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Discussion Starter #1 (Edited)
Ran across this story and thought I would share.

I know there are a few engineers here and students. Read the 2 page article and see if you can spot all the fairy-tales. This article comes across as science. While there is some science to it, most of it is Poppy Cock with respect to hydrogen.

Read it and see what you spot. Then I will comment and tell you some things I caught like containment vessels, weight, volume, and pressure.
 

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I didn't even make it to the second page before I went "wait, what?" How does he use electricity to make hydrogen, and then have water as a by-product?

WTF, how did he get $400,000 in grants/subsidies to build this thing? Glad I don't live in NJ, that's some #$^%&%^ waste of taxes right there. All so that he doesn't have to pay any bills to utilities, which are often partially government run.

WTH kind of garage does this guy have that he can fit 56 solar panels on it? Why would you pay 400,000 to take the Tahjmahal off the grid??

How is he pumping Freon around? Isn't that stuff outlawed now?

How did he hit granite at 7.8ft down?

!!! 3 million dollars for a Mercury SABLE?? I want what Ford is smoking!!

Where is gas at $4 a gallon right now? Maybe HAWAII, sure not in New Jersey!!

Ok that's all the interesting things I gleaned from it.
 

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Discussion Starter #3
I didn't even make it to the second page before I went "wait, what?" How does he use electricity to make hydrogen, and then have water as a by-product?
I think maybe you might have misread that part. He claims to have a hydrogen fuel cell in his home to make electricity during the winter with the hydrogen he stores up in the summer. That is where I went huh? How can he contain enough hydrogen in low pressure LPG tanks that leak around 2% per day, plus battle Hydrogen Embrittlement. 19,000/ft3 of hydrogen is not very much energy, at least not a winters worth of electricity. Maybe enough for one tank full in his Mercury Sable compressed to 10,000 PSI. Hum I wonder where he gets the energy to compress it to 10,000 PSI?


WTF, how did he get $400,000 in grants/subsidies to build this thing? Glad I don't live in NJ, that's some #$^%&%^ waste of taxes right there. All so that he doesn't have to pay any bills to utilities, which are often partially government run.
That part really frost my pumpkin as with any government subsidy for solar PV. My firm recently built a 500 KW system for Walmart in Plano TX that generates on average about 3 Mwh per day ($400 at current TX prices). Total cost to Walmart was just under $.5 M after all the subsidies tax and utility rate payers pitched in $5 M. The system will pay off in roughly in 4 years at which point that $400 per day savings goes right to Walmarts profit line at our expense. :mad:

WTH kind of garage does this guy have that he can fit 56 solar panels on it? Why would you pay 400,000 to take the Tahjmahal off the grid??
Yeah that is the big lie when he says he will never pay a another dime for electricity. Off-Grid battery systems will cost you a minimum of 10 times more for electricity than buying from a electric company. He failed to mention all those batteries have to be replaced every 5 years or so at a cost of around $100K or more. :eek:
 

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I think maybe you might have misread that part. He claims to have a hydrogen fuel cell in his home to make electricity during the winter with the hydrogen he stores up in the summer. That is where I went huh? How can he contain enough hydrogen in low pressure LPG tanks that leak around 2% per day, plus battle Hydrogen Embrittlement. 19,000/ft3 of hydrogen is not very much energy, at least not a winters worth of electricity. Maybe enough for one tank full in his Mercury Sable compressed to 10,000 PSI. Hum I wonder where he gets the energy to compress it to 10,000 PSI?
I did some calculations and it doesn't seem off to me. I estimated the energy density to be 0.1 MJ/L at low pressure using a graph on page 13 of this document:
http://www1.eere.energy.gov/hydrogenandfuelcells/pdfs/bulk_hydrogen_stor_pres_sandia.pdf

I could be wrong, but I came up with 15,000 kWh of energy stored in the hydrogen tanks.

Leakage shouldn't be a problem at low pressure with steel tanks.

The only concern about hydrogen embrittlement is to structural integrity.


...

