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Post by Clinton Cool on Dec 1, 2018 9:35:22 GMT
Not sure how many off grid liveaboards there are on this site but thought it might be worth sharing tips on how to reduce electrical usage. If you're like me, hate running your engine, or genny in my case more than necessary, read on... The obvious ones are led lights, only having one light on blah blah.. Here are mine, which apply from around the middle of October until around the end of February. At other times I have plenty of solar, so don't need to bother: Do all of the following only when charging the batteries: Washing up (once a day for me) Have a shower If you're going to watch tv for a couple of hours, try to time this with charging the batteries, if possible. Charge your laptop/ phone/ power banks either when charging the batteries or when cruising. Fill 2 or 3 large bottles with water when charging your batteries. This will do you for brews for the day, save you needing to use your water pump. The idea with all the above is that most of the time when charging, less amps are going into the batteries than the generator and battery charger/ alternator can deliver. So, you are harvesting extra amps at very low cost, almost free! Also, it takes longer to put something back into the battery than to take out. You're avoiding taking it out with these measure, win win, what's not to like! No doubt someone will find a hole in my argument somewhere but I reckon overall it's a winner. Any more tips? Oh another one: if like me you have a t.v. that sits on standby (no on-off switch) you'll probably find it burns around 3 watts doing nothing. Do yourself a favour, flick your switch off at the fuse box at night, every bit makes a positive difference. I do most of these things except that I fill 3 large Tesco water bottles up with fresh drinking water at the CRT facility taps. I would always boil water from the boat tank before consumption. I have also switched to a 12v TV. It only draws about 1.5 amps when on. It seemed silly in the past having to convert 12v to 240v using a small inverter, then using the old TV’s power supply to step back down to 12v. Another big tip.. There is a lot of discussion about batteries, but if you have a poor connection between the batteries or charging circuit you might see a good charging voltage, but the amps might not be getting in as they should. I recently tightened them and changed one of my cables and it made a big difference. I also use a gas fridge. Ok I spend more on gas, but I’m pretty sure the cost outweighs the extra time you have have to run the engine when you’re not cruising and the cost of replacing batteries earlier. As the engine provides our hot domestic water, I run the engine for about 3 hours a day anyway (cruising or not). So the battery gets what it needs most days. I now use a single heavy duty car starter battery for domestic now. Iit’s enough for my daily demand and as I never connect to shore line, it lasts as long as when I had 4 expensive leisure batteries. Much cheaper and easier to carry! + 1 for gas fridge! Overall much better I think but having said that, Calor have increased their prices of late, I just paid over 34 quid for 13KG. Given that I used a bottle every 5 weeks it's starting to get expensive. My hot water comes from a Morco. I only wash up once a day as previously mentioned and showers, depending on social engagements, aren't always daily I hate running the engine to charge the batteries. Not only does it vibrate the whole boat but it seems wasteful to wear out a 5k lump for such a purpose. I found a nearly new Kipor generator on Ebay a couple of years ago for 150 quid. It's got that smart throttle facility whereby it only revs as high as the demand on it. Given that most of the time that demand is well below 10 amps I get 4 hours of running on 1 litre of petrol. Fuel is easy, siphon it straight out of the motor bike. The other advantage of the genny is that when I hook it up to the shoreline it makes the 240v system live so I can use the plug sockets to charge phones, power banks etc. The genny only weighs 8kg and sits on the back of my cruiser deck chained up with a cover over it. I have 375w of solar and a wind turbine. On average, in darkest winter, I need to run the genny for an hour and a half for 2 consecutive days then on the third day I'll run it for 3 hours, that will give a tail current of 1.5 amps into my single 105AH Trojan leisure battery. It all works pretty well, but happy to make further tweaks for further efficiencies!
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Post by Deleted on Dec 1, 2018 9:51:02 GMT
Sounds like you’ve got it pretty well sussed Ricco. It’s taken me 6 years to get to where I am! Looking back I cringe about the way I did some things then.
It is very interesting how many of those, who are totally off grid liveaboards, have sussed out that a single battery works well and is much cheaper than buying a bank of leisure batteries every 2 years. There was a lot of discussion about leisure batteries being re-branded starter batteries on the other forum years ago. I think it was a caravan club article where they cut a load open to investigate.
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Post by Deleted on Dec 1, 2018 10:30:33 GMT
One battery is the way to go.
Or two on separate circuits.
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Post by Deleted on Dec 1, 2018 10:34:08 GMT
One battery is the way to go. Or two on separate circuits. Well yes for engine start up and domestic circuit. Do you have 2 separate domestic circuits? That’s an interesting idea.
