Anyone working toward Off Grid - Page 5

Robaroni · 05-17-16, 03:12 PM

You didn't say you had no grid access. That's a different story. I'm not your enemy! I run off grid with intertie options because I can and that's still the best way to do it IF you have grid access. That's the point I'm making.

Again, my first statement was "it depends on where you live". In your case you have very low usage, do you live alone? That makes a difference too.
Insulation is fine but then if the house is too tight you need an air to air exchanger, also not everyone has the option of adding massive insulation. I think you're a relatively unique case. How many people don't have access to the grid?

Being in shape has nothing to do with living off the grid! Come on. What does it mean to be in good shape? Someone can run a marathon and think they are healthy That's called physically fit, Jim Fix ran marathons and dropped dead of a heart attack!
Being healthy is another story and, again, it has nothing to do with living off the grid!

I think we have to evaluate the op's situation and then see which is the best path to follow. Not everyone can, or should, live off the grid, it's not better or worse, it depends on variables. If you have six kids and live in the burbs' then living off the grid is probably not for you.
Rob

Redmohawk · 05-17-16, 06:34 PM

Yes there are many variables to how to live off grid , and the why can vary quite a bit to . I have grid access at my new site , old site would have cost me over $100,000 for a single swer line to the house .

Old site

It had a creak that flowed 3 to 4 L a second in low flow summer (spring fed ran all year) in high flow times It was 10 feet wide and 3 feet deep slope was 273 m length 75m fall .

I fitted a hydro ram pump at the top running off a fall of 2m that pumped water up to a 135,000 L water tank at the top of the property , this ran back down a 3 inch poly pipe to the main house and fed fire fighter sprinklers with 16m head . In a bush fire you opened one valve and 1 ah around the house was wet in a few seconds and would last several hours around the house.

Line then ran back down to the bottom of the creek for a fall of close to 100m into a pelton wheel generator producing 1000v AC run back up to the main house and used to charge a 1000 ah 48v lead acid battery bank. (ex forklift battery bought at scrap value) system was assisted with 2 kw of solar panels.

This system cost under $3000 Aus complete (using second hand bits and bobs) ran for 4 years with me looking after it , is still going strong (battery is tired but still serviceable) with a pair of green horns running it (with strict instruction written before I left) another 5 years later.

Should never have sold it (divorce and offered silly money for something I paid a pittance for 5 years before) 160 ah of bush in the hills of Victoria Australia.

If your an energy hungry type off grid solar is going to be expensive , more frugal will do just fine in temperate climates , LIPo cells are great but still very expensive , large format are pricey here and the Tesla wall costs $10K Aus for the smaller unit here.

Over 1000's of off grid setups are running and have been for years here in Aus mostly in far flung places where grid is never going to go or is just up the road but cost is prohibitive.

There are quite a few being off grid set up in towns now though , mostly enthusiasts doing fit outs the pros are all about grid Tie here . Feed in tariffs are almost non existent some company's simply take the excess and give nothing, almost all increase your monthly connection rate (some by 50%) being "on grid" is becoming less than ideal long term.

oil pan 4 · 05-17-16, 11:32 PM

I have used both lead acid and lithium.
For a large build I would stick with lead acid.
To build a 100ah 13 volt battery it would cost well over $600.
To build a 225ah 12 volt battery it would cost about half that.
Pretty easy to figure out which one I would go with.
When I need portability and high mobility I go with lithium.

Redmohawk · 05-18-16, 07:14 AM

If you factor in depth of discharge between lead acid and lithium chemistry , Lithium becomes far more cost effective in stationary large format .

If your running lead acid to a maximum of 80% discharge your 1000ah 48 volt pack (commonly used here in Aus) (and if looked after should last 15 years) is only 200ah in reality or about 8,000 watt hours in usable Ac in home after losses .

A lithium pack will live just as long at 80% discharge , so a 250 ah pack is giving you the same usable storage....

stevehull · 05-18-16, 08:09 AM

"After all that you will still need to buy a backup generator. Typically start up costs are usually starting well over $20,000."

Really? I see turnkey 10-15 kW units from Generac, and others for 1/4 of that . . .

