Power Saving Tips

[nb Innisfree]

Out of curiosity, why, please ?

 

Isn't that how the average modern vehicle aims to operate - nearly all power needs are met directly by the alternator, and only a small amount of discharging of the battery actually ever takes place - it is largely near 100% charged, for most of the time.

 

I changed a car battery a year or two back that had had 10 years of continuous service, and no firm evidence it wasn't going to give a bit more.

 

Dedicated boat starter batteries that get discharged only small amounts seem to last far longer than even well looked after "domestics", in my experience.

 

I am quoting Gibbo on this in one of his posts (wish he would make an appearance), apparently for some unknown reason batteries don't like having too shallow a discharge i.e. 5%. Car batts are discharged very little when starting (somewhere in the region of 0.25%?) which has little effect on it's longevity + as you say when running alternator keeps it up to 100%

 

Of course this assumes car starts on the button, I bet if it needs a lot of cranking over a prolonged period i.e. discharged by a few % battery life will be seriously reduced.

 

Edited to make more sense.

Edited January 22, 2010 by nb Innisfree

[Gibbo]

Out of curiosity, why, please ?

 

Isn't that how the average modern vehicle aims to operate - nearly all power needs are met directly by the alternator, and only a small amount of discharging of the battery actually ever takes place - it is largely near 100% charged, for most of the time.

 

I changed a car battery a year or two back that had had 10 years of continuous service, and no firm evidence it wasn't going to give a bit more.

 

Dedicated boat starter batteries that get discharged only small amounts seem to last far longer than even well looked after "domestics", in my experience.

 

Good question. I've just been trying to find an on line reference but can't come across any.

 

Here's the problem:

 

Shallow discharges at very low currents (say discharging a 100Ahr battery from 100% to 98% at 1 amp) causes the sulfate to build up in a slightly irregular way instead of evenly over all the plates. When charging is commenced this bit has a higher resistance (because the sulfate is a worse conductor than acid in contact with lead) so the actual bit that needs charging most (the sulfate) doesn't charge properly. It gets missed and the rest of the battery charges. This sounds daft but it is indeed what happens. A few cycles of this and that sulfate hardens. Basically because the charge cycle doesn't last long enough to get rid of it.

 

If the discharge is taken to a much lower level, the charge cycle lasts much longer and the sulfate is returned to the electrolyte.

 

Note that this only applies in the case of "intelligent" chargers. With a dumb charger or a normal alternator it carries on charging at high voltage no matter what the SoC of the battery. A smart charger goes into float early.

 

So the problem doesn't crop up on cars because they don't have clever chargers.

 

It is also doubtful that the very heavy discharge of starting the engine even causes the uneven sulfate build up in the first place. So it might not even happen with that type of use. I never found any firm references to this and could never come to any firm conclusions from our own tests so this final part is really just speculation. But educated speculation.

 

But there is absolutely no question whatsoever that continual very small discharges does indeed wreck batteries. Either don't discharge them at all, or make sure they go below 90% (really so the charge cycle lasts longer). The more accurate solution would be by all means make very small discharges, but make sure the charge cycle lasts at least 3 or 4 hours. This won't happen with a smart charger, it will go into float after a very short time.

 

Edit: PS, the problem is even worse with those stupid "adaptive charging" chargers because they go into float even earlier and short acceptance times is one of the biggest problems already without making it worse!

Edited March 18, 2010 by Gibbo

[smileypete]

Out of curiosity, why, please ?

 

Isn't that how the average modern vehicle aims to operate - nearly all power needs are met directly by the alternator, and only a small amount of discharging of the battery actually ever takes place - it is largely near 100% charged, for most of the time.

 

I changed a car battery a year or two back that had had 10 years of continuous service, and no firm evidence it wasn't going to give a bit more.

 

Dedicated boat starter batteries that get discharged only small amounts seem to last far longer than even well looked after "domestics", in my experience.

Here's another take on it.

