lead acid vs lithium batteries and solar usage

[Zen]

Hi all,

 

I've done a few searches on this forum but cant find the answer I'm after, if there is a thread on this already, I apologise and please point me to it....

 

I'm a complete newbie looking at getting a narrowboat in the near-ish future.  I'm in the research stage at the moment and having "fun" realising how different boat electrics are to house electrics. This has led me to Lithium Iron batteries and solar power.

 

From what I can tell: Most people have 3 x 110aH 12V lead acid batteries for leisure use, since Lead acid batteries do not like to go below 50% charge, the total usable capacity is 165aH or 1.98KWH. From late spring to early autumn the batteries are often charged from solar arrays ranging from 300W to 1.5KW using an MPPT charge controller plus any alternator charge from when boat is in motion. In the winter the batteries are topped up 1hr in the morning and 1hr in the evening via boat engine and alternator due to little or no light. I'm assuming that gas is used for central heating and cooking in these situation (or natural/fossil fuels).

 

I believe there is a lot of solar power lost in the summer months due to the charging cycle of Lead acid batteries in that they can only "fast charge" to 70% and the battery is already at 50%  on its lowest allowed point, then it is a top up charge followed by a floating charge at this point almost no solar energy is being stored.

 

So...

 

My theory is that, upfront costs aside, would it be better to have larger capacity Lithium Iron batteries  partnered with a larger solar array that could capture more power and use the additional power for heating / cooking. I am thinking of starting with an insane amount of leisure battery ~ 15KWH and 4.5KW solar array partly because I plan to go electric motor in the future and partly I want to minimise ongoing costs (yes I know batteries and pv panels will need to be replaced but the batteries I have in mind can do 8k deep cycles so monthly save for replacement will be low).

 

What I would like from you lovely people:

 

I would be most grateful if you could share with me

1.  Your battery setup as it is

2. The solar set up (if any) that you have

3. For each season Your ave daily energy use if known or a rough account of what power items you use 

4. For each season Any supplementary battery charging you do, e.g. 2hr engine running, generator, plug to grid

5.  Whether or not you have run out of power if so when and the repercussions of it.

6. anything else you may feel relevant,

 

thank you all for your input

regards

 

Zen

[Tony Brooks]

31 minutes ago, Zen said:

My theory is that, upfront costs aside, would it be better to have larger capacity Lithium Iron batteries  partnered with a larger solar array that could capture more power and use the additional power for heating / cooking. I am thinking of starting with an insane amount of leisure battery ~ 15KWH and 4.5KW solar array partly because I plan to go electric motor in the future and partly I want to minimise ongoing costs (yes I know batteries and pv panels will need to be replaced but the batteries I have in mind can do 8k deep cycles so monthly save for replacement will be low).

 

 

Remember that the amount of solar you can get on the roof of a narrowboat is limited by the smaller roof area, so be very careful. I doubt solar will cover electric heating and cooking for much, if any, of the year. If you want that, plus eventual electric boating, I think that you will need a decent generator.

 

34 minutes ago, Zen said:

3. For each season Your ave daily energy use if known or a rough account of what power items you use 

 

@IanD posted real world data logged solar delivery, but he also has a cocooned generator fitted. His boat was far from cheap because he made sure it would all work reliably. He or @nicknorman may have data logged consumption figures, but Nick's boat, I think, does not use electricity for heating and cooking.

 

I would sugest the vast majority of members do not have all electric boats, most use other forms of cooking and heating - for good reason.

I think everyone's electrical use is different, what is generally recommended is that you list all the electrical items you intend to sue, their consumption and then how long they will be used for between charging periods. That will allow you to work out how many Ah or Wh of consumption you are likely to have.  Using a toaster or microwave has a rather different consumption to using a full electric oven and hob.

[David Mack]

50 minutes ago, Zen said:

I'm assuming that gas is used for central heating and cooking in these situation (or natural/fossil fuels).

Gas for cooking. Space heating is usually provided by a diesel fired boiler and radiators or a solid fuel stove. Gas fired boilers used to be more common, but are very expensive to run compared with diesel or solid fuel.

