Proposed new accessible electric narrowboat.

[IanD]

1 hour ago, Matt Wardman said:

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.

 

 

I suspect your numbers are rather optimistic for real narrowboats in real life...

 

There was discussion in another thread about the power needed for frost protection:

 

https://www.canalworld.net/forums/index.php?/topic/120178-overwintering-heating-control/page/3/#comment-3009651

 

"To give some numbers on how much heat/power is needed for frost protection, in the last week the diesel boiler on my boat (set to come on at 4.5C) has run for a total of 6 hours (it comes on in bursts about 20mins long each); working back from the amount of fuel used, the average electrical heater power needed would have been something like 500W (12kWh/day). But that's the average over a week, the coldest day it ran for 1 3/4 hours which was about double that (1kW average=24kWh/day). This suggests that if you want to put electric heaters in for frost protection, you need at least 1kW, probably more if you want to protect against exceptionally cold weather. The dual 750W heaters used by @cuthound look about right... 🙂 "

 

That's just to keep the internal temperature at 4.5C, which turned out to be about 1kW average on a cold November day (subzero outside), and would need to be maybe 1.5kW on an exceptionally cold day, which suggests you need about 1kW to maintain a 5C temperature difference between inside and outside -- as I said, this is on a 60' boat which is probably as well insulated and draught-free with as little free ventilation as is practical (gas-free). Which means you need heating rated at something like 4kW to keep it warm in the middle of winter, which not coincidentally is the kind of CH/stove rating which is normally recommended for a narrowboat this size.

 

 

 

[David Mack]

11 hours ago, David Mack said:

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

 

4 hours ago, Matt Wardman said:

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

For 10mm plywood lining + 25mm of isanocyanurate that gives a U value of 0.67 W/m2k, or 0.36 W/m2k with 50mm. That compares with the Building Regulations requirement for a new build house of 0.18 W/m2K for walls and 0.11 W/m2K for roofs. So 25mm of sprayfoam loses 4-6 times as much heat per square metre as Building Regs require. So even allowing for the much smaller area of wall/roof there is still going to be significant heat loss with the sort of insulation thickness you can achieve on a narrow boat. And then add to that the impact of single glazed windows with aluminium, non thermally-broken frames...

[blackrose]

15 minutes ago, David Mack said:

 

And then add to that the impact of single glazed windows with aluminium, non thermally-broken frames...

 

....no common exterior walls shared with other occupied residences (ok some detached houses have that too), floating out on the water exposed to the wind whereas many houses have other houses nearby acting as wind breaks, and having a much greater surface area to volume ratio on a boat which means you're losing heat at a faster rate than a house in the first place irrespective of the insulation.

Edited December 22, 2023 by blackrose

[Matt Wardman]

11 hours ago, David Mack said:

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

...

 

For 10mm plywood lining + 25mm of isanocyanurate that gives a U value of 0.67 W/m2k, or 0.36 W/m2k with 50mm. That compares with the Building Regulations requirement for a new build house of 0.18 W/m2K for walls and 0.11 W/m2K for roofs. So 25mm of sprayfoam loses 4-6 times as much heat per square metre as Building Regs require. So even allowing for the much smaller area of wall/roof there is still going to be significant heat loss with the sort of insulation thickness you can achieve on a narrow boat. And then add to that the impact of single glazed windows with aluminium, non thermally-broken frames...

 

Great comment. As I see it in a narrowboat space, we are trading off 2 (or maybe 3) scarce resources - width of the space given to either living space, width given to insulation, and power input required to heat it (this last then feeds into u-value, type of insulation, type of power eg battery vs diesel vs gas, and then constraints around eg battery size or whether fumes can be tolerated).

 

Exploring the compromises, and allowing for 12mm of panel, 4mm of steel, and a perhaps slightly generous 25mm of rubbing strip (or whatever the correct word is), with 25mm of insulation (I) each side giving U-value (U) of 0.67 we get a living space (LV) width of 6'4" to 6'5" on a 6'10" hull boat width. Or, as alternatives:

 

1 - 25mm insulation gives U-value 0.67 and LV width of 6'4".

2 - 50mm insulation gives U-value 0.36 and LV width of 6'2".

3 - 75mm insulation gives U-value 0.25 and LV width of 6'0".

4 - 100mm insulation gives U-value 0.19 and LV width of 5'10".

So where's your sweet spot for your own circumstances?

In my head I think I might personally be willing to lose an extra 3" of LV (ie option 2 and a half) and maybe go for a slightly longer boat (up to 57ft from 52ft say?) as a trade off for a further 50-60% reduction in heating costs / power, or even option 3, and the need to use a genny or fossil fuel stove a whole lot less. For me it would probably be for environmental and health reasons.

