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Sam Barber
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This thread is all about building mobile battery banks that are powered from your vehicles engine. These mobile battery banks are excellent solutions for people who are living off grid or just for someone who does a lot of travel and likes to stay connected. These are also good to have as extra insurance to help provide electricity for you and your family during a blackout or other disaster. One person who has made huge leaps forward in this space is Steven Harris who has been talking about these for several years! Here is a video of one of his projects.
 
Sam Barber
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Here is a picture of one of his battery banks.

http://www.scubbly.com/a/8092-87998/

 
Sam Barber
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Here are a few podcasts from the survival podcast with Jack Spirko and Steven Harris!
The most recent http://www.thesurvivalpodcast.com/falconry-with-chris-starr
Part 1 of 2 http://www.thesurvivalpodcast.com/episode-1038-steven-harris-on-battery-back-up-systems-part-1-of-2
Part 2 of 2 http://www.thesurvivalpodcast.com/episode-1040-steven-harris-on-battery-back-up-systems-part-2-of-2
Here is a link to Stevens website. http://www.battery1234.com/
 
Dale Hodgins
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If a battery bank is part of a vehicle's drive system, and they are charged by the grid or solar power, they can save energy. Batteries that are hauled around constantly as a means of keeping them charged for the cottage, are huge energy wasters. Not only are they charged using gas or diesel, often fully charged batteries add to the vehicle's fuel consumption while being driven around for hundreds of miles between uses.
 
Sam Barber
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Have you listened to the podcasts I believe that he addresses those issues in the podcast.
 
Dale Hodgins
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Sam Barber wrote:Have you listened to the podcasts I believe that he addresses those issues in the podcast.


No, and I won't. I watched that 21 minute video and nodded off a few times. A two minute video could have covered it pretty well.
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A summary and review ------ Get a battery bank for your truck. Don't short things out. Don't kill your starter battery. If you have various devices that require power, get suitable inverters to run them all. Get a big extension cord. Run it to the house. Plug your devices in. Get some good booster cables. Get a job that will supply enough disposable income to pay for a boat load of gadgets and fuel.
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He probably knows what he's doing. He sure loves gadgets. My cottage has a cord with alligator clips on it, that runs to my lights and an indoor battery. My van has a second accessory battery under the hood. I can clip to this and never drain down my starter battery. It all came with the van. Whenever I'm going somewhere, the cell phone plugs into the port that came with the van. Somehow I've lived mostly off grid for the last 15 years without filling the back of my truck with electrical gadgets. The back of my truck is reserved for rock, soil, manure, building materials and other stuff that needs space. None of these uses for a truck are compatible with constantly hauling around a mobile electronics store
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Edit --- I checked out the website and there seems to be lots of useful stuff there. Most of what is offered would not render the back of a truck less useful for regular truck type stuff. Their choice of writing their name in an American flag may seem patriotic to Americans. To me, it's weird and usually means that gun totin yokels are the target market. But that's just a cultural thing. I will check out their prices with shipping added, to see if they can beat the local auto supply that has great service and is minutes away.
 
paul wheaton
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R Scott
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This is like Paul's solar cart for us mere mortals.

I have a computer UPS system for a few critical systems in my house, but I am going to build one of these to replace it. I should be able to go from hours of backup to DAYS for about the same money as new UPS batteries.
 
paul wheaton
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I should point out that I bought the videos. I thought they were really good. (which might be obvious since I tried to get Steven Harris to come here and teach this stuff)
 
Jerry McIntire
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Dale, thanks for the summary. Saved me some time. I like the solar cart/trailer idea, only transport it when you need it, open up the solar panels to charge the batteries wherever power is needed.

Jerry
 
Estar Holmes
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This concept is really useful. In fact, I say in my simple unhooked living book -- "how come we're not all doing that?" I'm not doing it because I don't know how, esp. don't know how to do it w/ my Ford Focus. So, I was excited to see this link. But it contains way too much babble right from the start. I look forward to the day when people with good info realize that conveying info in a clear and concise manner is a learned skill. It doesn't automatically come with the technology you buy to communicate. Will have to put this on the list of things to get back to some day when I have lots of extra time.
 
Erik Little
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I like the mobile battery bank in the truck for this reason, its insurance.

You will need it when you don't have it.

I would rather have and not need than need and not have.

Overall weight of two batteries isn't going to impact your fuel economy that much (if at all).

It is better to keep the batteries fully charged by having them tied in to the vehicles electrical system when you are driving.

The cart idea is great on the farm or what have you but is impractical to tow the cart around every time you leave town that would really impact your fuel efficiency.
 
Len Ovens
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Erik Little wrote:I like the mobile battery bank in the truck for this reason, its insurance.

