Solar recommendations?

[NomadS]

Anyone have any experience with solar power for off grid locations?

Interesting in knowing what functional system would cost and what exactly would be needed.

I don't expect it to run everything in a typical house. Only want to run a Fridge/Freezer, a few LED light, maybe a fan or two, and be able to charge some power tool batteries.

I think the biggest concern is the battery system. With our, less than ideal for solar, sunlight conditions they would have to hold enough to make up for the days when we don't see the sun.

 

[remauto1187]

Anyone have any experience with solar power for off grid locations?

Interesting in knowing what functional system would cost and what exactly would be needed.

I don't expect it to run everything in a typical house. Only want to run a Fridge/Freezer, a few LED light, maybe a fan or two, and be able to charge some power tool batteries.

I think the biggest concern is the battery system. With our, less than ideal for solar, sunlight conditions they would have to hold enough to make up for the days when we don't see the sun.

NOTHING ABOUT THIS SYSTEM IS GOING TO BE CHEAP WHEN WANTING TO POWER A SUBSTANTIAL AMOUNT OF LOADS!
Anything with electric motors is whats gonna consume the most power, especially when the motor first kicks on. You will have to decide whether you are going with strictly a 120vac system or 240vac.
If you go with a 240vac then you can add in a simple manual/auto transfer switch parallelled off your breaker panel. If you go with a 120vac system then you will need a more elaborate/costly setup. There are many ways to setup but some are unsafe, illegal, suicidal and then some are just a big pain.
You will need deep cycle batteries, inverter, solar panels, wiring(larger the better), charger/controller, DC Disconnect, AC disconnect and manual/auto transfer switch. (YOU MUST BE ABLE TO DISCONNECT YOUR HOME FROM THE POWER COMPANY WHILE OPERATING YOUR SOLAR POWER SYSTEM!)...Easily done by shutting off your main breaker OR install a Meter/Breaker Base.
You can make your own solar panels by buying the materials and solar cells off ebay or other suppliers. I am at less than .50 cents a watt. Typical already built solar panels run around $3 a watt! A standard deep cycle battery runs around $85 ea. You will need atleast 4 (more the better) in parallell (12vdc inverter system). The actual amount will be determined by your loads (Wattages added up) and then of course how much sun you will have to offer your system. It is not good for your system to take the batteries below 50% charge often. The overall battery life will suffer dramatically.
This is a basic breakdown. There are more specifics once you start building your system. Sizing your wiring is very important with DC since voltage drops will kill your efficiency.
A modified sine wave inverter will run just about anything in your home except your tv and some circuit board equipped furnaces may not like the modified wave. A true sine wave inverter will be needed for your tv and possibly furnace. Modified sine wave inverters are fairly cheap. I picked up a 2000w continuous 4000w peak for $150. True sine wave inverters are fairly expensive.
You are looking at easily a couple grand for your system and even more if you want to be able to run all those motors. There is where the battery costs and inverter costs get you. Dont forget electrician bill if you cant do it all yourself. If you dont know how to safely work with electrical or how to follow the NEC then you will just be asking to burn your place down with a project like this.

 

[Sailor]

You may be better off using solar for led lighting and just using one of those table top icemakers. They make 28lbs of ice a day, with a well insulated cooler you are gtg. They are WAY more efficient than making ice in a freezer by air contact. Run it off your car, with an invertor or battery that you are recharging.

 

[rat-man]

I'm very interested in this too, but it's a pipe dream at this point.

I do remember this story about a kid who figured out how to get max efficiency out of solar panels by arranging them the way tree leaves are in nature.

13-Year-Old Designs Super-Efficient Solar Array Based on the Fibonacci Sequence | Popular Science

 

[CathyInBlue]

Most modern conveniences that use AC really use DC, they just transform and rectify the AC current internally to get the DC voltage(s) they want. It would be more efficient to reverse engineer the power supply in your TV, Computer, Microwave, climate control, etc. and then install appropriate DC-DC converters. Provided you don't have a large house where you have to send DC current dozens and dozens of feet, a central DC battery bank kept topped off by a solar charger can run everything in a modern house.

The only real sticking point is motors. There's no way to run your HVAC's circulation fan motor or your fridge's compressor motor off DC. The most straight forward solution I see is to buy DC appliances in the first place. The second most straight forward solution is to replace those motors with brushless DC motors. Problem is, a proper, efficient brushless DC motor controller can out strip the cost of the motors themselves, which are themselves more expensive than the AC induction motors you'd be replacing.

