Help understanding energy systems

[Mr.T]

Hi all. I’m at the early stages of planning for a new narrowboat to live aboard as a continuous cruiser. Just waiting for my property to sell before I can go ahead and buy one. Currently abit overwhelmed and confused at how the energy systems work onboard. I appreciate that this has probably been brought up many times before so apologies in advance. Any help or advice would be much appreciated.

From the research I’ve done already I would plan to have solar panels on the roof. Would I be correct in assuming that these would give me all if not most of the electricity I would need for around 6 months of the year? Is there an ideal number of panels? And is there a recommended/best brand for narrowboat live aboards? 
I would be looking at having lithium batteries, again is there an ideal number of these for efficiency? 
For the other 6 months, I’m assuming I would solely be relying on the diesel engine for charging the batteries? Approximately how long would the engine have to be running to fully charge the batteries? And any idea how long a good lithium battery set up typically lasts with general usage of electricity, 2-3 hours of tv, 15-30 minutes of electric cooking and a shower? Is it more a case of running the engine whilst all these are in use?

My final question is on stoves, I’m looking at getting a lockgate diesel stove with a back boiler and hot plate, supplying heat to two radiators. Do these stoves run off diesel from the engine? And how efficient are they if they’re left on day and night throughout winter? Do live aboards with these stoves find they use them for cooking during winter? 
Appreciate this is a long message so apologies for that, but any advice would be much appreciated. I should also mention that I’m not keen on having gas on board. I would be using an electric hob/steamer and air fryer for cooking.

[Eeyore]

Your principle problem appears to be in the first two sentences. There is a significant lead time for new boat builds. You could well find yourself looking for accommodation whilst the boat purchase process completes.

The power issue requires you to undertake a power audit to determine actual requirements. There are online resources to help with this, others will advise. 

[system 4-50]

While you wait for responses to come in, use the search function (which is now quite good) to browse.  There is oodles of good stuff on here.  Well worth spending a good few hours on it.

[Mr.T]

14 minutes ago, Eeyore said:

Your principle problem appears to be in the first two sentences. There is a significant lead time for new boat builds. You could well find yourself looking for accommodation whilst the boat purchase process completes.

The power issue requires you to undertake a power audit to determine actual requirements. There are online resources to help with this, others will advise. 

Luckily I’m able to move in with some family whilst the boat is being completed. It’s mainly to try and get my head around how the systems work and if what I’ve said  is correct and practical.

[Francis Herne]

The truly ideal amount of solar, if you're living on board year-round and using a variety of electric appliances, will always be more than you can actually fit on the roof of a narrowboat. Depends on the boat, but you can probably get enough panels to cover your energy demands through the summer.

 

There's a variety of good numbers and comments in this similar thread -- the tool @IanD linked to is particularly useful:

https://re.jrc.ec.europa.eu/pvg_tools/en/tools.html#api_5.2

Note that you'll need a big inverter to power all the stuff you mention, which will require a minimum number of batteries just to supply the necessary current within their rated limits.

 

Practicality of charging from the engine will depend on the size of your alternator(s). With a new-build you can specify quite a high-power alternator, older engines typically have much smaller alternators that will need many more hours running to produce the same amount of energy. They can be upgraded after the fact depending on the engine. Lithium helps a lot because you don't need the long, low-current tail charging required to properly charge lead-acid batteries.

 

Separate generators are an option, either standalone petrol ones or - much better, but much more expensive - small integrated diesel units.

 

Diesel stove will typically use fuel from your propulsion tank, but I know people with a separate tank. You can probably cook on them; I cook stuff on my wood-burner in the winter.

 

Hot water will come from waste heat from your engine, stove back boiler, or a separate diesel/gas water heater. Instant electric showers aren't practical due to the power draw; heating with an electric immersion coil can be an option in the summer but you won't have the power to spare year-round.

[Alan de Enfield]

1 hour ago, Mr.T said:

From the research I’ve done already I would plan to have solar panels on the roof. Would I be correct in assuming that these would give me all if not most of the electricity I would need for around 6 months of the year? Is there an ideal number of panels? And is there a recommended/best brand for narrowboat live aboards? 

 

If you were to cover the boat roof with solar panels, it may meet your demands for a couple of months per year, or it may meet your needs for 6 or 8 months of the year.

 

It totally depends on your 'demand'. The two extremes :

If you intend to live as you would in a house (with unlimited electricity) then you will be seriously dissapointed.

If you treat it as camping and only use it for led lights then you'll be happy.

 

If you are really planning on using you batteries for electric-cooking you are going to need to put a lot of work into planning your whole electrical generation and distribution system.

 

As has been said you really need to do a full electrical audit - a 'typical' boater may use 100Ah per day (you will probably use that in 30 minutes if using electric for your cooking.

To replace 100Ah per day you (if you have lead acid batteries) you will probably need to run the engine for 4 hours per day, and 8 hours at weekends to top them up properly.

Lithiums are a different story but cost is far higher and the knowledge and eqiupment to charge them is very different. You cannot just drop a lithium in place of a LA battery.