Steve

Robaroni · 05-18-16, 11:09 AM

It depends on the application and all batteries have their strengths and weaknesses.

Lithium batteries are made of small individual cells, sure they're great - used and charged correctly - but deplete them below the minimum low point and the batteries are finished, over charge them and like AGM batteries they toast so you have to use an inverter with a variable charge algorithm and set them up properly. I don't know what systems detect bad cells, my inverters don't have that ability. I guess you have to keep an eye on your voltages.

L/A are more forgiving, yes, you have to set them up properly but they aren't as critical as lithium. I've been running Rolls for about 10 years now, but I only use them when the grid is down and for this application they're fine, in fact I think lithium batteries might even be overkill for me, I'll see when these quit which batteries are the better choice. I like AGM batteries in off grid/intertie systems. No maintenance and low usage, but they are costly for what you get so lithium might be a better choice.

Rob

oil pan 4 · 05-18-16, 04:12 PM

If my lithium batteries discharge too far one time they are likely finished.
If I charge them while the cell temperatures are below 20°F I lose 20% of their capacity.
If the charge controller shorts out their finished.

If you need more power from lead acid just buy a bigger battery. It will be cheaper than lithium.

I know only about half the amp hours are useable in lead acid.
So what? Now you just have marginally more amp hours than lithium, still for half the price.
Why else did you think I was comparing a 225ah lead to a 100ah lithium.
To me 225ah really means 110ah useable. Then day to day only around 50ah of that 225ah should be used.
With lithium you don't really want to discharge them below 40% or charge them above 90 to 95% day to day.

Still never going to buy lithium for a large stationary install.

Plus Lithium batteries are non recyclable. Lead acid batteries by weight are the most recycled consumer product on earth.

creeky · 05-18-16, 06:33 PM

Quote:

Originally Posted by Redmohawk

A lithium pack will live just as long at 80% discharge , so a 250 ah pack is giving you the same usable storage....

A lithium pack also makes your system 15 to 20% more efficient charging. And up to 40% more efficient discharging.

Lithium has a longer lifespan. It is recyclable. Safer. Virtually no maintenance.

There are those who will mistake operational needs for problems. Nothing can be done about that. Engineer solutions is what most of us do.

Some folks who own pb based systems still argue. Woad faces are common. But a couple years ago Princeton researchers proved what lithium folks have been saying. Right now lithium is cheaper on a per cycle basis than pb.

To go off grid is completely within reach. And I would suggest, the moral responsibility of those with the brains and budget to do so.

A Tesla battery or two (now available). An SMA inverter (now available). Few solar panels. Day to put it together. No worries.

Redmohawk · 05-18-16, 06:40 PM

If you discharge a deep cycle lead acid to 50% compared to 80% you've taken 10 years off its service life....

You can discharge most large format lithium down to 20% will little ill effect , management systems for lithium are common cheap and reliable , and lithium is almost 100% recyclable just like lead acid ....

Don't get me wrong , I have a 500 ah 48 volt bank of sealed AGM lead acid Mil spec units in the shed that will grow to around 2000 ah for the house I'm in. I choose these as I can buy them at scrap price after 3 years use (and I know they have sat the whole time on charge except for a few cycle capacity tests) and at 20% DOD they have a 15 year warranty, Not that I could claim it.

By the time they're dead Lithium will be as cheap as lead acid.

Robaroni · 05-18-16, 07:48 PM

Quote:

Originally Posted by creeky

A lithium pack also makes your system 15 to 20% more efficient charging. And up to 40% more efficient discharging.

Lithium has a longer lifespan. It is recyclable. Safer. Virtually no maintenance.

There are those who will mistake operational needs for problems. Nothing can be done about that. Engineer solutions is what most of us do.

Some folks who own pb based systems still argue. Woad faces are common. But a couple years ago Princeton researchers proved what lithium folks have been saying. Right now lithium is cheaper on a per cycle basis than pb.

To go off grid is completely within reach. And I would suggest, the moral responsibility of those with the brains and budget to do so.

A Tesla battery or two (now available). An SMA inverter (now available). Few solar panels. Day to put it together. No worries.