 

Shallow cycling of open/flooded batteries may cause or contribute to a phenomenom called stratification, for more info see: (clicky) (clicky). It may also be caused by putting the battery on a surface colder than the ambient temperature. (clicky)

 

To mix up the electrolyte and reverse it I'd expect any one of the following should do.

 

Charging so the battery is gassing freely.

A decent bulk charge current to warm the battery some.

A reasonable amount of physical motion.

 

Since a car battery gets MUCH more movement than a typical narrowboat battery , I reckon this is why they cope with shallow cycling much better.

 

So, as long as an open/flooded battery gets FULLY charged, AND there's something to reverse any stratification, I think it should cope with shallow cycling just fine.

 

BTW I think stratification may have been the problem Rich had on the other thread.

 

cheers,

Pete.

[Gibbo]

Here's another take on it.

 

Shallow cycling of open/flooded batteries may cause or contribute to a phenomenom called stratification, for more info see: (clicky) (clicky). It may also be caused by putting the battery on a surface colder than the ambient temperature. (clicky)

 

To mix up the electrolyte and reverse it I'd expect any one of the following should do.

 

Charging so the battery is gassing freely.

A decent bulk charge current to warm the battery some.

A reasonable amount of physical motion.

 

Since a car battery gets MUCH more movement than a typical narrowboat battery , I reckon this is why they cope with shallow cycling much better.

 

So, as long as an open/flooded battery gets FULLY charged, AND there's something to reverse any stratification, I think it should cope with shallow cycling just fine.

 

BTW I think stratification may have been the problem Rich had on the other thread.

 

cheers,

Pete.

 

Nice one. I hadn't really considered stratification in this regard. It certainly could (in fact probably does) account for a good part of the problem. But definitely not all of it. I know this from the condition of the batteries I took apart after shallow cycling them!

 

But as I say it almost certainly will be a contributing factor.

[smileypete]

Nice one. I hadn't really considered stratification in this regard. It certainly could (in fact probably does) account for a good part of the problem. But definitely not all of it. I know this from the condition of the batteries I took apart after shallow cycling them!

 

But as I say it almost certainly will be a contributing factor.

Let me guess, sulphation? If so I'm not surprised.

 

cheers,

Pete.

[Gibbo]

Let me guess, sulphation? If so I'm not surprised.

 

cheers,

Pete.

 

Yes but only in tiny little patches.

 

Great big lumps of hardened sulfate in small spots, but clear plates in other areas. Very odd.

[smileypete]

Yes but only in tiny little patches.

 

Great big lumps of hardened sulfate in small spots, but clear plates in other areas. Very odd.

Did you try a good desulphator?

 

(Half) joking aside, I've found it takes up to 48 hours to recharge fully after a shallow cycle...

 

I have a fairly old battery with high self discharge that's not in use.

 

Recharging at C/400 for 24 hours in 7 days didn't maintain SoC and started to sulphate despite being well over the amount of charge lost.

 

So I now recharge 48 hours in 7 days which works nicely. It also gets 2 x 1 hour of C/40 during those 48 hours to deal with any stratification.

 

Going back to desulphators, they may or may not help with what you saw or what I found, BUT won't deal with stratification.

 

Best I can recommend for liveaboards with batteries on a charger 24/7 is to let the battery discharge to 25-40% every week or two, then recharge properly, then equalise if possible.

 

cheers,

Pete.

Edited March 23, 2010 by smileypete

[nb Innisfree]

Did you try a good desulphator?

 

(Half) joking aside, I've found it takes up to 48 hours to recharge fully after a shallow cycle...

 

I have a fairly old battery with high self discharge that's not in use.

 

Recharging at C/400 for 24 hours in 7 days didn't maintain SoC and started to sulphate despite being well over the amount of charge lost.

 

So I now recharge 48 hours in 7 days which works nicely. It also gets 2 x 1 hour of C/40 during those 48 hours to deal with any stratification.

 

Going back to desulphators, they may or may not help with what you saw or what I found, BUT won't deal with stratification.

 

Best I can recommend for liveaboards with batteries on a charger 24/7 is to let the battery discharge to 25-40% every week or two, then recharge properly, then equalise if possible.

