Off-grid rural Upstate NY needs help ASAP for minimal heat

Dee

Posted on my activity in error and not sure anyone will see it.

With limited funds I’ve been getting by but my needs have changed with the seasons.

Have been alternately using two 12v auto batteries and recharging on standard battery charger which requires taking them off of my property (not practical), running 7w LED + 60w incandescent lights, and 30,000 btu propane heater fan. My electrician friend suggested a parallel array with solar panel to keep it charged.  I have experimented with three different inverters, a 400w emergency made to connect to an installed battery which gives the longest run time. The other inverters are labeled “solar/sine wave” (2000w/900w continuous and 3000-4000-5000w), and work just drain the battery faster.  The larger inverters power much higher draw items successfully yet not for long and do not give equal run hours to the smaller 400w inverter when running just lights or heater fan.

With hot and humid summer, and cold snowy winters, the use will be different. For now I want to run a 750w heater with thermostat on lowest setting to keep above 48 degrees in a mobile home. I’m planning to set the battery array inside a fiberglass tub not connected to a water source for added safety. The panel will be vertically installed (facing due south unobstructed), a 25w solar panel with 100w regulator that have been purchased from Harbor Freight and I would appreciate any advice to install a safe and adequate system to get through the winter.

Thanks for your help!

bill von novak

OK first don't do this:

Dee said:

a 25w solar panel with 100w regulator that have been purchased from Harbor Freight and I would appreciate any advice to install a safe and adequate system to get through the winter.

Thanks for your help!

There are far better sources for much better equipment.  (Like the parent company for this forum, Northern Arizona Solar.)

Smaller inverter - you're on the right track there.  The smaller the better, and the lower quiescent current the better.

BB.

For a small off grid solar power system--Conservation is key. Get rid of the 60 Watt bulb and go with 120 VAC LED bulbs, or even 12 VDC LED (12 volt track lighting bulbs, drop the transformer).

And, unfortunately, the fan on your propane heater is "not great" for a small solar powered system... A radiant heater would be better, if you can swing it (or other non-fan type heater). I would suggest a vented heater--An unvented heater in a sealed home can add a bunch of humidity to the air--That may be a good or bad thing for you--roughly 1 gallon of water vapor per 1 gallon of propane burned (plus they use up the oxygen too).

Battery wise, a pair of 6 volt @ 200 AH batteries in series (12 volt @ 200 AH) is a good small battery bank (relatively cheap at ~$100 per battery and relatively forgiving).

AC inverters--I am a big fan of them, but for smaller systems, the (typically around 6 Watt "tare losses") can be a killer (running 7 Watt AC light and another 6 Watts just for the inverter).

In any case, to be helpful, we need to know more about your loads and overall energy needs. And your budget (solar is not cheap) to figure out where to put your money.

Things like 4x 7 watt lights for 5 hours per night (4 * 7 Watts * 5 hours = 140 WH per night; 100 Watt fan for heater * 5 hours per day = 500 WH). And running solar in upstate New York in the winter is a tough road:
http://www.solarelectricityhandbook.com/solar-irradiance.html

Burlington Vermont
Average Solar Insolation figures

Measured in kWh/m2/day onto a solar panel set at a 31° angle:
(Optimal winter settings)

Jan	Feb	Mar	Apr	May	Jun
3.27	4.09	4.37	4.14	3.97	4.08
Jul	Aug	Sep	Oct	Nov	Dec
4.26	4.30	4.11	3.41	2.55	2.54

Add the energy usage together (140 WH + 500 WH = 640 WH per day), then the solar panel required would be:

• 640 WH per day * 1/0.52 off grid system eff * 1/2.54 hours of sun December = 485 Watt solar panel minimum

And, assuming this is your "base load" (you need these every day)--I would be suggesting 2x the solar panel (2x485=) 970 Watt miminum array (you cannot use 100% of predicted power every day).

