my furnace back up

David in nh

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this is my oil furnace battery back up , plus one outlet , it is a aimes hard wired 12v 1200 watt inverter with built in transfer switch
, a home built battery 200ah lifepo4 with a overkill bms , not having to add other meters to see what was going made install much cleaner , the blue tooth to my tablet works great .
battery has circuit breaker in box and is attached to inverte2 with a 175 amp anderson connector and #2 wire
this is a small system only ment to run the furnace untill i decide to start the generator , larger transfer switch on left is for that , the 12v is in line after main transfer switch , so 12v goes off gen goes on

as for charging thats a project for later , for now i use a small noco charger that does lifep4 only took me watching 100 for Will's videos to try something

below is a shot of the furnace running at 229 ways but it does go up to 497 when all zones are working , in this pic it was just heating my hot water after being off for a day , when the furnace is doing nothing it pull 23 watts

house is very well insulated and does not cool down fast , but if the power goes out over night or i am away i hoping this will get few more hours of heat i am hoping for a least 8 hrs but and will test out on a cold day at some point maybe i will ad a solar panel or two

now be kind if you see something wrong :)
20200906_180052.jpg
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Supervstech

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Does this setup successfully power the burner and blower motors?
 

David in nh

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Does this setup successfully power the burner and blower motors?
this is a oil fired forced hot water system (baseboards)so there are no blowers . and yes if you look at the screen shot screen shot of the bms
in a very well insulated 20 year olds home 1200 sq ft house
turned the heat to 80 to make it come on and heat domestic hot water i got 497 watts furnace had been of for 24 hrs surge rating on inverter is 2400 with run of 1200
 

David in nh

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Looks like about 4.5 hours of backup power at full blast.
yes thats what i got time wise at full tilt , but since this is a oil fired forced hot water system (baseboards) even at below zero temps Fahrenheit that are fairly rare here it never runs at full tilt more then 50 percent of the time , the one circulate pump on the heat loop takes very little power

At 30 Fahrenheit were ice storms take place and that's when i loose power furnace may only run on full 30 percent
 

Supervstech

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this is a oil fired forced hot water system (baseboards)so there are no blowers . and yes if you look at the screen shot screen shot of the bms
in a very well insulated 20 year olds home 1200 sq ft house
turned the heat to 80 to make it come on and heat domestic hot water i got 497 watts furnace had been of for 24 hrs surge rating on inverter is 2400 with run of 1200
Ahh.
Boiler, that makes sense. Air movers are tricky to power up the loads... a boiler would be a lower demand system.
 

David in nh

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here are some answers to question from people i got that are not on this board

Q what did it cost ?

A about 1000 dollars for inverter bms battery wire dc breaker and wire

Q you could have done it cheaper with a ebay inverter and a deep cell battery

A yes on inverter , but then i would not have a ul approved inverter with a automatic transfer switch
A batteries for the same power i would need at least 2 sealed batteries then i would have wanted all the information the bms give me so there would have been more wiring and parts this keeps everything simple


Q seems like a waste of time and money to me

A its a hobby i enjoyed doing it , cheaper then sitting at a bar
A think of this way , power goes out at 9 pm i get up in the morning house is warm . start the generator to run the well pump , put a small added charge to battery take a shower because the furnace does the hot water it is hot already , as i get ready for work the fridge / freezer does it thing , i then shut off gen and before i leave i turn the heat down to 55. to give my battery a few hours off before they need to do anything and so the fridge warms up less
i then go to work on time , and buy the time i come home most likely the power will be on.

well at least that's my story and i am sticking to that lol
 
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David in nh

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Some more testing .now that I have the furnace all set I thought I would test out the fridge.
I have manually plug that in to the inverter but was surprised to see it pulling 138 wats when running , I expected more than that .
It looks like Could run the furnace and the fridge at the same time but with 200ah battery and no Solar I do not plan to do that , but if the power goes out during a non heating time , could stretch the run time on the fridge
 

David in nh

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Update
well we have not lost power in the last few storms , so it was time to a overnight test

#1 outside temp 20F inside 68f

#2 domestic hot water done trough furnace, still on but never used ,like if the power was out because i would have no power to well

#3 basement heat zone is has thermostat all the way down as always unless i am down there working

# 4 overkill bms reading 199.2 ah

flipped the breaker off at 6:30 pm

next morning turned power back on at 6:30 am

bms now reading 103 amp hours

one very happy camper
:)
 

Hedges

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Since you have plenty of high-grade thermal energy available, how about a Sterling or other heat engine running a generator? Can you come up with a safe, low maintenance generator to keep battery charged and produce 100% of the heater's electric needs?
 

schmism

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I always thought if you had a wood burning stove that useing some TEG's rigged up to some PC water cooling parts with the cold side ran outside through the wall to a radiator would net you a fairly constant source of several hundred w depending on how many you used.


however I the brain threw all that section of heat transfer from college... something about 600F on one side...and how many btu can i transfer across 3800mm based on a given cold plate...20f deg liquid..what flow rates are needed..what does that result in a temp drop across the TEG
 