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Post by Clinton Cool on Dec 1, 2018 10:51:07 GMT
Sounds like you’ve got it pretty well sussed Ricco. It’s taken me 6 years to get to where I am! Looking back I cringe about the way I did some things then. It is very interesting how many of those, who are totally off grid liveaboards, have sussed out that a single battery works well and is much cheaper than buying a bank of leisure batteries every 2 years. There was a lot of discussion about leisure batteries being re-branded starter batteries on the other forum years ago. I think it was a caravan club article where they cut a load open to investigate. It will be 6 years for me in August. I started with 2 leisures and wrecked 2 sets of them. It took years for the penny to drop, I only use in the region of 25-30AH a day so why do I need 220AH of batteries? The answer of course is that I don't. So, when the time comes to throw away the Trojan it will just be the one, saving money, and time with interconnecting wiring etc. I spent a fair amount of time thinking about whether, given the same amount of discharge, it would take longer to fully charge a single battery or two. Eventually came to the conclusion that it makes no difference so, given that one battery costs half as much as two, provided your power usage isn't excessive, it makes no sense at all to have 2 leisure batteries.
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Post by Deleted on Dec 1, 2018 11:44:52 GMT
One battery is the way to go. Or two on separate circuits. Well yes for engine start up and domestic circuit. Do you have 2 separate domestic circuits? That’s an interesting idea. Not yet but I have an idea it would be worth fitting a forward battery charged by solar and wind for lights and device charging completely seperate from the domestic battery. OK so it would not be charged by engine but it removes the wind turbine to the front where the noise would be less of a problem (saloon area) and it also means one could live "low profile" on that battery by not using fridge or water pump. Solar panel to be on electric satellite dish mount for tracking (I have done this before) I've always been interested in this topic which is why I have retained an off grid vessel - I intend to live on this full time in future with no shore power or mooring. No intention to ever live anywhere else.. When I was off grid in the 90s and early 00s I had solar and wind and a small generator. Wind (aero gen 6) was very effective down the K&A near devizes and also around Leighton Buzzard on the GU. Been on a mooring for more years than I like due to kids at school but that will change one day !
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Post by thebfg on Dec 1, 2018 12:39:24 GMT
our tv and 12v socket at the front have their own battery.
it only gets used for the odd DVD when it's raining but it has a small inverter so all the phones and tablets get charged there other than that it's just the fridge that mainly uses the main bank.
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Post by Telemachus on Dec 1, 2018 14:35:25 GMT
LiFePO4 is the answer. Then you don’t have to worry about living like caveman and you can re-charge in an hour, every few days.
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Post by Deleted on Dec 1, 2018 15:35:25 GMT
Yes that's all very well but some people want to live like cavemen. Maaan.
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Post by Clinton Cool on Dec 1, 2018 15:54:24 GMT
LiFePO4 is the answer. Then you don’t have to worry about living like caveman and you can re-charge in an hour, every few days. What is this?
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Post by Deleted on Dec 1, 2018 16:01:36 GMT
Lithium (Li) Iron (Fe) Phosphate (Po4). The 4 should be in subscript.
Its wot they make golf trolley batteries from because people who do golf are risk averse and cash/debt rich.
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Post by Telemachus on Dec 2, 2018 10:19:10 GMT
LiFePO4 is the answer. Then you don’t have to worry about living like caveman and you can re-charge in an hour, every few days. What is this? If you have not been following the various debates then in summary They can take very high charge currents with that current barely tails off as full charge approaches, hence only an hour or so to charge provided you can supply enough current. they can be discharged to a very low SoC without damage They have no concept of “sulphation” so no issues with having to fully charge. In fact they prefer to be kept around mid-charge They have a very long cycle life. On the down side they are expensive and need a control system to prevent over charge or over discharge.
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Post by Clinton Cool on Dec 2, 2018 10:51:51 GMT
Oh, they are expensive, sack that then.
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Post by Deleted on Dec 2, 2018 11:06:42 GMT
I wonder if they will come down like PV (solar) did. I suppose not quite as much because part of the reason for cheap PV was subsidies.
Unless people start using home batteries which is an approach suggested by Tesla among others it seems the price will probably stay up. Lead mud weights will probably rule the roost for a while longer on canal boats with budget conscious owners.
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Post by Telemachus on Dec 2, 2018 11:41:38 GMT
Oh, they are expensive, sack that then. Expensive initially, yes. But very long life. And if you look at the whole-life cost for a mostly-static boat and factor in the massive reduction in engine or genny running time, the difference evaporates. Then you have the advantages of many fewer hours of nuisance from gennies or engines endlessly droning away.
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