[IanD]

1 hour ago, Tony Brooks said:

 

Remember that the amount of solar you can get on the roof of a narrowboat is limited by the smaller roof area, so be very careful. I doubt solar will cover electric heating and cooking for much, if any, of the year. If you want that, plus eventual electric boating, I think that you will need a decent generator.

 

 

@IanD posted real world data logged solar delivery, but he also has a cocooned generator fitted. His boat was far from cheap because he made sure it would all work reliably. He or @nicknorman may have data logged consumption figures, but Nick's boat, I think, does not use electricity for heating and cooking.

 

I would sugest the vast majority of members do not have all electric boats, most use other forms of cooking and heating - for good reason.

 

There's no way you'll get 4.5kWh of solar onto a narrowboat, there simply isn't enough space. I have a 60' boat with most of the roof covered in solar and that's 2.1kWh.

 

The solar yield calculators predict about 7kWh/day average in summer, and that's what I see if moored unshaded -- this varies from 4kWh/day to 10kWh/day depending on the weather. In winter it would be far less than this, less than 2kWh/day. This is what I see when moored in the marina.

 

But this is not the case for a boat moving around where you're not always unshaded either while cruising or when moored. The best yield I saw for a week in June was 4kWh/day, only about 60% of predicted -- and the lowest for a week in October was 1.9kWh/day, 90% of the predicted 2.1kWh/day -- shading loss is less in winter since there's much less direct sun. Average over the year (with terrible weather!) was 3.2kWh/day, 70% of the predicted 4.6kWh.

 

My boat is all-electric including cooking, which is fine because though this takes significant power it's much smaller (about a third) than that needed for (electric) propulsion -- which is why I have a 35kWh 48V battery and 10kVA inverter/charger, so there's no added cost for electric cooking. Domestic power use per day over the year averaged out at 3.7kWh/day, depending on amount of cooking and washing (washer/drier on board) it ranged from 2kWh/day to 6kWh/day.

 

Note that solar power even in summer was not much bigger than domestic power use, though for sure the weather contributed to this -- but also the fact that solar yield when cruising (including at various moorings) was only about 60% of that predicted when moored in the marina in the full sun, because you're sometimes in the shade.

 

Electric cooking only really makes sense on a hybrid boat, where the electrics/battery/inverter needed to support it are already there for electric propulsion -- which in my case*** accounted for about three-quarters of total energy demand, domestic use was about a quarter. For a diesel boat, gas for cooking/kettle makes far more sense.

 

***this was cruising for an *average* of 5 hours per day while on board, which I suspect is a *lot* more than most boaters do... 😉 

Edited October 8 by IanD

[TheBiscuits]

48 minutes ago, IanD said:

***this was cruising for an *average* of 5 hours per day while on board, which I suspect is a *lot* more than most boaters do... 😉 

 

Ah, but does it suit you? 🤣

[IanD]

4 minutes ago, TheBiscuits said:

 

Ah, but does it suit you? 🤣

You missed off the "sir"... 😉 

 

I just meant that this explains why my energy use for propulsion is high (3x domestic use), other boaters may use rather less if they cruise for fewer hours per day -- especially if they go more slowly, like some certainly do... 😉 

Edited October 8 by IanD

[blackrose]

1 hour ago, IanD said:

There's no way you'll get 4.5kWh of solar onto a narrowboat, there simply isn't enough space. I have a 60' boat with most of the roof covered in solar and that's 2.1kWh.

 

Do you mean there's no way he'll get 4.5kW of solar panels onto a narrow boat and you have 2.1kW?

[Tony Brooks]

Maybe he has seen the narrowboat that we saw in the Macc. maybe 10 years ago. Two talk masts with three (I think) cross trees with solar panels hanging from them, plus panels hanging all down the side from the handrails. I would not like to try to get that lot facing the sun, especially as the ones on the masts were at 90 degrees to the ones on the side and they would have shaded at least some of the roof panels.

