| Author |
Message |
Henry R. Bergman, Jr. (Henryofcj) (63.224.197.10)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, July 05, 2002 - 2:07 pm: | |
Hello All;
Need help in figuring out my battery bank capacity. Diesel electric coach. Want to go 64 hours (two and two thirds days) MINIMUM then recharge with an eight (8) hour rate resulting in a charge-discharge cycle of around 3 days.
Also want to use electrical stuff (AC's, etc) while recharging. Do not want or need to run everything thru the invertor. Willing to run gen when AC's or other heavy stuff are running. This sizing is for primarily boondock dry camping.
Plan on the usual microwave, plus an electric 110VAC two burner cook top. No electric oven. Two rooftop AC's, planned, plus the usual inside stuff-TV, VCR, CD, etc.. Right now no electric washer/dryer.
Planning now on the Trace MC SW 2500 watt invertor with charger. How many T-105 batteries will I need? These are the golf cart batts. Figuring now on 12, but may decide 16 are better. What do you diesel electric coach people think? No propane.
Looks like the planned 7500 watt diesel genset may be slightly oversized, but may grow into it. Have plenty of chassis capacity for a large battery bank. Somewhat familiar with DC systems as have one now with the homestead. Thanks. Henry. |
FAST FRED (63.215.238.106)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, July 06, 2002 - 5:02 am: | |
For the refrigeration consider 100A used a day for a minimum of a 200A 12V batt foe each day.
This is for a Sunfrost , or other really insulated unit.
The problem is always cooking , the use of a tiny stove only means it will be on longer , so there is NO saving , except a better (slower) discharge rate on the batt bank.
You will probably have to create a cooking lifestyle of using a real stove while the noisemaker is on , flash freezing the food , and using a radar oven to reheat the preperations.
There are many books on "cooking" with a microwave , perhaps you should try the lifestyle first at home , to see if you can live with it.
There are very expensive hot water heaters that will hold the heat for a few days , but the genset might have to be super sized to run everything , at once.And the huge well insulated hot water unit will require more room as it needs to be sized for 3 days of hot water.
Recharge will also be very difficult and expensive . Unless the charger is very large for the inital re charge , the time lost there will be deducted from the finishing charge , and the batt capacity will shrink , even with Surette$ , or any good brand.
I would guess that unless vast amounts are spent on the recharge system you will need at least 24 hours of ON time to bring the E-meter back to 100%.
Total electric coaches are really NOT designed to boondock , sans gen set.
A few can do it well overnight ,(with no cooking or air cond), most just are happy to have the fridge still running in the AM.
You have chosen to "go where few have gone before" for the reason that very few will purchase , maintain or have room for a few thousand pounds of batts.
FAST FRED |
Henry R. Bergman, Jr. (Henryofcj) (63.224.197.10)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, July 06, 2002 - 3:36 pm: | |
Thanks Fred;
Yea, I am getting the same type of info from others too. Maybe I need to rethink the coach plan to include propane. Do not want to, but may have no other $choice$. Henry |
FAST FRED (65.56.26.123)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, July 07, 2002 - 7:34 am: | |
The choice is simple if you want to do long term boondockin ,
(a good lifestyle for a few days) or go for extended stays "out" ,
propane is the simple, silent, cheap, proven method of handeling most everything.
While propane it self isn't usually cheap , as were stuck paying huge markups , the bucks saved on the other methods will pay for a decade of propane .
Most cooks prefer a gas stove , and with cheap propane furnaces , hot water heaters , fridges (ok so there not too cheap), long life gen sets and even gas fired engine pre heaters the TEC coach becomes an expensive alternative .
Hundreds of pounds of batts , great monitoring & charging system, sine wave inverters ,short lived die$el noisemakers with pricy soundproofing and the constant fear of dead , needing replacement NOW batts , don't add up to a Happy Camper , to me.
The only use for a TEC coach would be for the unfortunate that camps where Air Cond is required for long periods 24/7 .
Of course TEC work great at PP (post to post) camping (if your willing to call ahead to be SURE of that 50A service) and for the folks that go to a "destination park" and usually sit for a season.
Easy choice if you have figured out what your coach needs to do for you.
FAST FRED |
Gary Stadler (Boogiethecat) (68.7.217.217)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, July 07, 2002 - 10:57 am: | |
Propane safety stuff... Hi Henry,
I see that you might have decided to put propane on your bus instead of doin it "all electric", and I'm just letting you know that I totally agree for many reasons. The first of which is simply volume and weight... to carry a given amount of energy around takes thousands of pounds of batteries, or hundreds of pounds of fossil fuels. Electrical storage has never been anywhere as efficient as fuel and won't be for a long time, probably not in our lifetimes at least.
The choices then are basically Diesel, Gasoline, or Propane. Each of these fuels carrys aproximately 20% less energy than the one next to it, ie a pound or a gallon of Propane has roughly 20% less energy in it than the same volume or weight of gasoline, which has roughly 20% less energy than an equivalent amount of diesel.