 

We begin to get a feel for possibilities if eg we wanted to go as electric as possible for domestic or propulsion power, or if the cost of diesel doubled, or if we wanted to live aboard in winter, or if it was decided that inland boats be subject to similar emissions regulations as motor vehicles on roads.

 

This is a simplified model of just one aspect, ignoring for example air leakage and the cold spots that are windows and doors (we can talk about those later), and condensation and drying washing, and heat from dogs, and there are umpteen other things to explore.

 

On insulation materials I think spray PIR foam is the only game in town for hulls, and spray or slab PIR for renovations, perhaps with Aerogel sticky-back blanket for covering gaps with multifoil as a fall back. ISTM that the possibles are EPS (expanded polystyrene) and Rockwool (or something less itchy to use), or Aerogel blanket. Slightly different perhaps for underfloor, depending on how damp it gets.

Rockwool and EPS are twice as thick as PIR for the same performance. Aerogel is 5-10x as expensive for not much more performance. And based on numbers from the Fit Out Pontoon (*) in Nottingham, the cost of spraying some more is a lot less per amount for the extra, and cost seems to be disproportionately in job setup not material cost. And anything not sprayed requires meticulous attention to detail to be as effective as possible.

 

* https://www.thefitoutpontoon.co.uk/hull-integral-parts/insulation/

 

Edited December 22, 2023 by Matt Wardman

[IanD]

19 minutes ago, Matt Wardman said:

 

Great comment. As I see it in a narrowboat space, we are trading off 2 (or maybe 3) scarce resources - width of the space given to either living space, width given to insulation, and power input required to heat it (this last then feeds into u-value, type of insulation, type of power eg battery vs diesel vs gas, and then constraints around eg battery size or whether fumes can be tolerated).

 

Exploring the compromises, and allowing for 12mm of panel, 4mm of steel, and a perhaps slightly generous 25mm of rubbing strip (or whatever the correct word is), with 25mm of insulation (I) each side giving U-value (U) of 0.67 we get a living space (LV) width of 6'4" to 6'5" on a 6'10" hull boat width. Or, as alternatives:

 

1 - 25mm insulation gives U-value 0.67 and LV width of 6'4".

2 - 50mm insulation gives U-value 0.36 and LV width of 6'2".

3 - 75mm insulation gives U-value 0.25 and LV width of 6'0".

4 - 100mm insulation gives U-value 0.19 and LV width of 5'10".

So where's your sweet spot for your own circumstances?

I think I might personally be willing to lose 5" of LV (ie option 2 and a half) and maybe go for a 10% longer boat (up to 57ft from 52ft say) as a trade off for a 60% reduction in heating costs and the need to use a genny or gas stove a whole lot less. For me it would probably be for environmental and health reasons.

 

We begin to get a feel for possibilities if eg we wanted to go as electric as possible for domestic or propulsion power, or if the cost of diesel doubled, or if we wanted to live aboard in winter, or if it was decided that inland boats be subject to similar emissions regulations as motor vehicles on roads.

 

This is a simplified model of just one aspect, ignoring for example air leakage and the cold spots that are windows and doors, and there are umpteen other things to explore.

 

On insulation materials I think spray PIR foam is the only game in town for hulls, and spray or slab PIR for renovations, perhaps with Aerogel sticky-back blanket for covering gaps. ISTM that the possibles are EPS (expanded polystyrene) and Rockwool (or something less itchy to use), or Aerogel blanket. Slightly different perhaps for underfloor, depending on how damp it gets.

Rockwool and EPS are twice as thick as PIR for the same performance. Aerogel is 5-10x as expensive for not much more performance. And based on numbers from the Fit Out Pontoon (*) in Nottingham, the cost of spraying some more is a lot less for the extra and cost seems mostly to be in setup not material. And anything not sprayed requires meticulous attention to detail.

 

* https://www.thefitoutpontoon.co.uk/hull-integral-parts/insulation/

 

 

IIRC my boat is 6'1"/185cm wide internally (not onboard so can't measure it), and has a couple of inches of sprayfoam insulation. As you say there are other less-well-insulated areas like floor, portholes/windows, and then there are draughts through the free-air ventilation required by BSS regulations -- so halving the heat conduction through the walls/roof won't halve the energy needed to keep the boat warm.

 

The basic problem is that narrowboats are smaller/longer/thinner (bigger surface/volume ratio) and more poorly insulated than houses, have great difficulty using heat pumps, don't have as much roof area for solar panels, and aren't always plugged in to (partly-renewable) mains power -- and none of this is going to change any time soon, or indeed ever.