[bizzard]

Grow Sunflowers and hang small solar panels on em and they will face the sun automatically.

[nicknorman]

3 hours ago, Zen said:

Hi all,

 

I've done a few searches on this forum but cant find the answer I'm after, if there is a thread on this already, I apologise and please point me to it....

 

I'm a complete newbie looking at getting a narrowboat in the near-ish future.  I'm in the research stage at the moment and having "fun" realising how different boat electrics are to house electrics. This has led me to Lithium Iron batteries and solar power.

 

From what I can tell: Most people have 3 x 110aH 12V lead acid batteries for leisure use, since Lead acid batteries do not like to go below 50% charge, the total usable capacity is 165aH or 1.98KWH. From late spring to early autumn the batteries are often charged from solar arrays ranging from 300W to 1.5KW using an MPPT charge controller plus any alternator charge from when boat is in motion. In the winter the batteries are topped up 1hr in the morning and 1hr in the evening via boat engine and alternator due to little or no light. I'm assuming that gas is used for central heating and cooking in these situation (or natural/fossil fuels).

 

I believe there is a lot of solar power lost in the summer months due to the charging cycle of Lead acid batteries in that they can only "fast charge" to 70% and the battery is already at 50%  on its lowest allowed point, then it is a top up charge followed by a floating charge at this point almost no solar energy is being stored.

 

So...

 

My theory is that, upfront costs aside, would it be better to have larger capacity Lithium Iron batteries  partnered with a larger solar array that could capture more power and use the additional power for heating / cooking. I am thinking of starting with an insane amount of leisure battery ~ 15KWH and 4.5KW solar array partly because I plan to go electric motor in the future and partly I want to minimise ongoing costs (yes I know batteries and pv panels will need to be replaced but the batteries I have in mind can do 8k deep cycles so monthly save for replacement will be low).

 

What I would like from you lovely people:

 

I would be most grateful if you could share with me

1.  Your battery setup as it is

2. The solar set up (if any) that you have

3. For each season Your ave daily energy use if known or a rough account of what power items you use 

4. For each season Any supplementary battery charging you do, e.g. 2hr engine running, generator, plug to grid

5.  Whether or not you have run out of power if so when and the repercussions of it.

6. anything else you may feel relevant,

 

thank you all for your input

regards

 

Zen

We are just a holiday boat but we have about 7kWh of Li batteries. No solar though. We are fairly profligate with the power, electric kettle and air fryer (we hardly ever use the gas oven these days) but we have a gas hob. We sometimes run the washing machine from the batteries and even the immersion heater😱. We have a decent alternator and travelpower which means we can charge at about 200A(12v system). We use around 200-250Ah a day (say 2.5 to 3.25 kWh)
 

Lithium batteries are fantastic, just a bucket full of electricity that you can pour electricity in and out of. Unlike lead acid which is sulky, grumpy and resistant to doing anything much! But a proper Li battery installation is expensive and technically complex to get right.

 

With a roof full of solar you will have enough power in the summer. You don’t need heating in the summer! You do need heating in the winter but the solar will be pants, so you will definitely want a solid fuel or diesel stove (gas heating is too expensive).

Edited October 8 by nicknorman

[David Mack]

2 hours ago, IanD said:

 

There's no way you'll get 4.5kWh of solar onto a narrowboat, there simply isn't enough space. I have a 60' boat with most of the roof covered in solar and that's 2.1kWh.

 

The solar yield calculators predict about 7kWh/day average in summer, and that's what I see if moored unshaded -- this varies from 4kWh/day to 10kWh/day depending on the weather. In winter it would be far less than this, less than 2kWh/day. This is what I see when moored in the marina.

 

But this is not the case for a boat moving around where you're not always unshaded either while cruising or when moored. The best yield I saw for a week in June was 4kWh/day, only about 60% of predicted -- and the lowest for a week in October was 1.9kWh/day, 90% of the predicted 2.1kWh/day -- shading loss is less in winter since there's much less direct sun. Average over the year (with terrible weather!) was 3.2kWh/day, 70% of the predicted 4.6kWh.

