How to power this APPLIANCE - do you know how ?

[Michael Luton]

I'll check out the nansolate. Over the cement block a reflective coating might actually be more meaningful than insulation. Here at 15 cents a kw/h I have a little more incentive than you electrically, but I do heat with natural gas for economic reasons. Understand the freedom thing, however unfortunately in my income bracket lower cost does equate to a freedom factor.

[Aaron Murakami]

Thanks for trying Aaron. My problem is my house is a 1915 cement block house with a super hard concrete stucco that is almost impossible to penetrate even with a masonry drill bit or I could add external insulation. Internally there are 3/4 inch thick nailers nailed into the mortar joints and then covered with plaster and lath. Basically it would turn out to be so expensive to insulated that I would be looking at a 40 year payback and in my area would not add to the resale value of the house as I'm already topped out for my part of town.

I have an idea that I'm considering that I will not repeat here as while I am comfortable with it, it will not pass any building codes and I have to figure how to do it without getting caught by the city inspector.

Check out NANSULATE coatings. It's both radiant reflective but also has insulation value.

I've used nanosphere ceramic coatings before, they're only radiant reflective since heat doesn't go through a vacuum in the nanospheres.

The Nansulate is a good product and they have applications for inside walls, outside walls, roofs, boiler pipes, etc. you name it.

It's paint on so can be added to anything. You'd have to do the numbers to see if it is worth it to you.

For me, the retrofoam was a bit spendy, we only pay about 8 cents per kw/h here so payback is a long time. It won't have as much r value as the foam, etc. but is worth looking into. For me, I'm more interested in freedom than roi, which I think should not always the primary objective - just how I see it.

[Michael Luton]

Thanks for trying Aaron. My problem is my house is a 1915 cement block house with a super hard concrete stucco that is almost impossible to penetrate even with a masonry drill bit or I could add external insulation. Internally there are 3/4 inch thick nailers nailed into the mortar joints and then covered with plaster and lath. Basically it would turn out to be so expensive to insulated that I would be looking at a 40 year payback and in my area would not add to the resale value of the house as I'm already topped out for my part of town.

I have an idea that I'm considering that I will not repeat here as while I am comfortable with it, it will not pass any building codes and I have to figure how to do it without getting caught by the city inspector.

[Aaron Murakami]

If it is any consolation this heating thing is an issue I'm fighting too. I live in a home that has no insulation and cant be insulated reasonably due to the construction and the solar option is not good either in my situation. So I'm constantly looking for alternatives to help in my situation.

Fall of last year, I had expanding foam put into all my walls from the outside. Was one of the biggest differences I've made to my home. It can be done to almost any home that is not easy to get into the walls. They remove some siding and drilled holes into the boards behind then injected the mixture. They put everything back like it was - I just need to get the touch up nail holes painted. Early 60's home and was lucky if there was some 1" thick insulation in the wall, which was sagging so lots of space for air to move so essentially, the home had zero insulation.

Here is the product I had installed: http://www.retrofoam.com/foam-insulation-installation/

They can get it into areas where you might think they can't. One part of a brick facade, they drilled small holes in the grout between the bricks so almost no place is off limits.

That gets to one of the main points in what we've always believed is if you hold on to the heat you make and keep out the heat you don't want, you can drastically cut the number of solar panels needed. Average US home loses half of the energy is uses and heating/cooling is about 50% of the average consumption. It is less expensive to put money into reducing loses than it is to purchase a solar system where 1/2 of what is produced is wasted anyway. My 2 cents.

[Michael Luton]

If it is any consolation this heating thing is an issue I'm fighting too. I live in a home that has no insulation and cant be insulated reasonably due to the construction and the solar option is not good either in my situation. So I'm constantly looking for alternatives to help in my situation.

[Michael Luton]

I was just trying to keep things simple by converting everything to watts so we were only dealing with one unit of measure. I didn't mean to confuse you, but everything does come back to the amount of power stored, delivered, and the rate which the power is used at. This is why your heater is rated in watts, just like light bulbs are rated in watts.

First thing:
You need to understand that watts is power, amps is current, and voltage is potential. One of the ways of figuring power (or watts) is amps times volts, therefore 12 v X 100a = 1200w for one of your batteries. 4 batteries times 1200w = 4800w.