Gasoline is messy, flamable, and not many appliances work on the stuff, so it's out... Diesel for the same reason (ever dream of cooking with diesel fuel in the kitchen? YUCK!), leaving Propane which is usually the choice for most motorhomes. It has it's dangers too but if you don't "chince" it and follow some common sense ideas as you build your system, it will be fine and safe.
The basic safety thing to remember with propane is that it's heavier than air, so when you make your system, if you leave the area below it's plumbing opened to the street, even a leak will be much safer than if your leak is in an enclosed space with a bottom where the gas can "pool" which it will. That's where many accidents happen- the stuff gathers like a pool of water and gets lit by something and goes boom. My tank, my Gene, all my pipes, regulator, etc will all be completely located in areas very purposely opened to the street below.
There are a few places where the stuff has to come inside... the stove, refrige, and possibly water heater and room heaters. Where the pipe pierces the floor, use iron pipe, and locate it so that won't be broken if something slides by and whacks it during braking. Put propane detectors near (and BELOW) each inside appliance. Plumb them with metal pipe or stainless corrugated flex, but never rubber or plastic.
The tank should be set so that the main valve to turn it off in an emergency is easily accessable by hand. I know that remotely located tanks can be fixed up with electrical solenoids to do that task but I'd personally hate to trust that. And "local" shutoff valves or solenoids are a good idea at each appliance.
Regulators: A TWO stage regulator is manditory. Mount it close to the tank so your high pressure propane line is of a minimum length. And there's usually high-pressure outlets on the tank for both vapor and liquid... don't use the liquid one, and don't set your tank at an odd angle so you inadvertantly get liquid out of a vapor outlet, or you'll find your regulator freezing up and wonder why it doesn't work properly. Most RV applications use vapor only... you usually only see liquid being used where the propane actually powers the vehicle.
Another thing that few people seem to know is that all permanently mounted ASME motor vehicle tanks have a threaded overpressure "blow-off" valve that will release some or all of the contents of the tank if the internal pressure goes too high (like when the idiot at the filling station stuffs your tank too full of propane on a cold day and then you drive across the desert, getting that tank hot). As I remember, it's code that the blowoff valve either have a direct line-o'-sight path to the street at the side of your vehicle or if your tank is under the coach where line-of-sight is not possible, it must be plumbed to a safe exit point. (Scott, listen up!) That valve should, at minumum, aim down and out under the side of your vehicle so if it goes off, the gas/ liquid being vented will be aimed away from your coach, not up underneath it where the venting propane can find your nice hot engine parts or the pilot light on your water heater! Better yet is to hard plumb it with galvanized pipe to the rear of your coach high up near the roof so if it blows it will go up and away from the rear of your coach, and in the unfortunate scenerio that it gets lit somehow, the car behind you doesn't suddenly find itself following a flamethrower! Cap the end with a simple cork to keep rain out. And the size of that pipe should ideally be the same as the threads on your tank, I believe it's 3/4" minimum.
When mounting your tank, consider what would happen to it and where it would go if an accident was harsh enough to break it's mounts, or if the mounts got loose, where it would slide during heavy braking or a collision. Mount it appropriately to keep it where it belongs in an emergency. I use an extra set of safety cables just in case.
Basically follow ideas that are sensible and create your system conservatively and you'll be safe.
Cheers
Gary Stadler
110 gallons of propane and lovin it! |
johnwood (206.252.250.198)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, July 07, 2002 - 4:40 pm: | |
The next step in the evolution of the perfect coach power source will be the fuel cell that uses LP gas to produce power for the 'fridg and lights and produces hot water as a byproduct for showers and heat. They are now available for fixed home use and I am willing to bet that they will become available for RV use relatively soon.
Advantages: Absolutely quiet and vibration free. Major byproduct is CO2 and water that is close to distilled. Could probably be used to drink, but unsure at moment.
Would not surprise me if one came out that used diesel. There are prototypes using alcohol and gasoline for car powerplants.
One of these would replace a genset, a water heater, a wesbasto, your inverter (as one is built in to the unit), and a big chunk of your coach batteries!
Here's hoping!
Oh; another item that would be nice is RV specific thermoelectric air conditioning and refrigeration. This uses a peltier junction semiconductor with no moving parts and again, no noise. You can buy portable coolers like this, but I have not seen full size 'fridg and A/C; Yet! |
Bradd B. Smith (Bbsrtbusproject) (208.26.165.217)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, July 07, 2002 - 8:56 pm: | |
Just like an off the grid house, common where I live, 20 miles north of where thunder ridge electric in Sandpoint is, it can be done. The question is at what cost? Not only in ca$h, but weight, wear and tear on the coach and very high maintainence time and cost. 87% of the people in this country live on the grid for these and other reasons, and no one I know who can goes the other way. It just cost to much. So compromise set's in. Almost all coaches have gen sets, and propane. How long do you want to listen to it run, although you could offset some of that time with solar panels. Even then, the gen consumes something to get the charge back. Simple math will tell you how long and how much. Henry asked a fairly straight forward question, and this is the kind of thinking that expands our possibilities. He asked experienced folks a question, and experienced folks gave their opinions. This is a disscusion forum, not a you must do it my way or else situation. As far as old goes, most people get to be old by learning from their experiences and mistakes, some even aquire wisdom. Being old does not mean you can't be innovative or change your mind about something. It also doesn't make you automaticly right or wrong. However, when something works, it works, and all the big coach manufactures seem to agree on this. So if you have a different opinion than mine, by all means express it. But keep the personality problem to yourself, it does not make your opinion more valid! My coach won't be exactly like any of yours, but it will incorporate all the good and bad experiences you all have had, if I have any brains. This is what we come here for. If I wanted mine like any of yours, I'd pay you to do it your way. Can we get back to "discussing" now? |
Ian Giffin (Admin) (64.228.43.145)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, July 08, 2002 - 12:01 am: | |
A quick reminder, folks, that this is a moderated board and can be edited, as necessary, to provide continuity with regards to the original thread topic.
