Combining Wind and Solar Charge Inputs

[Target9000]

Guys,

I've searched and read tons and tons but I still can't understand a few things and was looking for some help.

My rewire project is coming up and I have a few questions.

1) Everyone says the proper way to size a boat's battery system is to make an electrical budget. However, we've never cruised, don't know our cruising habits, and everything is an estimate at this point. I did attempt it anyway and figure on roughly 100amps a day. So question one, How do you make a budget if you're totally new to cruising and don't know your own habits yet?

2) Our boat had wind and solar hooked up directly to the battery bank. When I rewire I wanted to use a newer wind generator and MPPT for the solar panels. However, the wind generator I want is the D400 which seems to be sold in a kit with a flexcharge controller and dump load. The manuals all show the solar going through this controller as well. But that isn't MPPT is it? Now I asked flexcharge and they said to ditch the MPPT and put everything through their controller. They said multiple controllers can conflict. So... How do you properly combine multiple charging sources like this?

3) I really want a D400 wind gen based on reviews. Our boat (a double ender) has very few "good" mounting locations for solar and I figure I can at least attempt to make up for that by mounting the best wind gen we can find. However, some of the other cheaper wind gens have good reviews and most others don't seem to need a shunting regulator and dump load. It would seem they are a lot more "simple" not to mention a lot cheaper. In my shoes, would you spring for the D400 or go with say an new Air Breeze or KISS wired straight to the bank?

Thanks for any advice. Sorry if these questions have been answered before, I did try an exhaustive search on combining charge sources and just haven't been able to wrap my head around the proper way to do it when you want to have multiple charge controllers involved.

[noelex 77]

Multiple charge controllers do not cause any problems and provided redundancy, but MPPT only makes a small difference so it may not be worth the trouble to install another controller if the D400 will handle solar input as well.

It is hard to do an electrical budget without using the boat. Good advice is to use the boat for a few months before you make any changes (not just electrical), but this is not always practical.

[Target9000]

Originally Posted by noelex 77

It is hard to do an electrical budget without using the boat. Good advice is to use the boat for a few months before you make any changes (not just electrical), but this is not always practical.

Thanks for the input on the multiple charge controllers. I got confused hearing different things from so many people. I guess I was putting too much stock into mppt as well.


As to the electrical budget.... The fact of the matter is that the boat's electrical system is currently in tatters and mostly unusable. Also most of the equipment on board is old and we intend to replace it, including all the lights, reefer box, etc. It just isn't in the cards to use it like it is and come up with any sort of budget that makes sense. I'm just shooting in the dark.

[noelex 77]

Yes its hard to do an energy budget with no equipment.

Put in the most energy efficient systems you can and back that up with the most solar and wind.
No one complains of having too much power.

[Celestialsailor]

It seems to me on the Flex charge, there is a leg just for wind Gen and one for solar. At least there was on my unit. Hope this helps

[Southern Star]

While I don't know what you anticipate in terms of electronics and equipment, I suspect that 100 amps is relatively low if you intend to have electrical refrigeration, radar, wind instruments, a chart plotter, SSB radio, running lights, a stereo, etc. I assume that on a Westsail 32 you intend to have a wind vane rather than an electric autopilot, but if not you will be substantially under the required capacity.

You should look at the manufacturers AMP hour ratings for various pieces of equipment and multiply by the anticipated hours of use daily. Keep in mind that many tend to under estimate the consumption and that, especially with respect to refrigeration, so much will be contingent on the amount and type of insulation in the box, the frequency that it will be opened and the ambient air (and for water or keel cooled units) water temperature.

Brad

[Bash]

The D400 puts out a lot more power than most other generators, and weighs twice as much as well. I looked at it when I selected my system, and decided it was a lot more than I needed, but that's because I have 260 watts of solar, which takes care of my energy budget pretty nicely most of the time. I like having a wind generator because I sail higher latitudes and I sail during the winter, not to mention at night. But 200 watts of wind has turned out to be plenty.

I don't know how you can decide on a system without knowing your energy needs. Other considerations are where/when you plan to sail, and what sort of boat you have. (I realize you have a double ender, but that could be anything from a skiff to a schooner.) Regardless, I would hesitate to advise you unless I knew what, when and where you're planning to cruise.

[SvLetitgo]

We did the budget exercise not a long time ago after a summer of cruising

This is the latest version.