 

My boat is all-electric including cooking, which is fine because though this takes significant power it's much smaller (about a third) than that needed for (electric) propulsion -- which is why I have a 35kWh 48V battery and 10kVA inverter/charger, so there's no added cost for electric cooking. Domestic power use per day over the year averaged out at 3.7kWh/day, depending on amount of cooking and washing (washer/drier on board) it ranged from 2kWh/day to 6kWh/day.

 

Note that solar power even in summer was not much bigger than domestic power use, though for sure the weather contributed to this -- but also the fact that solar yield when cruising (including at various moorings) was only about 60% of that predicted when moored in the marina in the full sun, because you're sometimes in the shade.

 

Electric cooking only really makes sense on a hybrid boat, where the electrics/battery/inverter needed to support it are already there for electric propulsion -- which in my case*** accounted for about three-quarters of total energy demand, domestic use was about a quarter. For a diesel boat, gas for cooking/kettle makes far more sense.

 

***this was cruising for an *average* of 5 hours per day while on board, which I suspect is a *lot* more than most boaters do... 😉 

And for the OP's benefit, note that Ian also has an onboard diesel generator which provides most of the power consumed by propulsion and domestic uses.

There's no way you can be a fossil fuel free liveaboard unless you have a mains connection (and that is still partly fossil fueled).

[Zen]

Wow wasn't expecting such a quick setfast reply

 

1 hour ago, Tony Brooks said:

 

Remember that the amount of solar you can get on the roof of a narrowboat is limited by the smaller roof area, so be very careful. I doubt solar will cover electric heating and cooking for much, if any, of the year. If you want that, plus eventual electric boating, I think that you will need a decent generator.

 

 

 

1 hour ago, IanD said:

 

There's no way you'll get 4.5kWh of solar onto a narrowboat, there simply isn't enough space. I have a 60' boat with most of the roof covered in solar and that's 2.1kWh.

 

 

I totally accept real estate is going to be the biggest issue here with pv panels and like I said I am in the research stage trying to match theory with reality. 

 

The youtuber May https://youtu.be/ 4vibWZ2ed4s (space inserted in address to stop it inlining) claims to have 4 x 1.5KW panels on her 62' boat. Personally the biggest I have seen in 700W but since I'm not full geek mode searching individual items yet, I'm still trying to understand all of the electrical components.

 

I've seen the new halfcell and bifacial solar panels are pushing the conversion rates higher.  I'm also looking at using a raspberry pi for auto sun tracking with the panels on the roof to maximise to load.

 

 

@Tony Brooks I didn't mean to imply that most people had electric boats,  I believe the complete opposite is true, I also agree that everybody's usage is different which is why I asked for what they are powering as well

 

@David Mack I did notice a lot of new boats had diesel heating, now I know why thanks.

 

@IanD That is a lot of battery capacity you have there, what is your battery setup? the solar collection values are rather disappointing, looks like I'll need to go serial hybrid when the motor is changed to electric. Thanks for all of the info, looks like I may be bugging you for info in time to come.

 

@nicknorman Thanks for the info, exactly what I'm after

 

[blackrose]

When I hear of people wanting to live on "all electric" boats I'm always puzzled as to why. If it's due to a genuine wish to live a "greener" lifestyle that is of course admirable, except that the reality is that living on a relatively poorly insulated boat which leaks waste water into the waterway isn't a particularly low environmental impact lifestyle in the first place. 

 

Improvements can always be made and electric propulsion and cooking may go some way in achieving those aims, however if a diesel generator has to be used for either then one can't help wondering how well the benefits really stack up. Also since any liveaboard boat will invariably be heated with fossil fuels in winter then the environmental benefits of "all electric" diminish further.

 

On the other hand if this type of "all electric" boat is done as a purely academic exercise and one is not delusional about the benefits then good luck to you.

