Generators V running an engine

[Orca]

Some really good stuff in here so thanks but just to add in a couple of points if it helps with the advice.

 

We can heat our water independently of the engine (webasto) if we want too.

 

Our engine is a modern Isuzu unit and is surprisingly vibration free on tickover

 

Our charger is one of these

 

Mastervolt linky

 

 

I don't know your situation; whether you nominally have 240v hook-up in a boatyard or whatever; but I only really purchased my genny for when out on the Towpath for extended periods (as I sometimes do). For normal cruising I wouldn't have bothered; as never really in one place long enough to justify it. I also have six, 6 volt batts so the A/H capacity is quite good; though if on the towpath for up to 14 days then genny is defo justified. Good luck in your decision!

[Naughty Cal]

I dont fully understand why or how Narrowboatists manage to consume so much electricity that they need to have either the engine running or a genny rattling away on the towpath at least once every day. What is it you use that consumes so much power?

 

When our batteries were in good condition, (which sadly they are not any more but they are to be replaced this weekend) we could stay in the same place for three days without the need to fire up the engine at all. Narrowboatists during the same period seemed to be reliant on running their engines morning, noon and in some cases night. What do you do in there that needs so much electricity?

 

OK i understand that some narrowboats have high powered appliances such as washing machines etc. that need the engine running to create enough power to use them. But not every day surely.

[jenlyn]

I dont fully understand why or how Narrowboatists manage to consume so much electricity that they need to have either the engine running or a genny rattling away on the towpath at least once every day. What is it you use that consumes so much power?

 

When our batteries were in good condition, (which sadly they are not any more but they are to be replaced this weekend) we could stay in the same place for three days without the need to fire up the engine at all. Narrowboatists during the same period seemed to be reliant on running their engines morning, noon and in some cases night. What do you do in there that needs so much electricity?

 

OK i understand that some narrowboats have high powered appliances such as washing machines etc. that need the engine running to create enough power to use them. But not every day surely.

 

fridge freezer, tv, music, pc, washing machine, fancy lighting, various pumps, hoover etc etc, just like a house really. I wander how often you would need to recharge your house batts if you were not on the grid?

[blodger]

We both have the same!!! I find Webasto louder than my engine and it does not charge the engine. I have a Mastervolt Combi 12/2000 - 100 whatever that means!!

 

Looking at the Mastervolt specs I see its bulk charge rate is at 14.25v and there is no mention of a facility to equalise charge at a higher voltage.

 

I am no electrical expert but perhaps someone better qualified will comment but it seems to me that a small genny with a charger that will equalise would be an advantage from time to time for the sake of longevity of the batts?

[carlt]

I dont fully understand why or how Narrowboatists manage to consume so much electricity that they need to have either the engine running or a genny rattling away on the towpath at least once every day. What is it you use that consumes so much power?

 

When our batteries were in good condition, (which sadly they are not any more but they are to be replaced this weekend) we could stay in the same place for three days without the need to fire up the engine at all. Narrowboatists during the same period seemed to be reliant on running their engines morning, noon and in some cases night. What do you do in there that needs so much electricity?

 

OK i understand that some narrowboats have high powered appliances such as washing machines etc. that need the engine running to create enough power to use them. But not every day surely.

Staying in one place, for 3 days, without running your engine may well have shortened the life of your batteries. Not too serious, for a leisure boat, but a problem if those batteries are the replacement for the mains, in a home.

 

Also, bear in mind, if you had to run your batteries every 3 days, someone with 3 times the power consumption would have to run theirs every day.

 

Personally my power requirements were very small so I got away with about 400 watts of solar panels and one day a month, on the genny, to top up the batteries.

 

These days, though, people demand all the luxuries of a house which consume a huge amount of electricity.

[nb Innisfree]

We're stuck on the horns of this dilemma at the moment too. Apart from the safety issue and lack of tax breaks, a petrol generator means lugging lots of fuel down the towpath, so that's out. Diesel generators are big, heavy, noisy and expensive, whilst LPG generators require an awful lot of space for storing fuel cylinders.

