Proposed new accessible electric narrowboat.

[JungleJames]

On 18/12/2023 at 15:41, Andrew Grainger said:

Budget has yet to be established and is subject to the feasibility, that said I am realistic, this is not going to be cheap and it is possible it turns out to be simply uneconomic! 
Batteries will be costly but are getting cheaper all the time. 
As for grid power, some suppliers are much better than others eg Octopus. Also I have bought a  crowdfunded share of a large onshore wind farm and am installing solar and batteries at our home which together is sufficient to cover all my electricity needs, home and boat, with some surplus solar to export. 

Sorry, saying any supplier of electricity is better than another is a myth. It all comes from the grid.

 

So to make things simple, lets say there are 2 suppliers- Octopus and X, with Octopus being new.

Octopus claims 100% renewable electricity, but X makes no claims at all.

 

Lets say you have 2 sources of power into the national grid- Coal and wind, just to make things simple. Both are at 50%. Lets say 100mw each.

 

Previously, X supplied 200mw of electricity, split evenly, 50/ 50.

Octopus turns up, and gains contracts for 100mw of supposedly green electricity. With X losing the same.

Octopus says to the grid they want 100mw of green electricity.

No problem. How do you manage that? Simple. Wind is already providing 100mw of electricity, so just tell Octopus that all their electricity comes from wind (in reality, clearly nobody knows where your electrons came from).

X then gets supplied with 100mw of non green electricity because they have not requested one or the other (but again, who knows where the individual electrons come from?)

 

The reality? The split is still 50/50. But Octopus claim to be supplying green electricity. X, who never claimed anything, were however already supplying this 100mw of green electricity as it was.

 

The only way Octopus could be as good as claimed, is if say they gained 150mw of green contracts, outdoing the amount of electricity provided by green sources. They would then have to put up their own wind farms to cover this extra 50mw, and charge the National Grid such a small amount, that the National Grid told one of the coal stations to throttle back by 50mw as they were now too expensive.

 

 

 

 

 

[magnetman]

Tiny power stations. 

 

 

[BoatinglifeupNorth]

11 minutes ago, IanD said:

A somewhat longer boat in the 57'-60' range won't cost much more since it still needs all the same equipment (just a bit more steel and fitout), will still be "go-anywhere", will have considerably more space inside (up to 50% extra), and will be much easier to resell if that ever becomes necessary. All the same applies even more to a full length boat (70'-72') except the "go-anywhere" (and maybe easier to resell?) bit... 😉

Sounds like the OP has EOG moorings maybe thats the 45ft thing, I think the majority of owners having new builds wouldn’t spend that sort of money on a boat so small, more like a 57’-60’. As you say.

 As @Andrew Grainger has a Narrowboat already maybe it would be a lot cheaper to alter this to suit his new needs?

[Up-Side-Down]

On 19/12/2023 at 13:42, IanD said:

 

Finesse did my complete boat installation, they supplied the motor which I believe is a custom version of the Engiro 12013 to further optimise torque/rpm. The prop is a custom 4-blade from Michigan Marine, I wanted this for lower noise and vibration compared to a 3-blade and this seems to have worked -- but they didn't have any 4-blade blanks with the right diameter/pitch/boss/prop shaft size so it had to be specially machined down (including the boss) from a bigger one, yet more cost... 😞

 

https://mmp-i.com/leisure/canal/canal-line-propellers/

 

The motor and drive are pretty much inaudible at normal speeds, all you get is the gurgle from the prop wash. Flat out the wash is considerably noisier but the boat is still very quiet compared to a diesel, even with the generator running.

Yep, it's 'gurgle' I'm after, not a 'whine' and a 'whir'!

 

Are the Engiro motor and controller water- or air-cooled btw?

[IanD]

1 hour ago, Up-Side-Down said:

Yep, it's 'gurgle' I'm after, not a 'whine' and a 'whir'!

 

Are the Engiro motor and controller water- or air-cooled btw?

 

Both water-cooled -- the motor uses a small pump (which IIRC only comes on above 10kW), the controller is bolted down to the hull (on the uxter plate IIRC).

 

The motor is also flexibly mounted and enclosed (by Finesse) in panels lined with sound insulation, like the cocooned (Kohler) generator.

 

Which is also mounted on a 200kg inertia frame on flexible feet to further reduce vibration and noise, and uses two silencers to reduce exhaust noise, and has extra soundproofing under the hatches and on the bulkhead.