Roughly, a flooded cell lead acid battery bank would be in the range of:

• 640 WH per day * 1/0.85 AC inverter eff * 2 days storage * 1/0.50 maximum discharge * 1/12 volt battery bank = 251 AH @ 12 volt battery bank

That would be 2x 6 volt @ ~220 AH = 12 volts @ 440 AH battery bank...

And just to check, for a full time off grid system, I would suggest a minimum rate of charge of 10-13% rate of charge:

• 220 AH * 14.5 volts charging * 1/0.77 panel+controller derating * 0.10 rate of charge = 414 Watt array minimum

Because you have such poor sun in the winter (when you need the power), your array sized for winter power is > the 10% minimum rate of charge.

Or get a Honda eu2000i (or eu1000i) genset and burn about 1 gallon of fuel per 9-10 hours per day for your winter use... (plus keep the oil changed). You should get >2,000 hours out of the genset.

Anyway, some starting points for discussion.

-Bill

Estragon

Using solar electricity to heat anything is generally impractical, especially in winter.

A car battery might be ~100ah.  At 12v, that's 1200 watt-hours.  At 400w, you'd get about 1.5hrs to 50% capacity.  A car battery isn't designed to be cycled that deeply, and may not last the winter.  Taking it much below that may mean it has problems in a matter of days or weeks.

As a wild guess, it might take 10,000btu/hr to keep a mobile home at 48°f in your location.  At ~3.4btu/watt, that's ~3,000 watts/hr.  It would take a huge solar/battery system to supply a load like that in winter.  

Dee

Thanks to everyone who has responded. 

I have found it difficult to get usage info on many electric appliances. Maybe I don’t know where to look. 

To clarify a few things, the trailer is in need of serious rehab and despite closing off as many leaks as I could, it is still very drafty. Closed up the hole in the roof so it isn’t leaking water/snow but humidity and lack of oxygen aren’t a concern. I’m only trying to heat the back 1/3 as a cat was left there by previous owner and had kittens in there. It’s a temporary situation. Next year I will rehab the trailer and have power turned in. Right now it isn’t possible due to people stripping resources illegally. That is why I thought of using an inexpensive setup. I had already purchased two 12v auto batteries (Walmart $50. ea. W/carry handles so I can take them for recharging). I can buy parallel cables for an array on ebay. 

I requested an estimate from a local solar company with good reputation that attempted to oversell me ($12k is not in my price range). I inquired about making a wind farm and was told it is hard to get permits for. I don’t want to make a solar field in a remote place likely to be stolen from. I was told that without new construction it would be impossible to get permits for solar. My desperation has led to much research with the determination to do it myself. I can’t live there without a new 4wd vehicle, power, snow removal equipment, and someone to find and fix well/septic. Even the pipes have been stolen from the plumbing (hence no water to the tub).

The back room is about 16’x20’ and fairly well insulated. The 16’ wall faces due south with no openings. I was going to put one cheap panel there where it won’t be visible. I have battery operated motion sensor lights. The 7w is really two 3.5w solar grow LED light arrays that throw good full spectrum light. The 60w is a bug lamp used in the garage and kept away mosquitoes in the summer when I worked long past dark. It’s too cold now for that and just the two 3.5w light last a full week or more on one battery. 

I like the good info on this site and am still learning. I was hoping to find a suitable heat source to keep the cats from freezing that is low maintenance until spring thaws the snow. This place doesn’t get normal upstate thaws in winter due to 1200’ elevation. It will soon be impossible to reach. Gravity feeders and waterers still need the temperature to be above freezing.

 I think that I must rethink the situation and take the kittens to a shelter. They are a little wild but healthy and amazingly smart. They are being trained by mom to mouse and without them the place will be overrun with mice by spring. Anyone offering a forever home for a kitten please respond!

In the meantime, for the next few weeks I need some heat in there. The cabin I’ve been building will be entirely off the grid and why I was looking into solar in the first place. 

