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Fuss · 05-02-2014, 06:38

Well, he said he wants to suppliment his generator charging, so the long generator runs are seemingly annoying him a little bit. Which normally means that its annoying him alot.

And besides, its not that expensive, he's just had his mast down and installed all sorts of electrical goodies. Replacing his fridge and freezer will be peanuts in comparison.

Jedi would be only too pleased to give him some pointers, I'm sure.

Solely transferring diesel into electricity without getting any propulsion benefits....Hmmmm.... That didn't give me a good feeling....Thats why I did everything I could to limit its run time.

Nowadays I only run it to make sure it works. I'd like to remove it but ......

tartansail · 05-02-2014, 06:55

One of the banes of mooring-based cruising for many of us still primarily living ashore is the need to turn off the fridge between trips to conserve the batteries. This results in warm beer -- less of an issue for some than others -- and the need to schlep perishables back and forth. Having enough solar capacity to keep the fridge on between trips is a delight. Dockhead may want to, at least, evaluate what would be required for that option in terms of solar generation and refrigeration efficiency. He clearly has plenty of battery capacity.

**Dockhead** · 05-02-2014, 06:58

Quote:

Originally Posted by Fuss

3 or 4kw/hours a day means only one thing.... rip out your fridge and freezer and replace them with a built in energy efficient installation.... I seem to remember that Jedi posted a very good writeup on this some time ago. Just so we don't have to reinvent the wheel.

I don't use that much and I have no gas, an induction double hob, a combination microwave grill and fan oven. Water boiled in an electric kettle.

Forget sizing your solar for use while onboard until you have got your consumption down.

For maintaining the batteries using solar while off the boat you need only a single panel and a good reliable regulator.

The solar charging parameters for this senario are very different from the solar charging parameters for an array to suppliment the diesel generator and also the main engine for the short runs in and out of harbour.

Well, the task I have set for my potential solar installation specifically does not include being able to live on it without running my generator. That was all laid out in the original post.

I am quite happy with electrical life on board and don't feel any pressing need to reduce consumption. When you have five or six people on board a large boat with 10 or 15 phones, tablets, and laptops to charge, five or six mouths to feed, endless pots of tea and coffee to brew with an electric kettle, and corresponding amounts of lighting and entertainment, laundry to do, heating system to run, navigation systems running 24/7, etc., etc., -- it takes a few kilowatt/hours, and I don't mind producing them with my lovely, smooth-running, almost silent Kohler genset.

The solar is just to maintain the batts when I'm not on board, and to give a little power bonus on sunny days, maybe allowing me to delay a generator run now and then when the sun is bright and power demands are light. Also to allow me to never leave the boat connected to shore power for long periods -- I really like that idea.

And so it looks like I've narrowed it down to something like one 240 watt Panasonic/Sanyo HIT panel and a Tracer MPPT controller. I've conceived a way to mount something like that on my davits which I'm hoping will not add that much to the pre-existing hideousness of my davits. The panel looks nice -- it has bypass diodes to help keep power up with partial shading, and is high voltage (43 volt maximum power voltage) to go with an MPPT controller and a 24 volt system like mine.

I thought about whether or not to keep the Rutland wind turbine in addition, but I think it's going on FleaBay.

**Dockhead** · 05-02-2014, 07:03

Quote:

Originally Posted by tartansail

One of the banes of mooring-based cruising for many of us still primarily living ashore is the need to turn off the fridge between trips to conserve the batteries. This results in warm beer -- less of an issue for some than others -- and the need to schlep perishables back and forth. Having enough solar capacity to keep the fridge on between trips is a delight. Dockhead may want to, at least, evaluate what would be required for that option in terms of solar generation and refrigeration efficiency. He clearly has plenty of battery capacity.

That's an interesting idea, and I'm in cold water here which makes seawater-cooled refrigeration quite efficient. It would of course be very cool to be able to leave refrigeration running and not throw away perishables every single time you go off the boat.

But it is an old engrained habit of mine to clean out the fridge, wash it out, and shut it down, leaving it with the door propped open, everytime I leave the boat for more than 24 hours. I used to do this even when I had shore power -- because shore power can flip off or have a plug knocked out accidentally, and what you would be left with then in your fridge is too horrible to think about.

But I would trust my own solar installation more than I would trust a shore power connection -- maybe really it's worth thinking about! The big power hog on my boat is the freezer -- I guess I could shut that down and leave just the fridge running -- hmmm.

**Dockhead** · 05-02-2014, 07:08

Quote:

Originally Posted by Fuss

Well, he said he wants to suppliment his generator charging, so the long generator runs are seemingly annoying him a little bit. Which normally means that its annoying him alot.

And besides, its not that expensive, he's just had his mast down and installed all sorts of electrical goodies. Replacing his fridge and freezer will be peanuts in comparison.

Jedi would be only too pleased to give him some pointers, I'm sure.

Solely transferring diesel into electricity without getting any propulsion benefits....Hmmmm.... That didn't give me a good feeling....Thats why I did everything I could to limit its run time.

Nowadays I only run it to make sure it works. I'd like to remove it but ......

Well, the generator runs really don't irritate me. Of course if it were free, who wouldn't like to reduce generator time, fuel consumption, etc.

But I don't think I have much potential for power saving without lifestyle changes which I don't want. I have all LED lighting already. My refrigeration is already very good -- two Isotherm systems with the passive self-pumping seawater-cooled condensors. The boxes are also made by Isotherm and are supposedly super-insulated. I doubt if I could improve much on that.

Fuss · 05-02-2014, 07:21

Good,
I also agree, you should get rid of the wind thing if it does not keep your batteries charged while you are away.

Pirate999 · 06-02-2014, 16:18

Quote:

Originally Posted by Stu Jackson

Dockhead, here's some good info including mounting and sizing.

Solar Systems: Selection, Installation & Controllers by Maine Sail SUPERB

Installing A Small Marine Solar System Photo Gallery by Compass Marine at pbase.com

Stu, thanks for posting this. It's exactly what I needed regarding my questions around solar. Like the OP, my needs are to top up/maintain when I put her on a mooring and leave for a few weeks. I have a diesel gen for anything else.

I need to replace two 30 year old solarex panels. They are on a custom built arch so I have size limitations - 17"W x 38"L (width being the limiting factor as they can be much longer) and may have found adequate replacements that will give me 110W. I had some questions around wiring and controllers and the site you posted helped tremendously. Many thanks.