 

Yes I was paranoid about getting everything as quiet and vibration-free as possible -- which is the whole point, surely? 😉

Edited December 20, 2023 by IanD

[Matt Wardman]

On 16/12/2023 at 22:53, Andrew Grainger said:

Thanks for all the comments, I am new to this forum.
To clarify, the proposal is a new build Narrowboat, c45ft length. With a permanent mooring with shore power when required. Part time live aboard, part time cruising, some extended cruises though minimal in winter months.
Objective is to fit out to standards as close as possible equivalent to pasivhaus for housing. 
So, all electric (engine, heating, cooking), high levels of insulation, MVHR with air filtration and dehumidifier, max solar PV. Accessibility for as we age. 
Examples, contacts, ideas all welcome thank you. 

 

(This is a longish post, but I want to make a case. Apologies if I am teaching granny to suck eggs - this is also for myself.)

 

I think the low-energy narrowboat <> passive house comparison is interesting, but I'd think that a comparison to a 'typical' narrowboat might be as fruitful - as houses and narrowboats work quite differently.

AIUI (as a serial renovator / self-builder and a MOD on the main UK self-build forum) a passive house achieves cost-effectiveness through radical reduction in energy requirement then retaining the heat, mainly heating through a pairing of reduced heat loss via superinsulation / physcial shape (ie being squarish) and reducing air leakage. Superinsulation means 5-8" of PIR (Celotex / Kingspan) in every external surface including roof and floor.

 

Heating demand may be reduced by 80-90%, which allows a switch to all-electric, and the costs still to be well below a traditional gas-fired house. It is possible for a normal size passivehaus to have no heating upstairs except a towel radiator, maybe UFH downstairs, and a single plug in fan heater for when it is below zero in winter. They also are often set up as one or two zones only because the shell of the house is the heat/air boundary, which saves ££££ on posh heating controllers. Left completely alone and all switched off the internal temperature may fall by 1C over a weekend. It is sometimes the case that routine heating can be done via a small (say 500W) heating element in the MVHR (mechanical ventilation with Heat Recovery) air intake, but that is sometimes marginal in practice.

 

For a passive house, overheating is as much a problem as cold, so reversible Air to Air heat pumps, which can be run backwards in high summer and are far more efficient than traditional AC, are becoming much more popular. I currently use a largish (~3kW heating / cooling capacity from ~1.3kW input power) portable heatpump AC/Dehumidifer in my own (well-insulated but not passive) house to make the central heating season a few weeks shorter in the shoulder months, which seems to work OK.

Comparing to a narrowboat, there is not physically room for that much insulation (except maybe floor / ceiling?), and the lifestyle is open-doors usually - which makes heat retention difficult through the gangway being through all the indoor spaces, and the physical form factor is far less favourable to heat retention. I make the surface area:volume ratio of a narrowboat around 2.25, whilst that for an 8mx8mx8m house is around 0.75.

One effect worth a note is that passive houses suffer less from draughts when one door is opened - because there is nowhere for the air to escape the house, it tends not to blow in. Helpful to narrowboat life?

 

As an aside, people in passive houses who want a log burner often end up using 3-4kw boat-heaters, because anything 'normal' turns the place into a furnace very quickly. 

So where does that leave LENBs (Low Energy NarrowBoats)?

 

I'd suggest that it is a game of marginal gains in everything, with a goal of reducing the total energy usage of the electric boat, which can be banked either as needing fewer batteries which take up less space , or a smaller genny, or as an increase in "self-sufficient without charge / connected to shore" duration.

 

For goals, perhaps a 50-75% reduction in 'domestic' energy requirement and 10-20% in propulsion energy requirement over a 'typical' narrowboat are ambitious but forseeable - which will then reduce use of generators etc? There's a lot of energy modelling to be done, but there are tools around to do it.

 

I think that if airtightness is pursued a total removal of gas / wood / diesel appliances in the residential space may be wise, unless room-sealed. I can see the CRT having kittens if not.

 

For fruitful areas, I'd note recent developments in self-contained ventilation, and heating / cooling appliances using heat pumps designed for small apartments. eg There are now "through the wall" installable heat / cool air to air heat pumps on the market.

 

I have ideas about specifics, but this post is long enough. I'll post again if there is interest.

ATB all.

