speeds for our small (3-4") blades to even turn at the fixed pitch where we saw the highest output. We used an Arduino to control the servos and adjust pitching and had an emergency shut down mode where if the rpms got too high it would set them to maximum brake pitch and slow them down to much slower speeds.
 
Keep in mind we were limited on our output and budget for our competition, so while we were using RC motors you could in theory use a series of slightly larger ones as needed to match your voltage needed to charge the batteries you pick. Build a rectifier with capacitors on the output to smooth out the peaks and condition the power you're delivering. Spend money on appropriate components too, if you don't have the right power rated stuff you'll get smokey quick.
 
if you plan for the long term, good batteries for this purpose (Li ion gel type) the cost for them will be out of you target. the good ones I've seen carry price tags over $1-2K each and you'd likely want 2-4 of them with 100 amp/hr capacity.

Yes. Long term.

My calculus is that I can get a good generator setup, for 3-4K. But for anything longer than a week...I’m out of fuel (assuming no resupply). Hence my interest in this approach.

Are there no other options for batteries besides the Kardashian models (Expensive Gel Filled)?
 
SolarEdge inverter (StoreEdge) will give live backup without a battery but a system is out of your range
 
- I'm thinking the all in budget will be 1k-2k

An inverter and batteries alone will well bust this budget. Just a wild ass guess but you're probably looking at $8K to $10K in parts and materials alone to do what you want plus a big headache to make it all work.

Properly preparing for long term power outages pretty much guarantees you will never have one, it's some kind of cosmic rule.
 
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Would anyone be interested on putting our heads together and designing and building a dual source solar and wind electrical backup system over the winter? We can share thoughts, research, progress pics and results over NES. Having the support of other NESers working on the same project would be a good motivator and remove some of my apprehension about undertaking this project.

My requirements for my systems are flexible, but go something like this...
- Ability to power several appliances for a few hours each day or my well pump when needed.
- I do not need "hot" fail over. Throwing some switches once per day during a blackout is fine.
- My assumption is that I can use wind when there is no sun (hence the dual source idea), but some sources believe this would be a waste of time/money
- I'm not a "make everything from scratch" purist.
- I would like to avoid "budget" components that will fail when needed most.
- I'm thinking the all in budget will be 1k-2k.

Thoughts?

My thoughts are, Your all in budget is not well researched and falls many thousands short for your expectations.
 
You can pull off a system for $2k but it will be limited to running a couple of led lights and running a small fridge.

I have a 9600 watt rooftop system - it produced 2kW/Hrs yesterday. That's not even enough to keep the foodccold.

Panels are about $1/watt

Inverter/charge controller is going to be around $1k for something that won't rape your induction motors.

Then you need racks to mount the panels and batteries to store the power.

Four 100amp*Hr batteries will give you around 5kWHrs (short term) which is enough for rough living - But you will need 1kW of panels to fully charge on a good solar day or 2.5kW for an average day.
 
You can pull off a system for $2k but it will be limited to running a couple of led lights and running a small fridge.

About what I was thinking - $2K will let you charge your phone and flashlight batteries.

Inverter/charge controller is going to be around $1k for something that won't rape your induction motors.

He wants to run his well pump so he would need, what, at least a 3KW inverter?
 
Excellent info! Thanks everyone!

Reality seems to be: A “DIY Science Fair” version of this setup is useless in any real world situation.

Major components alone will cost:

5kw inverter: 1,000
Charge controller: 300
3kw Panels: 3,000
Batteries: 3,000
_______________________
Big Stuff: 7,300



So....

That was a great project! I can’t believe I finished it so quickly!! Everyone helping out made the time really go by fast

I will send everyone pics of my Kohler 14kw professionally installed generator with auto transfer switch when it’s in place.
 
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Updating the well pump to a VFD pump would lower the peak power needs but is a large investment.
 