[rogeriko]

So how many of these 535 watt panels could you fit along the roof.  

https://www.cityplumbing.co.uk/p/longi-solar-hi-mo-x6-535wp-black-frame-pv-module-lr5-66hth-535m/p/104460

 

These are the lithium batteries you want. 16 of these give you 17kwh of storage. 48v system to run an inverter or 24v if you double them up. 24v alternators are readily available, truck or bus.

 

https://www.fogstar.co.uk/collections/lifepo4

 

I use the 305ah ones and they power my entire house.

[cheesegas]

Here my setup if you’re after some more real world figures. I’m on a 45’ cruiser stern narrowboat, liveaboard year round with no shore power. Medium power usage I’d say - WiFi and fridge on year round, sometimes working from home with a laptop and 22” monitor. Over a 7 day period, I  average 1kwh/day consumption in winter and it’s up to 2kwh in summer. 

 

I’ve got 1kw of solar on the roof but could probably fit another 500w if I lost the coal storage area on the roof. 400ah of lifepo4, 90a alternator. Heating is via solid fuel stove and blown hot air diesel.  
 

Solar is enough to not have to run the engine/generator for power for roughly 8 months of year, sometimes a bit longer if I’m especially careful with mooring to make sure nothing shades the boat. Of those 8 months, for 3-4 months I use an air fryer and electric kettle toaster and run the washing machine from the batteries. 

Edited October 9 by cheesegas

[IanD]

18 hours ago, blackrose said:

 

Do you mean there's no way he'll get 4.5kW of solar panels onto a narrow boat and you have 2.1kW?

Of course -- too many posts recently about solar panel yield... 😞 

15 hours ago, blackrose said:

When I hear of people wanting to live on "all electric" boats I'm always puzzled as to why. If it's due to a genuine wish to live a "greener" lifestyle that is of course admirable, except that the reality is that living on a relatively poorly insulated boat which leaks waste water into the waterway isn't a particularly low environmental impact lifestyle in the first place. 

 

Improvements can always be made and electric propulsion and cooking may go some way in achieving those aims, however if a diesel generator has to be used for either then one can't help wondering how well the benefits really stack up. Also since any liveaboard boat will invariably be heated with fossil fuels in winter then the environmental benefits of "all electric" diminish further.

 

On the other hand if this type of "all electric" boat is done as a purely academic exercise and one is not delusional about the benefits then good luck to you.

 

If I say another hundred times that the reasons for "going electric" (for propulsion) are not savings or being "eco", will it sink in?

 

Likewise that it certainly doesn't make sense if cost is your concern, even more so for "gas-free" diesel boats -- which really make no sense at all unless you have gasexplosionphobia...

 

As many people have said many times, the reason for "going electric" is silent cruising, and it's an expensive luxury for those who value this -- which transforms the experience of boating, as everyone who has tried it has said. You do have to run a generator some of the time but for much shorter periods than a diesel engine, and these can often be arranged to be times when any (quiet) noise isn't bothering anyone. It does use less fuel than a diesel boat, but in the big CO2 picture the savings are negligible -- and the cost saving will never make up for the upfront cost.

 

There's currently no alternative to fossil fuel for heating, it would be great if HVO became widely available for those with diesel heaters or stoves but it isn't yet -- though some of us are trying to make that happen (the IWA working group). Heat pumps increase the electric power need even more, and don't make sense unless you're plugged in -- or can recharge that way, see below.

 

The only way "electric boating" will ever deliver significant eco benefits -- and mean the generator can be junked, and fossil fuel heating replaced by a heat pump -- is when there's a network of charging points on the canals, and there's currently no realistic prospect of that happening... 😞 

Edited October 9 by IanD

[Zen]

@rogeriko On my unbought boat I'd probably go with https://www.cityplumbing.co.uk/p/longi-solar-hi-mo-6-430wp-full-black-pv-module-lr5-54htb-430m/p/836339 instead that way I could lay the longest length across the width of the boat and then it is all down to the length of the roof less issues with vents and centre line. If a 60' has 45' / 14m of roof and if everything was perfect then 13 panels could fit giving about 5.5kw more likely 10 would but that would still give 4.3kw

 

I'm talking to a chap at fogstar about their batteries as I was looking at their rackmounts (originally I was looking at their 280AH drifts) but those are build your own battery packs? i.e. the cells for the battery?