Edited December 21, 2023 by Matt Wardman

[Up-Side-Down]

I certainly think so!

[BoatinglifeupNorth]

@Matt Wardman welcome to the forum, hopefully your knowledge of heating/insulation will be helpful and it was good to see that you understand that requirements for Narrowboats and houses are different and not saying everything will work on a boat.👍

[David Mack]

3 hours ago, Matt Wardman said:

Comparing to a narrowboat, there is not physically room for that much insulation (except maybe floor / ceiling?)

Probably some scope for underfloor insulation, although most boats don't have any. But additional ceiling insulation would result in an unacceptable loss of internal headroom in most boats.

 

How does the U value of 1-2" of sprayfoam onto 3-6mm of steel compare with typical house building materials?

[IanD]

4 hours ago, Matt Wardman said:

 

(This is a longish post, but I want to make a case. Apologies if I am teaching granny to suck eggs - this is also for myself.)

 

I think the low-energy narrowboat <> passive house comparison is interesting, but I'd think that a comparison to a 'typical' narrowboat might be as fruitful - as houses and narrowboats work quite differently.

AIUI (as a serial renovator / self-builder and a MOD on the main UK self-build forum) a passive house achieves cost-effectiveness through radical reduction in energy requirement then retaining the heat, mainly heating through a pairing of reduced heat loss via superinsulation / physcial shape (ie being squarish) and reducing air leakage. Superinsulation means 5-8" of PIR (Celotex / Kingspan) in every external surface including roof and floor.

 

Heating demand may be reduced by 80-90%, which allows a switch to all-electric, and the costs still to be well below a traditional gas-fired house. It is possible for a normal size passivehaus to have no heating upstairs except a towel radiator, maybe UFH downstairs, and a single plug in fan heater for when it is below zero in winter. They also are often set up as one or two zones only because the shell of the house is the heat/air boundary, which saves ££££ on posh heating controllers. Left completely alone and all switched off the internal temperature may fall by 1C over a weekend. It is sometimes the case that routine heating can be done via a small (say 500W) heating element in the MVHR (mechanical ventilation with Heat Recovery) air intake, but that is sometimes marginal in practice.

 

For a passive house, overheating is as much a problem as cold, so reversible Air to Air heat pumps, which can be run backwards in high summer and are far more efficient than traditional AC, are becoming much more popular. I currently use a largish (~3kW heating / cooling capacity from ~1.3kW input power) portable heatpump AC/Dehumidifer in my own (well-insulated but not passive) house to make the central heating season a few weeks shorter in the shoulder months, which seems to work OK.

Comparing to a narrowboat, there is not physically room for that much insulation (except maybe floor / ceiling?), and the lifestyle is open-doors usually - which makes heat retention difficult through the gangway being through all the indoor spaces, and the physical form factor is far less favourable to heat retention. I make the surface area:volume ratio of a narrowboat around 2.25, whilst that for an 8mx8mx8m house is around 0.75.

One effect worth a note is that passive houses suffer less from draughts when one door is opened - because there is nowhere for the air to escape the house, it tends not to blow in. Helpful to narrowboat life?

 

As an aside, people in passive houses who want a log burner often end up using 3-4kw boat-heaters, because anything 'normal' turns the place into a furnace very quickly. 

So where does that leave LENBs (Low Energy NarrowBoats)?

 

I'd suggest that it is a game of marginal gains in everything, with a goal of reducing the total energy usage of the electric boat, which can be banked either as needing fewer batteries which take up less space , or a smaller genny, or as an increase in "self-sufficient without charge / connected to shore" duration.

 

For goals, perhaps a 50-75% reduction in 'domestic' energy requirement and 10-20% in propulsion energy requirement over a 'typical' narrowboat are ambitious but forseeable - which will then reduce use of generators etc? There's a lot of energy modelling to be done, but there are tools around to do it.

 

I think that if airtightness is pursued a total removal of gas / wood / diesel appliances in the residential space may be wise, unless room-sealed. I can see the CRT having kittens if not.

 

For fruitful areas, I'd note recent developments in self-contained ventilation, and heating / cooling appliances using heat pumps designed for small apartments. eg There are now "through the wall" installable heat / cool air to air heat pumps on the market.

 

I have ideas about specifics, but this post is long enough. I'll post again if there is interest.

ATB all.