Second thing is:
Batteries connected in parallel the voltage is the same and the current is additive so 2 of your batteries in parallel will be 12v and 200a which is 12v X 200a = 2400w
Batteries in series the current remains the same and the voltage is additive so 2 of your batteries in series would be 24v X 100a = 2400w
If 1 set of your batteries in parallel is 12v and 200a then 2 sets in series the current would stay the same and the voltage additive so you would have 24v X 200a = 4800w

You can optimize for voltage by putting 4 batteries in series to have 48v and 100a. 48 X 100 = 4800w
You can optimize for current by putting 4 batteries in parallel giving 12v and 400a. 12 X 400 = 4800w
No matter what you do you will always end up with the same amount of power from your 4 batteries.

Third thing is:
I have to agree with John Koorn that this will just end up costing you a lot more money to get working and even then not give you satisfactory results. You would have to add more solar panels, more batteries, another charge controller, and still be out of luck on cloudy days. I wouldn't give up on your solar system, but instead rethink it. John made a good suggestion with the evacuated tube system. You could then use your solar system to run a pump for the fluid, have some lights (LED preferably) and maybe power a small radio for some tunes. Then get a back-up propane heater or a wood/pellet stove for some cloudy days.

Again even though I'm not telling you what you want; I am trying to help. Honestly.

Michael

[John_Koorn]

meanstack, I don't want to sound mean but you should've done your research before laying out that amount of money. The fact that you can't work out how Michael explained how he got 4800W tells me you don't have a lot of understanding on renewable energy solutions.

As has already been well stated, running your 1500W ceramic heater from batteries charged by solar panels is never going to be effective. You'd be better off scrounging wood for a fireplace to heat your home.

Aaron has already told you that a much more efficient way to produce heat from solar is evacuated tubes. I ran a solar evacuated tube hydronic heating system that heated a 500 square meter home. It also produced all of our hot water needs from just 30 tubes. The system was backed up by a natural gas furnace, but over the course of 2 years it had paid for itself and I hardly spent any money on gas - only when it rained for a few days in a row.

Save your solar panels and batteries for low wattage lighting and small appliances. I don't know anyone in the world that would be using your style of setup for heating, it's just not practical.

John K.

[i/o]

Hello friend. You are right about the solar cell industry over selling itself. If you want to remain with a solar solution: 1) take your solar panels back to the store and get your money back. Same with batteries and electric heater.
2) get some nice aluminum sheets, install on total floor area interior, extend to exterior patios they must all be made into a monolithic aluminum floor structure. (aluminum foil would work but thicker is better)
3) install ceramic tile (like on the space shuttles -only find cheaper tiles that store heat) on top of aluminum sheets interior. Paint exterior part of aluminum sheeting black.
Sun's heat will be absorbed into blackened aluminum. Properties of aluminum will allow for heat to be evenly distributed through conduction into interior (like electronic heat sink into the interior floor). The tile stores and slowly releases the heat from the aluminum sheeting underneath it. If you want to adjust this storage and release, shade the blackened aluminum part until cooler or install water reservoir in pipes beneathe the aluminum sheeting.
Hope this solution helps.

[meanstack]

(This is pretty much the same as what Aaron said with different wording. I'm not trying to step on Aaron's toes, but I had this already typed up last night and my internet went down before I could send it.)

I feel for you. You got in without a lot of knowledge and it is frustrating you with the results.

Yes this is a simple device you are trying to run as far as the electrical circuitry for a heater is concerned. However it is a monster when it comes to power consumption. Remember 1500w is the same amount of power that is needed to run 25 60w incandescent light bulbs. This means you have to shift your thinking to dealing with a device using a large amount of power. This is also why it is first recommended you invest in energy conservation measures (LED lighting, Insulation, sealing cracks, etc.) before investing in solar power in general applications.

Lets start with 6 300w panels will give you 1800w rated value. That is under ideal lab conditions. In real life you can probably expect 1500w on a good sunny day. This means if you have your panels angled properly you should get 1 hour of 1500w use for 1 hour of good sun. This means I can't see getting 18 hours use at 1500w from these panels no matter what you do.

Now lets look at the batteries. Rather than trying to lay too much of this out in volts and amps I will mostly try to keep things in watts to keep the math simpler and the explanation shorter. First your 4 batteries will give you 400 AH at 12 volts or 200 AH at 24 volts, it is 4800w either way. Batteries are rated at C rate which is how long you discharge for in hours to get the AH stated. I did not see a C rating listed on your batteries (to be honest it was a quick look and may have missed it), but given the example uses and that it is an AGM battery I would probably go with a C20 rating which means 240w per hour for 20 hours. If you did go with a heavy duty deep cycle use it would be C10 or 480w at 10 hours continuous draw on the batteries. Trying to draw 1500w would be about a C3 rate which means you are probably trying to draw power out faster than the battery can supply it. This will damage the battery if done on a continuing basis.

