Ah....an outdoor boiler....that makes more sense that what most people mean when they talk about rocket mass heaters.
Adding solar to an old on grid homestead
- Thread starter Alaskajohn
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As with anything else, they have a purpose. The purpose may be ideal for some and of no value to others. For the small amount of wood they need to heat up the "mass" there are few options as efficient. My suggestion of running a water line through the "mass" would allow warm/hot water eliminating the use of the electric water heater the OP currently uses. If the OP was cut off from public electricity that water heat would be his biggest power consumption and would drain batteries on a solar system pretty quick. They have a purpose, it may not be what the OP needs but it is something to be considered. That being said they do burn very efficient and they do get real hot but instead of using 6" or 8" pipe a smaller one made of 3" or 4" pipe would still get pretty warm and still be very efficient but the level of heat would be reduced to a more moderate level. I designed and built my home prior to learning about rocket mass heaters or I would have designed a corner for a small bench to contain the RMH, but when I build my patio outside I am considering a small RMH bench to I can sit outside and be comfortable in the winter months.
Again, it may be good for some, but it isn't for everyone.
Fwiw (as, not sure if 'Shipping to AK' will negate any possible 'gains', via this suggestion, but.. For You, TBD.. 
This Co. - in addition to selling New Solar Panels / Kit, etc - they redo Commercial solar fields and surplus out the replaced panels (which Still have Plenty of 'Life' left, as they're pulling / swapping panels for 'insurance' / Contract, etc reasons - Not because there's anything "wrong" with them...
..As an Example: Used Solar Panels Archives - SanTan Solar Store ..Such 'savings' on these Panels would allow those 'bereft of Budget' to invest more in Other system-critical things - like Better-qual Batteries / Inverter / Controller / Volt Meters, etc, etc - vs blowing 90% of it on "New" / pristine Panels - then having to 'go cheap' on those Other mission-critical items..
I mean.. https://store.santansolar.com/product/santan-solar-t-series-250w-silver-frame-solar-panel/ ..Yeah - that's Project-Quality-Boosting savings, right there.. (Imo..)
Fwiw..
jd
This Co. - in addition to selling New Solar Panels / Kit, etc - they redo Commercial solar fields and surplus out the replaced panels (which Still have Plenty of 'Life' left, as they're pulling / swapping panels for 'insurance' / Contract, etc reasons - Not because there's anything "wrong" with them.....As an Example: Used Solar Panels Archives - SanTan Solar Store ..Such 'savings' on these Panels would allow those 'bereft of Budget' to invest more in Other system-critical things - like Better-qual Batteries / Inverter / Controller / Volt Meters, etc, etc - vs blowing 90% of it on "New" / pristine Panels - then having to 'go cheap' on those Other mission-critical items..
I mean.. https://store.santansolar.com/product/santan-solar-t-series-250w-silver-frame-solar-panel/ ..Yeah - that's Project-Quality-Boosting savings, right there.. (Imo..)
Fwiw..
jd
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I checked them out, awesome, I have been looking to do some experimenting but the price was out of my budget range, at these prices I could "experiment" with a 1000W setup for under $500.... That could be very useful to me.... Thankyou @SoJer , I never would have thought of used panels......Fwiw (as, not sure if 'Shipping to AK' will negate any possible 'gains', via this suggestion, but.. For You, TBD..
..As an Example: Used Solar Panels Archives - SanTan Solar Store ..Such 'savings' on these Panels would allow those 'bereft of Budget' to invest more in Other system-critical things - like Better-qual Batteries / Inverter / Controller / Volt Meters, etc, etc - vs blowing 90% of it on "New" / pristine Panels - then having to 'go cheap' on those Other mission-critical items..
I mean.. https://store.santansolar.com/product/santan-solar-t-series-250w-silver-frame-solar-panel/ ..Yeah - that's Project-Quality-Boosting savings, right there.. (Imo..)
Fwiw..
jd
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If you do try out the used panels let us know what type of performance you actually get. Solar panels do wear out.
Ben
Indeed, but that's the 'best-kept secret' of That Co - they're 'swapping out' / surplus-selling - Not 5 yr old 'jalopies' - but ones that are like ~ or < 12 mo's Old - Practically 'infants'!