 

There's just a limit to what can be done to improve insulation and reduce heat losses on a narrowboat given space and construction constraints. My boat has sprayfoam insulation a couple of inches thick, double-glazed portholes/side doors instead of big windows, and pretty much the minimum free-air ventilation (i.e. not much!) allowed by BSS for a gas-free boat e.g. no mushrooms or flying saucers on the roof, no louvre vents in doors/bulkheads. Heating is a diesel boiler (which I'd like to run on HVO, if I could get it...) because a water-source heatpump won't work in winter and an air-source one is too big and noisy. Excess solar power in summer (if I ever have any!) can be diverted into providing hot water via the calorifier.

 

All this must reduce heating energy use somewhat, but it's difficult to see what more could be done without a suitable water-source heat pump -- which doesn't exist today and may not be possible, see earlier posts.

 

Energy for propulsion can be reduced by much more compared to a traditional diesel boat, even if all the power comes from a generator the saving is typically getting on for 50% due to higher efficiency especially when going slowly past moored boats or in locks -- while cruising continuously at full speed the saving is less than this, if you pootle along slowly the saving can be more. In summer where some energy for propulsion can come from solar the savings are bigger, a lightly used boat may well be able to use only solar power.

 

Like EVs the thing that would make a *big* difference would be if the boat could be run from grid power (currently rising towards 50% renewables) but this would need canalside charging stations, which realistically there is no plan for.

 

And even if you did all this to get personal satisfaction from being green, there are 1000x more cars and houses in the UK than boats on CART waterways so the contribution to UK emissions would be tiny -- about the same as reducing the number of cars on the roads by 0.1%, or driving each of them 10 miles less every year... 😞

Edited December 21, 2023 by IanD

[magnetman]

I like a Boat with big windows moored in a nice place with a good view and a big wood fire. 

 

I have one of these at the country estate but for the inner city a bunker is better with a coal fire which will happily take road cones and old tyres reduced to a suitable size and briquetted dead birds and rodents. 

 

I've been eyeing up the duckweed and wondering how this could be converted to a fuel product for use in the favela. 

 

 

[Up-Side-Down]

1 hour ago, IanD said:

 

There's just a limit to what can be done to improve insulation and reduce heat losses on a narrowboat given space and construction constraints. My boat has sprayfoam insulation a couple of inches thick, double-glazed portholes/side doors instead of big windows, and pretty much the minimum free-air ventilation (i.e. not much!) allowed by BSS for a gas-free boat e.g. no mushrooms or flying saucers on the roof, no louvre vents in doors/bulkheads. Heating is a diesel boiler (which I'd like to run on HVO, if I could get it...) because a water-source heatpump won't work in winter and an air-source one is too big and noisy. Excess solar power in summer (if I ever have any!) can be diverted into providing hot water via the calorifier.

 

All this must reduce heating energy use somewhat, but it's difficult to see what more could be done without a suitable water-source heat pump -- which doesn't exist today and may not be possible, see earlier posts.

 

Energy for propulsion can be reduced by much more compared to a traditional diesel boat, even if all the power comes from a generator the saving is typically getting on for 50% due to higher efficiency especially when going slowly past moored boats or in locks -- while cruising continuously at full speed the saving is less than this, if you pootle along slowly the saving can be more. In summer where some energy for propulsion can come from solar the savings are bigger, a lightly used boat may well be able to use only solar power.

 

Like EVs the thing that would make a *big* difference would be if the boat could be run from grid power (rising towards 50% renewables) but this would need canalside charging stations, which realistically there is no plan for.

 

And even if you did all this to get personal satisfaction from being green, there are 1000x more cars and houses in the UK than boats on CART waterways so the contribution to UK emissions would be tiny -- about the same as reducing the number of cars on the roads by 0.1%, or driving each of them 10 miles less every year... 😞

 

1 hour ago, Up-Side-Down said:

(which I'd like to run on HVO, if I could get it...)

If you can handle either 205 litre drums or 1000 litre IBCs then contact Ryan Abreu, Crown Oil, on 07585 792918; r.abreu[at]crownoil.co.uk. Crown will deliver by tanker in the Lancs/Yorks/Manchester area, while their subsiduariaries – Beesleys in the Midlands and Speedy Fuels in the Home Counties – will also deliver by tanker. I have been collecting IBCs from their Bury HQ for a couple of years now, alongside IBC pallet deliveries sent up here to Scotland. It's worth noting that two 205 litre drums sit on a pallet, so best bought as a pair to minimise transport costs.