Let's argue the topic not the authors.
And... let's not discuss why we shouldn't argue the authors, ok?
Thank you.
Ian Giffin
www.busnut.com |
Jim Lawrence, DAFFYCANUCK (206.163.235.108)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, July 08, 2002 - 2:02 pm: | |
My wife and have been fulltiming in a converted coach for the last (almost) four years. We are wired completely 120v except for obvious loads such as fantastic fans.
Our cooking stove is propane and while boondocking our heat, fridge and hotwater is propane.
We operate 120v from a 4000 watt Trace Inverter (24v) and a Diesel Genset.
Our lifestyle is normal....in that we do not scrimp on power to save power. We use the microwave, popcorn maker, T.V., Sat. Dish Receiver and occasionally my wife will also use her electric curling iron.
We began our fulltiming with 4 T105's and a year later increased to 8. Charging time also increased with the 8 batteries of course. Two years later four of the 8 batteries failed. The reason??? I was not recharging them fully....which is next to impossible even with the large 120 amp three stage charger.
A battery reseller in Yuma (Trojan) advised me NOT to replace the 4 defunct batteries and continue with the remaining four.
We have been living the same lifestyle since and find we only occasionally have to run the genset more often than the usual every other day.
An aprox 2 hours recharge time is needed for the charger to drop to 'float'. My e-meter will then indicate batteries are down around 16 - 20 amp hours. Charging rate in 'float' mode is 3 - 4 amps so would require another 4 hours to fully charge....not really a good idea. I do manage to get them fully recharged occasionally with the solar panel and wind generator. I also, monthly, as recomended, equalize (30 - 31v) for a two hour period.
I also now check battery condition using a hydrometer on a regular basis. Our batteries are always now equally charged and water levels equal.
Moral of my story is I now firmly believe that MORE batteries is not NECESSARILY better.
My input....good luck |
FAST FRED (65.56.27.212)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, July 08, 2002 - 3:30 pm: | |
DIESEL or Kerosene cooking is a doable proposition only both styles of units have big drawbacks.
The Dickinson range unit is famous as a world class furnace all winter.
Turn it on in Oct and off in May if you live on the water . Come home after a week in the paying world , and your place is still toasty, sans elecrtric.
For summer cooking the units can operate with a combustion fan assist , so there quick to heat , and when out the fan will help the warm air in the stove leave.
Not practical on a MH in summer , but places with seperate galley can areas do it.
A Primus pressure Kerosene stove is superb , adjustable up to over 10,000 btu like a big commercial range , but a pad is needed to simmer .
ONLY down side is the unit needs about 45 seconds to start , with a squirt of alcohol in a priming cup.
The BTU in kerosene ( diesel works but is too smokey indoors) is far higher than in propane , so much less fuel is used.
When going off shore we bring 5Gal and it lasts most of a year, but it will use about 3 gal of alcohol on those hundreds of starts.
If anyone really wants to boondock for months on end , read any book on cruising boats , the systems were perfected decades ago.
Most here don't realize what a delight a propane fridge is , compared to the marine alternative.
First you take as much space out of your home and install 4 or 6 inches of insulation.
Then you purchase a couple of "Cold Plates" (eutetic plates) that are galv or stainless tanks that hold 60 to 75 lbs of heavily salted water.
Salt content adjusts the temp at which the captive brine (the eutetic solution) melts at , there fore detirmines the temp of the box.
Then you purchase and install a compressor and heat exchanger to cool the hot freon with seawater . Now all this , plus booster reciever , Penn Controlls ect , get bolted to the engine , where you installed a special shive with two belt groves to handle the 10HP this baby eats.
After about $2000 to $4000 of parts and a bunch of hours on installing everything your ready to chase the leaks in any new system and have !!!
Your First ICECUBE !!!
And you thought a grand for a Dometic was dear!!
Most small boats use the propulsion engine to charge batts , so even if one was willing to carry thousands of pounds of batts , the loss of the engine due to underload running is too high a price for most.
The fact that propane is heaier than air rules it out for many boats , but what a blessing in a bus!
FAST FRED |
|