Still appreciate advice on solar and $500. more is beyond my budget. I have seen used systems offered but don’t trust sellers to be honest. I have been burned enough buying used things I wasn’t sophisticated about.

Dee

Please forgive my typos...

mike95490

An electric heater running off an inverter and batteries you can carry, is dead battery in a couple hours.   Possible solution is a small animal proof electric blanket or warming pad & a small inverter.

A 12V 80ah deep cycle battery contains 960 watt hours, half of which are usable.  So you have 480W to play with, for 12 hours before you recharge, that's 30 watts of heating pad  & 10W internal losses in a small 100w inverter

Automotive batteries will only last you a few weeks before they fail in deep cycle usage.  you could use 2 golf cart batteries wired in series to get 12V. Those are usually 6V 200ah rated.

oil pan 4

Don't buy any solar related stuff from harbor freight ever. It's the cheapest junk they could possibly find sold at the highest prices imaginable.

Forget about running anything off a 25 watt panel. Those are pretty much battery tenders. You could use one to power an electric fence maybe, or a motorized gate that sees occasional use.
You couldn't even power an electric blanket with a 25 watt panel.
Not a heater.
How did you ever think you could power a 750 watt heater with a 25 watt panel?
Do your self a favor, get a hammer and smash that electric heater.
Even charging the batteries some where else is only going to provide minutes worth of heat per charge.

Your only chance is propane and/or electric blanket.

Photowhit

I'm going to reply in graphics, This is my solar array outside my mobile home;



This is my heat source, as I installed it as part of my solar conversion;


This is a year later, staying warm, with a hot toddy and wood stove.;

Estragon

An alternative to heating pad might be some self-regulating DC water line heat tape:  
https://www.oemheaters.com/category/983/freezstop-12-and-24v-heat-cable

It could run off batteries directly, without an AC inverter.  In a small box, it may supply warm-ish refuge within the limits of a luggable set of batteries.

Kittens tend to be more adoptable than grown cats (especially semi-feral ones), so the best thing for them might be the shelter.  I'd take one or two, but the ~2500mi drive is a bit much.

NANOcontrol

My summer camp is likely not that far away.  I live quite well there till October nears.  I can barely keep just the fridge running with 2.5KW of panels in October.

Dee

I understand what everyone is saying and though my heart is breaking my thoughts have turned to seeking homes for the kittens. Somehow the mom survived last winter there all alone. I didn’t realize it until spring. My friend believes they will be fine and said he will go every week to check on them (he has a 4WD truck).

Love the pics, photowhit! I would love a setup like that!

I like the idea of the thermal tape and it might work on the extra large gravity waterer. Low wattage heating pads for pets are available and might be possible as well.

My smallest inverter runs up to 400w devices and the fan is very quiet. I imagined that if on a timer to cycle for four hours the solar panel might be enough. Given the overall quality of what H.F. sells, I’m sure the assessment here is correct. I thought their 100w panel was overpriced. I’m also afraid anything decent will be stolen so I am hiding a solar trail cam for security. Lol I paid twice the price for it than the solar panel, which I can return. 

How can I evaluate the quality vs price issue?

Estragon, I might be driving past you on a trip to Seattle. If you are serious it might be possible. If you know how to message me and are serious please do. I’d happily share pics.

Dee

It was 26 degrees outside two days ago, and inside 30 deg. when I arrived to frozen water dishes. I ran a 30,000 btu propane heater for 4 hours in the opposite end of the trailer and reached 50 degrees there. The far end with cats reached 38 degrees. I got a much larger bowl to hold a gallon for them. They had ventured outside before I arrived —  footprints in the fresh snow surprised me. Once warmed up they were playing but cleverly snuggled up after I turned off the heater. I would never try to leave a propane device untended. 

The temperature is back up in the 40s during the day now that the storm has passed but more and harsher storms are certain soon.