 

Now that the HVO Fuels Group (made up of IWA, RYA and CA members) have successfully lobbied DfT to allow HVO to be used for both propulsion and 'domestic' purposes under the RTFO (thereby attracting RTFC 'subsidy' across the board) 'red' HVO has suddenly become straightforward to purchase for ALL inland waterways use.

 

The Group has now turned its attention to making the fuel readily available and affordable as, currently, it is 50% more expensive than gas oil. They are also lobbying DfT to extend HVO use under the RTFO mechanism to lumpy water boats so that all recreational craft are covered (and therefore treated alike).

RTFO communique no. 14 – 2023.pdf

Edited December 21, 2023 by 1st ade
Email address - "obfuscated"

[Andrew Grainger]

5 hours ago, Matt Wardman said:

 

(This is a longish post, but I want to make a case. Apologies if I am teaching granny to suck eggs - this is also for myself.)

 

I think the low-energy narrowboat <> passive house comparison is interesting, but I'd think that a comparison to a 'typical' narrowboat might be as fruitful - as houses and narrowboats work quite differently.

AIUI (as a serial renovator / self-builder and a MOD on the main UK self-build forum) a passive house achieves cost-effectiveness through radical reduction in energy requirement then retaining the heat, mainly heating through a pairing of reduced heat loss via superinsulation / physcial shape (ie being squarish) and reducing air leakage. Superinsulation means 5-8" of PIR (Celotex / Kingspan) in every external surface including roof and floor.

 

Heating demand may be reduced by 80-90%, which allows a switch to all-electric, and the costs still to be well below a traditional gas-fired house. It is possible for a normal size passivehaus to have no heating upstairs except a towel radiator, maybe UFH downstairs, and a single plug in fan heater for when it is below zero in winter. They also are often set up as one or two zones only because the shell of the house is the heat/air boundary, which saves ££££ on posh heating controllers. Left completely alone and all switched off the internal temperature may fall by 1C over a weekend. It is sometimes the case that routine heating can be done via a small (say 500W) heating element in the MVHR (mechanical ventilation with Heat Recovery) air intake, but that is sometimes marginal in practice.

 

For a passive house, overheating is as much a problem as cold, so reversible Air to Air heat pumps, which can be run backwards in high summer and are far more efficient than traditional AC, are becoming much more popular. I currently use a largish (~3kW heating / cooling capacity from ~1.3kW input power) portable heatpump AC/Dehumidifer in my own (well-insulated but not passive) house to make the central heating season a few weeks shorter in the shoulder months, which seems to work OK.

Comparing to a narrowboat, there is not physically room for that much insulation (except maybe floor / ceiling?), and the lifestyle is open-doors usually - which makes heat retention difficult through the gangway being through all the indoor spaces, and the physical form factor is far less favourable to heat retention. I make the surface area:volume ratio of a narrowboat around 2.25, whilst that for an 8mx8mx8m house is around 0.75.

One effect worth a note is that passive houses suffer less from draughts when one door is opened - because there is nowhere for the air to escape the house, it tends not to blow in. Helpful to narrowboat life?

 

As an aside, people in passive houses who want a log burner often end up using 3-4kw boat-heaters, because anything 'normal' turns the place into a furnace very quickly. 

So where does that leave LENBs (Low Energy NarrowBoats)?

 

I'd suggest that it is a game of marginal gains in everything, with a goal of reducing the total energy usage of the electric boat, which can be banked either as needing fewer batteries which take up less space , or a smaller genny, or as an increase in "self-sufficient without charge / connected to shore" duration.

 

For goals, perhaps a 50-75% reduction in 'domestic' energy requirement and 10-20% in propulsion energy requirement over a 'typical' narrowboat are ambitious but forseeable - which will then reduce use of generators etc? There's a lot of energy modelling to be done, but there are tools around to do it.

 

I think that if airtightness is pursued a total removal of gas / wood / diesel appliances in the residential space may be wise, unless room-sealed. I can see the CRT having kittens if not.

 

For fruitful areas, I'd note recent developments in self-contained ventilation, and heating / cooling appliances using heat pumps designed for small apartments. eg There are now "through the wall" installable heat / cool air to air heat pumps on the market.

 

I have ideas about specifics, but this post is long enough. I'll post again if there is interest.

ATB all.