 

Which means that though it is perfectly possible to live in a well-designed house without burning anything, it's not possible on a narrowboat out on the cut except in restricted circumstances (e.g. summer, not cruising much, in a marina), and certainly not all year round unless plugged in.

Edited December 22, 2023 by IanD

[Matt Wardman]

5 minutes ago, IanD said:

As you say there are other less-well-insulated areas like floor, portholes/windows, and then there are draughts through the free-air ventilation required by BSS regulations -- so halving the heat conduction through the walls/roof won't halve the energy needed to keep the boat warm.

 

Yep - excellent point that form factor is key in making it more difficult, and I'd suggest it's a game of marginal gains in multiple aspects - and seeing what that adds up to. Being a bear of little brain, I'm thinking about one aspect at a time.

 

Do you happen to know of a u-value for a double glazed narrowboat window with a thermal break? For normal (house) glazing, single glazed is about 5.2, normal 2G is something like 1.6 with a best-on-market of around 1.0, and 3G can go as low as about 0.7.  No one seems to have published one that I can find for narrowboat 2G.

 

On heatpumps, what do you think of this one (for example), which heats, cools and dehumidifies, and has the gubbins all inside the heated space, and dimensions of 98x49x16.5cm? Heating / cooling power is ~1.7kw, power consumption is ~0.7kw.

https://www.nationalheatershops.co.uk/p/unico-air-8hp/   

[David Mack]

51 minutes ago, Matt Wardman said:

1 - 25mm insulation gives U-value 0.67 and LV width of 6'4".

2 - 50mm insulation gives U-value 0.36 and LV width of 6'2".

3 - 75mm insulation gives U-value 0.25 and LV width of 6'0".

4 - 100mm insulation gives U-value 0.19 and LV width of 5'10".

So where's your sweet spot for your own circumstances?

But the issue isn't so much the available living space width within the hull, it is the reduced width of the cabin part that impacts much more on the look, feel and sheer convenience of the living space. A narrow boat cabin with a reasonable amount of tumbledown might measure about 5 ft across the roof. Your option 4 would reduce the internal width at ceiling height down to 4'4", and that would seem very narrow, especially in situations like

a side corridor past a bathroom.

Of course that would be less of an issue on those boats with near vertical cabin sides, but such craft look pig-ugly, as well is being mainly responsible for the square cutouts one so often sees on the offside of arched bridges.

[IanD]

1 hour ago, Matt Wardman said:

 

Yep - excellent point that form factor is key in making it more difficult, and I'd suggest it's a game of marginal gains in multiple aspects - and seeing what that adds up to. Being a bear of little brain, I'm thinking about one aspect at a time.

 

Do you happen to know of a u-value for a double glazed narrowboat window with a thermal break? For normal (house) glazing, single glazed is about 5.2, normal 2G is something like 1.6 with a best-on-market of around 1.0, and 3G can go as low as about 0.7.  No one seems to have published one that I can find for narrowboat 2G.

 

On heatpumps, what do you think of this one (for example), which heats, cools and dehumidifies, and has the gubbins all inside the heated space, and dimensions of 98x49x16.5cm? Heating / cooling power is ~1.7kw, power consumption is ~0.7kw.

https://www.nationalheatershops.co.uk/p/unico-air-8hp/   

 

Narrowboat double-glazing will be nowhere near as good as household, the space between the panes is much smaller and the frames are less well insulated even with a thermal break.

 

You'd need at least two of those heatpumps for a narrowboat, and possibly three -- note that they'll be less efficient when it's cold outside (measured at +7C) which is when you really need them for heating. And I don't think those noise levels count as "silent", similar ones I've heard make a fair bit of noise especially on full power -- which again, is what you need when it's cold.

 

And the problem remains that -- like the Frigomar marine one I mentioned -- they consume about 1kW when they're running, which would be a lot of the time when it's cold, so at least 10kWh/day and could be double that when it's really cold. You're not going to get this power from solar panels even in summer (maybe 5kWh/day average on a 45' boat) and almost nothing in winter (<<1kWh/day) so where is the power going to come from?

 

Not to mention what you'll need to run the other appliances on board, including electric cooking if you go gas-free. Idle power consumption of everything on an all-electric boat like mine (including inverter, MPPTs, DC-DC, Cerbo, router...) is typically around 100W (2.4kWh/day) when moored/plugged-in *and doing nothing* like it is now, and you have to add whatever energy you use when on board (cooking, fridge, lights, TV, laptop, washer, kettle, toaster, microwave...) on top of this. Even if you're not moving at all, this could easily double the energy use, obviously this depends on what you do but another 100W average isn't that much.