Edited August 9, 2023 by Alan de Enfield

[GUMPY]

Even with 4.3kW of panels a 3.6kW Hybrid inverter

And 11.6kWh of batteries 

I still find myself using mains electric in the winter.

Living as you would in a house is just not feasible in a NB.

Edited August 9, 2023 by GUMPY

[David Mack]

20 minutes ago, Francis Herne said:

Diesel stove will typically use fuel from your propulsion tank,

Or you can have a stove running on kerosene (domestic heating oil), which is much cheaper than diesel, but will need a separate tank. You may also need a tank large enough to take 500 litre deliveries as that is the minimum order for many domestic oil suppliers.

[robtheplod]

We have 800W solar fitted last Jan so yet to go through a full Winter, but so far its been enough for us........ be interesting to see when it tails off this autumn?

[Mr.T]

23 minutes ago, Alan de Enfield said:

 

If you were to cover the boat roof with solar panels, it may meet your demands for a couple of months per year, or it may meet your needs for 6 or 8 months of the year.

 

It totally depends on your 'demand'. The two extremes :

If you intend to live as you would in a house (with unlimited electricity) then you will be seriously dissapointed.

If you treat it as camping and only use it for led lights then you'll be happy.

 

If you are really planning on using you batteries for electric-cooking you are going to need to put a lot of work into planning your whole electrical generation and distribution system.

 

As has been said you really need to do a full electrical audit - a 'typical' boater may use 100Ah per day (you will probably use that in 30 minutes if using electric for your cooking.

To replace 100Ah per day you (if you have lead acid batteries) you will probably need to run the engine for 4 hours per day, and 8 hours at weekends to top them up properly.

Lithiums are a different story but cost is far higher and the knowledge and eqiupment to charge them is very different. You cannot just drop a lithium in place of a LA battery.

Is it a case of having the engine running whilst cooking or is it not as simple as that?

[Rob-M]

17 minutes ago, Mr.T said:

Is it a case of having the engine running whilst cooking or is it not as simple as that?

It's not as simple as that if you don't want to annoy other boaters.  The T&C's of the licence say you can only run an engine or generator between 8am and 8pm unless using the engine for propulsion.

[magnetman]

Having gas (13kg bottles) is -always- sensible on a narrow boat. 

 

 

[Alan de Enfield]

20 minutes ago, Mr.T said:

Is it a case of having the engine running whilst cooking or is it not as simple as that?

 

1 minute ago, Rob-M said:

It's not as simple as that if you don't want to annoy other boaters.  The T&C's of the licence say you can only run an engine or generator between 8am and 8pm unless using the engine for propulsion.

 

In addition your (say) 2kw electric oven will be drawing about 200 amps from your batteries, yes, running the engine (in the time periods allowed) would contribute to it but it would be unlikely to provide 100% of the demand.

Once you get above a 100amp alternator you are looking at special pulleys and belts to be able to take the load / strain.

[nicknorman]

16 minutes ago, Mr.T said:

Is it a case of having the engine running whilst cooking or is it not as simple as that?

Lithium batteries can be considered as a “bucket of electricity” - you can pour charge in and pour it out willy nilly. Unlike lead acid batteries which are quite sulky and won’t take charge quickly.

 

But the bucket still needs to have as much electricity put in as you take out! I don’t have any experience of solar but I do with lithium batteries and modern engines. We have a Beta 43, which has a 175A alternator so in theory can put 175Ah in an hour into lithium batteries. In practice if you try to do this the alternator will get very hot and have a short life, as well as putting a huge load on the engine at idle. To charge lithium with a big alternator you really need a proper alternator controller such as the wakespeed WS500 or the Mastervolt Alpha pro.

 

Many of your questions are “how long is a piece of string” so really difficult to answer - your power needs depend on what you switch on and for how long, and we can’t know that for you!

 

My main proposal to you would be not to go for a gas free boat. You don’t mention why you don’t want gas, but perhaps it is for safety reasons? The thing is, nearly all narrowboats have gas and they don’t blow up! People die from other causes like falling off in a tunnel or from a lock side, or most likely they die from non-canal-related causes. So gas free on grounds of safety isn’t really very logical.

 

The thing with live aboard, especially in winter, is that diversity /redundancy of things is really good. Because you can guarantee that the day the inverter or alternator packs up will be freezing cold, snowing, iced in or the like. By not having gas on the boat you have exposed yourself to single point failures that could spoil your day! On our boat we have a coal stove, diesel central heating, gas cooking, 3 engine alternators, one of which is a travelpower that can supply ac mains directly and is thus a backup to the inverter/charger. Our single point of failure for electricity is that there is only one engine but everything else is duplicated in some way or another. We do have an air fryer and don’t use the gas oven much, but it is there if we need it. Oh and we are not even live aboard!

[magnetman]

I think something people who are 'anti gas' fail to appreciate is that if you have a gas install on the boat (2 x 13kg bottles in locker and a cooker) you never actually have to use it if your electric cooking turns out to be fine anyway. You can turn the bottles off at the valve and leave them and nothing bad will ever happen. 

 

OK there is the space consideration I suppose but I would at the very minimum put a 2 burner gas hob in. Specially on a boat used for living on ! 