Just remember, every time you convert energy from one form to another, there's a conversion loss. Solar light --> DC current --> maximum power point tracked DC --> chemical storage battery --> DC current --> AC inverter --> TV power supply DC current. Every step is loss, loss, loss. Best thing to do is to use energy as directly as possible. The sun is about light and heat. Maximize home direct solar lighting; minimize home electric and combustion lighting. Use solar thermal heat collectors where heating is needed; use solar photo-voltaic collectors where electricity is needed.

That tree leaf solar cell thing was a fraud. http://www.smartplanet.com/blog/thi...s-solar-power-8216breakthrough-wont-work/8261

 

[downzero]

I'm very interested in this as well. I could wire the whole thing myself, and everyone selling "systems" online seems like a scammer. Using 12v deep cycles for some storage is something I hadn't considered before. I would especially like to see discussion of cheap solar panels themselves, since the rest is just controls/details.

 

[downzero]

Also, does anyone know of a way to have an integrated system? Having solar as a backup to the grid is fine in an emergency, but for it to be really effective, I think you'd really need to get your meter to spin backwards most of the time and only use the grid when the AC or other high-draw devices are running.

 

[CathyInBlue]

It's those controls/details that will make or break your solar system's efficiency and usefulness for any given purpose.

Sounds like what you want is a professionally integrated grid inter-tie system.

 

[downzero]

It's those controls/details that will make or break your solar system's efficiency and usefulness for any given purpose.

Sounds like what you want is a professionally integrated grid inter-tie system.

There's nothing saying you couldn't have both paralleled together, though (backup power and integrated system).

And yes, I would want a integrated system, but the controller itself has to be available. There are tons of places online that sell "kits," but I have a suspicion, yet unverified, that these "kits" are more expensive than building one's own. I have no problem installing/wiring a system, but I would need to know what's out there in terms of controls to actually integrate the two systems.

I do agree with you that transferring energy from one type to another has loss problems, but for all intents and purposes, the sun is a limitless source of energy. The difficulty is finding a cost-effective method of capturing it and putting it to productive use in a way that overcomes the losses. And on that point, I'm open to suggestions.

From a pure theory point of view, your idea of a DC system for one's house is brilliant, but it relies on the assumption that minimizing losses and maximizing the use of the output of each solar panel is the most efficient solution. Considering the life of the panels, I suspect that installing more solar panels and integrating the system would more cost-effective, because it would allow you to power any or nearly any device, even if it did require a larger initial outlay for more solar panels.

I'm not saying that you're wrong, because I don't know, honestly, but I do think that it would be easier, and possibly more cost effective, even if it involved more losses from conversions, to integrate the solar system into the existing 220 volt AC service rather than to go back to Westinghouse vs. Edison.

 

[remauto1187]

Also, does anyone know of a way to have an integrated system? Having solar as a backup to the grid is fine in an emergency, but for it to be really effective, I think you'd really need to get your meter to spin backwards most of the time and only use the grid when the AC or other high-draw devices are running.

Thats exactly what a grid tie inverter does.... IT WILL NOT put out power unless it "sees" commercial power first. The grid tie inverter matches its output in frequency and voltage to the commercial power so that both can be applied to your home electrical system. If you use less power than your solar system makes and have extra then your meter turns backwards. If you use more than what your system can provide then you use the balance from the power company (meter goes forward). The drawback is that when the power company fails to deliver power to your home, your solar system is useless. You will then need a generator. The reason being is that the safety feature builtin the grid tie inverter allows you to attach its output directly to your breaker panel without any fancy transfer switches but it MUST "SEE" commercial power there to even turn on and match its output. This keeps your system from energizing the power lines while linemen are out there (or even down the road) working on the power lines that are suppose to be dead (thats why they got called out to repair...remember there was a power outage).

 

[downzero]

Thats exactly what a grid tie inverter does.... IT WILL NOT put out power unless it "sees" commercial power first. The grid tie inverter matches its output in frequency and voltage to the commercial power so that both can be applied to your home electrical system. If you use less power than your solar system makes and have extra then your meter turns backwards. If you use more than what your system can provide then you use the balance from the power company (meter goes forward). The drawback is that when the power company fails to deliver power to your home, your solar system is useless. You will then need a generator. The reason being is that the safety feature builtin the grid tie inverter allows you to attach its output directly to your breaker panel without any fancy transfer switches but it MUST "SEE" commercial power there to even turn on and match its output. This keeps your system from energizing the power lines while linemen are out there (or even down the road) working on the power lines that are suppose to be dead (thats why they got called out to repair...remember there was a power outage).