..Again, these (largely) are from Large, Commercial 'Solar farms', where, for 'insurance / contractual-reasons', they Must keep "new" panels in place, every year.. Thus, it's not for reasons of age / 'tiredness', they're selling 'em.. (though they Do also sell 'scratch & dent' ones - But they 'call that Out', up front, ie:
SanTan Solar T Series 240W Cracked Vinyl Solar Panel - SanTan Solar Store SanTan Solar Wholesale Solar Panels ..$40.!! That, and a tube of silicone, and yer off to the races!
Again, Fwiw.. (and No - Not a 'Rep', Not 'shiling', etc.. Just FYIin..
jd
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Thank you. I have them saved for when I add solar to my house, hopefully next year. I will consider them when I get a couple panels for a yard project.Indeed, but that's the 'best-kept secret' of That Co - they're 'swapping out' / surplus-selling - Not 5 yr old 'jalopies' - but ones that are like ~ or < 12 mo.s Old - Practically 'infants'!
..Again, these (largely) are from Large, Commercial 'Solar farms', where, for 'insurance / contractual-reasons', they Must keep "new" panels in place, every year.. Thus, it's not for reasons of age / 'tiredness', they're selling 'em.. (though they Do also sell 'scratch & dent' ones - But they 'call that Out', up front, ie:
SanTan Solar T Series 240W Cracked Vinyl Solar Panel - SanTan Solar Store SanTan Solar Wholesale Solar Panels ..$40.!! That, and a tube of silicone, and yer off to the races!
Again, Fwiw.. (and No - Not a 'Rep', Not 'shiling', etc.. Just FYIin..
jd
Heck, the the price of plywood these days I might consider them for the roof over a horse shelter in the yard, they look cheaper than a few sheets of OSB and some metal roofing and they will be profitable in the long run.
^ 'Multitasking', that's the Ticket! 
jd
jd
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Depending the design of the panels one cracked cell can lilmit the panel output when the cells are wired in series.Indeed, but that's the 'best-kept secret' of That Co - they're 'swapping out' / surplus-selling - Not 5 yr old 'jalopies' - but ones that are like ~ or < 12 mo's Old - Practically 'infants'!
..Again, these (largely) are from Large, Commercial 'Solar farms', where, for 'insurance / contractual-reasons', they Must keep "new" panels in place, every year.. Thus, it's not for reasons of age / 'tiredness', they're selling 'em.. (though they Do also sell 'scratch & dent' ones - But they 'call that Out', up front, ie:
SanTan Solar T Series 240W Cracked Vinyl Solar Panel - SanTan Solar Store SanTan Solar Wholesale Solar Panels ..$40.!! That, and a tube of silicone, and yer off to the races!
Again, Fwiw.. (and No - Not a 'Rep', Not 'shiling', etc.. Just FYIin..
jd
In this video Engineer775 installed second hand panels his customer purchased cheap.
Buyer beware
Ben
Fwiw (as, not sure if 'Shipping to AK' will negate any possible 'gains', via this suggestion, but.. For You, TBD..
..As an Example: Used Solar Panels Archives - SanTan Solar Store ..Such 'savings' on these Panels would allow those 'bereft of Budget' to invest more in Other system-critical things - like Better-qual Batteries / Inverter / Controller / Volt Meters, etc, etc - vs blowing 90% of it on "New" / pristine Panels - then having to 'go cheap' on those Other mission-critical items..
I mean.. https://store.santansolar.com/product/santan-solar-t-series-250w-silver-frame-solar-panel/ ..Yeah - that's Project-Quality-Boosting savings, right there.. (Imo..)
Fwiw..
jd
I did check this out and was interested as the price looked decent. Unfortunately when I put in our address, this is what it said:
“There are no shipping options available.”
I’m pretty used to that!
I still haven’t made it into town to visit any distributors and now I doubt I can visit until August. Summer work activities are taking a higher priority.
I agree, I want to make one in the yard to use for quickly heating the pool in the spring, that would allow swimming a month or two sooner around here when the days are 80* but the nights are still in the 30's, I would also like to use it for heating a hot tub for the yard if I ever get one. But, adding a cob bench to warm up will also provide a comfortable place to relax in the yard during the cooler months. If someone lived in an area with very cold winters and had a place in their off grid home I think the RMH could be helpful for them, but it isn't for everyone.