 

There are oil alternatives of course but you basically do want gas. 

 

 

[dmr]

Nobody yet has given you the standard bit of forum wisdom....why on earth are you trying to specify a boat, especially a liveaboard, when you know nothing about boats? Get a second hand one, learn about boats (and how to manage energy on a livaboard), and then specify the new boat if you still think you need one.

 

What is your intended boating? proper continuous cruising where you move often and explore the system, including rivers? almost static bridge hopping? moving up and down a short length of canal?

 

If you plan to move every few days in summer then solar is a bit less important and limiting access to the roof will sometimes be a problem etc etc

Its difficult to be gas free on a widebeam, and very difficult on a narrowboat. Making any sort of heat from batteries needs a lot of thought.

[Mr.T]

Thanks all, I didn’t know how important inverters and alternators were. I don’t think I’ll be using a lot of electricity, typical use would be something like 15-20 mins of air fryer and maybe one hob, 2-3 hours of tv or laptop use and a shower. And there would be washing machine use once or twice a week. But maybe this is considered a lot of use on a boat?

I’m not completely against having gas on board, would just rather it wasn’t there so it eliminates the obvious potential problems. But if it makes sense to have it on board then I’ll definitely consider it, thanks.

[Mr.T]

14 minutes ago, dmr said:

Nobody yet has given you the standard bit of forum wisdom....why on earth are you trying to specify a boat, especially a liveaboard, when you know nothing about boats? Get a second hand one, learn about boats (and how to manage energy on a livaboard), and then specify the new boat if you still think you need one.

 

What is your intended boating? proper continuous cruising where you move often and explore the system, including rivers? almost static bridge hopping? moving up and down a short length of canal?

 

If you plan to move every few days in summer then solar is a bit less important and limiting access to the roof will sometimes be a problem etc etc

Its difficult to be gas free on a widebeam, and very difficult on a narrowboat. Making any sort of heat from batteries needs a lot of thought.

Thanks for the advice, I did consider buying an older boat as a test but I didn’t like the idea of buying something that could potentially have a lot of underlying issues. So for me the idea of buying new sounds a lot safer. I’m not taking it lightly though, which is why I’m trying to learn as much as possible before committing. 
I plan to genuinely cruise in the summer months and then stay fairly local to where I live currently in the winter probably with a winter mooring.

[magnetman]

Out of interest have you spent a lot of time on narrow boats? Have you lived beside a public footpath before where people are inches from your windows? 

 

It can come as quite a shock if you are used to having some space around you. I lived on narrow boats for 12 yars continuously which was enough and I now have wider boats although they have less overall space than a good sized nb. There is something 'heavy' about the living space in a narrow boat. 

 

Also do you intend to live on the boat 'forever'? My mum got all enthusiastic about living on a narrow boat and she did it for over a decade having sold her property interests. Then later in life she found herself needing to return to land housing. Of course all she could afford was a tiny little flat when previously we had a nice house.

 

Property ownership is hassle but it is also security. You won't get basic fundamental security on a boat tied to a public towpath. It won't happen..

 

Boats are great, I have always lived on boats and always will but jumping in at the deep end is very risky. 

 

Good luck with it - just a little reminder of reality. 

 

Also fit gas on the boat ! 

 

[Peanut]

It is often suggested, that if you don't have much experience of boats, then It is good to hire one for a week or two to get some idea of what it is going to be like. Some say do it in the winter when it is cold, wet and the sun doesn't shine. That way you wouldn't be buying a used boat with issues.

Edited August 9, 2023 by Peanut
auto correct

[system 4-50]

A fundamental element of designing a gas narrowboat is where the gas bottles go, for maximum ease of replacement.

[magnetman]

Bow gas locker is usually ok. If the intention is to not use it then the gas will last a long time !

[MtB]

5 minutes ago, magnetman said:

Bow gas locker is usually ok. If the intention is to not use it then the gas will last a long time !

 

Not if you get a deck board and cratch cover. 13kg bottles in a bow locker become a right pain to live with and change.

 

Secondly, get as much solar as you can fit. I've never heard a boater say "I have too much solar, I'm thinking of getting rid of some of the panels." 

 

Finally congrats on electing to get a narrowboat. 95% of newbies seem to go for a fat bustud these days, out of sheer ignorance. 

 

 

P.S. yo keep mentioning a shower when thelectrics are being discussed. Please tell us you aren't planning an electric shower...

[Lady M]

41 minutes ago, Mr.T said:

Thanks for the advice, I did consider buying an older boat as a test but I didn’t like the idea of buying something that could potentially have a lot of underlying issues. So for me the idea of buying new sounds a lot safer. I’m not taking it lightly though, which is why I’m trying to learn as much as possible before committing. 
I plan to genuinely cruise in the summer months and then stay fairly local to where I live currently in the winter probably with a winter mooring.

I had more problems with my brand new boat than I did with one of my second hand purchases.

[system 4-50]

18 minutes ago, magnetman said:

Bow gas locker is usually ok. If the intention is to not use it then the gas will last a long time !

I disagree strongly.  Bow lockers for gas are a pain.