One last thing that concerns me and you did not mention is your DC wiring. I hope all your DC wiring is 6 AWG like was recommended with the charge controller. If not, at the amperage's that you are dealing with the cables can over heat and possibly start a fire and that scares me. None of this is worth what can happen with a fire.

I don't think I gave you the answers you were looking for, but I hope this helps with your understanding of what you are dealing with.

thank you friend

QUES: where do you get the 4800watt figure from that threw me

QUES: batteries are wired in parallel doesn't that double the amperage capacity? That's why I went parallel... im thinkin you got that backwards everything is geared for most amps

QUES: batteries are either wired serial, or wired parallel or wired parallellANDSerial... can I do parallelANDparallell for 400ah?
https://www.gwstore.co.za/correct-ba...energy-system/
i guess im wondering how to get max amps out of the four batteries

LASTQUES: so how many batteries would I need and do you have a link to the kind you would use?

everything beyond c40 charge controller is thick 2-4 awg with breaker fuses on pos leads in case of surge thanks

- cheers

[Michael Luton]

(This is pretty much the same as what Aaron said with different wording. I'm not trying to step on Aaron's toes, but I had this already typed up last night and my internet went down before I could send it.)

I feel for you. You got in without a lot of knowledge and it is frustrating you with the results.

Yes this is a simple device you are trying to run as far as the electrical circuitry for a heater is concerned. However it is a monster when it comes to power consumption. Remember 1500w is the same amount of power that is needed to run 25 60w incandescent light bulbs. This means you have to shift your thinking to dealing with a device using a large amount of power. This is also why it is first recommended you invest in energy conservation measures (LED lighting, Insulation, sealing cracks, etc.) before investing in solar power in general applications.

Lets start with 6 300w panels will give you 1800w rated value. That is under ideal lab conditions. In real life you can probably expect 1500w on a good sunny day. This means if you have your panels angled properly you should get 1 hour of 1500w use for 1 hour of good sun. This means I can't see getting 18 hours use at 1500w from these panels no matter what you do.

Now lets look at the batteries. Rather than trying to lay too much of this out in volts and amps I will mostly try to keep things in watts to keep the math simpler and the explanation shorter. First your 4 batteries will give you 400 AH at 12 volts or 200 AH at 24 volts, it is 4800w either way. Batteries are rated at C rate which is how long you discharge for in hours to get the AH stated. I did not see a C rating listed on your batteries (to be honest it was a quick look and may have missed it), but given the example uses and that it is an AGM battery I would probably go with a C20 rating which means 240w per hour for 20 hours. If you did go with a heavy duty deep cycle use it would be C10 or 480w at 10 hours continuous draw on the batteries. Trying to draw 1500w would be about a C3 rate which means you are probably trying to draw power out faster than the battery can supply it. This will damage the battery if done on a continuing basis.

One last thing that concerns me and you did not mention is your DC wiring. I hope all your DC wiring is 6 AWG like was recommended with the charge controller. If not, at the amperage's that you are dealing with the cables can over heat and possibly start a fire and that scares me. None of this is worth what can happen with a fire.

I don't think I gave you the answers you were looking for, but I hope this helps with your understanding of what you are dealing with.

[Faraday88]

Those are very small batteries for something like this.

For example 1500 watt heater at full blast - 1500 watts divided by 12 volts = 125 amps

If you want to be at the 20 hour discharge rating, 125 amps x 20 hours = 2500 amp hour battery.

If you take the amp hour rating 100 amp hours - you divide by that 20 hours, which equals 5 amps - a 100 amp hour battery can provide 5 amps for 20 hours.

There is a 5 hour rating, which means you can draw way more for 5 hours, but you only get about 80% of the capacity. So that means at 100 amp hour, a 5 hour discharge, you'll get about 80 amp hours.

80 amp hours divided by 5 hours = 16 amps x 12 volts = 192 watts - so a single 100 amp hour battery can at the max safely power 200 (192) watts for 5 hours.

1500 watt heater - you need about 8 of those batteries (in parallel) at full charge to power that heater at full charge and at max for 5 hours until the batteries are dead at about 10.5 volts. That is if you're using a pretty high efficiency inverter for a 12v bank and the inverter is rated at a few thousand volts so you're not maxing it out.

How much solar do you need? Well, 3000 volts is double the max load so under full sun 1/2 of that will power your heater while the sun is out while the panels are also giving 1500 watts to the batteries for the same period of time. When sun goes down, you draw that from the batteries for the same hours minus the loss but for simple numbers...

