How Much GENERATOR do I need?

[joe osborne]

Great site!
I recently purchased a 2003 Tacoma with a furnace, elec. water pump, and A/C and need to know how big of a generator I need to power everything except the A/C. I plan on using the generator during the day to charge my battery. We will only use the A/C if ther are hook ups.
Thanks
Joe

[joe osborne]

Also I'd like to add a second battery to my pup. Do I have to buy any special wiring? How do I get my converter to charge both batteries simultaneously?

[wavery]

If you are merely going to charge the battery with the generator, you can get away with a 600w generator with a 6A 12v charging circuit. However, let me just caution you that generators can get very expensive if you start small and work your way up. I have heard that old story, "I'm just going to use it for this" a 100 times. You will soon find that you want to plug something else in like a drill or a saw and a 600w generator won't run what you want. You then buy a 1000w gen and get a pittance for your 600w (because everyone is trying to get rid of those things) and so on up the $ ladder.

The other consideration is noise level. If you want to make yourself real unpopular in the campgrounds, get a cheap, noisy generator. Just make sure that your smoke alarms work and your fire insurance is paid up (just kidding :p ).

I have a Honda EU2000I and couldn't be happier with it. It will run anything that I have, including the A/C. It was a little expensive but at least I won't be climbing the $ tree.
http://www.hondapowerequipment.com/ModelDetail.asp?ModelName=eu2000i

The other issue is, the converter in your PU is probably not designed to be used as a battery charger. Most only put out about 12.2v. You need at least 13.8v (preferably 14.5v) to charge your battery. It's best to get a decent 3 stage battery charger that you can plug into your generator. Preferably a 12A minimum. The problem there is that you will need a larger generator to run that.

Adding a 2nd battery is just a matter of buying a 24 or 27 series deep cycle battery and a suitable battery box. You can buy them at Wal-Mart for a little over $100. Just hook the 2 batteries together - to - and + to + with 10g (minimum) automotive wire. The other option is to use the 2nd battery as a back-up. In that case, you charge one battery while the other battery is in use. When the battery in use drops below 12v, simply disconnect it and connect the fully charged battery. You may find that 2 fully charged batteries may last 4-6 days if you are conservative and it isn't too cold out.

[joe osborne]

Thanks Wavery I appreciate your knowledge and insight. I agree about climbing the $ ladder upgrading so paying for a good generator up front will be my plan. I have no idea how mant btu's my a/c is but I hope I can get away with using the EU2000. While doing research some of the generator websites say I need a minimum of 3000 watts to start my a/c. The brands I've considered are Honda, Yamaha, Kippor, and Coleman. A friend of mine has the Honda EU3000 and I love how quiet it is, however I don't have $2000.00 to spend. Hopefully I can find a nice used one.
Thanks again,
Joe

[tlhdoc]

I have no idea how mant btu's my a/c is but I hope I can get away with using the EU2000.

If all you want to do with the generator is charge your batteries, then just take a second or third battery along with you.  It is much easier than taking a generator, gas can, oil, etc.  
 
Now for running your AC, some people can run theirs with the the EU, I can not run my AC with that.  I purchased the Honda EU with the intent of running the AC with it and it wouldn't do it.  The generator will shut the power off to the outlet to protect itself from damage.

[tlhdoc]

Also I'd like to add a second battery to my pup. Do I have to buy any special wiring? How do I get my converter to charge both batteries simultaneously?

You will need to wire the two batteries in parallel.  Positive to positive and negative to negative.  I have done this on occasion to use the batteries, but I always charge them separately, with a regular battery charger.  If you want to charge them together, leave them wired together and plug them into the camper like normal.

[wavery]

I don't know what the deal is with the EU2000I and A/C. My EU2000I runs my Carrier AirV A/C (HeatPump) with no problems if I plug the A/C unit directly into the generator. Although, I must admit, it barely runs it and I couldn't even plug my cell phone in at the same time.

We've had this discussion here several times. It seems to work for some and not for others. I'm thinking that it may be something as simple as the amount of freon that is each individual unit. That could make one unit harder to start after cycling then another identical unit.

The nice thing about the EU2000I is that it is light enough and you can actually put 2 together to make a 4000w generator combo (which you can't do with most other generators). That is what I originally did because I was told that 1 wouldn't run my A/C. Although, in my case, 1 works fine so I sold my second generator to my brother. I considered the EU3000I but that thing weighs 134# (2000I is 46#), It's amost the same price as buying 2 of the 2000Is and it is huge. Not a good value IMHO.

Anyway, A/C or no A/C, I would highly recommend the EU2000I because it will do most everything that you need a generator to do and it does it quietly.

[griffsmom]

We have the Honda EU2000i and love it.  I can't speak to the specs of it all, but maybe my DH will see this thread and post on that.  All I know is that it is very quiet, which was a requirement for me to even get a generator at all.  If you think that you may move onto a bigger camper someday (like a hybrid or TT or bigger) you may want to consider the EU2000i which you can run in tandem with another EU2000i and cover your power needs.  I know that was a consideration that was important for my DH for when we get a hybrid some day.

[dthurk]

If you're looking for a generator ONLY for charging the battery, could you not also look to solar as an option?  It would be REALLY cheap to operate.  It would also have the advantage of being noiseless.  I saw 15 watt panels available in the Cabella's catalogue for a bit over $100.  You receive a free charge controller if you buy 2 or more panels, which can be hooked up together.  You could buy 3 or 4 panels, giving you 45 to 60 watts for less than the cost of your generator.  I seem to recall some saying they could recharge their batteries in a day with 50 watt panels.  I may be off on that figure, but it might be worth looking into.