The Cels, themselves, are Not cracked - just the 'vinyl wrapper' on the rear.. From their Own desc:
"Panels have been tested and have good output. The vinyl has airside cracking (backside), but have no signs of any moisture intrusion on the panel. The EVA moisture barrier appears to be intact"
..and they Still Warranty those for a Year (Their own Warranty - not the Manufacturers '10/25', since these Are "used", afterall..) so.. Doubt they'd be Offering such, if the Cels, themselves, were damaged, mon frére.. Nonetheless, your point is Valid - just not for SanTans's panels.
Again - my only 'posit' with this Source was for those "bereft of Budget", as I posted.. For those 'flush of del casho', well.. Go whole hogg, brand spankin new, cha-ching, bada-bing..
Gaah, yeah, I'm not surprised to hear.. Welp - IF it helps, I am more than happy to discuss (PM if you wish) a 'helping hand', from down here..
..Ergo: You buy, Ship to Us, here (CA); I Professionally Re-Box / crate to 'survive the trip Up, there' (and, Trust me when I assert: I Know how to 'box for survival' - I've shipped Glass and glass/ceramic Laser Tubes to Europe / Australia / Russia, and points-thereof, so.. Can-Do..
) - and then we have your favorite 'Freight Forwarder' take it the last-leg, up to ya.....I mean, I've Got to believe there are Many reasonable options for Freight, from Lost Angeles > Los Anchorage.. amirite?
I should think, anyway..Well, give it some thinks; Offer is on the Table - NO 'strings', NO 'cost' (other than materials to box / crate, etc) and maybe a $20-spot for Diesel to drive down / drop at the Docks, down Long Beach-way..
Either way, Fwiw..
jd
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That sounds better.
Years ago there solar panel companies offering to put panels on tour roof for free pluss give you free electricity and hey would collect the money from back feeding the grid for 3 years. After that the panels were yours to keep. But after 3 years the panels were junk.
That was maybe 15 years ago in CA.
Ben
Years ago there solar panel companies offering to put panels on tour roof for free pluss give you free electricity and hey would collect the money from back feeding the grid for 3 years. After that the panels were yours to keep. But after 3 years the panels were junk.
That was maybe 15 years ago in CA.
Ben
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Well I am on my way to a brighter future. I ordered enough supplies to make a 400 watt stand by-power power backup.
I am not sure about exactly how I will set it up but I am thinking of a sliding plane (similar to the multi-level chalk boards at the university) that can move 2 banks of panels in and out of a stored position. I hope to use it to keep a bank of flooded batteries charged so I can use it to power the wife's medical equipment in a pinch, I would like to design it with ability to expand to cover a couple of freezers.... but that is down the road a bit, for now I want learn all I can so I will be able to act intelligently going forward.
I am not sure about exactly how I will set it up but I am thinking of a sliding plane (similar to the multi-level chalk boards at the university) that can move 2 banks of panels in and out of a stored position. I hope to use it to keep a bank of flooded batteries charged so I can use it to power the wife's medical equipment in a pinch, I would like to design it with ability to expand to cover a couple of freezers.... but that is down the road a bit, for now I want learn all I can so I will be able to act intelligently going forward.
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It would be best for you to get an MPPT controller for your system from day one.
Here is a lightweight solar setup I had running a couple of days ago that demonstrates the benefits of an MPPT over a PWM controller:
The panel is supplying 1.8 Amps at 16.5 Volts. That is too much for safe charging of the battery, so the MPPT controller is dropping that down to 13.1 Volts. But it is also converting panel power in a way that boosts charging current to the battery to 2.3 Amps.
So the MPPT controller is charging the battery 28% faster than a PWM controller would.
Thanks for that great suggestion. Another thing for me to research.
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Here is the rest of that system running. It is not really a solution for a homestead, but it can run loads of 1-5 Amps at the right time of the year.
The battery (30Ah LiFePO4) weighs about 8 lbs and is rated for 8000 cycles to 30% (WOW!)
The panels each weigh 2.6 lbs - with two of them in full sun they can charge the battery to 100% from 30% charge in under 3 hours.
https://www.powerfilmsolar.com/media/products/60_Watt_Foldable_Solar_Panel_Spec_S_274E48335C594.pdf
The controller is an EPEVER Tracer 2606BP with an MT50 interface unit.
That controller is IP66 waterproof, user configurable and Lithium capable.
Notice I use heavy cables and 50A Anderson plugs for all the modular connections. The inputs and outputs cover Anderson and male and female cigarette lighter types.
The output can be drawn through the controller (and hence be monitored from the MT50 and limited as to how much it will take from the battery) or just connected directly to the battery.