 

For the moment, we're sticking with using the engine and getting hot water as a free bonus. We're a few feet short of 72', so considering building a platform off the back of the stern which could hold some LPG cylinders and a generator in a sound-proofed box.

 

Still not convinced though. A generator that can chuck out as many amps as an engine is not cheap - so we might be better off just wearing the engine out anyway. We put in a big enough battery bank that charging it over 80% wasn't necessary on a daily basis, so there's not much to be gained efficiency-wise.

 

Please keep the arguments coming. We have a decision to make!

 

As you are using a partial state of charging regime i.e. only going to 80% SoC, then you need to do a long absorption charge on a weekly basis. You can do this with the engine (and a charge controller if alt is an older type) or you can use a small digital genny and a charger that can be adjusted to any voltage you choose, this is what we do, a short daily bulk charge with the engine and a weekly absorption with a Kipor genny which is identical to a Honda EU20 and a third of the price, much more flexible and you have a backup if engine fails for any reason. I think this is the best compromise between battery and fuel costs. Before someone jumps in and says why don't you just cruise more, as retired full time liveaboards we don't need to be anywhere at a certain time and need to optimise our fuel consumption, therefore most of our charging is done whilst moored. Of course if we do an occasional long cruise of 8 hrs or more, very rare, then this can provide an absorption charge.

[Naughty Cal]

fridge freezer, tv, music, pc, washing machine, fancy lighting, various pumps, hoover etc etc, just like a house really. I wander how often you would need to recharge your house batts if you were not on the grid?

 

Do you think we live in a cave when afloat?

 

We have a fridge with a freezer compartment, we have a TV and stereo, we have lighting (which will be swapped for LED bulbs this weekend now they have finally arrived), we have various pumps and we have a vacuum cleaner and a small invertor capable of running the toaster or sandwich toaster bu mist importantly the electric blanket.

 

All of which manage with 2No. 85AH batteries for a few days.

 

Everytime you use your batteries you are reducing their lifespan. All boats have to at some point replace their battery bank. Personally i dont think ours have done too badly. They have lasted just over two years but in that time have been badly abused resulting in them being quite unreliable in the last few months. They are to be replaced at the weekend with a pair of 105AH Varta leisure batteries which will increase our capacity slightly. Im happy to spend £150 every couple of years to ensure we have a reliable source of power when away from our home mooring.

 

Narrowboats tend to have much bigger battery banks than we can ever expect to fit in our engine bay, yet still seem to be constantly having to run their engines. Something doesnt add up, or maybe narrowboatists are a strange lot that like to listen to the sound of a modern diesel engine grumbling away under the deck

[ymu]

If a 6hp honda genny gives you 2.8 kw, why run a 40 hp engine turning an alternator or two that put out the same or less amperage?

 

Unless -

 

Your getting your only source of hot water from the engine at the same time

Your engine/alternator pully set up is 2:1 so you run at 1500 rpm or less - less noise and fuel used

You have no room for the genny, no decent charger, etc

Your constantly mobile

Watt for watt, your engine is more efficient, but factor in, not only fuel but long term depreciation and replacement costs.

 

In all cases, belt and braces gives alternative opportunities and peace of mind

 

Quality of life is having freedom of choice.

A small genny as a back-up is a given, but our dilemma relates to what we do every day. We get through about 300ah/day (approx 180 litres/month diesel).

 

Hot water only from the engine and stove at the moment - stove not ideal in summer, obv. Haven't measured the pulley ratio, but seems to be 2:1 or thereabouts given the charging voltages we get - we charge at 1500-2000 rpm. Cruiser deck so there is some space for a genny (but not for additional LPG cylinders if we went that route). Not constantly mobile or it wouldn't be a problem we had to grapple with.