That makes sense. I disagree with you that the system would be useless though. What would be necessary is a way to manually disconnect the output of your solar bank from that inverter and connect the same to your battery bank and its inverter for emergency purposes. As long as the sun is shining, those panels are making power.

And yes, I see what you're saying about energizing the lines, but you can kill your main breaker and stay on backup power until the grid comes back up.

I don't mean to hijack your thread, but you can have both systems, they just can't run concurrently, at least not into the panel at the same time. But the only thing you'd need is a pair of knife switches and you could make it work, just make sure you shut off the integrated system before switching to the backup, and all components are rated for the current that your panels can supply.

 

[remauto1187]

There's nothing saying you couldn't have both paralleled together, though (backup power and integrated system).

And yes, I would want a integrated system, but the controller itself has to be available. There are tons of places online that sell "kits," but I have a suspicion, yet unverified, that these "kits" are more expensive than building one's own. I have no problem installing/wiring a system, but I would need to know what's out there in terms of controls to actually integrate the two systems.

I do agree with you that transferring energy from one type to another has loss problems, but for all intents and purposes, the sun is a limitless source of energy. The difficulty is finding a cost-effective method of capturing it and putting it to productive use in a way that overcomes the losses. And on that point, I'm open to suggestions.

From a pure theory point of view, your idea of a DC system for one's house is brilliant, but it relies on the assumption that minimizing losses and maximizing the use of the output of each solar panel is the most efficient solution. Considering the life of the panels, I suspect that installing more solar panels and integrating the system would more cost-effective, because it would allow you to power any or nearly any device, even if it did require a larger initial outlay for more solar panels.

I'm not saying that you're wrong, because I don't know, honestly, but I do think that it would be easier, and possibly more cost effective, even if it involved more losses from conversions, to integrate the solar system into the existing 220 volt AC service rather than to go back to Westinghouse vs. Edison.

It boils down to, that most will not have the know how to convert their stuff to strictly DC. Then of course not all will run on 12vdc or even 24 or 48vdc. The losses can be minimized in your DC delivery wiring from your solar panels...GO BIG....REAL BIG! Then of course your battery connecting wires and your wiring from the output of your inverter(s) to your home wiring/sub panel. LED LIGHTING is one of the first things you need to get swapped over to in your home. 120vac lighting really sucks power on a solar system. The CFL's are roughly a 1/4 of the power consumption but LED really is the way to go if you are going solar.
To really cut costs by atleast half if not alot more...BUILD your own solar panels. I have 550w worth of solar cells right now ready for me, now all i have to do is finish all my before winter home repairs. ROOFING..gotta love it!

 

[downzero]

That's really awesome if you can build your own solar cells. Next year, I am moving to a place that gets 350 days of sun per year. Needless to say, I need to get to doing some research on this.

Also, LED lighting will be much cheaper and more available in the near future, but I definitely agree with you, inexpensive reductions in current draw are a great way to make it more efficient.

reps all around

 

[remauto1187]

That makes sense. I disagree with you that the system would be useless though. What would be necessary is a way to manually disconnect the output of your solar bank from that inverter and connect the same to your battery bank and its inverter for emergency purposes. As long as the sun is shining, those panels are making power..

The system is useless setup the "normal" way. There is always a way to do things different without a doubt.

And yes, I see what you're saying about energizing the lines, but you can kill your main breaker and stay on backup power until the grid comes back up.

An electrical inspector will never approve this because it is illegal. The power company WILL NOT hook your power up with it like that. Its also illegal and the first time you forget to kill that breaker and end up killing a lineman you are done! His family will own everything you have and you most likely will end up in jail for involuntary/voluntary manslaughter!

I don't mean to hijack your thread, but you can have both systems, they just can't run concurrently, at least not into the panel at the same time. But the only thing you'd need is a pair of knife switches and you could make it work, just make sure you shut off the integrated system before switching to the backup, and all components are rated for the current that your panels can supply.

Of course there is a way...a fancy transfer switch or a correctly sized disconnect.

 

[remauto1187]

That's really awesome if you can build your own solar cells. Next year, I am moving to a place that gets 350 days of sun per year. Needless to say, I need to get to doing some research on this.