Thank you that is really interesting and helpful. We are certainly intending to exclude any burning of any kind, diesel, LPG, solid fuel. Absolutely no stove. I agree one of the biggest challenges is maximising insulation without overly compromising space and I shall be exploring g new materials. 
certainly interested in your thoughts on heat pumps appropriate for these situations. 

[IanD]

39 minutes ago, Andrew Grainger said:

Thank you that is really interesting and helpful. We are certainly intending to exclude any burning of any kind, diesel, LPG, solid fuel. Absolutely no stove. I agree one of the biggest challenges is maximising insulation without overly compromising space and I shall be exploring g new materials. 
certainly interested in your thoughts on heat pumps appropriate for these situations. 

Unless you're going to spend most of your time in a marina with a shoreline connection (grid power) and only leave for short trips (battery power), or travel only slowly and for relatively short periods in the summer (solar power), you're simply not going to be able to avoid burning *something* on an electric/hybrid narrowboat to provide power/energy for heating or onboard power or propulsion, and no amount of better insulation (which you can't fit in on a narrowboat anyway) is going to change this... 😞

 

You need to do a proper power/energy audit for all energy consumers and generators on the boat along with realistic yields for solar power. The numbers are unlikely to add up without burning something -- HVO is the best option, if you can get it... 😉

Edited December 21, 2023 by IanD

[Up-Side-Down]

6 minutes ago, IanD said:

Unless you're going to spend most of your time in a marina with a shoreline connection (grid power) and only leave for short trips (battery power), or travel only slowly and for relatively short periods in the summer (solar power), you're simply not going to be able to avoid burning *something* on an electric/hybrid narrowboat to provide power/energy for heating or onboard power or propulsion, and no amount of better insulation (which you can't fit in on a narrowboat anyway) is going to change this... 😞

 

You need to do a proper power/energy audit for all energy consumers and generators on the boat along with realistic yields for solar power. The numbers are unlikely to add up without burning something -- HVO is the best option, if you can get it... 😉

You can,  no problem – see my post above!

[IanD]

8 minutes ago, Up-Side-Down said:

You can,  no problem – see my post above!

Not being able to store 1000l IBCs or even 200l drums of HVO (like many boaters?), "available" to me means "at marinas and boatyards where boats can fill up their tanks from a pump" -- which hopefully will happen now the tax/subsidy situation has changed, but hasn't yet... 😉

 

HVO is a much better option than diesel for all sorts of reasons, but still doesn't meet the stated "not burning anything" target -- which I think is simply unrealistic except in a few special cases... 😞

Edited December 21, 2023 by IanD

[Matt Wardman]

32 minutes ago, IanD said:

Not being able to store 1000l IBCs or even 200l drums of HVO (like many boaters?), "available" to me means "at marinas and boatyards where boats can fill up their tanks from a pump" -- which hopefully will happen now the tax/subsidy situation has changed, but hasn't yet... 😉

 

HVO is a much better option than diesel, but still doesn't meet the stated "not burning anything" target -- which I think is simply unrealistic except in a few special cases... 😞

I'm inclined to agree with that second para.

 

If I can make a comparison I'd say that LENBs are at a stage where low energy houses were 20 or 25 years ago - a lot could be, and was,achieved, but it was to an extent about pioneering, could be complicated and expensive, a little esoteric and might involve lifestyle compromises. 

Does anyone remember Justin Rowlatt being the "Newsnight Ethical Man" for a year in 2006 trying to reduce his environmental impact, doing all sorts of things with his house and lifestyle? They achieved a 20% reduction in Carbon Footprint.

 

As an example, Ground Source Heat Pumps were perceived as important back then, but are now recognised as a specialist thing requiring a major up front investment (digging 100s of m of trench, the cost of that and all the pipe, and especially all the antifreeze to fill it up with). So now we usually prefer ASHPs driving radiators or UFH (under floor heating), or Air-to-Air heat pumps which can be run backwards in summer.

 

As a data point, the first UK *registered* (which most don't do as it adds a few thousand to the cost) passivehaus was around 2008.

Now we are about to have "net zero" coming in as part of basic Building Regulations, and building a carbon-positive house is not difficult. Renovating an existing house to be nearly net zero is more difficult, but doable.