 

So far, the engine is winning hands down. The issue for us is how the cost of extra wear and tear on the engine stacks up against the cost of using a generator (on a daily basis). Generators also depreciate, get worn down, and need repairing; they cost a fair bit to buy in the first place if they're going to be any good as an alternative to using the engine; and if it's a petrol genny the fuel costs are 65% higher even before the additional efficiency of using the engine is taken into account (we're CCers on a 90/10 split, ~74p/litre at the moment).

 

So, should we stick with the engine as our main source of leccy on a daily basis, or is there a good argument to be made for a generator in our circumstances?

[Guest]

or you can use a small digital genny and a charger that can be adjusted to any voltage you choose,

 

Just for clarity here - do you mean a charger as in one that we would already have fitted to the boat or are you meaning something else over and above??

 

Sorry for the numty type question.

[ymu]

I dont fully understand why or how Narrowboatists manage to consume so much electricity that they need to have either the engine running or a genny rattling away on the towpath at least once every day. What is it you use that consumes so much power?

 

When our batteries were in good condition, (which sadly they are not any more but they are to be replaced this weekend) we could stay in the same place for three days without the need to fire up the engine at all. Narrowboatists during the same period seemed to be reliant on running their engines morning, noon and in some cases night. What do you do in there that needs so much electricity?

 

OK i understand that some narrowboats have high powered appliances such as washing machines etc. that need the engine running to create enough power to use them. But not every day surely.

TV, laptops and fridge are the only power hogs we have on the boat. But we work as well as live aboard, and that work involves the laptops, which are also our main source of entertainment. We use about 300ah/day. We'd need a 3000ah battery bank if it was to last 3 days, and then it would take us 15 hours to charge it up.

 

As you are using a partial state of charging regime i.e. only going to 80% SoC, then you need to do a long absorption charge on a weekly basis. You can do this with the engine (and a charge controller if alt is an older type) or you can use a small digital genny and a charger that can be adjusted to any voltage you choose, this is what we do, a short daily bulk charge with the engine and a weekly absorption with a Kipor genny which is identical to a Honda EU20 and a third of the price, much more flexible and you have a backup if engine fails for any reason. I think this is the best compromise between battery and fuel costs. Before someone jumps in and says why don't you just cruise more, as retired full time liveaboards we don't need to be anywhere at a certain time and need to optimise our fuel consumption, therefore most of our charging is done whilst moored. Of course if we do an occasional long cruise of 8 hrs or more, very rare, then this can provide an absorption charge.

Thanks, that's very helpful.

 

We got the battery management system and batteries from Adverc - they reckoned charging them to full once a month would be enough to keep them healthy. If once a week is more advisable, then that is a damn fine argument for a decent generator.

[jenlyn]

Do you think we live in a cave when afloat?

 

We have a fridge with a freezer compartment, we have a TV and stereo, we have lighting (which will be swapped for LED bulbs this weekend now they have finally arrived), we have various pumps and we have a vacuum cleaner and a small invertor capable of running the toaster or sandwich toaster bu mist importantly the electric blanket.

 

All of which manage with 2No. 85AH batteries for a few days.

 

Everytime you use your batteries you are reducing their lifespan. All boats have to at some point replace their battery bank. Personally i dont think ours have done too badly. They have lasted just over two years but in that time have been badly abused resulting in them being quite unreliable in the last few months. They are to be replaced at the weekend with a pair of 105AH Varta leisure batteries which will increase our capacity slightly. Im happy to spend £150 every couple of years to ensure we have a reliable source of power when away from our home mooring.

 

Narrowboats tend to have much bigger battery banks than we can ever expect to fit in our engine bay, yet still seem to be constantly having to run their engines. Something doesnt add up, or maybe narrowboatists are a strange lot that like to listen to the sound of a modern diesel engine grumbling away under the deck

 

sorry, but 2 85 amp batts running that lot for a "few days"? does'nt ring true to me

[nb Innisfree]

I dont fully understand why or how Narrowboatists manage to consume so much electricity that they need to have either the engine running or a genny rattling away on the towpath at least once every day. What is it you use that consumes so much power?