[griffsdad]

Like my wife ; Griffsmom;  said I would consider the Honda EU2000. It's very quiet and well made. If you ever decide to run the AC then the EU2000 is not for you. You need more juice. One other consideration is later if you buy a second EU2000 you can run them together and that would be plenty of power to run everything on your RV.  This is the only generator I know that you can do that. Finally the resale value of this generator remains high.

[tlhdoc]

Like my wife ; Griffsmom; said I would consider the Honda EU2000. It's very quiet and well made. If you ever decide to run the AC then the EU2000 is not for you. You need more juice. One other consideration is later if you buy a second EU2000 you can run them together and that would be plenty of power to run everything on your RV. This is the only generator I know that you can do that. Finally the resale value of this generator remains high.

That is what I ended up doing.  Buying a second EU2000 since one would not do the job.  2 EU2000s are much easier to carry than one EU3000, but twice as many oil changes, filters to buy, etc.

[wavery]

If you're looking for a generator ONLY for charging the battery, could you not also look to solar as an option?  It would be REALLY cheap to operate.  It would also have the advantage of being noiseless.  I saw 15 watt panels available in the Cabella's catalogue for a bit over $100.  You receive a free charge controller if you buy 2 or more panels, which can be hooked up together.  You could buy 3 or 4 panels, giving you 45 to 60 watts for less than the cost of your generator.  I seem to recall some saying they could recharge their batteries in a day with 50 watt panels.  I may be off on that figure, but it might be worth looking into.

I lived with solar panels on my sailboat for 14 years and sailed 80,000 miles with them. I would consider myself pretty qualified on that subject. I depended on them a lot, as I made a lot of long ocean passages (up to 69 days at sea) and had to rely on solar because there are no gas stations at sea.

Solar panels are rated at the maximum output, with unblocked sunlight at a direct 90 degree angle. Any deviation from that greatly cuts down on the output.

You can expect about 50% efficiency for about 6 hours per day (in direct sunlight) in the sub-tropics (like SoCal or Florida). The higher the latitude you are located, the less efficient the panels. If there is any shade at all it will greatly reduce or completely kill output. Clouds are a no brainier (zippo output).

On a good day with bright sun and no shade or clouds you can realistically expect to get about 135 watts (11 amps) out of a ($300) 45w array. You can make that figure about 50% higher if you move the panels, to point directly at the sun, every hour. That would give you about 200w (17 amps).

This is about the same thing that you would get from running the generator for 1-2 hours per day with a 12A charger and the generator can also be used for MANY other things. The generator also works well on cloudy days and/or shady campsites .

That being said, you can also purchase 3 or 4 - 45w solar panels for the price of a Honda EU2000I generator (I had 4 on my boat). Now, you are talking adequate output but you are still stuck with the risk of not having enough available sunlight to do the job. A cloudy weekend will make you wish that you had a generator. The ideal set-up is to have both.

[dthurk]

Wavery, your experience with solar would be of great interest to me some time in the future.  We have not dry camped, but I would like to if a really nice opportunity presented itself.  I don't think it would take too much effort to get there from where we are now.  We have camped for 4 to 5 days at a time with electricity only.  DW doesn't seem to want to "cut the cord" so to speak.  I'm trying to convince her we wouldn't be cutting any of the "conveniences" of the PUP by going dry.  

We do own a generator, but it's one of the noisy "household" models.  I didn't buy it for camping, in fact, we hadn't even bought the camper when I bought the generator.  I had considered checking it out to see if I could mod it with an automotive muffler to quiet it down, but that's another thought for a future project.  Maybe it would work, maybe it wouldn't...but if it did, I'd have a 5500 watt generator that ran quietly.  

Solar seems really intriguing to me, and something I'm still leaning toward until good research on my part would prove to me otherwise.  I would think our electrical needs would be light, I'd be trying to get as much working on propane as possible, so solar charging might be a viable alternative and keep us in electricity indefinitely with no gas or oil to mess around with.  Seems to me it would be lighter, more compact and less messy than a generator.

Go Syracuse!  Go Orange!!

[griffsdad]

We like the Honda Eu2000i generator. It's a little expensive but your paying for quality.

 
Go Zags!! Gonzaga all the way BABY!!!!

[wavery]

The biggest hurtle that you would have to overcome is the amount of available sunlight at your latitude. You would have a few months during the summer that may be viable but for the most part, the angle of the sun at that latitude is not real favorable for solar power. I would estimate that your power production in July, Aug would be about 80% of what I posted above. Other months would be greatly degraded as the sun heads toward the southern latitudes and the angles become severe. The sunlight is very degraded at those angles because it has to travel through a thicker layer of atmosphere.

I am going to build a house near San Diego, Ca in 2010. I plan to finish the entire roof with a solar panel array. Hopefully, by that time, the gvm't will have more tax incentives and subsidies to encourage more solar power. I think that solar research is on the verge of some technological breakthroughs as well.

At that time, I will also add solar to my camper (whatever it is at that time). For now, I'll stick with my Honda Generator.

As far as your 5500w home generator is concerned. The muffler system is only a part of the noise problems from those things. Some people have successfully made sound proof containers to house them in. That seems to work out pretty well but you will need to put a pretty good sized fan in it for cooling. It's kinda like bringing along a "dog house" dedicated for your generator. It's pretty bulky.