Yeah that is the big lie when he says he will never pay a another dime for electricity. Off-Grid battery systems will cost you a minimum of 10 times more for electricity than buying from a electric company. He failed to mention all those batteries have to be replaced every 5 years or so at a cost of around $100K or more. :eek:
The above statements are very similar to arguments against battery-electric vehicles.

I believe the statement was more to the effect of not having to pay the utility company. The article seems quite open that this is a very expensive setup.

I don't see the problem, except if one has a political problem with the state's role. It sounds to me like he's got a huge PV system, a high performance (HFC)EV, and whatever it takes to get things like this done.

Maybe the issue is: "The debate boils down to whether batteries or hydrogen are a better way to store and deliver electrical energy."

Thanks,
Kurt
 

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Discussion Starter #5
I did some calculations and it doesn't seem off to me. I estimated the energy density to be 0.1 MJ/L at low pressure using a graph on page 13 of this document:
http://www1.eere.energy.gov/hydrogenandfuelcells/pdfs/bulk_hydrogen_stor_pres_sandia.pdf

I could be wrong, but I came up with 15,000 kWh of energy stored in the hydrogen tanks.
Hey Kurt thanks for the reply. For now I will give that the benefit of a doubt, and for argument sake say OK.

So where does the 15,000 Kwh come from? Well as you read he claim he has 56 solar panels, and in June they generate 90 Kwh per day. Ok taking that at face value June in Central NJ receives at best with 0% latitude fixed orientation 6 Sun Hour Day. Completely ignoring best case efficiency of an off-grid battery solar system of 66% would require 90 Kwh / 6 h = 15 Kw solar panel array. 15 Kw / 56 panels = 270 watts per panel. Largest panel wattage I know of are around 240 to 250. If you look at the slide show you can see the panels. From the physical size I would estimate 140 watt panels.

But this is where it gets off. Factor in 66% efficiency for a FLA battery system and the panels need to generate 90 Kwh / .66 = 136 Kwh per day, and that would take a panel wattage of 136 Kwh / 6 h = 22.6 Kw at 400 watts per panel. There is no such thing as a 400 watt solar panel that I know of.

Next thing that really tips me off is he claims he only uses 10 Kwh per day with all the luxury toys one would expect from such a monster sized home. That strikes me as very odd. How can this guy only use 1/3 of what the average home uses? Looks like he has around 4000/ft2 home. I live in an 10 inch ICF 2500/ft2 and I use almost 3 times that much energy. My home is custom designed with geo thermal heat pumps, sun light, sun tubes, ect and I cannot do that good. I just do not see it. But for argument sake lets say he is a hermit and never uses his appliances and toys. That leaves him 80 Kwh per day for a period of a few months to make hydrogen.

How efficient is is electrolysis hydrogen generator? 75%, 50% ? What percentage does he loose to compressing it?. So assuming his electrolysis machine is 100% efficient and it takes no energy to compress the gas at 80 Kwh per day production it take 15,000 Kwh / 80 Kwh/day 188 days to fill the tanks. Well he doesn't have 188 6 Sun Hour Days to work with. He only gets 6 Sun Hour days for a few short weeks in June and early July. On average through the year at best he gets 3.9 Sun Hours with a low of 2.5 hours in December and January. Bu tif he has a 10 Kwh solar panel array which is likely, and only uses 10 Kwh per day, he has no need to generate hydrogen as he is not using what he produces anyway. Strange!

There is just too many things that don't add up in my mind. I do believe he built the system. He has the pictures to prove it. I also believe he used your money for his own profit. :cool:
 

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... see if you can spot all the fairy-tales. This article comes across as science. While there is some science to it, most of it is Poppy Cock with respect to hydrogen.

Read it and see what you spot. Then I will comment and tell you some things I caught like containment vessels, weight, volume, and pressure.
The above, especially the part I made bold, is what I questioned initially. As to the science- there's not enough information in the article, which is probably the nature of reporting. Without enough information there are a lot of assumptions. At what pressure is the hydrogen stored in the tanks? What is the storage system in car? I made an estimation of the energy stored in the tanks to see if it seemed anywhere near reasonable. I wouldn't bet much on it, but it seems reasonable. That amount of hydrogen looks to be more than one fill-up of the car. The bigger question is why does this article bother you?