You will need it when you don't have it.

Fair enough.

Overall weight of two batteries isn't going to impact your fuel economy that much (if at all).

It is better to keep the batteries fully charged by having them tied in to the vehicles electrical system when you are driving.

I agree the weight in an already heavy vehicle will not make much difference. The wasted power to over charge the batteries will. The batteries will need more care and even then not last as long as they would stationary. A cheaper route... even from an ecological view, would be to haul around a small genset and a can of fuel. Same space, less weight, only gets used when needed instead of every time the vehicle moves. Batteries are less than 100% efficient at storing power and they get worse with age. If you use this power a lot (it is no longer emergency power) the equation may change.

I would suggest that a battery system used rarely would not do well charged directly from a car/truck alternator and so you would want an intermediate charge controller to keep your power batteries from boiling off when over charged.

Electricity is neat stuff and we have gotten used to it's convenience. I think we are very quick to reach for electrically powered devices for jobs something else will do just fine. (like manual tools)

Emergency power is needed for what? The only thing I can think of where I would want to have power for sure is food preservation... and even that shows some lack of planning. There are ways of keeping food that need no power... However, in our world of single small families, a freezer to keep the rest of a slaughtered animal makes sense... the battery back up should be in the same place and solar powered. Light? sleep when it is dark or use an oil lamp/candle. Your freezer supply can power a few led lights to keep you from stumbling.

So for strictly emergency use, this does not seem like a good idea. If you would be using a genset daily, the battery bank makes a lot more sense. The batteries are being discharged every day and the alternator will not over charge them. Really, the individual needs to look closely at their needs to see if this is the right solution for them.
 
paul wheaton
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Estar Holmes wrote:... it contains way too much babble right from the start.


I think that your statement tells us more about you than it tells us about the site.

I think that for most how-to stuff, there will be steps that some folks already know. They feel patronized when they watch it: "the video is full of stuff that nobody needs". At the same time, other people watch the same thing and feel there is information missing "nobody can do this because vital information is missing!" It is not possible to please all people all the time.

I face these complaints with nearly everything I create. Now, when I put something together, I feel I need to consider the complaints in the future. In my light bulb video, I put in a big chunk of stuff showing a woman using lights for 30 seconds or less because in a previous article and previous video I got dozens of responses that said "nobody ever uses a light for just 30 seconds." or "Paul Wheaton wants us to turn our lights off after 30 seconds of use."



So, to you it is "too much babble" and to somebody else they will think it is not enough. I think Mr. Harris is doing an excellent job.
 
Jerry McIntire
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Erik Little wrote:I like the mobile battery bank in the truck for this reason, its insurance.

You will need it when you don't have it.


Can't resist: I like the battery electric truck because it has all the batteries you'll need. Inverters are cheaper than batteries. But best yet, I like Len's idea: non-electric lights and tools for emergencies.
 
leila hamaya
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the first community i lived in was powered exclusively by "the rabbit that ran but never got anywhere" which was a diesel volkswagon rabbit that our resident mechanic was given by someone and couldnt fix.....it would start and run fine but wouldnt get into gear or go anywhere.... and so got turned into a diesel (an some bio diesel experiments) powered generator.

taking out all the seats and everything inside it was filled with a huge amount of batteries, turned on everyday for a certain amount of time to charge and powered the community.

ah perhaps a different idea, but this got me thinking about it, it was pretty cool....
 
Erik Little
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Len Ovens wrote:I agree the weight in an already heavy vehicle will not make much difference. The wasted power to over charge the batteries will. The batteries will need more care and even then not last as long as they would stationary. A cheaper route... even from an ecological view, would be to haul around a small genset and a can of fuel. Same space, less weight, only gets used when needed instead of every time the vehicle moves. Batteries are less than 100% efficient at storing power and they get worse with age. If you use this power a lot (it is no longer emergency power) the equation may change.


1. The power would only be wasted if it wasn't captured.

2. Unless you exactly size your genset to your load you will most likely produce more energy than you will use, why not capture that excess energy that is being produced while you drive?

3. Granted batteries aren't super efficient.

Len Ovens wrote:I would suggest that a battery system used rarely would not do well charged directly from a car/truck alternator and so you would want an intermediate charge controller to keep your power batteries from boiling off when over charged.


1. In his video he tells you to use a charge controller when you charging your batteries from your vehicle. Not sure if that part was in the video clip you watched or not.