So I agree that a LENB is likely to need options and backups (eg a genny to recharge batteries if an electric drivetrain is installed), but that is a big step forward on the LENB journey. And over time limitations should reduce until suddenly in a decade or two major further energy reduction will be doable will just a few compromises. I love the idea that short term achievements are usually less than desired, but long-term achievements are often more than expected.

 

@magnetman, duckweed contains lots of protein (allegedly), and in 2019 a study was published entitled "Duckweed as human food. The influence of meal context and information on duckweed acceptability of Dutch consumers."

I'd suggest Googling it if your intentions are serious 😋, as I am not sure whether I can post links yet. It is popular in Thailand and Laos. (I said I follow rabbit holes.)

 

Perhaps duckweed lava bread & free range mallard is the new bacon sarnie?

Edited December 21, 2023 by Matt Wardman

[IanD]

34 minutes ago, Matt Wardman said:

I'm inclined to agree with that second para.

 

If I can make a comparison I'd say that LENBs are at a stage where low energy houses were 20 or 25 years ago - a lot could be - and was - achieved, but it was top an extent about pioneering , complicated, a little esoteric and might involve lifestyle compromises.

 

As an example, Ground Source Heat Pumps were perceived as important back then, but are now recognised as a specialist thing requiring a major up front investment (digging 100s of m of trench, the cost of that and all the pipe, and especially all the antifreeze to fill it up with). The first UK *registered* (which most don't do as it adds a few thousand to the cost) passivehaus was around 2008. So now we usually prefer ASHPs driving radiators or UFH (under floor heating), or Air-to-Air heat pumps which can be run backwards in summer.

Now we are about to have "net zero" coming in as part of basic Building Regulations, and building a carbon-positive house is not difficult. Renovating an existing house to be nearly net zero is more difficult, but doable.

So I agree that a LENB is likely to need options (eg a genny to recharge batteries if an electric drivetrain is installed), but that is a big step forward on the LENB journey. And over time limitations should reduce until suddenly in a decade or two it will be doable will just a few compromises. I love the idea that short term achievements are usually less than desired, but long-term achievements are often more than expected.

 

@magnetman, duckweed contains lots of protein (allegedly), and in 2019 a study was published entitled "Duckweed as human food. The influence of meal context and information on duckweed acceptability of Dutch consumers."

I'd suggest Googling it if your intentions are serious 😋, as I am not sure whether I can post links yet. It is popular in Thailand and Laos.

 

Perhaps one can make duckweed lava bread?

 

(I said I follow rabbit holes.)

 

It's difficult to see what is going to be different in a few years from now (or even 10...) for narrowboats; there still won't be a canal-wide network of charging points to allow true electric boating, solar panels still won't deliver enough power for propulsion except for limited use in summer (and not at all in winter), heating will still be the biggest problem even if you don't move much (especially in winter). Even if a usable water source heat pump comes along (or a suitable air source one) then it'll still consume a lot of power which has to come from somewhere, especially in winter. A "magic" insulation material usable in boats (and affordable) is unlikely to come along, they all basically rely on trapped air in a low-conductivity matrix of some kind, and sprayfoam is pretty good at this.

 

Without solving these fundamental problems -- and there's no obvious "magic technology" wand that can be waved to make this happen -- electric/hybrid narrowboats are still going to have to burn some kind of fuel for power/heating/propulsion, for which HVO or something similar is the best option, and they're still going to need an onboard generator for year-round gas-free living/moving. A wideboat has more chance of coping with solar for a much bigger part of the year, but will still have difficulties in winter with little sun and increased heating demand.

 

Low-energy houses don't have these basic problems, because they can have far thicker insulation (e.g. 200mm), lots more solar (big roofs!), can use heat pumps, and have access to a grid with an increasing percentage of renewable power. These are fundamental differences to narrowboats -- or even wideboats to a lesser degree.

 

The *only* long-term fix for all this is mains charging points (and big batteries), for the same reason it is for EVs -- and then boats could get rid of the generator and burning stuff like hybrid cars do. Unfortunately there's no strategy or plan to make this happen... 😞

Edited December 21, 2023 by IanD

[magnetman]

Go juice is the answer. 

 

It looks like Ribena but has a very satisfactory flame spread and expansion when atomised and compressed. 

 

One could arrange for the combustion to be internal for safety reasons. 

 

 

[Ronaldo47]

A columnist in "Modern Railways" , when discussing government's reluctance to invest in conventional electrification because some new, innovative, cheaper method of propulsion might be invented in the future, has been referring to this as the "bionic duckweed" solution.