Tomorrow I’m going down again and will snap some pics. Please don’t think me inhumane...if I can’t come up with a reasonable and safe solution then they will need to be relocated. If so kittens are easy to love and I will take Dolly, the mom cat, with me to Seattle.

Now that has to be goid for a laugh... a partly feral cat in the car fir 2900 miles! Does that top buying solar from H.F., or what? 🤣

mcgivor

Don't underestimate the resilience of animals, they have survived thousands of years without our help, food would be more important than heat, without which they cannot produce body heat which they can share. They  are also provided with winter coats, thanks to nature, it is noble of you to be concerned for their well being, but a good meal every week, or more frequently, would be more valuable than temporary warmth, probably cheaper too, as long as they are protected from wind they'll probably be fine.

Estragon

Depending on your route, I'm afraid it'd be at least 500mi out of your way plus crossing border, so not really practical.

Animals are amazing.  Last January, walking past a bit of river kept open by current flow despite temps of ~-30° and a brisk wind, I saw a duck splashing around in the water.  I thought it was done for, but it was still there splashing for the next several days.  My guess is it was staying warm in the sub-freezing (but still much warmer than air) water!

Dee

Thank you Mcgivor and Estragon. I have two friends offering to go by one each week and one every other week, both encouraging me to let the cats stay put. They would likely hike a city block wading through snow so it is quite a noble sacrifice. Obviously both love cats and recognize that these are indeed special. I’m planning to leave a 6-8 week supply of dry food in a gravity feeder.

Another friend thinks hooking up my well is the most important thing. That requires a substantial investment which isn’t practical if no one is living there, and might encourage squatters. I’m convinced that at the point the property is habitable, PV is the way to go. I just can’t do it until next year.

I bought a dc pump that connects directly to a battery but the power drain would still not keep the battery working for months without recharging. I need to check pump specs, but on a trickle charge it could recirculate a larger amount of water to prevent freezing. Filling a fifteen gallon galvanized tub or bathtub and keeping water moving might last for four to five months, and could be monitored by friends. I also have a 50 gal water barrel with spigot.

Yesterday over a foot of snow made it rough to get to the trailer. It was 30 deg outside and the temp inside was 37 deg. I was amazed that it held so much warmth. Still there was half an inch of ice at the bottom of the one gallon plastic bowl. I dumped and filled with fresh water, noting a frozen 3 gallon bottle near the outside wall, while a 1gallon bottle on an inside wall had no ice at all. Placing a solar panel outside would locate power nearer the exterior wall which would mean moving the water also. Moving the panel to reach the center of the trailer would give a choice of east or west side as the 100’ length runs due north-south (see profile pic). The cats’ room is conveniently at the south end. Hanging vertically on the side is the only option as it would otherwise be buried under snow.

Estragon, I’m going roughly from Syracuse to Seattle on the northern route, making only certain points available to cross the border. With nearly 3k miles to go already, adding another 30% taking into account getting back on track doesn’t seem wise. It would cost less and be easier to ship a critter, unless you wanted to meet me at the border!

For those interested in the power situation, despite disconnecting the battery from the inverter and the heater fan running strong at the time of disconnecting, it failed to start yesterday. The battery ran the inverter but I suspect that it was well below the 50% threshold and removed the battery to recharge.

I’m considering keeping the HF panel and connecting to a parallel two-battery setup with the regulator (panel says specifically designed for motor home or camping when connected to an inverter and two parallel batteries with the regulator for ac current). If it could trickle charge the two batteries then they might hold enough juice for the heat cable and possibly the dc pump to prevent drinking water from freezing until spring.

From what I’ve read, one or two batteries won’t last four months even with the slight drain from the heat cable. Seems to me that the panel claiming to give 25w per hour might only be expected to give half of that in the extreme conditions, perhaps only 10% and for 4-6 hours a day depending on cloud cover. Am I close to the right thinking there?