2. My car battery lasted 6 years and GC batteries are much more resilient than car batteries.

3. In his vid he also shows you how to hook up a solar panel to your mobile battery bank.

Len Ovens wrote:Electricity is neat stuff and we have gotten used to it's convenience. I think we are very quick to reach for electrically powered devices for jobs something else will do just fine. (like manual tools)


Clearing debris after a storm with a sawzall could be pretty handy, just in case you are out of 2 cycle oil for your chainsaw.


Len Ovens wrote:Emergency power is needed for what? The only thing I can think of where I would want to have power for sure is food preservation... and even that shows some lack of planning. There are ways of keeping food that need no power... However, in our world of single small families, a freezer to keep the rest of a slaughtered animal makes sense... the battery back up should be in the same place and solar powered. Light? sleep when it is dark or use an oil lamp/candle. Your freezer supply can power a few LED lights to keep you from stumbling.


I have a refrigerator, freezer, and 2 sump pumps that I may need to run, this load doesn't require a generator but a mobile battery bank meets the need.

For the majority of people this is a very viable and doable option.


Len Ovens wrote:So for strictly emergency use, this does not seem like a good idea. If you would be using a genset daily, the battery bank makes a lot more sense. The batteries are being discharged every day and the alternator will not over charge them. Really, the individual needs to look closely at their needs to see if this is the right solution for them.


Like you said everyone's situation is unique.
 
Len Ovens
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Erik Little wrote:
2. Unless you exactly size your genset to your load you will most likely produce more energy than you will use, why not capture that excess energy that is being produced while you drive?

There isn't any "excess" after idle. Have you ever felt the effect of hitting the horn when the car is full throttle? You can feel the car slow down because of the power being pulled by the alternator. (yes I was young once ) So while you are driving around, any device (like a charger) that is drawing current will help you use more fuel to go the same distance. You will compensate by pressing harder on the accelerator... and using more gas. There is no free ride. even at idle in any newer car (less that 20 years old) the computer will add fuel to keep the idle speed where it wants it to compensate for things like cold or current draw.

For emergency use, I would still suggest a small portable generator for less than the cost of one battery (on sale... generators go on sale regularly, deep cycle batteries... never, but if they did it would be because they were old stock and not worth buying) let alone all the rest of the stuff to make this work. That is not constantly pulling energy from your car/trucks fuel, and is not constantly wearing out as you drive.... makes more sense for an emergency. As a user of UPS for computer work, I have found that invariably the UPS is not up to par when the power goes out, even when it has been tested only last Thursday.
 
John Polk
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2. Unless you exactly size your genset to your load you will most likely produce more energy than you will use, why not capture that excess energy that is being produced while you drive?


If the vehicle's battery is fully charged, there is no excess energy.

When the battery is full, the alternator essentially 'free wheels' - like it is in neutral.
When the alternator needs to provide electricity (a battery is not full), it 'kicks into gear' to accomplish this.
This creates more drag on the engine - and consequently, more fuel consumption.
Making the alternator create electricity causes the engine to use more fuel. There is no 'free lunch'.
 
Erik Little
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Len Ovens wrote:
There isn't any "excess" after idle. Have you ever felt the effect of hitting the horn when the car is full throttle? You can feel the car slow down because of the power being pulled by the alternator. (yes I was young once ) So while you are driving around, any device (like a charger) that is drawing current will help you use more fuel to go the same distance. You will compensate by pressing harder on the accelerator... and using more gas. There is no free ride. even at idle in any newer car (less that 20 years old) the computer will add fuel to keep the idle speed where it wants it to compensate for things like cold or current draw.

For emergency use, I would still suggest a small portable generator for less than the cost of one battery (on sale... generators go on sale regularly, deep cycle batteries... never, but if they did it would be because they were old stock and not worth buying) let alone all the rest of the stuff to make this work. That is not constantly pulling energy from your car/trucks fuel, and is not constantly wearing out as you drive.... makes more sense for an emergency. As a user of UPS for computer work, I have found that invariably the UPS is not up to par when the power goes out, even when it has been tested only last Thursday.


1. I don't drive full throttle, that would cause a wreck and I would get a ticket. I never said anything about driving full throttle. I did do a test while driving with my cruise set, I hit the horn and held it down (2000 Chevy Lumina). Result: The RPM gauge did not change and I heard no noticeable change in the performance of the engine. That's not to say that the computer didn't add more fuel to the engine but I doubt that it will impact the mpg as much as you allude to.

2. Duracell® AGM Deep Cycle Marine and RV Battery - Group Size SL34MAGM costs $119.88 at Sam's this is the Absorbed Glass Matt battery. I have yet to see a Genset under that price except maybe in a storm struck area after the cleanup and that's a maybe. I can get a regular Lead Acid Deep Cycle Battery for $83.72 (that's $46 cheaper than a harbor freight genset), I have never seen a Genset this cheap. Harbor Freight has an 800 Running watt genset for $129.99 on sale and that's an el cheapo (http://www.harborfreight.com/900-peak800-running-watts-2-hp-63cc-gas-generator-60338.html). Now if we are comparing the cost of an Edison Battery (like the ones talked about on the Permaculture Voices podcast) it would cost more, but those batteries last a couple decades.