Believe it or not, but that system will run a 2.8 cubic foot camping freezer and it can be carried in a backpack.
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I will have to be able to keep my panels below the fence top most of the time. I have a number of parts including a MPPT controller in the drawer, but when I looked at the component prices I was able to basically get the PWM controller for free with the kit, so I want to see how the two deal with shade and things like that, I will have enough fittings to go series, parallel or series/parallel, but having the option to try them all is nice... After all I am using this as a learning tool to grow with.....
I was just real happy that the wife said okay before the sale was over.
I was just real happy that the wife said okay before the sale was over.
If the grid crashes, I plan to use a copper coil inside of a big container to capture heat from my wood stove, the coils around the flue are efficient, but also have the potential to create steam pressure and explosions. the water pumping solution could be a generator driven submersible combined with a cistern and a low voltage pump. There was a guy on prepared society that built a 200 plus foot hand pump
These are amorphous silicon panels? How do you find the performance compared to monocrystalline?
Thanks
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Correct.
I don't think anyone makes fully flexible mono crystalline cells. There are some semi flexible mono panels around - but not so flexible they can be folded and soft mounted.
The way that powerfilm wire them makes them handle partial shade better than most. They use a series in parallel method that also creates redundant current pathways that maintain some output even if the panels get quite damaged.
They have bigger area but overall less weight and more compact than if they were mono.
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I have all my parts together to make a working system, we have Ida on it's way and I want to be ready to set up a temporary system.
I was thinking of an array of ground mounted panels. Then I did the math for a 24" tall panel in the winter time and realized that for 2 rows of panels at optimum angles I wild need a 12' wide space, so I think the design will need to by 1 row 48" tall. I am thinking of a simple mount that I can drop panels into and lock them in place with a clamp at the top and then swivel them into position.
Don't have the time to do much on it right now, but I am gathering my thoughts and when I can fully visualize a design I will be making it.
I am planing on placing a small unit outside to evaluate using the power for useful things, I have a Kill-o-watt device now and plan to measure the draw of my grow lights, to see if it might be possible to have my indoor winter garden solar powered.....
I was thinking of an array of ground mounted panels. Then I did the math for a 24" tall panel in the winter time and realized that for 2 rows of panels at optimum angles I wild need a 12' wide space, so I think the design will need to by 1 row 48" tall. I am thinking of a simple mount that I can drop panels into and lock them in place with a clamp at the top and then swivel them into position.
Don't have the time to do much on it right now, but I am gathering my thoughts and when I can fully visualize a design I will be making it.
I am planing on placing a small unit outside to evaluate using the power for useful things, I have a Kill-o-watt device now and plan to measure the draw of my grow lights, to see if it might be possible to have my indoor winter garden solar powered.....
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I would keep the low edge of any panels a MINIMUM of 24 inches off the ground. All our panels are adjustable for angle so I can catch the optimum sun angle at any give time of the year. Which is something you may want to consider also.
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Do you have a tool or way the ensure that you are at the optimal angle? I was thinking of installing a dowel or tube perpendicular to the mounting plane to act a an aligning guide... but that was just a thought>>>
There are online guides where you enter your location, and it spits out your angle for a given time of year OR what the best average angle will be in your location for panels that don't move.
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I'm sorry I wasn't being clear, I want to set up a system that I can quickly deploy in power outage, but be able to remove it and place it back in storage just as quickly. I have the guides but would love to be able to do a quick line of sight alignment and walk away. I am thinking of being able to deploy about 400watts in under 15 minutes..... that kind of complicates things.
We use one of these to set the angle when we adjust depending on the time of year. You could probably find such a thing on Amazon I'm sure. Quick way to check the angle.
https://www.leevalley.com/en-ca/sho...-box-ii-digital-inclinometer-for-tool-setting
I don't think you would need anymore than your eyeball for that. Playing with my 200 watt system, just generally angling it towards the sun works fine. I've played with doing it more precisely and only noticed marginal differences in daily power output. Compared to things I can't control, like the weather, the angle seems to have little effect as long as its more or less in the right direction. Even just laying the panels flat in a sunny spot seems to work almost as well as the tilting mount I eventually built.
Angling enough to shed snow by themselves in the winter seems to be more important than sun angle as well. I stick mine almost vertical in that season, which is not the optimal angle for my area, but snow build up has even more effect than angle.
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A carpeters square laid on the panel with the short leg pointed at the sun. Adjust angle for no shadow.
Ben
