Solar at Anchor

[UFO]

I have 1KW of Solar, but I am getting minimal power of of it, due to the prevailing winds putting the panels in the worst possible place - It is also winter here which does not help.



I could swing the boat around and stick out a stern anchor, but that is not always feasible - I was just wondering how those living at anchor survive when this happens day after day?


I have been running the generator a lot longer than I want to.

[BillKny]

Originally Posted by UFO

I have 1KW of Solar, but I am getting minimal power of of it, due to the prevailing winds putting the panels in the worst possible place - It is also winter here which does not help.



I could swing the boat around and stick out a stern anchor, but that is not always feasible - I was just wondering how those living at anchor survive when this happens day after day?


I have been running the generator a lot longer than I want to.

Our answer is pretty simple: We run the generator more in the winter than the summer.

Our expectations might be a bit different. We expect our solar panels (650W) to supply about 3kW-hr/day which is about half our total power consumption. We expect to run our generator about 90 minutes every other day. In the height of summer its about 60 minutes, in the darkest of winter its about 120 minutes.

As our grid operators already know, solar is not 100% reliable.

[Reefmagnet]

Adjustable panel mounts and the best thing ever invented - a solar blanket.

[Tomodore]

It is amazing how often the panels point badly. Yes use dead dinosaurs, in our case we have no generator so we run the engine in reverse at anchor and smile while 60 amps flow into our batteries. 8 years so far on this engine and 4000 hours. Figure 12 more years to 10,000 and rebuild, I’ll be 80 then and happy to rebuild or repower if I am still floating.

[Simi 60]

We have 2500watts on the roof with space for another 1500 watts.
Always need an hour or two of Genset in winter.
In summer we can't use enough power.

[seandepagnier]

I never had a generator and always have plenty of power from solar.

I have only half my panels out in the summer, but in the winter I use all of them. I don't have as much solar as you, a bit less than half. I mostly soak up the excess power running the 3d printer 5-6 hours a day and charging electric bicycle battery and electric cooking. I also keep a few computers running 24 hours a day.

Most likely you are just not efficiently using the power you have, not set up with an efficient system, and wasting the energy on non-useful purposes. It makes no sense you would run out of power with 1kw of solar even in winter unless you are beyond 45 degrees latitude.

Even in overcast conditions day after day in winter I make enough power. You should give more details about what you are powering as this is probably the real problem.

[UFO]

Originally Posted by seandepagnier

I never had a generator and always have plenty of power from solar.

I have only half my panels out in the summer, but in the winter I use all of them. I don't have as much solar as you, a bit less than half. I mostly soak up the excess power running the 3d printer 5-6 hours a day and charging electric bicycle battery and electric cooking. I also keep a few computers running 24 hours a day.

Most likely you are just not efficiently using the power you have, not set up with an efficient system, and wasting the energy on non-useful purposes. It makes no sense you would run out of power with 1kw of solar even in winter unless you are beyond 45 degrees latitude.

Even in overcast conditions day after day in winter I make enough power. You should give more details about what you are powering as this is probably the real problem.

We are a family of 4 with a friend currently on board. We have 2 x small 12v Fridge and 1 x small 240V Freezer. Plus Laptop and a couple of Pads, phones and 4GX wireless modem for internet. All cooking is gas and all lights are LED. We also have electric toilets and presurised water system. We also run a cheap arse small 240V washing machine for 30-40 mins every 3-4 days when no launderette is available.



When we get a good day of sun on the panels even in winter it is all good, its just that we have had a lot of rain intermixed with days when the wind is turning the panels away from the sun for the whole day.

[noelex 77]

Having solar panels in a location that is as shade free as possible makes a huge difference to the output. Try and avoid mounting aerials and other structures above the panels.

Swinging the boat at anchor can be a useful technique to avoid shade from the mast. Often a spring line to the chain is enough, although I have occasionally resorted to anchoring from the stern, but this was in days of 75w of solar producing all our power.

The other important consideration is reducing consumption while maintaining functionality. Most boats waste considerable amounts of power.

1000w of solar in Perth will still produce reasonable amounts of power even in winter, and self sufficiency without a generator while still enjoying a comfortable lifestyle is not an unrealistic goal.

[GordMay]

You could try springing your anchor rode, slightly.
See ➥ https://www.cruisersforum.com/forums....html#post2642

[Mr B]

You will be surprised at how much your laptop sucks out of the batterys,
I now run the diesel if Im using my laptop and no sun,
I cantilever my panels to get the morning sun, It whacks the power in, In the mornings,

[rgleason]

Sean do you have lifepo batteries for the boat now? What size?

[Pete7]

Originally Posted by rgleason

Sean do you have lifepo batteries for the boat now? What size?

Can't see him doing that. What with all that mining and destruction of Australia's deserts for the lithium. Then carted off to some sweatshop in China to be made in to LFP, just so some decadent yachtie in a first world country can have ice in their gin

I think Sean is more likely a Baghdad battery person, sort of strips of lead and copper immersed in lemon juice and charged by trailing and a home made prop connected to a old dynamo

Pete

[LittleWing77]

Originally Posted by Pete7

I think Sean is more likely a Baghdad battery person, sort of strips of lead and copper immersed in lemon juice and charged by trailing and a home made prop connected to a old dynamo

Guess again, Pete!

My understanding is that Sean built his own batteries.

He really is incredibly gifted, although I'm sure he doesn't think of himself that way.

He should be nominated for a McArthur Fellowship...
LW77

[LoudMusic]

Originally Posted by Tomodore

It is amazing how often the panels point badly. Yes use dead dinosaurs, in our case we have no generator so we run the engine in reverse at anchor and smile while 60 amps flow into our batteries. 8 years so far on this engine and 4000 hours. Figure 12 more years to 10,000 and rebuild, I’ll be 80 then and happy to rebuild or repower if I am still floating.

Why do you run it in reverse?

[rslifkin]

Depending on how the panels are placed and angled on the boat, direction may be a big issue or a small one. For me, the panels angle slightly forward and out, so boat facing south is ideal, but there's not a big difference if we're facing a less optimal direction. Plus, nothing on the boat shades my panels.

Realistically, the best answer is "add more panels". My 820w is plenty on a good sunny day, as we've got surplus power for quite a few hours in the afternoon, meaning the generator only gets run when needed, never just to charge batteries. However, on a cloudy day, I wouldn't mind having more.

A single cloudy day is fine, as the evening generator run for dinner will catch us up a bit (meaning we can get topped off the next day if it's sunny), but a bunch of cloudy days in a row would be a pain (haven't experienced that away from shore power yet since installing the solar). So eventually when I ditch the bimini for a hard top, I'll probably put another panel up there. We'll end up with a bigger surplus on good days, but on crappy days when we're only seeing 20% of an ideal harvest, we'll be closer to what we need.

As far as generator runtime, if you need to run it to supplement solar, plan to run it in the morning, as early as possible. That way the charger can dump current into the batteries while they're still low, requiring less runtime (and letting the solar finish charging).