3. The generator will produce more energy than you are using so unless you capture that energy you are wasting it.

4. This setup would always be in the vehicle. I personally don't want to drive around with a fuel can in my vehicle all the time.

Maybe you want to do a kickstarter to prove out how much fuel is used up to charge batteries in this type of setup.


Like you said though every person's situation is unique and we must do what we feel is best for us.
 
Erik Little
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John Polk wrote:

If the vehicle's battery is fully charged, there is no excess energy.

When the battery is full, the alternator essentially 'free wheels' - like it is in neutral.
When the alternator needs to provide electricity (a battery is not full), it 'kicks into gear' to accomplish this.
This creates more drag on the engine - and consequently, more fuel consumption.
Making the alternator create electricity causes the engine to use more fuel. There is no 'free lunch'.


http://www.firestonecompleteautocare.com/cf/batteries/your-cars-electrical-system/

The alternator keeps the electrical system going based on this site.

I didn't say there was a free lunch, I don't think that the "extra fuel" consumed is that significant.
 
Len Ovens
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Erik Little wrote:
I didn't say there was a free lunch, I don't think that the "extra fuel" consumed is that significant.


In a vehicle with really good gas mileage, means about 1/3 of the energy in your gas gets to the crankshaft. Then there is the loss from there through the pulley and belt to the alternator. Then the alternator has losses in it (thats why the rectifiers are on heat sinks), both mechanical and electronic... There is loss in the cable that goes from the alternator to the second charger. The second charger is always drawing some current even when the battery is fully charged or even when the battery is disconnected for that matter. The second charger also has losses all the way through and even at a trickle charge energy is going into battery, that is gas out of your tank every second the engine is running. Then when you finally do use it, there is the loss in the inverter too. If that is not significant, when does it become significant? Has anyone done even a cursory gas mileage check with such a system connected and not? Has anyone done so after the batteries are 3 or 4 years old? I would do this in a small car so the difference shows up well. Then it can be converted how much extra gas gets burned to keep it going. It would be great to then meter the outgoing power if you ever do use the setup for an emergency. Fun uses don't count, test uses don't count either, using it as remote power doesn't count... all of those things change the equation. It is the use of this setup as an emergency solution I question. Frequent remote power use, like cutting firewood or building or household power at a cottage may be a very good use for this setup.
 
Erik Little
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Len Ovens wrote:
In a vehicle with really good gas mileage, means about 1/3 of the energy in your gas gets to the crankshaft. Then there is the loss from there through the pulley and belt to the alternator. Then the alternator has losses in it (thats why the rectifiers are on heat sinks), both mechanical and electronic... There is loss in the cable that goes from the alternator to the second charger. The second charger is always drawing some current even when the battery is fully charged or even when the battery is disconnected for that matter. The second charger also has losses all the way through and even at a trickle charge energy is going into battery, that is gas out of your tank every second the engine is running. Then when you finally do use it, there is the loss in the inverter too.

If that is not significant, when does it become significant?

Has anyone done even a cursory gas mileage check with such a system connected and not?

Has anyone done so after the batteries are 3 or 4 years old?

I would do this in a small car so the difference shows up well. Then it can be converted how much extra gas gets burned to keep it going. It would be great to then meter the outgoing power if you ever do use the setup for an emergency. Fun uses don't count, test uses don't count either, using it as remote power doesn't count... all of those things change the equation. It is the use of this setup as an emergency solution I question. Frequent remote power use, like cutting firewood or building or household power at a cottage may be a very good use for this setup.



1. Based on this I would think that the loss that you are referring to is negligible, I am basing this off of using a 100 ft 20 AWG extension cord running from the inverter to the device. At 100 ft. that is equal to 0.030480 Km which equals 1.0152888 Ohm of resistance.

http://electronics.stackexchange.com/questions/58700/how-to-calculate-voltage-drop-over-and-power-loss-in-wires

Based on this article and the size of the inverter I would say that the inefficency is negligible.

http://www.solar-facts.com/inverters/inverter-efficiency.php

The loss and inefficiency of the car is already there, the only additional loss is within the battery backup system which I don't think is as significant as you think.

A loss of a couple MPG is not significant, personally I would say that a loss of 5-6 MPG would be significant. Like you said this is a personal choice. I understand you don't see the value and think its a waste of energy and you want to haul around a small genset with you every where you go, I just happen to disagree and I don't think the inefficiency is that significant to completely invalidate this setup.


