A/C that runs off a battery...

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adudinsk
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Re: A/C that runs off a battery...

Post by adudinsk » Thu Sep 16, 2021 6:25 am

Yeah.. sounds like he does not have it correct.

He built a aluminum frame (that stuff that looks like a large version tinker toy) that covers the entire back of the boat.. and past the transom.
Covered 100% with panels.
And he has a pile he takes out and puts out when at anchor.

Looking at panels.
I too doubt 8000w...I would think... more like 1500w 1000w..
But he round the AC 24/day no probs and cooks on a double hot plate as needed no probs.
I think he may mean 8000w collection in a typical average day? Not sure..
Will be out at the club shortly.. and take photos of what he has perm. installed.

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adudinsk
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Re: A/C that runs off a battery...

Post by adudinsk » Thu Sep 16, 2021 6:28 am

I believe he has a 8k btu or 10k btu ac unit.. one of those stand alone ones you put in your room.. not the window..

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Jimmyt
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Re: A/C that runs off a battery...

Post by Jimmyt » Thu Sep 16, 2021 10:44 am

You've definitely captured my attention! :D
Jimmyt
P-Cub-Boo
2013 26M, Etec 60, roller Genoa, roller main
Cruising Waters: Mobile Bay, Western Shore, Fowl River

adudinsk
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Re: A/C that runs off a battery...

Post by adudinsk » Fri Sep 17, 2021 4:50 am

Yeah.. now I captured my attention.
Gonna have to take a real close look, rather than just chat about it all around the fire pit..

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adudinsk
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Re: A/C that runs off a battery...

Post by adudinsk » Wed Oct 20, 2021 4:41 am

Took a look....
He has 6 x 150w monocrystalline panels perm installed on a big aluminum rack. Did a nice job.
and 4 or 6 more stowed away to pull out as needed.
So about 900- 1500+ of solar.. active.

I think his inverter (which is huge) is several 1000 watts.. not 100% sure.

Has a bunch of Li batteries as well. Alot!

Still lots of solar...


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Jimmyt
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Re: A/C that runs off a battery...

Post by Jimmyt » Wed Oct 20, 2021 5:18 am

Yep, that is a lot of solar.
Jimmyt
P-Cub-Boo
2013 26M, Etec 60, roller Genoa, roller main
Cruising Waters: Mobile Bay, Western Shore, Fowl River

OverEasy
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Re: A/C that runs off a battery...

Post by OverEasy » Wed Oct 20, 2021 2:07 pm

So does his factory waterline still see daylight?🤔
A lotta solar…
A lotta batteries…
A lotta equipment…
A lotta framework….
Equals a lotta weight!!! :o :o

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Russ
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Re: A/C that runs off a battery...

Post by Russ » Thu Oct 21, 2021 6:07 am

OverEasy wrote:
Wed Oct 20, 2021 2:07 pm
So does his factory waterline still see daylight?🤔
A lotta solar…
A lotta batteries…
A lotta equipment…
A lotta framework….
Equals a lotta weight!!! :o :o
Ever see Highlander's boat?
--Russ

adudinsk
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Re: A/C that runs off a battery...

Post by adudinsk » Thu Oct 21, 2021 6:30 am

He did say he did not balance it originally and took on water.
Then had to move everything around … or something like that.

He has a Mac 26D

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adudinsk
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Re: A/C that runs off a battery...

Post by adudinsk » Thu Oct 21, 2021 6:40 am

Is Highhlander's the one on youtube as the "most modified mac??
(twin head sails..etc.etc.)
?

OverEasy
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Re: A/C that runs off a battery...

Post by OverEasy » Fri Oct 22, 2021 9:50 pm

Yes 👍
That’s Highlander!🙂

OverEasy
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Re: A/C that runs off a battery...

Post by OverEasy » Fri Oct 22, 2021 10:30 pm

Hi All

We’ve been kicking around what we can reasonably accommodate for solar on Over Easy.

From several sources we’ve found that 100 watts of solar cell takes up an area of approximately 54”x 39” or 2,106 sq in.

( :D :D To get to even a 1000 watts would cover an area of 21,060 sq in. Or roughly a geometry of 6ft x 24ft. This is something akin to the look of a WWII Jeep Aircraft Carrier :| :| with a mast sticking up through it. :D :D An array at 1500 watts would be 50% larger yet! :o :? :D :D )

The most we could fit on Over Easy would be 200 watts 108”x39” or 4,212 sq in. and that would require fold over panels. (The advantage of the fold over panels is the ability to use the panels to cover over the center panels and shut down power generation when not needed such as when in transit over the road or in the off season.) but we question if that would be of a significant enough benefit vs. the real estate and complexity.

We will probably start with a 100 watt array and see how it goes before considering expanding further.

What seems to make more sense to us is a small low dB 2000 watt gasoline fueled inverter generator. We would only need it if not staying in a marina and “on the hook” and primarily when it is hot & humid.

This solar/generator also works from a cost/space/weight/function basis.

I’d still like to see what an actual 800 to 1000 or 1500 watt array looks like on a MacGregor. There would be some good features that would be worth considering.