Estragon, one question is what size of heat cable might be expected to keep water thawed if the trailer reaches near zero even overnight? The 9v per foot cable at 3’ long is what I was thinking to wrap the galvanized tub around the widest part. I just don’t know if that will keep the whole thing from freezing and wonder if the absolute cold effects the performance of cable/batteries? Should the cable wrap twice? Or might a 5v per foot cable once around bring up temp enough to keep from freezing?

This coming week will see a few days where temps reach highs in the low teens and will give me a little time to find a solution. I’ll be checking back for everyone’ s wisdom and suggestions. I’m also browsing other threads to increase my knowledge. I’m so glad I found y’all!  

Dee

Photowhit said:

I'm going to reply in graphics, This is my solar array outside my mobile home;



This is my heat source, as I installed it as part of my solar conversion;


This is a year later, staying warm, with a hot toddy and wood stove.;

Dee

Photowit, are you in Cortland County?

Dee

oil pan 4 said:

Don't buy any solar related stuff from harbor freight ever. It's the cheapest junk they could possibly find sold at the highest prices imaginable.

Forget about running anything off a 25 watt panel. Those are pretty much battery tenders. You could use one to power an electric fence maybe, or a motorized gate that sees occasional use.
You couldn't even power an electric blanket with a 25 watt panel.
Not a heater.
How did you ever think you could power a 750 watt heater with a 25 watt panel?
Do your self a favor, get a hammer and smash that electric heater.
Even charging the batteries some where else is only going to provide minutes worth of heat per charge.

Your only chance is propane and/or electric blanket.

Dee

My thinking was a four battery parallel using 25w per hour panel on a regulator to keep a trickle charge, though even at lowest setting on the thermostat it might stay on most of the time. I’m not looking for human comfort but to keep drinking water from freezing. The heater is excellent not old but older tech, and uses such a small amount of power that it is barely noticeable on an electric bill. It has high and low power settings plus a rotary thermostat. No smashing happening and for human habitation can keep cozy on low with thermostat at about 25%.  I have a newer ceramic one with the same power draw that is 1/8 the size much quieter and keeps comfortable with less run time. Both could keep a 1200-1500 sq ft space tolerable with relative ease and low cost. Personally I tend to only heat the space I’m using which either achieves in 5-10 minutes then sporadically turns on only every 40-60 mins for a few mins.

As one who has minimal experience with batteries and inverters, and none with solar, I’m still smart enough to seek advice.

The ambient temp of 30 degrees doesn’t seem to bother these cats one bit but keeping fresh unfrozen water is my greatest concern.

Why keep the cats?  Mice, rats, and/or squirrels would likely overrun the place by spring!

LOL. I’m totally with you on less is more, but too many heaters without fans cause fires... something I really can’t afford!

Photowhit

Dee said:

Photowit, are you in Cortland County?

No, Central Missouri.

Dee said:

As one who has minimal experience with batteries and inverters, and none with solar, I’m still smart enough to seek advice.

Glad you are asking questions. 

westbranch

I think you need to go Low tech for this one...

Do you have a 'dog house' like structure for the cats?  ( "CAT HOUSE " has too many other connotations! )

Sounds like 3 cats total so max 3x3x3  foot cube with a 'curtain like cover on the entry and insulated inside on all faces with at least R10 styrofoam sheeting should be more than adequate.  You would want to have a scratch free surface to protect it from those kittens.... our Malamute dogs used to like it outside in winter to -40C/F (same temp)  in a dog house that  had R 15 and a mat on the floor..  Noses always stuck thru the 'door'.

hth

Dee

westbranch said:

I think you need to go Low tech for this one...