What do you do when a single cell goes bad on your lithium battery? How do you detect it?
If you have a lithium battery pack, then you have a lot of low voltage single cells. How do you change it?

With all the problems of L/A batteries they still have a place in home installs.

You keep saying "To go off grid is completely in reach." For whom? Certainly not the person living in the suburbs on a 100 x 100 lot. you can't use your situation as the paradigm for everyone. This is how people get in trouble, you have to qualify your statement.

Rob

05-18-16, 08:09 AM	#45
stevehull Steve Hull Join Date: Dec 2012 Location: hilly, tree covered Arcadia, OK USA Posts: 826 Thanks: 241 Thanked 165 Times in 123 Posts	"After all that you will still need to buy a backup generator. Typically start up costs are usually starting well over $20,000." Really? I see turnkey 10-15 kW units from Generac, and others for 1/4 of that . . . Steve __________________ consulting on geothermal heating/cooling & rational energy use since 1990

05-18-16, 11:09 AM	#46
Robaroni Journeyman EcoRenovator Join Date: Jun 2013 Location: Delhi, NY Posts: 332 Thanks: 20 Thanked 53 Times in 40 Posts	Battery choices It depends on the application and all batteries have their strengths and weaknesses. Lithium batteries are made of small individual cells, sure they're great - used and charged correctly - but deplete them below the minimum low point and the batteries are finished, over charge them and like AGM batteries they toast so you have to use an inverter with a variable charge algorithm and set them up properly. I don't know what systems detect bad cells, my inverters don't have that ability. I guess you have to keep an eye on your voltages. L/A are more forgiving, yes, you have to set them up properly but they aren't as critical as lithium. I've been running Rolls for about 10 years now, but I only use them when the grid is down and for this application they're fine, in fact I think lithium batteries might even be overkill for me, I'll see when these quit which batteries are the better choice. I like AGM batteries in off grid/intertie systems. No maintenance and low usage, but they are costly for what you get so lithium might be a better choice. Rob

05-17-16, 03:12 PM	#41
Robaroni Journeyman EcoRenovator Join Date: Jun 2013 Location: Delhi, NY Posts: 332 Thanks: 20 Thanked 53 Times in 40 Posts	You didn't say you had no grid access. That's a different story. I'm not your enemy! I run off grid with intertie options because I can and that's still the best way to do it IF you have grid access. That's the point I'm making. Again, my first statement was "it depends on where you live". In your case you have very low usage, do you live alone? That makes a difference too. Insulation is fine but then if the house is too tight you need an air to air exchanger, also not everyone has the option of adding massive insulation. I think you're a relatively unique case. How many people don't have access to the grid? Being in shape has nothing to do with living off the grid! Come on. What does it mean to be in good shape? Someone can run a marathon and think they are healthy That's called physically fit, Jim Fix ran marathons and dropped dead of a heart attack! Being healthy is another story and, again, it has nothing to do with living off the grid! I think we have to evaluate the op's situation and then see which is the best path to follow. Not everyone can, or should, live off the grid, it's not better or worse, it depends on variables. If you have six kids and live in the burbs' then living off the grid is probably not for you. Rob

