Generators - Is a 2000w Necessary or Practical?

jschemel

How does the Goal-Zero brand compare to Yamaha Inc Honda?

Ratkity

John&Kris said:

We just installed the Aluminum Platform on our "16Max S for the purpose of securing the Honda 2000i to it .Honda has a kit to make it harder to cut thru the handle. We plan on using the 110 power cord ,attaching it to the T@B and then plugging into the Honda

I have the kit handle for the 2000i. Just FYI, don't panic if it doesn't perfectly fit first go. You might need to get some pliers and a wee bit of force to pull one side out some.

Nomad

John/Kris - Why 110 - You can get a 30amp/110 adapter plug, use that at the generator and just use your 30 amp cable to the T@B ... Or am I missing something?

gilbutler

I purchased this 15 to 30 amp locking connector for connecting my T@B to power when at home.  http://www.amazon.com/Conntek-14205-1-5-Feet-Pigtail-Connector/dp/B001VSY6H8

I then also use a (small) 30/15 amp adapter to connect my 15 amp extension to 30 amp outlet when necessary because the 15 amp extension is so much smaller, lighter, and easier to carry around and use than the 30 amp.

 http://www.amazon.com/Camco-55233-Electrical-PowerGrip-Adapter/dp/B00192QB3I/ref=sr_1_3?ie=UTF8&qid=1450123191&sr=8-3&keywords=30amp+to+15+amp+adapter

Nomad

My generator is usually at one of the four corners of the T@B (depending on wind direction) - Don't really find the big 30amp cable to be that unweildy to lay out. Can get a little stiff if it's cold though.

ScottG

Ratkity said:

Separate AC battery charger that doesn't have the lower voltage limitations of cheaper chargers. It can even do an "equalize" charge. It acts much like the converter on board the T@B, has 3 stages.

Ratkity, what's the peak amperage output on your AC charger? How long does it typically take to get your battery back up?

I have a good 3-stage AC charger, but it only give 4.8 amps peak. I'm thinking that might be a little too "low and slow" for the amount of time I'm willing to run the generator.

John_and_Kris

PXLated Sorry for the confsion we do use the 30amp T@B cord  and plug it into the 30 amp one with the adapter

Ratkity

ScottG said:

Ratkity said:

Separate AC battery charger that doesn't have the lower voltage limitations of cheaper chargers. It can even do an "equalize" charge. It acts much like the converter on board the T@B, has 3 stages.

Ratkity, what's the peak amperage output on your AC charger? How long does it typically take to get your battery back up?

I have a good 3-stage AC charger, but it only give 4.8 amps peak. I'm thinking that might be a little too "low and slow" for the amount of time I'm willing to run the generator.

It depends on what stage the AC charger is running in:
Maintenance is 3A
Charge is 5A
Fast charge is 20A 
and
Engine Start is 75A

Most deep cycle batteries take an overnight (12-18 hrs) charge to get to a full 100%. Taking a voltage reading right after charging a battery will give you an inaccurate high reading, but putting a slight load on it for a few minutes will get rid of the surface charge or you can let a battery rest 12hrs without a load to get an accurate reading . A full 12V battery registers at 12.8V (I think Verna posted a "rule of thumb" chart for battery depletion). I don't know of any deep cycle battery that will reach 100% in a much shorter time than 12 hours. It's that last 15-20% that takes so long to recharge. I'm not sure you want to routinely quick charge any battery (and you need to vent a flooded battery).  It's the chemistry of any battery that prevents it from being charged at much greater amperage than around 5-6A. You don't want to be off-gassing explosive hydrogen from charging at too high a rate for more than a couple of hours. Another note of caution, the new microprocessor multi-stage chargers will register a near depleted 12V battery as a 6V battery (annoying).

I hope I answered your question. My charger is like yours. Low and slow will add to the life of your battery, but you are right: generators are an inefficient way to completely charge a battery, but are a great backup to extend boondocking time so your only limitations are food and tank space. Maybe someone who uses a genny exclusively for battery charging while boondocking can comment.

ScottG

Thanks, Ratkity--good info. That does answer my question, and confirms my impressions about charging limitations. While I'm pretty familier with automotive batteries, this deep-cycle stuff is a whole different animal. Good thing I have a long winter to ruminate on options before the next camping season!

