Solar panel and AC advice

[aDemilich]

I've been wondering about this- how bad is it really without AC in someplace like South Florida on a 30'ish boat with good ventilation and plenty of fans during summer? Does much of the boat being submerged in water help cool things down at all?

[Leo Ticheli]

In Pensacola, which is in the panhandle of north Florida, during the peak summer, sleeping inside the boat is usually unbearable, even at anchor with a little breeze. The cockpit is the only refuge unless you have a generator for the air conditioner.

"Fool, it's hot! I told you again! Were you born on the sun? It's damn hot!"

[waterman46]

Originally Posted by Projectfreedom

Greetings,
Planning to buy my first sailboat this Winter and need to rig it for living in the Florida summer heat.
Any advice on outfitting and cost for a 35' sailboat would be very helpful.
I guess the main question is how many solar panels will I need and how many batteries will I need to pump my cabin with AC for at least 8 hours?

Thank you

Has to be a catamaran. Then you might be able to fit enough solar panels to run AC in one of the hulls only, and at a moderate cooling compared to outside temperature. All depends on what air temperature you are aiming for. The AC will cycle on and off, so it's nearly impossible to predict accurately how much it will have to run to keep you comfortable.

Let's assume the aircon will run full time. Then the calculation is not difficult - so I won't do it, you should. Just look up a small AC unit's power draw - it will be given in Watts or KW. Multiply watts by 8 hours to get total power required for one day, and that's at 120V. Multiply by 10 to convert to 12V AH required per 8 hour run. Now multiply that by 1.1 to allow for 10% inverter conversion efficiency and wire losses.
This figure is your daily power requirement from the boat's 12V system, to run the air conditioner for 8 hours non-stop.

For re-charging batteries, figure 6A x 6 hours = 36AH per "100W" solar panel each day. You'll need enough panels to make up the daily 12V amp-hour requirement. You'll want a good smart controller also.

To calculate battery capacity required, double the AC's daily 12V AH requirement.

Now you know how many solar panels are requred, and their sizes. Figure out how to fit that on the catamaran w/o having to be stepped on, and if there is to be shading from the rig, you must also allow for that - even on a cat it can be significant.

[Bullshooter]

You realize the OP, who has a whopping 10 total posts, has been AWOL since post 5, right?

"In Internet slang, a troll is a person who starts flame wars or intentionally upsets people on the Internet."

[Sailmonkey]

Originally Posted by Bullshooter

You realize the OP, who has a whopping 10 total posts, has been AWOL since post 5, right?



"In Internet slang, a troll is a person who starts flame wars or intentionally upsets people on the Internet."

As I understood it, the OP was the one who was upset!

[sailingabe41ds]

Originally Posted by Sailmonkey

I’m waiting for a response to my dose of reality post.

Get a trailor for the sailboat and you can put lots of solar panels. One of his posts says he wants to go green...so a generator is not an option.
Looks like the OP is very inexperienced about management of power and limited resources and probably did not want to hear what we had to say and the limitations he will be faced.
On a side note, what is it about some of these people that as soon as they are told something they do not want to hear they have a meltdown temper tantrum and they are gone. I wonder how they deal with real serious life scenarios.

Abe

[thomm225]

Originally Posted by sailingabe41ds

Looks like the OP is very very thin skinned borderline on snowflake.

Abe

Snowflake? What is that?

[sailingabe41ds]

Originally Posted by thomm225

Snowflake? What is that?

I deleted that section, but a snowflake is someone who has a meltdown when dealing with a minimal stressful situation. Others use it in political terms...that was not my intention. I also thought it was apropros given that we were talking about A/C in hot weather where a snowflake would instantly melt.

Abe

[flightlead404]

Originally Posted by Projectfreedom

What do you mean more than I could fit? I see Sailboats same size running clothes washers, charging stations and a tons more.
I think so far Ive seen disinformation.

Thanks I'll do my own research from here
Obviously you have not been to South Florida. You cannot run generators at night when surrounded by million dollar mansions.

You should listen to what people tell you when you ask them something, rather than reject it out of hand because it doesn't conform to your pre-established position.

A/C that will stay ahead of a S FL summer requires a LOT of power.

Some generators are quiet and you won't notice it 20' from the boat.

[thomm225]

Originally Posted by aDemilich

I've been wondering about this- how bad is it really without AC in someplace like South Florida on a 30'ish boat with good ventilation and plenty of fans during summer? Does much of the boat being submerged in water help cool things down at all?

You have a boat and you live in Florida and you don't know?

It gets real fricking hot.

When we lost power in July in Pensacola after a hurricane, you learn real fast.

I don't mind being hot but when you are trying to sleep it's tough.

I tried the lounge chairs at the pool those nights, but it didn't help.

Another night slept on the tramp of my beach cat, but it was still super hot and I was wet with sweat a 2 am.

[thomm225]

Originally Posted by sailingabe41ds

I deleted that section, but a snowflake is someone who has a meltdown when dealing with a minimal stressful situation. Others use it in political terms...that was not my intention. I also thought it was apropros given that we were talking about A/C in hot weather where a snowflake would instantly melt.

Abe

Looks like you live in an area where the temps are pretty mild.

You might turn into a snowflake real fast along the Gulf Coast in late July thru August into early September.

[sailingabe41ds]

Originally Posted by thomm225

Looks like you live in an area where the temps are pretty mild.

You might turn into a snowflake real fast along the Gulf Coast in late July thru August into early September.

Hi..

This was referring to the OP who did not like what people had to say about solar panels not doing the job for A/C...had a meltdown and never heard from him again. Parents lived in Coral Gables...I could never survive in that weather...too fat.

Abe

[aDemilich]

Originally Posted by thomm225

You have a boat and you live in Florida and you don't know?

It gets real fricking hot.

When we lost power in July in Pensacola after a hurricane, you learn real fast.

I don't mind being hot but when you are trying to sleep it's tough.

I tried the lounge chairs at the pool those nights, but it didn't help.

Another night slept on the tramp of my beach cat, but it was still super hot and I was wet with sweat a 2 am.

I've only lived here a few months and have yet to actually sail the C&C, I've just been working on it in the boatyard trying to get it ready.

To piggyback off the OP's question a bit, how much would I need in terms of solar to be able to charge a phone and a laptop that draws 130w, while also keeping the lights on? My understanding of electrical systems on boats is still very limited.

And is running a generator at a busy anchorage a big no-no? Seems like it would get annoying very quickly for your neighbors.

[Sailmonkey]

Originally Posted by aDemilich

I've only lived here a few months and have yet to actually sail the C&C, I've just been working on it in the boatyard trying to get it ready.

To piggyback off the OP's question a bit, how much would I need in terms of solar to be able to charge a phone and a laptop that draws 130w, while also keeping the lights on? My understanding of electrical systems on boats is still very limited.

And is running a generator at a busy anchorage a big no-no? Seems like it would get annoying very quickly for your neighbors.

If your laptop is truly a continuous 130 watt draw...,I’d start with a new laptop.

Beyond that....the math is simple.

130 watts for 8 hours = 1040 watt hours.

So to support this thing for an 8 hour period you’d need solar capable of returning that amount of power to your batteries over a typical day, plus other unaccounted for loads, efficiency losses as well as make up for the less than stellar days.

[aDemilich]

Thanks! It says 130 watts on the charger- I'm not sure if it continually draws that much, but I was surprised too that it needs that much power. Unfortunately, my work requires that I use this laptop in order to connect to their VPN.