 

When our batteries were in good condition, (which sadly they are not any more but they are to be replaced this weekend) we could stay in the same place for three days without the need to fire up the engine at all. Narrowboatists during the same period seemed to be reliant on running their engines morning, noon and in some cases night. What do you do in there that needs so much electricity?

 

OK i understand that some narrowboats have high powered appliances such as washing machines etc. that need the engine running to create enough power to use them. But not every day surely.

 

Simple really, the average well equipped nb's or wb's use on average 125 to 175.1 ah per day or 1.5 to 2.1 kwh, this not excessive considering the average house uses somewhere around 7 or 8kwh. 150 ah needs a minimum of 1 hour bulk charging to replace assuming a large enough batt bank and alternator, this assumes newish batts in 1st class condition, but in reality with a smaller alt + the need to keep up a reasonable voltage with older and increasingly failing batts requires bulk + absorption charging which takes much longer. To go 3 days without any charge requires a min of 300 ah batt bank if you start from 1000% SoC and don't go below 50% SoC and have average consumption, this is only achievable if batts are new, as they get older the capacity drops requiring more charging or a increasingly bigger bank. Boats that use average power and need to charge morning noon and night have got knackered batts

.

 

TV, laptops and fridge are the only power hogs we have on the boat. But we work as well as live aboard, and that work involves the laptops, which are also our main source of entertainment. We use about 300ah/day. We'd need a 3000ah battery bank if it was to last 3 days, and then it would take us 15 hours to charge it up.

 

Thanks, that's very helpful.

 

We got the battery management system and batteries from Adverc - they reckoned charging them to full once a month would be enough to keep them healthy. If once a week is more advisable, then that is a damn fine argument for a decent generator.

 

Once a month is often quoted but in our experience this is far too long.

[Naughty Cal]

sorry, but 2 85 amp batts running that lot for a "few days"? does'nt ring true to me

 

We dont sit with the TV , radio, vaccum cleaner, all lights on, all pumps running, fridge door open, toaster constantly on whilst making an endless chain of toasted sandwiches and having the Webasto blasting out heat in the middle of the summer.

 

Its about understanding what power reserves you have and managing your power consumption. Our biggest power consumer during the summer is the fridge and during the winter is the heating. If we have the TV on we turn the lights off. Much as we do at home. If we fancy toast and we are a couple of days without running the engine or being plugged in we use the gas grill. I will tend to vacuum either when we have moved off to return to our home mooring or when we get back to the home mooring and are plugged in. Luckily our appliances are all modern low powered versions. The fridge for example is a very efficient compressor version by Engel that uses approx 1.5 amps per hour however doesnt run continuosly.

 

We are making inroads into reducing our power consumption further by replacing our halogen lighting with LED replacements. The cabin lights are to be done tomorrow night now the bulbs have finally arrived and the cockpit lighting when the bulbs arrive next week.

 

It seems modern narrowboats have all these high powered gadgets fitted yet simply dont have the power supplies to sustain themselves. Seems they are unfit for purpose if you are forced into running the engine to carry out simple tasks.

[Proper Job]

sorry, but 2 85 amp batts running that lot for a "few days"? does'nt ring true to me

I think she's forgotten to mention the 6 hours cruising a day

[nb Innisfree]

Just for clarity here - do you mean a charger as in one that we would already have fitted to the boat or are you meaning something else over and above??

 

Sorry for the numty type question.

 

I don't know what charger you have, I mean a charger that can be adjusted to provide an absorption and sometimes a float voltage ideally suited to whatever type of batts you have, some chargers though of the three stage variety have fixed voltages which is ok but to cater safely for all batts will prob have an absorption voltage slightly on the low side, occasionally an equalisation charge is beneficial which requires a very long charge or alternatively a shorter raised voltage one. We have a Victron charger which has a wide range of adjustable absorption and float voltages.

