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Most efficient heating blankets, space heaters, hot plate and small fans?

Thegreywizard

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May 12, 2021
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I always like to Be Prepared and once our emergency battery backup system is installed, there are a few other things I want to add to this system to be self-sufficient in a time of need when the power goes out.

The system will eventually be a 24V system, but we're starting off with 12V setups as we build everything out and upgrade to the 24V eventually. We will have a 3000W inverter.

So I really want to get a few high-efficiency things to make life easier in the summer and winter months during power loss.

Heating blankets - can anyone suggest high quality ones that are efficient and work well? I know these can potentially have a large draw on them because of the heating coil.

Space heaters - just looking for a small one that can heat a single room and doesn't pull a ton. I know these can be energy hogs, so what's the best option out there? These can also be really cheap in general in quality, so I would prefer something that is of higher-quality if I'm going to rely on it for emergency back up.

Hot Plate - I know these can be a huge draw, but also a crucial piece of kit if you need to heat or cook something. What are the best, most efficient options for an emergency backup hot plate?

Fans - these don't need to be large, probably 8-12" would be sufficient to keep you cool in the summer and not be much draw I wouldn't think? I suppose any fan from walmart may do? Would prefer a high-quality one though that would be as efficient as possible.

I'm not sure if it's worth going as big as a box fan?

Thanks for your suggestions and input.
 
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Space heaters - just looking for a small one that can heat a single room and doesn't pull a ton.
All resistive element heaters (be they oil filled, fan heaters, convection style, radiators etc) are pretty much are all the same when it comes to energy draw / efficiency and heat output. In N America on ~110V AC systems usually these are limited to ~1500W. In 240V AC countries they tend to be 2.4kW units.

The only sensible way to get more heat from electrical energy is to use a heat pump reverse cycle air conditioner.

Heating blankets - can anyone suggest high quality ones that are efficient and work well? I know these can potentially have a large draw on them because of the heating coil.
I don't know about loose heated throws/wraps, but the sort of electric blankets that fit over bed mattress don't really draw all that much power (less than 100W), an order of magnitude less than a resistive element space heater. They rely on the bed covering providing a well insulated environment to keep heat losses to a minimum.
 
Yeah I know those heaters are the worst. But a necessary evil if you want to heat a small room.

I was doing some more research and did find people suggesting those 12v heating pads and these are them:


That's probably going to be the best option for low draw with good output. Combined with a 100% lambs wool blanked and/or a down blanket should create nice warm cocoons.
 
Induction hot plates are more efficient than regular electric hot plates. However, I do not know if they are efficient enough to justify the greater cost (maybe $70 vs $20 for a single burner), and the need for special cookware. Would their greater efficiency make a difference in real world use? Maybe some math nerd can help us out here. I am following this thread with interest, as putting together a set of efficient emergency supplies sounds like a great idea!
 
as putting together a set of efficient emergency supplies sounds like a great idea
An emergency supply doesn't need to be efficient, just work for the duration required. Efficiency helps but in and of itself is not the highest priority.

e.g. for cooking/boiling water perhaps consider a camping gas stove with a store of portable gas bottles. It's significantly less thermally efficient than induction but it can help to extend the time stored electrical energy will last for everything else.
 
Ahh I like that induction hot plate idea much better!

I don't mind spending more now to get a better setup.

I found this Duxtop that seems to have a very high customer rating. They have a cheaper model, but this one has a nice slanted control panel keeping them away from the pan:


I plan on having something like a rocket stove and or a propane stove as well, but I wanted my main setup to be efficient electric that I can use my battery backup for.
 
The induction stove is great, we call it science stove. Just have a compatible pan and pot handy. It will boil water faster than some gas stoves, gets all the energy into the food and is temp controllable. We used one with a human feedback loop holding a coffee thermometer and once you get it set for 135deg, you can get warm water and throw steaks In for 3-6 hours to sous vide. Then open and sear and perfection!

it ran easily off my old magnum 2412. as far as a heating blanket... eh, might do better with a chicken or lizard warming lamp, you could heat a small area very comfortably for several people. We had a portable heater that did 400-800-1500 watts. the 400 setting heated the smallest bathroom ever. 800 kept a tiny bedroom livable, 1500 kept a section of a living room less cold. It’s really more about your house than anything.

run a test, get a room on a cold night, run a small heater like 4-600 watts. Use a kill a watt or something to keep it honest. See how many degrees above the rest of the house it keeps you. Know that to double the temp difference likely requires 4 times the wattage. the infrared radiant heaters will hit you with heat like a campfire (but softer) making sweatshirts indoors with freezing outsides bearable. Till the batteries or gen gives out at least.

so blankets...
 
Just make sure with an induction cooktop you have the power capacity with your backup power system. If it's a plug in style then it should be rated no more than a typical plug in power outlet can supply. Portable units where I am draw up to 2.4kW.

Check how they operate. Rather than reduce power when you turn the heat setting down, many operate by duty cycling on/off at full power with the frequency of duty cycle adjusted for the desired heating level (similar to how many microwave ovens operate), while the pot/pan manages the thermal equilibrium for heat delivery.

My home induction cooktop requires a 240V 32A supply on its own circuit. Two of the four cooking zones are capable of up to 3000W draw, the other two 1400W each. I excluded it from our backup circuits. If we need to cook I'll use the camp stove or the propane BBQ.