Are you understanding some of what I'm saying? RS or Tom or someone else can probably give a much better and more accurate answer as they have a lot more solar experience than I do, but the battery calculations above are fairly standard.

@ Aaron Well elaborated explanation...just to add a few more things i know of.. its about some De-rating factors like the Inverter efficiency to be considered for the conversion in the calculation..
Rgds,
Faraday88.

[Aaron Murakami]

Those are very small batteries for something like this.

For example 1500 watt heater at full blast - 1500 watts divided by 12 volts = 125 amps

If you want to be at the 20 hour discharge rating, 125 amps x 20 hours = 2500 amp hour battery.

If you take the amp hour rating 100 amp hours - you divide by that 20 hours, which equals 5 amps - a 100 amp hour battery can provide 5 amps for 20 hours.

There is a 5 hour rating, which means you can draw way more for 5 hours, but you only get about 80% of the capacity. So that means at 100 amp hour, a 5 hour discharge, you'll get about 80 amp hours.

80 amp hours divided by 5 hours = 16 amps x 12 volts = 192 watts - so a single 100 amp hour battery can at the max safely power 200 (192) watts for 5 hours.

1500 watt heater - you need about 8 of those batteries (in parallel) at full charge to power that heater at full charge and at max for 5 hours until the batteries are dead at about 10.5 volts. That is if you're using a pretty high efficiency inverter for a 12v bank and the inverter is rated at a few thousand volts so you're not maxing it out.

How much solar do you need? Well, 3000 volts is double the max load so under full sun 1/2 of that will power your heater while the sun is out while the panels are also giving 1500 watts to the batteries for the same period of time. When sun goes down, you draw that from the batteries for the same hours minus the loss but for simple numbers...

Are you understanding some of what I'm saying? RS or Tom or someone else can probably give a much better and more accurate answer as they have a lot more solar experience than I do, but the battery calculations above are fairly standard.

[meanstack]

for starters I think I have a battery bank capacity issue

I dont know what the formula is to calculate capacity for battery bank to sustain this 1500watt space heater

im thinking I need at least 1800 amp hours of battery bank capacity

my 4 batteries only provide 400ah (correct me if im wrong) given the 4 battery setup configuration

so I guess I would need at least 18 batteries to get 1800 ah capacity?

and then comes the load problem

How do I sustain a charge to this battery bank so it will run hour to hour hopefully for at least 18 hours of day

[meanstack]

thank you friend

here is my panels

monocrystaline
6 in total divided to two arrays 3 per array
https://www.ebay.com/itm/2PCS-S-ENER...S/263645232024

here is my charge controller one per array
https://www.altestore.com/store/puer...032/#PR-XANC40

here are my batteries currently 4 total (2 wired parallel then combined serial)
https://www.ebay.com/itm/New-UB12100...e/171452211893


here is my inverter
https://www.altestore.com/store/inve...-switch-p2172/

specs are on the site i tried to copy/paste but it garbled

this setup is precise everything is metrically sound... it wont power jack maybe a fridge or well pump or some lightbulbs... I NEED HEAT...

I feel totally raked by solar I cannot even run that simple little space heater

so this will run the space heater... for five minutes though?
the load on battery bank nose dives

I thought a bedini 10 pole spoked wheel generator could do what the panels cant

[Aaron Murakami]

thank you for trying... not the answer Im seeking
i spent $4500 on solar and its turned to be a scam
just thinking about water and plumbing and installation is an outrageous thought for solar water

I just want to plug this simple appliance into a sustainable power source...
im totally amazed humanity has come this far and we still cant do it

Almost all solar is intriniscally a scam.

https://fas.org/sgp/othergov/invention/pscrl.pdf

Shows: Item 8. Solar photovoltaic generators (AM C)-if > 20% efficient (NASA) (AF)

Going back to the early 70's, the Federal govt already indicated that if solar is over 20% efficient, it could potentially be shut down under the patent secrecy acts. Today, the efficiency is still pretty much the same.

I don't know what panels you have, but crystalline are more efficient than amorphous. But that is in lab conditions. Compared to amorphous panels, it takes less square foot for the same watts. But that is a scam - because crystalline works on infrared. If clouds come, you drastically cut infrared. Amorphous being "less efficient" - but they operate on blue/green so if clouds come, you still have plenty of visible light so overall, the lower efficiency amorphous panels wind up giving you more electricity than high efficient crystalline panels.

https://powerspotsolar.files.wordpre...arsecrets.pdfj - that is our book that explains this in detail.

With what you already have, there may be way to use it in a more effective way.

Post all of your exact details for your system and let's look at it.