Edited November 11, 2010 by nb Innisfree

[Naughty Cal]

I think she's forgotten to mention the 6 hours cruising a day

 

Not at all. We enjoy cruising as much as possible but on occasion when we just cant be arsed we also enjoy spending a few days here and there chilling out and enjoying a few days break. It doesnt have to be far away either. The last time we spent a few days stationary was in Saxilby, about 35 minutes from our home mooring.

[cotswoldsman]

Not at all. We enjoy cruising as much as possible but on occasion when we just cant be arsed we also enjoy spending a few days here and there chilling out and enjoying a few days break. It doesnt have to be far away either. The last time we spent a few days stationary was in Saxilby, about 35 minutes from our home mooring.

 

Must knock Saxilby off my cruising plan!!

[jenlyn]

Just for clarity here - do you mean a charger as in one that we would already have fitted to the boat or are you meaning something else over and above??

 

Sorry for the numty type question.

 

we use a multi plus 3000-120 and a honda e20i, i run the genny on gas, it runs from 1700 to 1830 week days if i have not been moving, (i dont for some reason like the batts below 12 volts) on saturdays, i run the genny to float plus 2 hours. the cost at present for running the genny is a 13kg bottle per month(£21). I believe the bottle contains 25 litres of gas which equates to 84p per litre, so cheaper than petrol, and only a little more expensive than diesel, but i believe saves wear and tear on the engine

[cotswoldsman]

we use a multi plus 3000-120 and a honda e20i, i run the genny on gas, it runs from 1700 to 1830 week days if i have not been moving, (i dont for some reason like the batts below 12 volts) on saturdays, i run the genny to float plus 2 hours. the cost at present for running the genny is a 13kg bottle per month(£21). I believe the bottle contains 25 litres of gas which equates to 84p per litre, so cheaper than petrol, and only a little more expensive than diesel, but i believe saves wear and tear on the engine

 

 

Does that mean yours is bigger than mine??????

 

 

[Naughty Cal]

Must knock Saxilby off my cruising plan!!

 

I wouldnt visit the Fossdyke then. Its one of the few and by few I mean three highlights of this stretch.

[jenlyn]

Does that mean yours is bigger than mine??????

 

just asked OH to compare, she wont, has a headache

[Pretty Funked Up]

All of which manage with 2No. 85AH batteries for a few days.

 

I'd love to know the voltage your are at after a few days running what you mention. Doing the calculations, just your fridge would kill them in about 35hrs.

[jenlyn]

We dont sit with the TV , radio, vaccum cleaner, all lights on, all pumps running, fridge door open, toaster constantly on whilst making an endless chain of toasted sandwiches and having the Webasto blasting out heat in the middle of the summer.

 

Its about understanding what power reserves you have and managing your power consumption. Our biggest power consumer during the summer is the fridge and during the winter is the heating. If we have the TV on we turn the lights off. Much as we do at home. If we fancy toast and we are a couple of days without running the engine or being plugged in we use the gas grill. I will tend to vacuum either when we have moved off to return to our home mooring or when we get back to the home mooring and are plugged in. Luckily our appliances are all modern low powered versions. The fridge for example is a very efficient compressor version by Engel that uses approx 1.5 amps per hour however doesnt run continuosly.

 

We are making inroads into reducing our power consumption further by replacing our halogen lighting with LED replacements. The cabin lights are to be done tomorrow night now the bulbs have finally arrived and the cockpit lighting when the bulbs arrive next week.

 

It seems modern narrowboats have all these high powered gadgets fitted yet simply dont have the power supplies to sustain themselves. Seems they are unfit for purpose if you are forced into running the engine to carry out simple tasks.

 

woteva

[nb Innisfree]

Just for clarity here - do you mean a charger as in one that we would already have fitted to the boat or are you meaning something else over and above??

 

Sorry for the numty type question.

 

Sorry just noticed your post, can't say for definite if your charger is adjustable but I would think it is.

[jenlyn]

I'd love to know the voltage your are at after a few days running what you mention. Doing the calculations, just your fridge would kill them in about 35hrs.

 

she has modern appliances, seemingly we do not

i think one modern appliance may be sprouting from her ummmmm back end