A better option is an electric slow cooker. That can do most of its cooking work during the day when solar PV is available.
 
Just make sure with an induction cooktop you have the power capacity with your backup power system. If it's a plug in style then it should be rated no more than a typical plug in power outlet can supply. Portable units where I am draw up to 2.4kW.

Check how they operate. Rather than reduce power when you turn the heat setting down, many operate by duty cycling on/off at full power with the frequency of duty cycle adjusted for the desired heating level (similar to how many microwave ovens operate), while the pot/pan manages the thermal equilibrium for heat delivery.

My home induction cooktop requires a 240V 32A supply on its own circuit. Two of the four cooking zones are capable of up to 3000W draw, the other two 1400W each. I excluded it from our backup circuits. If we need to cook I'll use the camp stove or the propane BBQ.

A better option is an electric slow cooker. That can do most of its cooking work during the day when solar PV is available.
Problem is slow cookers are limiting culinary wise. The single burner induction at 1600 watts (ours) can fry, boil, sous vide, grill, etc. a typical one burner meal for us is sous vide the steaks, set aside, cook a pot of rice and set aside, fry up some vegetables in some sort of tangy sauce, and set aside and switch to a skillet and sear the steaks. Whole dinner is served warm. If you don’t have the batteries to swing it, then either eat earlier or there is always the slow cooker (or induction with a pot on it)
Also, every Asian store I’ve been to has the little butane single burner stoves for cheap. They’re actually pretty nice if a bit anemic on heat. Makes a good side burner or back up if the electric quits.

our induction seemed to be a pwm on top of maybe 5 power levels, so on low it ran power 1 and just chirped on every few seconds. On med high it might be on 4 with a 50% duty cycle. We learned the lower powers meant lower max wattage when it was on, and could use other appliances still without upsetting the inverter. The induction with a pot on it in this fashion is a low wattage all day slow cooker, while still being able to be more.
 
Problem is slow cookers are limiting culinary wise.
Our slow cooker can fry and grill as well and we use it to make omelettes and have fried sausages in it.

That said, my point was for cooking food during extended outages (this is a thread about backup) they are a relatively lower power device and can do the bulk of cooking when excess solar PV is available, rather than cooking in the evening when you are relying on stored energy.

Also, every Asian store I’ve been to has the little butane single burner stoves for cheap.
That's what I was referring to. Portable camp stove with aerosol sized butane canisters. I have a 6 pack of the canisters in the cupboard. We've used it at times mostly to boil water in a kettle and it works really well. I've been surprised at how long the canisters last. Can pick the stoves up at a hardware or camping store in Australia for $A20 and I'm sure they'd be even cheaper in the US. Or second hand for next to nothing.

We have propane BBQ as well and I'll usually have lots of propane on hand but here we can be outside on a Winter's evening, not so easy in some places where you need to be indoors.
 
our induction seemed to be a pwm on top of maybe 5 power levels, so on low it ran power 1 and just chirped on every few seconds. On med high it might be on 4 with a 50% duty cycle. We learned the lower powers meant lower max wattage when it was on, and could use other appliances still without upsetting the inverter.
Yeah that's good.
Just good to know as not all are the same, worth checking how a backup system copes with their power demand.
 
I have excess solar power (and battery capacity) most days so have been playing with ways to make use of it.

Electric cooking: a 150w/75w crockpot sees the most use (bread, cornbread, beans, lasagna, meat loaf, boiled eggs, etc). I also run a 300w rice cooker and 300w mini hotplate (laboratory surplus). I only cook with electricity "off the panels", without dipping into battery capacity.

Electric contact heating: I've had good results with heated mattress pads , electric vests, and electric heating pads. Last night at 10k' it was in the 40s so I ran the mattress pad at the lowest level (~13w). I also run it in the daytime in cooler seasons for the dog's enjoyment.
 
Heating blankets - can anyone suggest high quality ones that are efficient and work well? I know these can potentially have a large draw on them because of the heating coil.
Get a mattress pad. These are fairly low wattage. Shop around.

https://www.bestreviews.guide/low-voltage-heated-mattress-pad?

https://www.amazon.com/dp/B001JEPSSA/

"Soft Heat products operate on less than 25 volts, the current it takes to illuminate a light bulb. This low-voltage technology includes a small power supply box that changes 120 volt AC home current into non-hazardous low voltage DC current (very similar to a battery) to provide warmth, protection and safety even if the mattress pad becomes wet."
 
Has anybody checked into recirculating showers: https://orbital-systems.com/how-it-works/

This is an example of what I'm going to "DIY", not planning to sell or buy. It looks way out of my price range and has proprietary consumables such as filters/expensive up keep. But with a little community development/using readily available products it might be a thing.
 
Has anybody checked into recirculating showers: https://orbital-systems.com/how-it-works/

This is an example of what I'm going to "DIY", not planning to sell or buy. It looks way out of my price range and has proprietary consumables such as filters/expensive up keep. But with a little community development/using readily available products it might be a thing.
I made one. Just used a 12v pump and a couple of filters - totally cheap. There are a lot of YouTube videos showing how to diy it.
 
I made one. Just used a 12v pump and a couple of filters - totally cheap. There are a lot of YouTube videos showing how to diy it.
Thanks! I'm on it. When i saw "efficient" and "heating" on this thread I projected heating water efficientlyo_O.
 
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