Do you have a 'dog house' like structure for the cats?  ( "CAT HOUSE " has too many other connotations! )

Sounds like 3 cats total so max 3x3x3  foot cube with a 'curtain like cover on the entry and insulated inside on all faces with at least R10 styrofoam sheeting should be more than adequate.  You would want to have a scratch free surface to protect it from those kittens.... our Malamute dogs used to like it outside in winter to -40C/F (same temp)  in a dog house that  had R 15 and a mat on the floor..  Noses always stuck thru the 'door'.

hth

Dee

Guess I am not doing the reply thing correctly here...

the cats are inside of an insulated mobile home, and I’ve set them up a nice ‘bedroom’ in the master bdrm closet, with a dog bed on top of a thick wool rug, cat tree, and a plastic igloo with an insulated cube inside for a bed. They have rugs outside of the closet and fleece throws for coziness. I’ve covered all the windows and thier litter is 5 boxes in the next bedroom. They seem to love their habitat and have a fairly safe emergency exit through the former furnace spot (looted), and I’ve set an old lace curtain on top of the steel floor pan with a battery operated motion sensor light that turns on when any come in or out. Lol There are five kittens plus the mom. I probably worry to much but temps do reach -40 or less in winter.

They probably would shred foam... they play with everything including pilulling insulation out of the walls where they can. Anyone who even likes cats a little would be charmed by these amazing critters. I actually think they mught have a little Bengal cat in them from various physical traits and markings. 

For those who didn’t know, the Bengal cat is a unique breed of cross between a big cat and domestic that at 50/50 has a high degree of genetic deformity yet not always. I would guess the mom to be maybe 25% of the blend. One of the kittens has more distinct traits physically speaking and is the most resistant to me. I did pluck a far deer tick from her eye the first time I caught her but she is definitely the hardest to catch. She was the same size as the obvious runt but now that Ive been feeding them they all are most excellent in health and griwth. Ive also dosed them all with Advantage Plus at 8 weeks old. 

The few friends who have seen them have fallen in love with them. One wanted to take two home and his wife said no way (hemight like them more than her). 

The idea that they end up in cages or an overcrowded shelter is horrible, but getting gassed at the SPCA is unbearable. I’d rather let them live out their natural lives taking their chances with predators. My daughter thinks I’m the inhumane one. 

Low tech it will be and with the help of friends who also would rather see them stay there than get put in a shelter they should be alright.

Estragon

Crossing the border to get cats is likely to make US and/or CDN border people assume I was using them as cover for something more nefarious.  Probably make for an unpleasant day (for me, possibly very unpleasant for the cats).

Heat tape is normally designed to keep a pipe at just above freezing.  I have a single line attached to 1" plastic waterline through ice to lake, wrapped in closed cell pipe foam like what might be used for a domestic hot water line.  It's just a backup to a pressure drainback, but I've used it to melt frozen line in ~1/2hr.  For larger pipe, it would normally be wrapped in a helix or double helix to increase watts/ft of pipe.  

In this application, you'd need to work out how much needed to keep the waterbowl space warm.  Using Westbranch kennel idea, a 3x3x3 cube would be 9sq.ft./side x 6 sides =54sq.ft.  Say 40° kennel temp minus 0° ambient.  R2 (U=1/2=0.5) plywood box.  54x40x0.5=1080btu + opening for curtain.  1080btu÷3.4=318w.  With R10 (2" foam), 54x40x0.1=216btu +opening.  216btu÷3.4=65w.

Another thought, box a waterbowl with foam/plywood.  Say 1cu.ft.=6sq.ft.  6x40x.1=24w (plus loss through an opening so they can get to the water).

Just kicking a few numbers around.

Dee

Ty Estragon!

Dee

Update: four kittens adopted, one left with mom...might be taking them on the cross country trip instead of leaving them in frozen tundra (lol or the trailer)!

Still intend to setup solar power in the spring and wil have much studying to do in between. 

Thank you all for your input...I will be rereading until it all makes perfect sense!

Dee

Dee

Trickle charge to the two 12v batteries not leaving inverter connected - just need to run it about an hour per week.

Next pic mu homemade gravity feeder for dry food. Using battery operated air pump in a gallon bowl of water with fingers crossed.