2. Like I said in an earlier post feel free to start a kickstarter to pay for all the stuff and see what the actual loss is in MPG.


Do I think this setup is THE ONLY WAY, no. It is one way of many that I personally happen to like over the other options that I have seen so far.
 
Manfred Eidelloth
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Some calculation:

A small gasoline-driven current generator like the Endress ESE 2000 needs about 0.7 liter / h for a constant current output of 1000 W.
That is an efficiency factor of approximately
1 kW h / (11,3 kWh/kg x 0,75 kg/l x 0,7 l) = 16,8%


A gasoline car engine has a maximum efficiency factor of 35 % - 40%.
The realistic efficiency factor while driving is more like 15% - 20% as the engine runs at partial performance most of the time.



A car alternator usually has an efficiency factor of about 50 % - 70%, as it is optimized to be cheap and reliant and not for maximum efficiency.

This gives us an overall efficiency for current generation of about 17,5% (motor) x 60% (alternator) = 10,5 %

100 kg of extra load in the car increases the gasoline consumption of the car by about 0,3 liter / 100 km.
If we can obtain a constant electric power of 100 W from the alternator for loading our batteries and we drive at 80 km / h, than we need do go 800 km to gather 1 kWh.
This means an extra consumption of 8 x 0,3 l = 2,4 l of gasoline, just for cruising the 2 or 3 batteries and a box for them around.
To generate 1 kWh with our car while driving we therefore need
1 kWh / (11,3 kWh/kg x 0,75 kg /l x 10,5%) + 2,4 l = 3,5 liter of gasoline.
Giving us a total efficiency factor of
1 kW x 1 h / (11,3 kWh/kg x 0,75 kg/l x 3,5 l) = 3,3 %

This means: We need 16,8/3,3 = 5 times more gasoline to produce the same amount of electric energy if we use our car instead of a small generator unit.
 
Erik Little
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Manfred Eidelloth wrote:Some calculation:

A small gasoline-driven current generator like the Endress ESE 2000 needs about 0.7 liter / h for a constant current output of 1000 W.
That is an efficiency factor of approximately
1 kW h / (11,3 kWh/kg x 0,75 kg/l x 0,7 l) = 16,8%


A gasoline car engine has a maximum efficiency factor of 35 % - 40%.
The realistic efficiency factor while driving is more like 15% - 20% as the engine runs at partial performance most of the time.



A car alternator usually has an efficiency factor of about 50 % - 70%, as it is optimized to be cheap and reliant and not for maximum efficiency.

This gives us an overall efficiency for current generation of about 17,5% (motor) x 60% (alternator) = 10,5 %

100 kg of extra load in the car increases the gasoline consumption of the car by about 0,3 liter / 100 km.


If we can obtain a constant electric power of 100 W from the alternator for loading our batteries and we drive at 80 km / h, than we need do go 800 km to gather 1 kWh.
This means an extra consumption of 8 x 0,3 l = 2,4 l of gasoline, just for cruising the 2 or 3 batteries and a box for them around.
To generate 1 kWh with our car while driving we therefore need
1 kWh / (11,3 kWh/kg x 0,75 kg /l x 10,5%) + 2,4 l = 3,5 liter of gasoline.
Giving us a total efficiency factor of
1 kW x 1 h / (11,3 kWh/kg x 0,75 kg/l x 3,5 l) = 3,3 %

This means: We need 16,8/3,3 = 5 times more gasoline to produce the same amount of electric energy if we use our car instead of a small generator unit.


The portion that is in bold I question. Not sure where you are getting this number from. If you get 2 of these batteries webpage this would be 100 lbs. = 45.3592 Kg. 2 batteries, inverter, and charge controller don't even come close to 220+ pounds (100 Kg). This would change the .3 liter / 100 Km to .135 liter / 100 Km.

It also appears that you are assuming the batteries are installed without being charged up completely. If the batteries are installed fully charged then your assumptions are inaccurate. I theorize that this would also change the amount of additional fuel to maintain these batteries versus the charging that you are implying would be necessary and the additional Km that you suggest would be necessary to charge said batteries.

My point is why carry around a generator and a fuel can when you already have the fuel in the tank and an alternator? I am not saying everyone should do this or anything of the sort nor am I saying that this is the most efficient. This gives a person options when they might not have very many in a bad situation.

Also I don't read german so the graph has no meaning to me.

Like I have said many times to each their own and hey you can always do a kickstarter to show the results.
 