*L* started Yoga, boat yoga that is! · SV Letitgo

Hope it help

[nigel1]

Originally Posted by Target9000

2) Our boat had wind and solar hooked up directly to the battery bank. When I rewire I wanted to use a newer wind generator and MPPT for the solar panels. However, the wind generator I want is the D400 which seems to be sold in a kit with a flexcharge controller and dump load. The manuals all show the solar going through this controller as well. But that isn't MPPT is it? Now I asked flexcharge and they said to ditch the MPPT and put everything through their controller. They said multiple controllers can conflict. So... How do you properly combine multiple charging sources like this?

Looking at a similar set up, I already have the D400, and looking at adding 2 x 135 watt panels.
Pretty sure that the regulator whcih came with my D400 does not have a solar input, but, it came from a UK supplier, so maybe different in the US.
Anyway, I'll most likely go for this
Blue Sky Energy Inc. | Solar Boost 3024iL DUO

MPPT controller to handle the solar, and the D400 hooked up direct to battery. The MPPT controller has some electronic trickery that limits the charge from the wind geny going into the batteries, or rather, from how I read it, it sucks out the excess charge and routes it to the dump resistors. The dump resistors which come with the D400 package can be used for this.
I am trying to find a way of using any excess power to heat the water. Have seen 12 volt heating coils which take the place of the dump resistors, but its finding a way of fitting the element into the HW tank, which already has a mains power heating element. Not really looked too hard into thsi bit yet, project for Dec and Jan

[Target9000]

Originally Posted by Southern Star

While I don't know what you anticipate in terms of electronics and equipment, I suspect that 100 amps is relatively low if you intend to have electrical refrigeration, radar, wind instruments, a chart plotter, SSB radio, running lights, a stereo, etc. I assume that on a Westsail 32 you intend to have a wind vane rather than an electric autopilot, but if not you will be substantially under the required capacity.

You should look at the manufacturers AMP hour ratings for various pieces of equipment and multiply by the anticipated hours of use daily. Keep in mind that many tend to under estimate the consumption and that, especially with respect to refrigeration, so much will be contingent on the amount and type of insulation in the box, the frequency that it will be opened and the ambient air (and for water or keel cooled units) water temperature.

Brad

Brad,

We anticipate using an Engel for cooling. Its a lot smaller than the current reefer setup but from the stats sheets on their site along with a lot of research and reviews it appears that they really are pretty low amp devices compared to a normal reefer box. I imagine a worst case scenario of it running continuously all day at 60amps. (which I doubt is realistic, probably looking realistically at 40amps a day).

We anticipate:
VHF
SSB (occasionally)
chartplotter
lights (all LED)
laptops and kindles
stereo (used when we have excess power)
fans for cabin
fan for head vent (always running)
Engel freezer
Fathometer
bilge pumps

We probably won't have radar or wind instruments (undecided). No TVs or anything like that. Don't anticipate having pressure water.
We do have a mechanical wind vane

So as you can see we're trying for a really bare bones cruising setup and embrace the less is more mentality.

[Target9000]

Originally Posted by Bash

I don't know how you can decide on a system without knowing your energy needs. Other considerations are where/when you plan to sail, and what sort of boat you have. (I realize you have a double ender, but that could be anything from a skiff to a schooner.) Regardless, I would hesitate to advise you unless I knew what, when and where you're planning to cruise.

Our boat is a W32. We plan a west about circumnavigation in the trades.

[Target9000]

Originally Posted by Celestialsailor

It seems to me on the Flex charge, there is a leg just for wind Gen and one for solar. At least there was on my unit. Hope this helps

Yes, this is what I was talking about. I believe the package comes with a NCHC25.

[Bash]

Originally Posted by Target9000

So as you can see we're trying for a really bare bones cruising setup and embrace the less is more mentality.

Given that, I don't see you needing more than 90 AH per day at the outside. That's certainly within the D400's capabilities until you find yourself in an anchorage where all the wind is blocked.

[Celestialsailor]

Originally Posted by Target9000

Yes, this is what I was talking about. I believe the package comes with a NCHC25.

Yep...I've had these on two different boats. There is a divert leg on them which I use on muffin fans on dorade boxes and other vents to the outside. While at anchor or the dock, they come on during the day, after the batteries are topped up, for a minute at a time. Ever since I started doing that there was never any evidence of mold.

[Target9000]

Originally Posted by Celestialsailor

Yep...I've had these on two different boats. There is a divert leg on them which I use on muffin fans on dorade boxes and other vents to the outside. While at anchor or the dock, they come on during the day, after the batteries are topped up, for a minute at a time. Ever since I started doing that there was never any evidence of mold.

Can you wire the dump resistors and the fans both in the diversion load? I mean what if the diversion has to dump a lot of amps, more than just the fans can handle?