Hey Kurt thanks for the reply. For now I will give that the benefit of a doubt, and for argument sake say OK.

So where does the 15,000 Kwh come from? Well as you read he claim he has 56 solar panels, and in June they generate 90 Kwh per day. Ok taking that at face value June in Central NJ receives at best with 0% latitude fixed orientation 6 Sun Hour Day. Completely ignoring best case efficiency of an off-grid battery solar system of 66% would require 90 Kwh / 6 h = 15 Kw solar panel array. 15 Kw / 56 panels = 270 watts per panel. Largest panel wattage I know of are around 240 to 250. If you look at the slide show you can see the panels. From the physical size I would estimate 140 watt panels.

But this is where it gets off. Factor in 66% efficiency for a FLA battery system and the panels need to generate 90 Kwh / .66 = 136 Kwh per day, and that would take a panel wattage of 136 Kwh / 6 h = 22.6 Kw at 400 watts per panel. There is no such thing as a 400 watt solar panel that I know of.
Since the 15,000 is a crude estimate I think we can't base much off of it. But, your estimate of 270 W required and 140 W panels doesn't seem like a huge difference. And, maybe there was leftover hydrogen for more than one year. Again, not enough information and probably a lot of assumptions.

Sunking said:
Next thing that really tips me off is he claims he only uses 10 Kwh per day with all the luxury toys one would expect from such a monster sized home. That strikes me as very odd. How can this guy only use 1/3 of what the average home uses? Looks like he has around 4000/ft2 home. I live in an 10 inch ICF 2500/ft2 and I use almost 3 times that much energy. My home is custom designed with geo thermal heat pumps, sun light, sun tubes, ect and I cannot do that good. I just do not see it. But for argument sake lets say he is a hermit and never uses his appliances and toys. That leaves him 80 Kwh per day for a period of a few months to make hydrogen.
It seems to me he's not wasting a lot of energy, even though his house is larger than average.

Sunking said:
How efficient is is electrolysis hydrogen generator? 75%, 50% ? What percentage does he loose to compressing it?. So assuming his electrolysis machine is 100% efficient and it takes no energy to compress the gas at 80 Kwh per day production it take 15,000 Kwh / 80 Kwh/day 188 days to fill the tanks. Well he doesn't have 188 6 Sun Hour Days to work with. He only gets 6 Sun Hour days for a few short weeks in June and early July. On average through the year at best he gets 3.9 Sun Hours with a low of 2.5 hours in December and January. Bu tif he has a 10 Kwh solar panel array which is likely, and only uses 10 Kwh per day, he has no need to generate hydrogen as he is not using what he produces anyway. Strange!
My reply of "Not enough information" seems to apply to the estimations.

The bold part is interesting. The hydrogen is an energy storage (or I've heard it called "carrier") system for the PV system. So, what's the issue with generating hydrogen to take full advantage of a PV system? My thought is that maybe the battery pack is too big and the hydrogen storage could take more of the energy storage role. What is the life cycle and overall efficiency of the battery system versus the hydrogen system? How would a fuel cell rank in there?

And, one of the points of using hydrogen on a larger scale seems to be to take better advantage of PV and other solar and renewable energies. I don't know how other storage compares. The example that comes to my mind is an elevated water tank system.

Sunking said:
There is just too many things that don't add up in my mind. I do believe he built the system. He has the pictures to prove it. I also believe he used your money for his own profit. :cool:
I'm guessing that last part is what chaps your hide the most. How much do we know about the public utility grant money?


Anyway, I find the article and your response to it interesting. I have had pipe dreams of doing something similar to the hydrogen house but on a smaller scale. One of the reasons for doing it would be to try to determine the realities of hydrogen by experience.