Best Regards,
Over Easy 😎😎🐩🐈

JaxMacX
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Re: A/C that runs off a battery...

Post by JaxMacX » Tue Oct 26, 2021 6:46 am

Hi, I'm pretty new to all of this, but I've been looking into upgrading our new to me boat (2002 MacX). If you were to install a 6000 watt LiPO4 system and then were to install 600 watt solar array, you would generate enough power over the day to run the AC at night to cool the boat down (approximately 10 to 12 hours of sunlight). Especially if you installed an efficient Marine AC. This Dometic Turbo DTG ( https://www.dometic.com/en-us/outdoor/c ... 9600024578 ) takes 115 AC and is 6000 BTU. It costs $2,510. It consumes 4.3 A for cooling. If you convert that over to W, that is about 516 watts. If the battery holds 6000 watts, then you could expect to get at least 11 hours of cooling.

With this setup, you could feasibly go a few days without having to top the battery off with shore power or a generator.

For solar panels, there are marine solar panels that are walk on that can be placed on the deck. Combine those with solar on the bimini, and you can get at lest 600 watts of solar generation per hour.

For the lithium battery, you could either build out your own (i'm still researching how to do that), or you can buy a modular system that equates to about 6kW. Bluetti has an expandable modular system that we are considering. Start with just one battery, then as our need increases, add more batteries on. (AC300, AC200Max, or AC200P) With the AC200P, you get 2000WH of power which if you were running a 500W AC would get you 4 hours or so.

The issues will always be weight if that is a concern for you. Lithium batteries do weight less than lead, but when you get that much battery, you are talking at least 150 to 200 pounds.

In my mind, the lithium house battery set would be a different electrical system from the other systems (lights, motor, etc). I'd probably place it in the dining seat where the ice chest was supposed to be in the MacX.

Of course, none of this is for the feint of heart. If we were to start building this out, it would easily hit $9000 to $12000. All of that for an AC that can easily run off a Honda 2200w inverter generator ($1,099). You might get 5 hours out of the generator on one gallon of gas running a 1000 w AC. It is way less expensive. The downsides are that you have a generator running at 40 to 50 db and it is burning gasoline.

As with all things, there are trade offs.

OverEasy
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Re: A/C that runs off a battery...

Post by OverEasy » Tue Oct 26, 2021 12:10 pm

Hi JaxMacx!

Congratulations on your new to you MacX!🎉🎊🍾

We are really enjoying ours!
Just about to wrap up almost 2 months on the waters of Lake Champlain in Vermont!
It has been fantastic!

Yes you are right about the technical aspects of the possibilities of running an Air Conditioning system on a Mac26 but as you also pointed out the baseline equipment cost is “very” prohibitive as is the weight penalty.

We figured the LiFe batteries for the capacity you mentioned would weigh in at roughly 250 lbs without support frames and add in another 60 lbs for the solar panels without support structure or the wiring. We figured a high efficiency marine AC unit like you described weighs about 40 lbs.
So roughly 300 lbs of the vessel load capacity is diminished which is roughly two ‘standard’ people for load calculations.

Placing the batteries in the dinette bench while having the volume will cause a list to starboard of almost 5 degrees (combined weight and height effect). So balancing it out is something to consider if one were to go that route.

Others who have gone the large battery bank tend to centerline the load or do a port/starboard & fore/aft distribution to maintain a uniform loading balance. I’ve made the temporary mistake of loading off to one side via incremental additions that I then had to reallocate once on the water. The baseline MacGregor is actually a generally well balanced boat with one lead acid battery. Adding to and taking away weight is a consideration that is often overlooked.

That the costs of going solar electric with sufficient storage capacity is very cost prohibitive as you mentioned. It could easily exceed the value of even a very nice late model MacGregor 26M, never mind our more vintage Mac26X.

Yes a gasoline powered inverter generator may not appear to be the choice of the environmental purist at first but there is actually a strong case for it when all the front end manufacturing/material/processing costs are accounted for vs. actual operational use time. For most MacGregor owners considering incorporation of A/C the annual usage is probably gonna be maybe 80 to 120 hours of operational time annually of which a fair portion could be at a marina with facilities with electric.

$1000 for the generator purchase with a 5 year operational life is about $200 annually. Add in fuel at say $4/gallon with about 1/2 gal/hr would cost times 120 hrs is roughly $240 annually. Estimated annual cost for operations is roughly $440 for go anywhere on demand power without days of recharging a battery bank at a fraction of the weight and complexity. Mind you the generator can also charge up a battery bank in much less time than a solar array would.

I’m not saying the solar electric isn’t worth pursuing but that a hybrid approach might be more functional and operationally cost effective for many MacGregor owners.

Best Regards,
Over Easy 😎😎🐩🐈

JaxMacX
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Re: A/C that runs off a battery...

Post by JaxMacX » Wed Oct 27, 2021 6:26 am

All great points!

As I said, I’m new to this whole thing 🙂

I’m definitely interested in learning more about weight distribution.

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