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David in nh

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Since you have plenty of high-grade thermal energy available, how about a Sterling or other heat engine running a generator? Can you come up with a safe, low maintenance generator to keep battery charged and produce 100% of the heater's electric needs?
not sure why or how i would want to do that , my electricity bill runs 35 to 40 dollars in the winter for my whole house
this is just for the few times a year i lose power during a storm

as for high grade thermal , this is the granite state so in my case i would have to have bore holes drilled , but again at the price of oil even when it was twice as high , thinking not a good choice for me

now i am adding a small solar panel at some point to keep the battery topped off
 

David in nh

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I always thought if you had a wood burning stove that useing some TEG's rigged up to some PC water cooling parts with the cold side ran outside through the wall to a radiator would net you a fairly constant source of several hundred w depending on how many you used.

i do not have a wood stove , not a fan of them , sure if lived out in the woods far from everything , but i live on a two acre lot in a housing development , cool idea but i think i would be better off with some solar panes
 

Hedges

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not sure why or how i would want to do that , my electricity bill runs 35 to 40 dollars in the winter for my whole house
this is just for the few times a year i lose power during a storm

as for high grade thermal , this is the granite state so in my case i would have to have bore holes drilled , but again at the price of oil even when it was twice as high , thinking not a good choice for me

now i am adding a small solar panel at some point to keep the battery topped off
I only meant to keep the furnace operating during power failures without sunshine.
Often it is during stormy weather when you want heat and the power is out.

By high-grade thermal energy, I meant the temperature of the furnace is sufficient to run a steam engine, not like flat-plate solar collectors.
Efficiency isn't important. Something like a sealed Sterling engine would produce mechanical power to run a generator, and the waste heat ends up in the room anyway.

Thermo-electric appears attractive at first, but cost per watt is excessive.

If you can live through power failures, bundle up if necessary, then non-PV solutions aren't practical.
 

David in nh

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I always thought if you had a wood burning stove that useing some TEG's rigged up to some PC water cooling parts with the cold side ran outside through the wall to a radiator would net you a fairly constant source of several hundred w depending on how many you used.


however I the brain threw all that section of heat transfer from college... something about 600F on one side...and how many btu can i transfer across 3800mm based on a given cold plate...20f deg liquid..what flow rates are needed..what does that result in a temp drop across the TEG
Since you have plenty of high-grade thermal energy available, how about a Sterling or other heat engine running a generator? Can you come up with a safe, low maintenance generator to keep battery charged and produce 100% of the heater's electric needs?

okay guys now you got me thinking , and i admit i really no idea what you were talking about , but looking at the amazon link you gave me above
i gotta ask has one any tried these out ? would they put out any power at the temp difference of my furnace and my basement say 60 degrees and 160 ? not home not sure of temp of water the runs though 180 ?
https://www.ebay.com/itm/12V-15A-He...793215?hash=item3b079ce4ff:g:-qEAAOSwbdpWYUAK

i see them as low 12 bucks

would they really produce any power when clamped on to the copper pipes coming out of the furnace ?

ais there any data for doing this like a 12v 15a Thermoelectric will produce 1v at .5 amp or if they are pruduce the volts is always 12v and the amp very s according to temp difference ? at a 100 temp difference

now if they could produce say 1 amp of power at 12 volts and use two to get 24 volt and run it though one those cheap lifepo4 chargers
that may be fun project 2 of them and 24 dollars and a 15 dollar charger . it may be a fun project to try
 

Hedges

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Single one, not much power.
Somebody had a listing for 30W unit with self-powered fan. But it said it works at 380 degrees C, max temperature 450 C.
Usually TEC are assembled with solder, melts at too low a temperature. For TEG application with 450 C max, there is a narrow window to avoid wrecking it.

TEG are used in some expensive industrial applications, like oil fields with gas always flaring off, for low-maintenance power.

One guy got an oil fired heater with TEG that seems to work.

 

dougbert

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here are some answers to question from people i got that are not on this board

Q seems like a waste of time and money to me

A its a hobby i enjoyed doing it , cheaper then sitting at a bar
A think of this way , power goes out at 9 pm i get up in the morning house is warm . start the generator to run the well pump , put a small added charge to battery take a shower because the furnace does the hot water it is hot already , as i get ready for work the fridge / freezer does it thing , i then shut off gen and before i leave i turn the heat down to 55. to give my battery a few hours off before they need to do anything and so the fridge warms up less
i then go to work on time , and buy the time i come home most likely the power will be on.

well at least that's my story and i am sticking to that lol

beautiful answer to that kind of question
people without vision/understanding it all seems useless. They are also the ones who buy $75,000 trucks and think all is well (THAT is useless to me - each of us have our choices)

a hobby shuts down most people who ask that question
 

Hedges

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30W to 50W hardly qualifies as an "appliance".
Good for either a small continuous load, or stored up in a battery for occasional use.
But if operating 24 hours a day, it does produce as much as a 150W to 250W PV panel.
 

David in nh

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Update
well it,s 55 out i thinking winter storm season is pretty much over here

i never lost power , outages came with in a few miles of me , but i never even flickered enough to have to reset the oven clock

oh well maybe we get power outages next winter i guess i will just wait :)
 
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