 

@blackrose The reason is a bit of everything if I'm honest. Without going into life's sob story, I had a rather bad run for the last few years and although I still have a way to go before I retire, I want to reduce my outgoings and try and enjoy what time I have left (no I'm not dying as far as I'm aware but have reached the point in life where the want of security outweighs the want of luxury, at least sometimes) but I also need a project to keep my mind busy.  So trying to design a narrowboat from the ground up and having it as reliant on electricity is a good project with the added bonus of once I bought the boat I'll have to convert it. I fully understand the significant cost of converting it, but once done,  the ongoing costs of living in the boat should be lower (even factoring in monthly savings for replacement batteries and motor)

 

@cheesegas Thanks for the figures, again really helpful

[IanD]

16 minutes ago, Zen said:

@rogeriko On my unbought boat I'd probably go with https://www.cityplumbing.co.uk/p/longi-solar-hi-mo-6-430wp-full-black-pv-module-lr5-54htb-430m/p/836339 instead that way I could lay the longest length across the width of the boat and then it is all down to the length of the roof less issues with vents and centre line. If a 60' has 45' / 14m of roof and if everything was perfect then 13 panels could fit giving about 5.5kw more likely 10 would but that would still give 4.3kw

 

I'm talking to a chap at fogstar about their batteries as I was looking at their rackmounts (originally I was looking at their 280AH drifts) but those are build your own battery packs? i.e. the cells for the battery?

 

@blackrose The reason is a bit of everything if I'm honest. Without going into life's sob story, I had a rather bad run for the last few years and although I still have a way to go before I retire, I want to reduce my outgoings and try and enjoy what time I have left (no I'm not dying as far as I'm aware but have reached the point in life where the want of security outweighs the want of luxury, at least sometimes) but I also need a project to keep my mind busy.  So trying to design a narrowboat from the ground up and having it as reliant on electricity is a good project with the added bonus of once I bought the boat I'll have to convert it. I fully understand the significant cost of converting it, but once done,  the ongoing costs of living in the boat should be lower (even factoring in monthly savings for replacement batteries and motor)

 

@cheesegas Thanks for the figures, again really helpful

 

Going "gas-free" for cooking alone is not only expensive but it isn't even eco-friendly, unless your electric power comes from renewable sources. If it doesn't (e.g. a generator) then you'll burn more fuel to generate the power (a generator is about 25% efficient) than burning gas to cook on. It's also ultimately pointless eco-wise unless you also solve the problems of how to propel and heat the boat, which are *far* bigger energy consumers than cooking.

 

Unless you can rely solely on solar power and renewable energy -- neither of which is currently possible, as I explained above -- you're going to end up burning fossil fuels for heating and to generate at least some of the power for electric propulsion, assuming you actually want to go anywhere as opposed to sitting in a marina. And any savings in cost of living will be small and will never recoup your upfront costs.

 

That's not saying a hybrid boat without gas is a bad idea, if it was I wouldn't have one -- but the reasons for doing this are not the ones you're hoping for, especially any cost savings... 🙂 

 

Sorry if this isn't what you want to hear, but it's based on the realities of the canals today. In that future nirvana where there are charging points everywhere and we can throw away our generators and diesel heating things may well be rather different, but I'm not convinced this will happen in either of our lifetimes... 😉 

 

P.S. You're not going to get 1.72m long solar panels across the roof of a narrowboat either.

P.P.S. That blurb is lying about 25% efficiency, like all other similar panels they're about 22%.

Edited October 9 by IanD

[Gybe Ho]

1 hour ago, Zen said:

@rogeriko On my unbought boat I'd probably go with https://www.cityplumbing.co.uk/p/longi-solar-hi-mo-6-430wp-full-black-pv-module-lr5-54htb-430m/p/836339 instead that way I could lay the longest length across the width of the boat and then it is all down to the length of the roof less issues with vents and centre line. If a 60' has 45' / 14m of roof and if everything was perfect then 13 panels could fit giving about 5.5kw more likely 10 would but that would still give 4.3kw

 

 

How long are these panels? You will be limited to just under 5ft across the width of the cabin top.