Len Ovens
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Erik Little wrote:
1. I don't drive full throttle, that would cause a wreck and I would get a ticket. I never said anything about driving full throttle. I did do a test while driving with my cruise set, I hit the horn and held it down (2000 Chevy Lumina). Result: The RPM gauge did not change and I heard no noticeable change in the performance of the engine. That's not to say that the computer didn't add more fuel to the engine but I doubt that it will impact the mpg as much as you allude to.


Driving at full throttle was not the point. The point was that power from the alternator is not free and it's use does affect the gas mileage. The original assertion was that power was being produced that was going to waste that could be used to charge the battery. That is false. There also seems to be the idea that once the battery is fully charged there will be no power use, also false. The idea was also floated that this would be a good way to have emergency power... that is one use in 5 years for maybe a few hours... maybe once a year in some places. I suggested that while a battery system might make sense for every day use of portable power, a small genset makes more sense for once in a while emergency use as it would not have to be live all the time.


2. Duracell® AGM Deep Cycle Marine and RV Battery - Group Size SL34MAGM costs $119.88 at Sam's this is the Absorbed Glass Matt battery. I have yet to see a Genset under that price except maybe in a storm struck area after the cleanup and that's a maybe. I can get a regular Lead Acid Deep Cycle Battery for $83.72 (that's $46 cheaper than a harbor freight genset), I have never seen a Genset this cheap. Harbor Freight has an 800 Running watt genset for $129.99 on sale and that's an el cheapo (http://www.harborfreight.com/900-peak800-running-watts-2-hp-63cc-gas-generator-60338.html). Now if we are comparing the cost of an Edison Battery (like the ones talked about on the Permaculture Voices podcast) it would cost more, but those batteries last a couple decades.


The battery is a small part of the system. What is the total cost? What I saw included a lot more than just a battery. The genset is complete in and of itself, The battery is not. Please at least add in the 1kw inverter. But wiring, charging, box... time too. The genset starts looking cheaper all the time (to me anyway). Yes, solar cells could take the load off of mileage, but then we have to add the cost of those cells and look at keeping them secure.

There may be reasons for choosing a battery over a genset. I can think noise alone may be one. However these extra considerations don't make the battery as efficient or cost effective as a genset could be, they just become other factors in the choice of a system.


3. The generator will produce more energy than you are using so unless you capture that energy you are wasting it.
[/quote
This idea comes from the same place as the idea that the alternator in a car gives free power. A genset has a throttle and a governor that matches the fuel use to the power used.


4. This setup would always be in the vehicle. I personally don't want to drive around with a fuel can in my vehicle all the time.


assuming a gasoline driven car or truck, most people already do. It is called a gas tank. I assume the reason against a "gas can" is safety, yet batteries that are always producing hydrogen gas (because they are always on some kind of charge) that must be vented have a questionable safety margin.

Maybe you want to do a kickstarter to prove out how much fuel is used up to charge batteries in this type of setup.


That would be a waste of my time and any supporter's money in my opinion. This is an idea that is great for someone who is experimenting with all of these things and understands the care of the system and uses it more often than emergency only. However, the original idea was for people who expect it to get installed and just work if and when they want it to. I think that is a bad idea that will fail someone when they need it most. That it would fail the person who doesn't understand all the ins and outs of such a system.

There is a pretty large gap between what I would use, even on a daily basis, and what I would install/set up for someone else who lacks my knowledge. It is true of computers, cars (my wife has a car we got new, I have a beater) and the list goes on. I have swapped out starters or alternators on the side of the road or in a parking lot, but I wouldn't suggest someone else do the same thing. This kind of a system would require some tech knowledge. The person who can figure it out themselves would have no problem, someone who needs instructions?... I'm not so sure.

 
Erik Little
Posts: 161
Location: USDA 5b - Central IL
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What ever you do don't use this idea Len.

Re-posting this link in case you didn't read it:

http://www.firestonecompleteautocare.com/cf/batteries/your-cars-electrical-system/

The alternator keeps the electrical system going based on this site.


I disagree on the hydrogen concern due to the velocity of the Hydrogen molecules in a gaseous state: http://physics.info/kmt/practice.shtml

Even if you factor in collisions with other molecules the hydrogen isn't just sitting there pooling up to be that dangerous. If you are that concerned about Hydrogen you could use sealed batteries. I personally am far more concerned with gasoline fumes than Hydrogen. Steven Harris addresses the Hydrogen concern in his video too.

I suggested that while a battery system might make sense for every day use of portable power, a small genset makes more sense for once in a while emergency use as it would not have to be live all the time.


You can put a switch in to turn off flow to the batteries.


I realize you don't like it and that's cool but all you do is knock it down. Maybe you could just not say anything and let people make up their own mind about it.

