What can you run off a portable generator and shore power?

[Letterkenny]

Using a Honda EU2200i (non companion) connected through shore power, what can you reasonably run on the boat when connected via the shore power outlet? Assuming one item at a time, would there be enough power to run a microwave that’s on the house AC circuit? What kind of charging capacity is usually provided when having that on? What about the AC water heater? There’s some variables here but just thinking ahead for when the boat comes in. These would be the standard items installed on a modern 35’ boat for some measure of size.

[StuM]

The EU2200i is rated at 1800W (i.e. continuous draw).
Just look at the input wattage of your various appliances.

As an example, An 800W microwave will probably draw around 1200W so no problems with that one.

[CaptTom]

Stu has the simplest answer: look at the sticker or plate on the appliance which lists wattage.

Actually, I've found that the small microwaves don't use any more than the "full" rated wattage, so in Stu's example, you can pretty much go with 800W. Yes, there's a fan and some electronics, but that's minimal, at least on the microwaves I've used. Some are finicky about clean power though, especially newer ones with electronic controls. The old "dial" models may be better for this purpose.

There are marine water heaters with a 1200W element, so you're good there. Battery chargers may be rated in (maximum) Amps, so you'll have to do some math: W=A*V. In the case of a 12V charger, it's W=A*12 (roughly.) And chargers only run for a short time in bulk mode, then the current is reduced and you can run other things without worry.

We've even been able to run a small (9000 BTU) marine air conditioner on a Honda 2000W portable generator, but remember that anything with an electric motor is going to pull a starting surge current that's several times the running current. Some folks have added starting capacitors to their air conditioners to get them running on a smaller generator. The Honda is actually pretty good at handling momentary surges. But every device is different; YMMV.

[sailorboy1]

Originally Posted by Letterkenny

Using a Honda EU2200i (non companion) connected through shore power, what can you reasonably run on the boat when connected via the shore power outlet? Assuming one item at a time, would there be enough power to run a microwave that’s on the house AC circuit? What kind of charging capacity is usually provided when having that on? What about the AC water heater? There’s some variables here but just thinking ahead for when the boat comes in. These would be the standard items installed on a modern 35’ boat for some measure of size.

I can run ANY AC load on the boat. But I can normally only run 1 at a time. If solar has been good during the day I can normally run the charger plus hot water heater because the charger is at low current.

[twig]

We run a 12,000btu ac but only one thing at a time. Turn off water heater and charger when at anchor if running ac. We get about 6 hours ac on a tank of gas on a 85’ day and 70’ night

[Letterkenny]

Well this is useful. Are there any cheap and easy ways to retrofit air conditioning outside of a portable AC?

[StuM]

Originally Posted by CaptTom

Actually, I've found that the small microwaves don't use any more than the "full" rated wattage, so in Stu's example, you can pretty much go with 800W. Yes, there's a fan and some electronics, but that's minimal, at least on the microwaves I've used. Some are finicky about clean power though, especially newer ones with electronic controls. The old "dial" models may be better for this purpose..

Be careful about that advise. Here's a couple of fairly typical spec sheets - Panasonic and Samsung microwaves


I think you'll find similar figures for any microwave.

[Sailmonkey]

Originally Posted by Letterkenny

Well this is useful. Are there any cheap and easy ways to retrofit air conditioning outside of a portable AC?

If your going to DIY an A/C install, easy looks like crap and there is no cheap.

[CaptTom]

Originally Posted by StuM

Be careful about that advise. Here's a couple of fairly typical spec sheets - Panasonic and Samsung microwaves

I think you'll find similar figures for any microwave.

Right. Read the specs. My experience is with older, 800W (or so) "apartment size" or "dorm size" microwaves. New ones, especially the high-tech ones like "inverter" models, may be different. Still, those are maximum ratings. You may find they draw less continuous load. You really want a meter in your shore power panel to be able to monitor. Or at least buy a "kill-a-Watt" type monitor for the outlet. Note that the Honda's 1800W continuous rating is about the same as a standard 15A home outlet.

Originally Posted by Sailmonkey

If your going to DIY an A/C install, easy looks like crap and there is no cheap.

Without malice toward those who put a window air conditioner in their boat, I tend to agree that it's less than ideal. Not only for appearance, but these things aren't really made for the salt water environment, and they're less efficient than a proper marine water-source system. Also remember that a boat in the sun with very little insulation is going to require a lot more BTUs of cooling than even a small room in a house. The cheap window units generally don't have the capacity you need. And a proper marine unit will give you reverse cycle heat, too.

[Jammer]

Originally Posted by Letterkenny

Well this is useful. Are there any cheap and easy ways to retrofit air conditioning outside of a portable AC?

[Letterkenny]

Originally Posted by Jammer

Yea that’s a hard no.

[CaptTom]

Originally Posted by Letterkenny

Yea that’s a hard no.

OK, that last one didn't look that bad. I mean, I wouldn't do that, but at least they gave some thought to aesthetics. Not sure it's on a boat though. That looks like someone's garage wall in the background.

The middle one, again not a boat but that's kinda what I've seen, and what I was recommending against. Love the way the generator is perched on the trunk and hanging on by the power cord to the AC!

That first photo is one I've considered for years. Around here the water never gets to 70F in the hottest part of the summer. Just running sea water through a heat exchanger could, in theory, help cool and dry the air. My take is that it would be klugy and only minimally effective. Plus it would probably be just as expensive to design, test and build, and take up a lot more space, compared to a proper marine unit.