I’d love to have a system just as the OP describes.
I don’t see any reason a wind turbine can not
be made to work with New England wind?
Technology is at a point we could do it no problem.
We just won’t. Oil companies don’t want it.
Along with local power companies.
As the OP correctly states, if we want this we’ll
have to do it ourselves!
I’m a layman when it comes to aerodynamic design
at best but I know it can be done on the cheap.
Fiberglass prop on a decently efficient dynamo?
I bet can be had off the shelf. Add to that lead acid batteries
and your all but there. I think the big ticket item will be the
panels. Would 15 do it? What’s 15–250w panels worth?
I bet this could be done close to 5K. I’m talking a cabin
in the woods system not a 100KW don’t notice anything
is wrong system. You engineers out there can do this
if you wanted. Prop and dynamo are the big items
that need to be sourced. All else can be found
off the shelf.
 
Excellent info! Thanks everyone!

Reality seems to be: A “DIY Science Fair” version of this setup is useless in any real world situation.

Major components alone will cost:

5kw inverter: 1,000
Charge controller: 300
3kw Panels: 3,000
Batteries: 3,000
_______________________
Big Stuff: 7,300



So....

That was a great project! I can’t believe I finished it so quickly!! Everyone helping out made the time really go by fast

I will send everyone pics of my Kohler 14kw professionally installed generator with auto transfer switch when it’s in place.

So what's the damage on the generator installed?

Why 14kw and what's the fuel consumption looking like.

Are these things loud as hell?
 
I often wondered about the solar companies that install panels on your roof at no cost to you. I would think that they could increase their sales if they offered the option of a battery bank on the system, even if the home owner had to pay for the battery bank.
The bank could be charged off of the home owners electric panel, and when the grid goes down it could be switched over to the solar panels.
The solar companies don't benefit from the solar panels when the grid is down, so I wouldn't think that the would be opposed to this.
 
I arranged a Koehler backup generator system for my cousin from a local company. It came in at just under 10k. It would have been a bit less if she had Natural Gas.
 
I often wondered about the solar companies that install panels on your roof at no cost to you. I would think that they could increase their sales if they offered the option of a battery bank on the system, even if the home owner had to pay for the battery bank.
The bank could be charged off of the home owners electric panel, and when the grid goes down it could be switched over to the solar panels.
The solar companies don't benefit from the solar panels when the grid is down, so I wouldn't think that the would be opposed to this.
The payback is in the SRECs - $250 per MegaWatt-Hour
My 9.6kW system produces around one SREC per month so I get paid to have it on my roof (I own my system)
 
The payback is in the SRECs - $250 per MegaWatt-Hour
My 9.6kW system produces around one SREC per month so I get paid to have it on my roof (I own my system)
That's great, how many years will it take to pay for it self?
 
That's great, how many years will it take to pay for it self?

Would like to hear this as well for a 10kW system.

Some years back I went thru an estimate exercise on a 5kW system. It came to an average savings of 25% of my bill annually.
Say I spend $4k/yr on electricity I'm saving approximately $1k/yr. Now didn't account for selling back what I didn't use on low use sunny days. Probably not much with a small 5k system and running 2 outdoor AC compressors with allergy/asthmatics a good part of the year.

At the time when I questioned the long payback with the system, the solar rep said people were doing it for the environment - go green, save the planet, feel good stuff. Sorry I'm a grain of sand and not going to help much against the global industrial machine, or even Al Gores energy footprint :D
 
The problem is panels cost a lot

A windmill you might be able to throw together from found parts
 
We installed a system last march, definitely not a budget system.

12.6 KW of LG 350 watt panels (25 year warranty)
9.84 KW of inverters (just below the 10KW AC net metering limit)
Expect to produce 15,000 KWH per year; .24 per KWH saved is $3,600/year, $3,000 per year in SRECs.
We own the system; after the 30% tax credit, the payback period 5.3 years.

This is the technology we used The Pika Energy Island™ - Smarter home energy storage - Pika Energy

We will be adding a battery soon, about $11K for an 11KWH battery, if it is sunny you can run more things during the day;
we produced 44 KWH today. It may also reduce some of our clipping (when the panels produce more than the inverter rating.)

Battery/ Pika inverter will power - well, freezers, fridges, furnace, AND our heat pump hot water heater (600 W).

After being without power for a week twice, by day 4 you just want a shower and the toilet to flush.
 
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