However, the original idea was for people who expect it to get installed and just work if and when they want it to. I think that is a bad idea that will fail someone when they need it most. That it would fail the person who doesn't understand all the ins and outs of such a system.


This was never intended for someone to have it installed and not know how it works. This is a DIY project and if you don't know what you are doing or don't feel comfortable then don't do it. There really isn't that much to this system. A genset can fail just like anything else, don't run that genset for a while and tell me how easy it is to start. Don't forget to rotate that fuel or put in some PRI-G.

In his videos he goes over everything, which you haven't watched so I understand you are speaking out of ignorance on this person's video's.


I agree to disagree.
 
Jeremy VanGelder
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Location: Proebstel, Washington, USDA Zone 6B
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Erik, if you want to do it, do it! It might not be the most effective use of space and components, but at least you will learn something.

Now, if I were driving the truck featured in the video, and I came across some fallen branches of a size which could be reasonably cut by a SawzAll, I wouldn't break out the SawzAll. I would just drive over the branches and be on my way. If I wanted to move the branches, I would drive over them a couple times until they are broken enough to clear by hand. You are still using gas, but you are using it in a much more direct manner.
 
Dale Hodgins
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I see the word "emergency" kicked around quite a bit by the purveyors of generators and batteries. Sometimes they may be used when a basement is being pumped or stuff in a freezer is about to melt.

I will never have a basement that leaks and I don't intend to have heating systems that need electricity. The loss of some convenience is not an emergency. I often live temporarily at sites where the only power is from the 12 volt port in my van, where a lighter used to be. This charges my phone which is also my flashlight, my computer and TV. I have a movie player the size of a laptop at the cottage, that runs off the same port. If a true emergency cropped up and I was unable to deal with it, I could make a call. Big battery banks and generators help people to continue living energy intensive lives when the grid fails.
 
Len Ovens
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Dale Hodgins wrote:I see the word "emergency" kicked around quite a bit by the purveyors of generators and batteries. Sometimes they may be used when a basement is being pumped or stuff in a freezer is about to melt.

I will never have a basement that leaks and I don't intend to have heating systems that need electricity. The loss of some convenience is not an emergency. I often live temporarily at sites where the only power is from the 12 volt port in my van, where a lighter used to be. This charges my phone which is also my flashlight, my computer and TV. I have a movie player the size of a laptop at the cottage, that runs off the same port. If a true emergency cropped up and I was unable to deal with it, I could make a call. Big battery banks and generators help people to continue living energy intensive lives when the grid fails.


I live in the average house in a suburban area. The only emergency power I could see needing is for the freezer. This would be a major power out as the freezer(s) act like a battery of their own so long as the lid stays closed.
 
David Seelman
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I have read several places that the Sunforce charge controllers that Steve recommends can't or shouldn't be used on AGM batteries. Any thoughts or recommendations? We are using our bank to run a block heater for an M1028. We charge the batteries when at home from grid power but would like to charge them from the engine when travelling. We went with AGM because the batteries are behind the seat.
 
Steven Harris
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David Seelman NO BATTERIES IN THE PASSENGER COMPARTMENT EVER !!! Get those batteries 'behind your seat' and get them OUT OF THERE NOW. WHEN you DO get into an accident those batteries are going to fly right through the seat, right through you and out the front window, if they don't move up and take your head clean off. The common person has NO IDEA of Crash Dynamics and the forces involved. At 50G's of force in a crash your 50 pound battery becomes a 2500 pound missile, and not much is going to stop it. I have clearly, clearly published and said NEVER put batteries in the passenger compartment EVER. I don't care if you think you've tied them down to the frame. Don't do it.
Death awaits you.

Steve
 
walt mirador
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Hello all, new member here, and thank you all for the hard work at such a great site. I am honored to be a part of this!

I know a little about alternative electricity, and wanted to share what I have discovered. Having lived off grid for 3 years, and working on a few systems, and having incorporated a few ideas like this into some vehicles, here are some thoughts to consider:

* IF you take the time to build good connections, use adequate/over-sized wires, use over-current protection, keep the batteries topped off(not too topped off... and don't use sealed batteries for your first system, especially if you are NOT electrically inclined), select a decent, well-ventilated inverter, take care of any neutral-ground-bond issues if you incorporate pass-thru AC(a DPDT relay works quite nicely), and last but not least- properly understand your vehicle's charging system and properly integrate your piggyback system into it, THEN i CANNOT EMPHASIZE ENOUGH how great this works!! I say this with all due respect to the aforementioned negative comments and concerns, (most of which can easily be mitigated with, well, dealing with my "if's" above.)