Thanks,
Kurt
 

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I agree the thing is there just isn't enough information. I find the 90kwhr/ day from the panels to be a bit aggressive, espeacialy for jersey... I usualy estimate 1kwhr/day/m2 for system. Most panels are 1 m2, so he shoudl be getting around 56kwhr/day... 90 just seems too high.

but if you take 90 kwhrs , and his quoted loads, which again seem a bit low... but maybe he doesn't do much, you don't know. factor in some system effcencies I can get around 22-23 kwhr/day of electricity stored in form of hydrogen which seems reasonable to carry him through the winter if his loads are as stated.

as far as the electrolzer goes it is a pressureized PEM electrolyzer. it produces H2 at 30 bar at approx 60-65% eff. So he can store h2 at 30 bar at 60-65% eff.. if needs to compress further to say 200 bar it would cost him about 5% of the heating value of the H2 to do that.

So, I'm going to say that this system is feasible if his stated loads and his solar production values are correct.

Also where did you get 66% eff for FLA batteries? Use FLA systems are modeled at 85%. 66% is flow battery levels and seems really low for FLA.

As far as the whole hydrgen thing goes. For all you critics out there please tell me how you can store large amounts of energy 10s-100s MWhr in a system that has no emissions and flexible enough to have the ability to be applied through out the world. Yes the effcencies of hydrogen suck, that is because you have to generate the fuel and then consume it. the Thermodynamic gods are taxing you twice, but please give me another reasonable system that can meet this need.
 

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Discussion Starter #9 (Edited)
Also where did you get 66% eff for FLA batteries? Use FLA systems are modeled at 85%. 66% is flow battery levels and seems really low for FLA.
I was being very generous with 66%.Realistically 50%

You are only considering 80% for the batteries, and ignoring the losses in wiring between the panels to charge controller, charge controller to batteries, battery to inverter, charge controller and inverter conversion efficiency. If using a MPPT charge controller, the best you can get is 66% if you utilize every watt hour generated. If you use a shunt type charge controller the best you can get is 50% as you loose 30% just as heat loss in the controller alone (Voltage drop) because input current = output current. MPPT controllers run around 95% when operating at full capacity. So when you add all the losses up in a battery system 66% is the absolute best in theory.

The best designed Grid Tied systems are only 77 yo 80% efficient.
 

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Discussion Starter #10
So, what's the issue with generating hydrogen to take full advantage of a PV system?
Simple, it is a huge waste of resources. Batteries are much more efficient and much less expensive.

The problem with a hydrogen economy boils down to this. Hydrogen is only a carrier of energy, not a source of energy,and there is no free hydrogen on this 3rd rock from the sun, it must be manufactured from other elements like water or as it is today commercially 100% from Natural Gas. Therefore the Second Law of Thermodynamics cannot be worked around and hydrogen will always be a high multiple of the source fule and will always be in competition with the source fuel. Even if that source is a renewable fuel like solar or wind. As a consumer tell me which you will buy? A Kwh from the solar farm at 20-cents, or $2 from the hydrogen plant? Who will stay in business? The electric company or the hydrogen company? :eek: ;)
 

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Yeah that is the big lie when he says he will never pay a another dime for electricity. Off-Grid battery systems will cost you a minimum of 10 times more for electricity than buying from a electric company. He failed to mention all those batteries have to be replaced every 5 years or so at a cost of around $100K or more. :eek:
At a minimum off-grid systems seem to be approaching the price of grid power. LFP cells for instance are approaching ~8c/kWh stored, and in states that have good solar panel system rebates, power can be very cheap too, ~2-6c/kWh. Provided there's a bias towards staggered daytime operation of appliances and whatnot to avoid the ~8c/kWh storage cost on most of the electricity used, it may even be able to go off-grid for under the grid rates.
 

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Discussion Starter #12
it may even be able to go off-grid for under the grid rates.
Sorry but I design/build a lot of grid tied systems and it is not even remotely possible. More like paying 5 to 10 times more for electricity for the rest of your life unless you live like a hermit and only use 1 or 2 Kwh per day and your electric company charges you outrageous monthly minimum service and/or connect charges.

Here is a modest model to demonstrate. A 10 Kwh off-grid battery system in Kansas City MO.