John_and_Kris

PXLated. My mistake we do use the 30amp with adapter and the T@B power cord.

ChanW

PXL, thanks for keeping this on track. Very interesting and informative.

I've been thinking a generator could be a good addition, for restoring a depleted battery while boondocking, but after reading this, I have to adjust my thinking.

Ratkity, your explanation re deep cycle recharging is very helpful.

It seems, if I understand correctly, that with even only medium use of the battery, it could take a long generator run-time to properly restore it.

So, for myself, who would likely not use the AC, the generator would really only make sense as a 'last resort' for extending boondocking days, and not really for multi-day day-to-day battery recharging and maintenance.

I suppose a calculation could be made as to how many amp-hours would be likely to be used in a boondocking situation, then figure the generator's output recharge rate. That last 15-20% top-off charge-rate is slower though, isn't it? Like the charge-rate drops to 2A or something?

Sounds like solar is really the only answer to extended boondocking.

Does the 2000W generator use more gas than the 1000W does when either one is putting out an equivalent lower amperage? ie if all you need is 6A @12V to charge a depleted battery, does the larger engine of the 2000W use more gas? If not, then the larger fuel tank helps to extend boondocking days.

Nomad

ChanW - According to the Honda site, the 2000 is 46lbs vs 29 for the 1000 and you get roughly twice the gas mileage - 8.1 hrs/gal for the 2000 and 8.3 hrs on .6 gal for the 1000.

ChanW

PXL, are those 'mileage' figures specifying at what power output for each?

Nomad

No, just from the bulleted specs. On the 2000 I get more than 8 hrs if it stays in economy mode. About the only two thing that kick it into high are when the Alde kicks on and my toaster. - And AC startup but that's just for a few seconds.

Ratkity

ChanW said:

...... That last 15-20% top-off charge-rate is slower though, isn't it? Like the charge-rate drops to 2A or something?

Sounds like solar is really the only answer to extended boondocking.

Does the 2000W generator use more gas than the 1000W does when either one is putting out an equivalent lower amperage? ie if all you need is 6A @12V to charge a depleted battery, does the larger engine of the 2000W use more gas? If not, then the larger fuel tank helps to extend boondocking days.

First question: yes, the last 15-20% recharging of a battery is like stuffing a sleeping bag into it's duffle bag. It's a bit more difficult and you have to go slower to fit it all in without destroying the bag I think most maintenance chargers have an output of 2.5-3A and then float chargers run about .4-.5A (400-500 milliamps). Float chargers will not charge a discharged battery. Don't confuse a float charger with a maintenance charger; the former keeps a stored, charged battery from a slow natural discharge and the latter is stuffing that last 15-20% into the duffle bag.

2000W vs 1000W - ut oh. Physics. I'd have to research if/how the Honda engine sizes differ (as in cc) and/or if it's the inverters that are different (given the weight difference, both are probably bigger) - then, which scenario needs the most energy (fuel) to work in the three output modes: econo mode vs maintenance vs peak? Then there is engine efficiency - like cars, not all V6's are the same. Both Honda's have an output 20A for their 120AC receptacle and you only need 6A output for a charger; therefore, you are only putting a 30% load on either machine. But one machine is half as powerful as the other, and the smaller one has a significantly smaller gas tank....which will run longer with their current design? Ok, now my head hurts... any math/physics majors out there want to tackle this?

I think these are very good questions, Chan.

SweetlyHome

PXL something did not add up on your numbers so I checked the Honda website to clarify for my self.

2000W  3.4 hours @ full load (2000W) per .95 gal. tank or 2105Watts/gallon of gas (mileage) 
1000W 3.8 hours @ full load (1000W) per .6 gal. tank or 1667Watts / gallon of gas (mileage)

The 1000W unit is less efficient but runs a little longer on a tank because it generates half the power (watts)

Note: There are a certain number of watts in a gallon of gas.

Nomad

SweetlyHome - I just went by their generator home page bulleted items list...

SweetlyHome

PXL,
Click the individual generator and then the specs tab for each model that's where the detail comes from.  8.3 and 8.1 hours are the 1/4 load (250 watts and 500 watts) estimates.  In real use you would get somewhere in between the two estimates or better if you run less than 1/4 load.  All this line up with what Ratkity said.  Note the 1000W is rated to output 12 volts up to 96 watts.  So this would run well over 8 hours on a tank of gas just charging a battery.