* When a vehicle is driving down the road, unless you have an EXTREMELY fuel efficient engine, there is already so much waste it isn't even funny. So to piggyback a system on the existing infrastructure is for the most part a free ride. I'm not claiming "free energy", just making the comparison to 'most' gensets to wit: once it's running, the electricity is pretty much free. I'm not talking about loading the genset clear down to 3/4 of it's rated load, nor am I talking about installing a huge battery bank in a late 70's Ford/Mopar pickup with a 'puny' 40 amp alternator. Quite the contrary, I have found a strategically implemented system will harvest LOTS of SUPER-CHEAP battery charging.

* Most of the negatives can be mitigated as follows:
1 Installing a vacuum switch to activate an isolation relay which only connects your auxiliary battery bank into the vehicle's charging system when you are decelerating(high vacuum). This is true regenerative braking, as close to free energy as you are gonna get. For those of you with a decent amount of hills to negotiate and you are able/willing to use your tranny more for braking, you can really cash in. (Of course a dash-mounted switch can manually connect the system full time as needed.)
2 Installing a higher amp alternator. You can't justify installing a smaller alternator pulley unless you intend/need to really work this system as your primary charging source, in which case it's still cheaper than running 'another' generator at home.
3 Place the batteries where extra weight will assist with traction (in the winter) if you can, and of course read previous posts for much discussion about hydrogen gas & crash dynamics. With a little care, most of you can find a 'neat' spot for the batteries. There is a point of diminishing returns as to how much battery to pack around. A full size rig can easily justify 2 golfcarts and more, whereas a Geo Metro might want to limit to 1 group 27 in the trunk(read up on safety/missiles/hydrogen gas/acid). They must be protected from the nasty salt spray in the winter, and should be protected from the weather if you can. I run some of mine inside and some outside the passenger compartment. The ones inside are sealed, and yes they will become missiles in a crash if my bracketry (quite hearty) yields to the cubed velocity forces at work. I am intimately aware of my batteries' states of charge, take felt temp readings regularly, and am taking the risk on the missiles. But should 'you' put your batteries inside- probably NOT.
4 Most of the rest is good connections, ventilation, fuses/breakers, big cables, GFI, keep it dry/don't cook it in the summer sun, etc. etc.
5 For FANTASTIC system performance, some of you can install a simple battery isolator (the ones with 3 or 4 threaded posts in the heat-sink-finned aluminum), and hook it up in an UNCONVENTIONAL and SIMPLE way as to get well over 15 volts delivered to the axillary battery bank out of your stock, unmodified alternator. As long as your alternator can remote sense voltage, this works. Really nice.

We had a full size rear wheel drive domestic car with a 65 amp plain Delco alternator with 400 lbs of battery in the trunk. Selectable switching on the dash to select no alt output(nice for cold starting), low volts (13.x to the main system and 14.x to the aux bank), and hi volts (14.x to the main system and 15.x volts to the aux bank). Batteries only in the trunk(seriously restrained) wired to a 7-wire RV plug at the rear bumper(8 gauge wires used on the ground and batt terminals of that pug believe it or not), and a 12VDC only cabin. When we got home, we parked in the same spot each time and plugged the cabin into the car. I cannot tell you how nicely this worked. 12VDC input on our only laptop at the time which mainly supplemented home schooling, 12V florescent and LED(ugly homebrew) lights, an 8 cell boombox for tunes, few other goodies and we were all set. When we went to town, we had over 3 hours of engine run time round trip. By managing the voltage select switch and looking at return amps, this old car worked out pretty nice. We even left a few lights on in the cabin when we left so when we got home in the dark and plugged the house in, voila- we could enter a lit home. I even ground the tab off the trailer plug that locks it in the receptacle so as not to destroy the harness should drive away with it plugged in, which I did once

It can be done! Look at your average drive/errand times, and I bet most of you would benefit from some version of this idea. Gotta get to working, more to follow. Hope this painted a good picture. No criticisms/questions too dumb- feel free!
 
Mike Hamilton
Posts: 82
Location: north end of the Keweenaw Mi.
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No matter what the subject is,there is always a bit of valuable information to glean from.
Thank you to Paul and Steve Harris for putting together the pod casts on different subjects
like Jack and Steve sez. ''2 is 1,1 is none,and 3 is for me'' [or some thing like that]
They encouraged me to move the alternative power source up the list for heat in the house
I need 600 watts to run the heating system in the house [pellet boiler]
So between the 4 golf cart battery's in the camper and the dual set in the ''bush truck'' we are set for storage and re charging

I just got to get a newer inverter yet

Mike

also welcome Walt to permies
 
I agree. Here's the link: http://stoves2.com
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