Solar panel wattage and cost = 6000 watts @ $2 per watt = $12,000
80 Amp 48 volt MPPT Charge controller = $500
5-year 50 Kwh reserve capacity FLA battery = $110 per Kwh = $5500
2000 watt True Sine Wave inverter = $2500
Miscellaneous hardware, cable, wiring, and material = $3000
Equipment cost not including any labor or permit fees = $23,500

OK to compare cost we look at the first 5 years because after 5 years you have to replace the batteries at even higher cost 5 years down the road. So a 10 Kwh system will generate 10 Kwh x 1825 days = 18,250 Kwh in 5 years. That gives you a cost of $23,500 / 18,250 Kwh = $1.29 per Kwh. Going rate in KCY is 12 cents per Kwh or for 5 years will cost $2,190.00. After 5 years replace the batteries of $6000. You will never break even., it is just not possible.
 

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I think it's not a simple as you're making it out to be and that you dismiss it too easily. I'm going to try to resist replying like it's an argument and do some research and get back to this whole discussion. I will add some thoughts below. I know I don't have all of the answers, but I think I bring up some good questions.

Simple, it is a huge waste of resources...
What type of resources are you talking about? Money? Energy? Time? And, why? There's absolutely no use for hydrogen as an energy carrier?

Sunking said:
Batteries are much more efficient and much less expensive...
In the case we're discussing, it sounds to me like there is already a large battery bank. At what point do other means of storage become more beneficial? In other words, should a huge building have an equally huge battery bank?

Are batteries are universal solution? Again, how does life cycle fit into the equation?

Sunking said:
... The problem with a hydrogen economy boils down to this. Hydrogen is only a carrier of energy, not a source of energy,and there is no free hydrogen on this 3rd rock from the sun, it must be manufactured from other elements like water or as it is today commercially 100% from Natural Gas. Therefore the Second Law of Thermodynamics cannot be worked around and hydrogen will always be a high multiple of the source fule and will always be in competition with the source fuel. Even if that source is a renewable fuel like solar or wind. As a consumer tell me which you will buy? A Kwh from the solar farm at 20-cents, or $2 from the hydrogen plant? Who will stay in business? The electric company or the hydrogen company? :eek: ;)
A battery is also an energy carrier, not a fuel source, and there are no free batteries, either. They are typically built from petroleum products, toxic metals and such, and then energy must be put into them. And, get this, you don't get all of that energy back! :eek:;) Like I said in a previous post, there are similar arguments against batteries/EVs.

I'm not sure I'm understanding what you mean by hydrogen being in competition with the source fuel.

Are your solar farm and hydrogen plant prices reasonable? Is that choice currently available? Is economics alone the reason to do or not do something?

Thanks,
Kurt

PS- Not that I'm a moderator, but shouldn't this discussion be in Chit Chat?
 

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Sunking,
You seem to be arguing both for and against batteries. And, you make solar sound unreasonable, so why are you in that field?

Thanks,
Kurt
 

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Discussion Starter #15
What type of resources are you talking about? Money? Energy? Time? And, why? There's absolutely no use for hydrogen as an energy carrier?
All the above because there are much more economical, efficient, and les space required for other technologies including batteries. Hydrogen has a place, but a niche IMO like submarines and spacecraft.

In the case we're discussing, it sounds to me like there is already a large battery bank. At what point do other means of storage become more beneficial? In other words, should a huge building have an equally huge battery bank?
In this case he has a way undersized battery bank for the amount of solar panel wattage he has. Typically in an off-grid battery system the minimum reserve capacity is 5 days and up to 10 days. This is done to so as not to discharge the batteries more than 20% in any given day, maximize battery life, and carry you through a couple of cloudy days. Batteries have a much higher power density there for not taking an acre of real estate to house all the hydrogen tanks.