Nomad

As I've mentioned, solar is what I rely on and find that even when overcast (as long as it's not "dark" and stormy) it keeps my battery charged. The gen is mainly backup. The 2000 (even though small) is somewhat of a beast to lug in/out of the Jeep so the 1000 has a certain appeal.

ChanW

Ratkity, of course it's all full of variables, and the only real way to know would be to measure it in a controlled (preferably dust-free) environment, using 3rd-year calculus. B-)

But I think going with the manufacturer's specs will probably do, since they're using 1/4 load...

That's @ 20A at 12V for the 1000W. It'd be interesting to know how much less gas you use when only drawing, perhaps 4A. (And if the Honda is running in 'quiet mode' at that output).

I too like the idea of using propane, if it's reasonably efficient. Less fuel to deal with. I looked into a conversion kit for my home genny - @ $200, if I remember right.

Nomad

Propane ... I've got a 20lb in the T@B, a spare 20lb that I haul out when baking on the grill. I'd need a third if I ran the generator as none of those three are located close to each other. Obviously the one is in the T@B tank cover. The grill is on the picnic table 15 ft away and the generator is behind the T@B so the wind blows the exhaust away.
I stop at gas stations far more often than I stop to find propane. I'm already dealing with two fuels.
As far as I can see, the only advantage might be that the gen runs longer on the propane.

DurangoTaB

Here's a twist I haven't seen posted...our Tacoma has a 400watt 110V outlet in the back of the truck bed.  Since we don't plan on using the A/C unless hooked up, and we have an 80watt Zamp, but in a pinch, could we plug in a charger?  Out quick/trickle charger draws 2amps (220watts) and puts out 2-6 amps at 12V DC.  But I guess running the truck as a generator for and hour just to get 6Ah wouldn't be practical...any thoughts?

Nomad

I've hooked up to the TV thru the seven pin for a quick hit of juice.

Ratkity

DurangoTaB said:

Here's a twist I haven't seen posted...our Tacoma has a 400watt 110V outlet in the back of the truck bed.  Since we don't plan on using the A/C unless hooked up, and we have an 80watt Zamp, but in a pinch, could we plug in a charger?  Out quick/trickle charger draws 2amps (220watts) and puts out 2-6 amps at 12V DC.  But I guess running the truck as a generator for and hour just to get 6Ah wouldn't be practical...any thoughts?

Hi Durango, I found this interesting list of appliance wattages (not the monthly kWh cost, but the wattage pull in the descriptors): http://www.duke-energy.com/pdfs/appliance_opcost_list_duke_v8.06.pdf

You can't run your ceramic heater, but easily run a computer or automotive charger (listed as 220W). If your Tacoma has that inverter, I'm going to make the assumption that Toyota put in a heavy duty alternator whose output can handle at least a 5 amp pull, if not 10 (probably max).  Charging any battery via gas engine is inefficient, but works in a pinch.

Looking at the Duke Energy list, looks like you are safe and can run a blender for the margaritas! Oh, and a can opener. PXL's toaster is out, but with his Q chef skillz, he's got backup. Or, make toast the way I do.. butter both sides and fry a couple pieces on a flat skillet, place favorite cheese in center of both pieces, set aside and let cheese melt. Then, warm up some creamy tomato bisque..... hmmmm... comfort food.

Traildale

An alternative to shorten recharge time would be to add something like a Goal Zero battery pack and use that for lighting and computer charging etc. which would reduce the discharge on the house battery over the course of a day - and it has other uses outside of the camper.  Then the generator could recharge both batteries at the same time - possibly cutting the run time in half - given the same overall power usage divided between two batteries. 
Also, I can confirm that a Honda 1000 will run the AC in a 2016 Max S with no problem. I have both the 1000 and 2000 Hondas and just started carrying the 1000.  I run it at full RPM to cover the compressor in-rush current and flip it to economy mode and the RPMs drop in half while cold air pours out of the AC. I was skeptical but pleasantly surprised.  I can easily carry the much smaller 1000, multiple power cords, a cable  lock, tongue lock, and 24 hours of generator gas in a tongue box. The 1000s are on sale through the end of the year for $699. Pictures of the generator,box attached.