[Matt Wardman]

I've been playing with numbers for an hour around heat loss (and therefore demand). Here are few links if anyone is interested.

My "model LENB" is a 57 footer with a 2m x 2m x 12m enclosed living space, with 4.5 sqm of windows, and 3.2 sqm of doors.

 

Playing with differing conditions suggests that static heat loss to air and heat conduction is anything between about 400W and 2000W, depending on spec and conditions, and a best "worst case" loss (90mm of spray foam insulation, internal temp 20C, external temp 0C, water temp 3C) is around 800W. This assumes no air leakage in a steady state except via the MVHR or similar.

That suggests that a small heater - even an inline one in an MVHR style system - is possible even for most of winter, bearing in mind that 2 people and a dog output about 250 watts, and there is heat from cooking etc. But such a setup will hit the batteries if kept running continuously, which has consequences in more batteries needed and/or genny use.

 

Normal narrowboat data (from Collingwood, their - expensive - "Shearwater" model. £100-150k sailaway & fitted out).
https://newandusedboat.co.uk/wp-content/uploads/2020/05/Shearwater_Spec_Apr20.pdf

 

Electric narrowboat data, (from Mothership, even more expensive. £200-250k sailaway & fitted out).

https://mothershipmarine.com/faq/

BSS suggest 2 air changes per hour (ACH) to deliver safety wrt carbon monoxide; so I'm using 1-2 changes per hour as my datum for the ss. If you want to ignore MVHR and model open vents, set its efficiency to zero.

 

VESMA online calculator for working out the U-value of a layered wall. PIR is Poly "IsanocyanuRate" (in the list). In practice ignore the steel and the inside cladding as de minimus.

https://vesma.com/tutorial/uvalue01/uvalue01.htm

Buildhub Fabric & ventilation heat loss calculator. Simple, but complex enough to be useful:

https://forum.buildhub.org.uk/topic/439-fabric-and-ventilation-heat-loss-calculator/

 

I like it that boatbuilders don't tell me how much insulation it has - just "highly insulated". I wonder why - perhaps because it isn't 🙃.

If there is interest, we could do a LENB thread to explore the question and other aspects further.

 

Edited December 21, 2023 by Matt Wardman

[magnetman]

I like having a wood stove on the Boat and the doors open.

 

Not being able to do this due to inadequate heating would make living in such a confined space quite arduous I think.

 

Of course this is not about liveaboard Boats so can be discounted.

 

 

[Matt Wardman]

I'd definitely concur that 12-month liveaboard is the extreme case, and "Part time live aboard" with some cruising in winter - as suggested by the OP - is more of a middle case.

 

I think it is interesting exploring what is possible / practical today. It's another set of possible compromises.

 

People with asthma or asthma-in-remission might not like stove emissions, for example. For me the possibility of avoiding a wood burner or multifuel stove would carry weight, if I was selling up and going for a narrowboat.

 

I wonder if anyone has installed one of those "radiators with an LCD picture of a real fire" on a narrowboat? 🙂

 

Edited December 21, 2023 by Matt Wardman

[Andrew Grainger]

59 minutes ago, Matt Wardman said:

I'd definitely concur that 12-month liveaboard is the extreme case, and "Part time live aboard" with some cruising in winter - as suggested by the OP - is more of a middle case.

 

I think it is interesting exploring what is possible / practical today. It's another set of possible compromises.

 

People with asthma or asthma-in-remission might not like stove emissions, for example. For me the possibility of avoiding a wood burner or multifuel stove would carry weight, if I was selling up and going for a narrowboat.

 Very interesting and useful thanks. Our current boat is 57ft with a LPG/electric wet heating system and no stove. Being a little asthmatic we certainly don’t want a stove. we liveaboard about half time fairly evenly split over the seasons. 
Lots to consider. 

[ditchcrawler]

1 hour ago, Matt Wardman said:

 

 

I like it that boatbuilders don't tell me how much insulation it has - just "highly insulated". I wonder why - perhaps because it isn't 🙃.

If there is interest, we could do a LENB thread to explore the question and other aspects further.

 

Mine when my hull arrived was as thin as a coat of paint, thankfully my hull builder got the spray foam company to come from Wales to Suffolk to recoat it. So hulls I have seen prior to lining out has been very thin a lot less than the thickness of the ribs.