 

BTW you need to subtract another 4ft from available roof space for the sliding entrance hatch at the rear.

 

If you can get more than 2.5kW on the roof of a used narrowboat then Newtonian and Einsteinian physics will will have to be rewritten.

[Zen]

@IanD I'd rather hear the truth than well meant lies of encouragement, this is partly why I am holding back from buying a boat right now as I want to know exactly what I am getting into, all the pros and the cons, and I am hearing you loud and clear, you are saying that if everyone went electric we could  save the world  

 

Seriously I do get it, at least in the UK, solar power is no where strong enough to completely power the boat and that it is cheaper and more environmentally friendly to use other fuel systems to heat and cook in the boat. 

 

The bonus of an electric motor is navigating the waters in near absolute silence but still requires a backup diesel generator and the fuel saved by this method will not repay the initial outlay unless being paid in silence is an acceptable currency.

 

With this in mind I have looked at the e-line 1100W and the EPod motors by Vetus (TBH hard to find another definite manufacturer) along with their 6/7KV generators, is this the system you are using and if not what do you use? I have had some difficulty verifying that they would work on a 62' narrow boat (I estimated the boat weight at 49000 lbs (62*6.18*2*64.2) LxWxDx lb per foot) and it kinda killed their online pdf calculator. Just want to see the viability of this option.

 

@Gybe Ho Remember it may well be over 1 year before I buy the boat but I will see what I can do on beating 2.5KW  

[Gybe Ho]

OP: It sounds as though low cost 365 days a year offgrid living aboard is your objective. This is a problem space my mind has been wallowing in for 6 months.

 

Let me accelerate your plans forward by 6 months because 6 months ago I was considering all the fringe stuff you are expending brain cycles on right now.

 

You need:

 

A narrowboat between 57ft and 62ft.

400 to 800Ah of lithium battery capacity.

1.2Kw to 1.8Kw of solar able to high tilt up to 80 degrees.

A 55 to 75 litre calorifier with solar dump.

Webasto 5kW diesel heater driving 3 to 4 radiators and heating plumbing routed through to a calorifier coil.

500 to 1000 litre water tank.

1 x 5kW solid fuel stove located in a central fore/aft position ideally.

1 x coal cage ( £ peanuts).

Gas cooking with alternatives to utilize free summer surplus solar.

Double glazing.

Above average insulation e.g. 25mm or more spray foam insulation and ideally 25mm insulation sheet under the floor and not a silly amount of window area.

Woolen socks, explorer thermal underwear, high tog duvet, 2 x water bottles and a large very expensive sheepskin rug.

 

Forget electric cooking and gas free boats. Liveaboards report using one 13kg gas bottle a quarter which just happens to equal 1kWh a day of cooking energy. Narrowboat liveaboard energy calcs are all about getting through the most dismal and cold 10 weeks of the year and that extra 1kWh of electric cooking energy is the difference between getting through the winter or tow-path offgrid misery. Go gas or add a £12k genset to your upgrade budget.

 

 

[Tony Brooks]

17 minutes ago, Zen said:

is this the system you are using and if not what do you use?

 

Both Ian and Peter, both of who had a great deal to do with specifying their system and in Peter's case installing it as well. They kept a conventional drive line and used am "off the shelf" electric motor. Both chose different makes of motors. I am sure both will be along to advise. Remember, Vetus paint their products yellow in the hope that the punters think they are gold-plated when they discover the price of spares.

[nicknorman]

10 minutes ago, Gybe Ho said:

OP: It sounds as though low cost 365 days a year offgrid living aboard is your objective. This is a problem space my mind has been wallowing in for 6 months.

 

Let me accelerate your plans forward by 6 months because 6 months ago I was considering all the fringe stuff you are expending brain cycles on right now.

 

You need:

 

A narrowboat between 57ft and 62ft.