 

cheers,

Pete.

 

 

Maybe a regular S.G. check will help with stratification by thoroughly mixing electrolyte with a hydrometer? in fact drawing electrolyte in and out of hydrometer several times before taking a reading will ensure more accuracy anyway?

Edited March 23, 2010 by nb Innisfree

[Pete of Ebor]

<rant>

 

Oh how i detest those lights with a passion. It is only by a thin thread of civilisation that I resist throwing every single one into the canal.

 

Are you scared of the dark? One of the loveliest things about the towpath at night is its true dark.

 

And then people stick these silly useless led lights outside their boats, no use to them but true pollution to me.

 

</rant>

Especially the ones that change colour, thank god they don't play musak.

 

Well that's done it now ! someone will go and invent one !

Edited October 17, 2010 by Pete of Ebor

[Peter Underwood]

We have 320 watts of solar and can run for two weeks at a time with no engine input in summer, despite having to run poer hungry CPAP breathing machine eight hours a night. Reckon the 800 pounds it cost will be repaid in 2-3 years and the panels are good for 20.

[Minos]

We have 320 watts of solar and can run for two weeks at a time with no engine input in summer, despite having to run poer hungry CPAP breathing machine eight hours a night. Reckon the 800 pounds it cost will be repaid in 2-3 years and the panels are good for 20.

What do you do for hot water?

[12uthy]

Just nicked this link from another thread, hope you don't mind carlt

mrd's stove

[bizzard]

Yes, but gas is often much easier to replace than electricity.

Gas fridge every time. Also chuck freezers out,most people shop for fresh food every 2,3 days.Its highly debatable whether or not its cheaper to buy

frozen grub or have a freezer running 24/7 and caning the batteries. bizzard.

Also use good,old tee shirts as cushion covers by cutting off the arms and sewing the arm and neck holes up.They also make good pillow cases,in view of the silly cost of anything upholstery. Another wheeze.repair busted trainer uppers with silicone sealant,but clean area with ex white spirit first.

Thats it for now folks,i'm wasting all me laptop batteries.

regards bizzard.

[bizzard]

You asked for it!

Eat plenty of carrots preferably raw,and so improve your eyesight. (Result) less lights on at night and none at all if a good moon with curtains open.Submarine crews eat loads of em in WW2 to see better when surfacing at night in enemy waters, to charge batteries from main engines.

bizzard.

[bizzard]

You asked for it!

Its me again,blow the laptop power i'm using up,so.

Always buy wind up clocks and watches,those wretched batteries cost a bomb.Mind you take into account the wee bit of extra food intake to provide the atrength to do so.I think you'll save a bit by winding em though.

regards bizzard.

[Caprifool]

I tend to eat less when living without clocks. I don't go "Oh, it's xxxx o clock! Time to eat" as often. Same with thermometers. It's surprising how cold it can get before freezing if you don't know the actual temperature.

[bizzard]

I tend to eat less when living without clocks. I don't go "Oh, it's xxxx o clock! Time to eat" as often. Same with thermometers. It's surprising how cold it can get before freezing if you don't know the actual temperature.

Perfectly true.People seem to spend an awful amount of time monitoring things. It seems most are using so much of all this ie gauges,flashing led lights,warning bleepers ect it all consumes power,those poor poor old batteries,they're giving themselves such a hard time,trying to run far too much equipment,all from the ancient invention ''the battery''.I think they're masochists and seem to enjoy it all,from what i can gather from post on the forum and my own experience doing repairs for people,having spent bombs of money on electrical appliances and gizzmo's they're now in denial as i never get replies to my rants.

Also there's loads of suppliers and electricians having an absolute field day out there.

I have a feeling your much more sensible about power usage than most Caprfool. I REPEAT AGAIN MOST OF YOU BOATERS OUT THERE,KEEP YOUR ELECTRICAL POWER REQUIREMENT DEAD SIMPLE.

[bizzard]

No I didn't. you tiresome woman.

 

You made a claim that I only argued things where I could quote regulations and that I walked away from arguments where I couldn't back my position with the law.