A battery is also an energy carrier, not a fuel source, and there are no free batteries, either.
well you are correct but there is a huge efficiency issue here. Current lead acid using AGM batteries is around +90%, Lithium around 90%. Plant to wheel for hydrogen is down around 5%

I'm not sure I'm understanding what you mean by hydrogen being in competition with the source fuel.
Well think about it. I have a solar, wind, NG, nuucler, coal or whatever kind of plant generating electricity. To go to a hydrogen economy you are either going to have to use NG as it is done right now because it is the most efficient means to make hydrogen of around 60% to to fractor the hydrogen loose off methane. You are way better off just burning the natural gas and and make electricity. Regardless of the source of energy, the hydrogen will always be a high multiple of the source fuel. Like I said as a consumer which are you going to buy. 20-cents for a Kwh from say solar, or $2 from the hydrogen plant? It is a no brainier.

Are your solar farm and hydrogen plant prices reasonable? Is that choice currently available? Is economics alone the reason to do or not do something?
Of course economics is the reason. Who wants to wreck their economy? It boils down to efficiency, higher efficiency is always better in every respect
 

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Discussion Starter #16 (Edited)
Sunking,
You seem to be arguing both for and against batteries. And, you make solar sound unreasonable, so why are you in that field?
Good question. There are niche circumstances to justify off-grid battery systems just like hydrogen in space craft and submarines. That is where it is uneconomically justifiable or impossible to have commercial power installed into a site for electric power. like a remote cabin in the woods to a hermit. :D In my case all the battery systems I design are for cellular telephone towers and telemetry sites in very remote areas without electrical services.
 

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The main unresolved question for me is: How do batteries with a relatively high cost and short life cycle compare to hydrogen? Is there a point where the battery system costs more than the hydrogen system?

The points that seem to justify the inherent losses in hydrogen for this case are that the hydrogen house is using surplus solar energy to generate hydrogen, and the fuel source is water.

For the record, this discussion and the questions I raise have been on the hydrogen house, not a hydrogen economy. I see those as two very different things.

Thanks,
Kurt
 

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Discussion Starter #19
What I don't get is if you really are replacing the batteries every 5 years why not use lithium?
5 years is a middle ground number. As you know the quality of lead acid varies widely. On the low end people will go to Walmart and buy Sam's brand golf cart batteries which are a low end Interstate battery and you might get 2 or 3 years out of them, but they cost 6 to 8 cents per watt-hour. On the high end people will buy a true deep cycle battery made for renewable energy applications like a Rolls-Surrette and if properly sized and cared for you can get up to 10 years out of them (they come with a 7 year warranty) Down side is they cost 12 to 14 cents per watt hour.

But today it still really comes down to 2 things, economics and hardware. You are correct you can use a slightly smaller capacity lithium but probable not as small as you think. Minimum recommended reserve capacity for lead acid is 5 days. This gives you 2.5 days to 50% DOD before you either have to shut down, or run a generator if you have one. So minimum for lithium would be 3 days reserve capacity. Right now lithium is still not quite economical as to get the really good long lasting ones is still around $2 per watt hour last time I checked.

The other problem it is minor and easily solved is today to the best of my knowledge there are no solar or wind charge controllers made for lithium.

With all that said I am confident that lithium will reach parity with lead acid in a few short years if not sooner. When that happens there will be a shift in the RE market. Only problem I see it will probable be a Chi-Com dominated market.
 

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Discussion Starter #20
The main unresolved question for me is: How do batteries with a relatively high cost and short life cycle compare to hydrogen? Is there a point where the battery system costs more than the hydrogen system?
Kurt I do not have hard data to answer accurately. First thing I would need to know is how much did his electrolyzer cost him. I suspect well into 5 digits. Next how is it powered and what are the input requirements. If it is a AC powered device using high wattage, the inverter to run it can easily run into 5 digits.

But here is the deal with a properly sized solar panels and batteries, there is a huge difference in equipment cost. For example he claims to use 10 Kwh per day in NJ. So looking at NJ solar isolation all he needs is about a 4 Kw solar panel wattage to meet his needs in short winter days. He is up around 15 to 18 Kw. 4 Kw of solar panels comes out to $8000, vs $30,000 to $36,000 for what he has.

As for batteries he would need a 50 Kwh stack at $130 per Kwh is $6500. In addition he would probable want about a 2 to 3 Kva LP powered generator for those long cloudy spells.
 
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