400 to 800Ah of lithium battery capacity.

1.2Kw to 1.8Kw of solar able to high tilt up to 80 degrees.

A 55 to 75 litre calorifier with solar dump.

Webasto 5kW diesel heater driving 3 to 4 radiators and heating plumbing routed through to a calorifier coil.

500 to 1000 litre water tank.

1 x 5kW solid fuel stove located in a central fore/aft position ideally.

1 x coal cage ( £ peanuts).

Gas cooking with alternatives to utilize free summer surplus solar.

Double glazing.

Above average insulation e.g. 25mm or more spray foam insulation and ideally 25mm insulation sheet under the floor and not a silly amount of window area.

Woolen socks, explorer thermal underwear, high tog duvet, 2 x water bottles and a large very expensive sheepskin rug.

 

Forget electric cooking and gas free boats. Liveaboards report using one 13kg gas bottle a quarter which just happens to equal 1kWh a day of cooking energy. Narrowboat liveaboard energy calcs are all about getting through the most dismal and cold 10 weeks of the year and that extra 1kWh of electric cooking energy is the difference between getting through the winter or tow-path offgrid misery. Go gas or add a £12k genset to your upgrade budget.

 

I would add to the bedding list an “all night” type electric blanket. The bedroom in our boat is at the back and a long way from the stove and we didn’t really want multiple duvets for different seasons. So we have a fairly light duvet and an “all night” thermostatically controlled electric under blanket that keeps us cosy all night and the Li batteries shrug off the power consumption.

[Gybe Ho]

19 hours ago, nicknorman said:

... So we have a fairly light duvet and an “all night” thermostatically controlled electric under blanket that keeps us cosy all night and the Li batteries shrug off the power consumption.

 

 

Have you calculated the cost in kWh? I did some reading up on these after seeing your post and guess the running cost is 8 hours at 50w to 100w, so call it 0.4 to 0.8 kWh daily for 6 months of the year. Am I far off?

[Zen]

@Gybe Ho Yes and no, I do want to get the cost down as much as possible but not at the cost of too much comfort, don't get me wrong I wasn't planning on dancing around the boat naked, apart from Friday nights of course, and don't have a problem wearing a few layers and/or jumper in the winter months but I don't want it any worse than that.

 

If during the summer months all I'm really paying for is:

CRT licence

insurance

Diesel for generator

gas for cooker

Wifi

 

Then all combined, even with the increase of licence costs coming in, this should be less than £350pm.  If I then double that to £700pm to account for monthly saving for Blacking and other large periodic costs. When it comes to the winter months it wont bother me if I need to spend an additional £100+pm to keep the boat warm so I don't freeze then that's fine. If I don't have to financially, I'm not prepared to be in my bed with a bobble hat on and outside clothing just so I'm not shivering in bed, I'm aware some people don't have that choice and my heart goes out to them, I've been in that position before and have no desire to return to it.

 

This being said even after I have bought the boat it may well be a year or more before it becomes a full time liveaboard, it will be more weekend working on it and holiday boating, convincing the misses to make the jump and leave the house is going to be the hard part.... although I may not argue to hard.

 

Thanks for your list, mine is very close to yours already.

 

55ft I think is my ideal length as with that there is only a few canals I cant travel through but another part of me wants the biggest I can get for panel space but then I still have to heat the volume below it so it becomes counter productive.

 

I want a higher battery capacity but that mainly because I'm still a gadget guy and have a few high powered items coming aboard if space allows.

 

With the Webasto 5kW diesel heater will that be enough? would the 9.1KW version be overkill?

 

I want 100Lt water tank but was unsure of both material (metal or plastic) and where it should go. I know a lot of ppl have in under their bow but is there an issue with it freezing there? do the water tanks have a gas and/or water overpressure valve?

 

I have been very surprised by the cost of double glazing + thermal break about £450 per window 

 

Insulation is something I'm still torn over, if the boat already has sprayfoam installation is it best to leave it or rip out and do again or is the foam board stuff just as good?