 

In this case, an assertion has been made that s10, Theft Act 1968 legitimises taking stuff out of skips. I have posted the text to show that it does not.

 

Perhaps it would be better for me to simply have asserted that it was untrue, then we could argue it back and forth for days.

I heard somewhere that once rubbish is put into a skip it then becomes the skip owners property,therefor stealing from them.

Pray correct me if i'm wrong,don't want an argument .

bizzard.

[NB Alnwick]

Eat plenty of carrots preferably raw,and so improve your eyesight. (Result) less lights on at night and none at all if a good moon with curtains open.Submarine crews eat loads of em in WW2 to see better when surfacing at night in enemy waters, to charge batteries from main engines.

bizzard.

 

Not entirely correct - the business about 'eating carrots' was an MI8/9 misinformation story intended to convince the enemy that British anti-submarine forces (Navy and Air force) had developed night vision through a special diet. The story was intended to explain the high proportion of successful strikes on enemy submarines (often on the surface at night) and the ships or tenders that supplied them.

 

The truth was that British Intelligence had captured an 'Enigma' machine with its associated code books and were, therefore, able to decipher enemy wireless messages which occasionally gave a fair indication of the enemy's location. The Germans did not know this and swallowed the 'Carrots' story - even to the extent of growing large quantities of carrots to feed to their own sailors and airmen . . .

[carlt]

The Germans did not know this and swallowed the 'Carrots' story - even to the extent of growing large quantities of carrots to feed to their own sailors and airmen . . .

Yeah, but....please tell me it's true that spinach made Popeye super strong

[bizzard]

Not entirely correct - the business about 'eating carrots' was an MI8/9 misinformation story intended to convince the enemy that British anti-submarine forces (Navy and Air force) had developed night vision through a special diet. The story was intended to explain the high proportion of successful strikes on enemy submarines (often on the surface at night) and the ships or tenders that supplied them.

 

The truth was that British Intelligence had captured an 'Enigma' machine with its associated code books and were, therefore, able to decipher enemy wireless messages which occasionally gave a fair indication of the enemy's location. The Germans did not know this and swallowed the 'Carrots' story - even to the extent of growing large quantities of carrots to feed to their own sailors and airmen . . .

Your probably right about the propaganda put out.

I once had a next door neighbor Mr Lucas who was a submariner during ww2 and he told me that the officers that went up top as soon as the boat surfaced were given extra portions of carrots for that purpose.

And my mum always tried to make us eat more of them and she new nothing whatsoever of what went on in any of the forces.And you can't argue with mum when your a kid. bizzard.

[Caprifool]

I have a feeling your much more sensible about power usage than most Caprfool.

 

Maybe so That reminds me of a question i have. How do you in the UK pay for your electricity in houses and apartments? I meen, per kw/h or fixed rate? And if in kw/h, what's the average going rate?

[carlt]

Maybe so That reminds me of a question i have. How do you in the UK pay for your electricity in houses and apartments? I meen, per kw/h or fixed rate? And if in kw/h, what's the average going rate?

The equations that UK power companies use to calculate electricity and gas charges were first devised by Stephen Hawkins.

 

I had a blazing row, with EDF, some time back, about them overcharging me and the guy on the phone refunded me because he didn't understand the maths.

[Caprifool]

The equations that UK power companies use to calculate electricity and gas charges were first devised by Stephen Hawkins.

 

So THATS why no ordinary person have been able to give a straight answer!

[Justme]

Elec billing is easy.

 

Your meter reads how many kWh (but they call it a unit) you use & they then times that by the cost per unit. An average price for someone on a standard rate would be in the 10-15p per kWh range. You can get some that charge more per unit with no standing charge. Some get charged more for the first X unit per billing period & then a lower rate for the rest. Some rates allow off peak at a cheaper rate but charge more for day time. But its all still easy to work out.

 

Gas is charged by the kWh too but they have to use a conversion factor to convert the volume of gas that is metered (unit gain) by its calorific value (which changes due to the quality of the gas) to get kWh which is then multiplied by the kWh price.