05-17-16, 06:34 PM	#42
Redmohawk Lurking Renovator Join Date: Jul 2015 Location: Victoria , Australia Posts: 27 Thanks: 0 Thanked 1 Time in 1 Post	Yes there are many variables to how to live off grid , and the why can vary quite a bit to . I have grid access at my new site , old site would have cost me over $100,000 for a single swer line to the house . Old site It had a creak that flowed 3 to 4 L a second in low flow summer (spring fed ran all year) in high flow times It was 10 feet wide and 3 feet deep slope was 273 m length 75m fall . I fitted a hydro ram pump at the top running off a fall of 2m that pumped water up to a 135,000 L water tank at the top of the property , this ran back down a 3 inch poly pipe to the main house and fed fire fighter sprinklers with 16m head . In a bush fire you opened one valve and 1 ah around the house was wet in a few seconds and would last several hours around the house. Line then ran back down to the bottom of the creek for a fall of close to 100m into a pelton wheel generator producing 1000v AC run back up to the main house and used to charge a 1000 ah 48v lead acid battery bank. (ex forklift battery bought at scrap value) system was assisted with 2 kw of solar panels. This system cost under $3000 Aus complete (using second hand bits and bobs) ran for 4 years with me looking after it , is still going strong (battery is tired but still serviceable) with a pair of green horns running it (with strict instruction written before I left) another 5 years later. Should never have sold it (divorce and offered silly money for something I paid a pittance for 5 years before) 160 ah of bush in the hills of Victoria Australia. If your an energy hungry type off grid solar is going to be expensive , more frugal will do just fine in temperate climates , LIPo cells are great but still very expensive , large format are pricey here and the Tesla wall costs $10K Aus for the smaller unit here. Over 1000's of off grid setups are running and have been for years here in Aus mostly in far flung places where grid is never going to go or is just up the road but cost is prohibitive. There are quite a few being off grid set up in towns now though , mostly enthusiasts doing fit outs the pros are all about grid Tie here . Feed in tariffs are almost non existent some company's simply take the excess and give nothing, almost all increase your monthly connection rate (some by 50%) being "on grid" is becoming less than ideal long term.

05-17-16, 11:32 PM	#43
oil pan 4 Land owner Join Date: Nov 2012 Location: NM Posts: 1,026 Thanks: 12 Thanked 127 Times in 107 Posts	I have used both lead acid and lithium. For a large build I would stick with lead acid. To build a 100ah 13 volt battery it would cost well over $600. To build a 225ah 12 volt battery it would cost about half that. Pretty easy to figure out which one I would go with. When I need portability and high mobility I go with lithium.

05-18-16, 07:14 AM	#44
Redmohawk Lurking Renovator Join Date: Jul 2015 Location: Victoria , Australia Posts: 27 Thanks: 0 Thanked 1 Time in 1 Post	If you factor in depth of discharge between lead acid and lithium chemistry , Lithium becomes far more cost effective in stationary large format . If your running lead acid to a maximum of 80% discharge your 1000ah 48 volt pack (commonly used here in Aus) (and if looked after should last 15 years) is only 200ah in reality or about 8,000 watt hours in usable Ac in home after losses . A lithium pack will live just as long at 80% discharge , so a 250 ah pack is giving you the same usable storage....

05-18-16, 04:12 PM	#47
oil pan 4 Land owner Join Date: Nov 2012 Location: NM Posts: 1,026 Thanks: 12 Thanked 127 Times in 107 Posts	If my lithium batteries discharge too far one time they are likely finished. If I charge them while the cell temperatures are below 20°F I lose 20% of their capacity. If the charge controller shorts out their finished. If you need more power from lead acid just buy a bigger battery. It will be cheaper than lithium. I know only about half the amp hours are useable in lead acid. So what? Now you just have marginally more amp hours than lithium, still for half the price. Why else did you think I was comparing a 225ah lead to a 100ah lithium. To me 225ah really means 110ah useable. Then day to day only around 50ah of that 225ah should be used. With lithium you don't really want to discharge them below 40% or charge them above 90 to 95% day to day. Still never going to buy lithium for a large stationary install. Plus Lithium batteries are non recyclable. Lead acid batteries by weight are the most recycled consumer product on earth.

05-18-16, 06:40 PM	#49
Redmohawk Lurking Renovator Join Date: Jul 2015 Location: Victoria , Australia Posts: 27 Thanks: 0 Thanked 1 Time in 1 Post	If you discharge a deep cycle lead acid to 50% compared to 80% you've taken 10 years off its service life.... You can discharge most large format lithium down to 20% will little ill effect , management systems for lithium are common cheap and reliable , and lithium is almost 100% recyclable just like lead acid .... Don't get me wrong , I have a 500 ah 48 volt bank of sealed AGM lead acid Mil spec units in the shed that will grow to around 2000 ah for the house I'm in. I choose these as I can buy them at scrap price after 3 years use (and I know they have sat the whole time on charge except for a few cycle capacity tests) and at 20% DOD they have a 15 year warranty, Not that I could claim it. By the time they're dead Lithium will be as cheap as lead acid.