Also, LED lighting will be much cheaper and more available in the near future, but I definitely agree with you, inexpensive reductions in current draw are a great way to make it more efficient.

reps all around

YOUTUBE! There are a bazillion how to vids on making your own solar panels. Its actually really easy. Just word of caution, the solar cells themselves are very FRAGILE, VERY! Like a sheet of mica.

 

[downzero]

Of course there is a way...a fancy transfer switch or a correctly sized disconnect.

Uh, that's what I said the whole time. There are manual transfer switches. They are not illegal. If what you're saying is that you'd need a double throw disconnect, that is not expensive and can be done.

You have to open the circuit between your panel and the grid to energize your panel somehow. If what you're saying is that the main breaker is insufficient to meet code, I have not consulted it on that particular point and so I wouldn't have any reason to disagree with that. Regardless, you have to electrically open the circuit one way or another.

And yes, as you point out, there are automatic ways to do it as well, but they are very expensive. But perhaps not a bad if one considers the life of products like this.

 

[remauto1187]

Most modern conveniences that use AC really use DC, they just transform and rectify the AC current internally to get the DC voltage(s) they want. It would be more efficient to reverse engineer the power supply in your TV, Computer, Microwave, climate control, etc. and then install appropriate DC-DC converters. Provided you don't have a large house where you have to send DC current dozens and dozens of feet, a central DC battery bank kept topped off by a solar charger can run everything in a modern house.

The only real sticking point is motors. There's no way to run your HVAC's circulation fan motor or your fridge's compressor motor off DC. The most straight forward solution I see is to buy DC appliances in the first place. The second most straight forward solution is to replace those motors with brushless DC motors. Problem is, a proper, efficient brushless DC motor controller can out strip the cost of the motors themselves, which are themselves more expensive than the AC induction motors you'd be replacing.

Just remember, every time you convert energy from one form to another, there's a conversion loss. Solar light --> DC current --> maximum power point tracked DC --> chemical storage battery --> DC current --> AC inverter --> TV power supply DC current. Every step is loss, loss, loss. Best thing to do is to use energy as directly as possible. The sun is about light and heat. Maximize home direct solar lighting; minimize home electric and combustion lighting. Use solar thermal heat collectors where heating is needed; use solar photo-voltaic collectors where electricity is needed.

That tree leaf solar cell thing was a fraud. Why 13-year-old’s solar power ‘breakthrough’ won’t work | SmartPlanet

A woman with some engineering edumacation ..... Where were you BEFORE i met my X-wife?

 

[remauto1187]

Uh, that's what I said the whole time. There are manual transfer switches. They are not illegal. If what you're saying is that you'd need a double throw disconnect, that is not expensive and can be done.

You have to open the circuit between your panel and the grid to energize your panel somehow. If what you're saying is that the main breaker is insufficient to meet code, I have not consulted it on that particular point and so I wouldn't have any reason to disagree with that. Regardless, you have to electrically open the circuit one way or another.

And yes, as you point out, there are automatic ways to do it as well, but they are very expensive. But perhaps not a bad if one considers the life of products like this.

Yes, using the main as a disconnect is illegal...because you know there will be some idiot out there that forgets to do it. When i was in the Navy and used the aircraft publications on the F/A-18C Hornets, there was always a safety or danger statement....We were always told someone probably died or got really messed up to get those safety/danger notifications printed in there by Mcdonnel Douglas.
Im not sure where you are but Duke Energy is the power company around here and your local power company usually provides some guidance on solar panel system rules, etc. Checkout my local power company link for ins and outs, there is even calculators on there. Generate Your Own Power - Indiana Residential-Duke Energy

 

[NomadS]

PLEASE don't hijack the thread. Keep this to OFF GRID since it is in the survival section. And system for both on/off grid is a good topic for a different thread.

Want to find an inexpensive ( or rather least expensive) way to give power to an 100% off grid location. Powering some lights, fridge/Freezer to keep food items from spoiling.. not for ice production. (I plan to further insulate the fridge Freezer to minimize power consumption), and a few fans for some cooling. Will have wood heat.

So far sound like DC system (have not bought a fridge yet so that is still an option) is the way to go. Although I imagine that also means I will have to make sure lights and fans are DC powered.
DE-0061/EV-0061 is an option.. power use 12/24v=3.2-2.2 amp

Any ideas on cost? (panels, batteries, wiring, etc) not including appliances etc..

 

[shibumiseeker]

I have been off-grid for the last 2 decades. Do a search on my username and "solar" or "off-grid" and you can find a bunch of stuff I have written on this site about my system and giving other people advice about their systems.