 

So solar in summer will just about keep up with domestic power use and a bit of cruising, depending on size of boat -- your problem is that a 45' narrowboat has limited roof space, about half what a full-length boat has. In winter, no chance.

 

Unless you spend most of your time plugged in with battery bank power used for short cruises (up to 2 days?) or only use the boat in summer and don't move much, you're going to need an onboard generator, which means burning fuel. That's not just me saying that, it's the finding of pretty much everyone with an electric/hybrid boat.

Edited December 22, 2023 by IanD

[Up-Side-Down]

6 minutes ago, IanD said:

 

Narrowboat double-glazing will be nowhere near as good as household, the space between the panes is much smaller and the frames are less well insulated even with a thernal break.

 

You'd need at least two of those heatpumps for a narrowboat, and possibly three -- note that they'll be less efficient when it's cold outside (measured at +7C) which is when you really need them for heating. And I don't think those noise levels count as "silent", similar ones I've heard make a fair bit of noise esecially on full power -- which again, is what you need when it's cold.

 

And the problem remains that -- like the Frigomar marine one I mentioned -- they consume about 1kW when they're running, which would be a lot of the time when it's cold, so at least 10kWh/day and could be double that when it's really cold. You're not going to get this power from solar panels even in summer (maybe 5kWh/day average on a 45' boat) and almost nothing in winter (<<1kWh/day) so where is the power going to come from?

 

Not to mention what you'll need to run the other appliances on board, including electric cooking if you go gas-free. Idle power consumption of everything on an all-electric boat like mine (including inverter, MPPTs, DC-DC, Cerbo, router...) is typically around 100W (2.4kWh/day) when moored/plugged-in *and doing nothing* like it is now, and you have to add whatever energy you use when on board (cooking, lights, TV, laptop, washer, kettle, toaster, microwave...) on top of this. Even if you're not moving at all, this could easily double the energy use, obviously this depends on what you do but another 100W average isn't that much.

 

So solar in summer will just about keep up with domestic power use and a bit of cruising, depending on size of boat -- your problem is that a 45' narrowboat has limited roof space, about half what a full-length boat has. In winter, no chance.

 

Unless you spend most of your time plugged in with battery bank power used for short cruises (up to 2 days?) or only use the boat in summer and don't move much, you're going to need an onboard generator, which means burning fuel. That's not just me saying that, it's the finding of pretty much everyone with an electric/hybrid boat.

Let's say that all your heating, cooking and hot water came from 90% carbon neutral HVO, as a starting point in winter ........ (oh and we could envisage a brave new world where surplus renewable leccy was used to {inefficiently} produce hydrogen to manufacture the HVO, thereby making it almost 100% carbon neutral) ......

[Guest]

Hi had a quick squizz at this .. unsure but if you are starting a not for profit accessible boat and have any questions please let me know. We operate one .. a pioneer multi III not a canal boat ... www.floatability.co.uk x

[Alan de Enfield]

3 minutes ago, MrshappyH said:

Hi had a quick squizz at this .. unsure but if you are starting a not for profit accessible boat and have any questions please let me know. We operate one .. a pioneer multi III not a canal boat ... www.floatability.co.uk x

 

Not quite sure that that would meet the specification of NOT having a petrol / diesel engine and being able to power all cooking and heating via electricity generated from solar panels and, to be used as a liveaboard (beds / shower / toilet etc).

 

 

[Guest]

No ? It wasn't supposed to ? It was more about why he was doing it ? Setting up a not for profit ? Then if he has questions he can ask about that. It's very relevant.

The pioneer is our boat -  Incase you didn't quite understand... I was letting him know that we DONT have a canal boat but we DO have a not for profit you see ...

[IanD]

34 minutes ago, Up-Side-Down said:

Let's say that all your heating, cooking and hot water came from 90% carbon neutral HVO, as a starting point in winter ........ (oh and we could envisage a brave new world where surplus renewable leccy was used to {inefficiently} produce hydrogen to manufacture the HVO, thereby making it almost 100% carbon neutral) ......

Which is where I'd like to go, if only HVO was easily available on the canals -- which it might be in future, but isn't right now... 😞

 

Still means "burning stuff" though, with a generator and CH boiler fuelled by HVO, which was what the OP was trying to avoid -- but realistically can't... 😉

[Up-Side-Down]

55 minutes ago, IanD said:

Which is where I'd like to go, if only HVO was easily available on the canals -- which it might be in future, but isn't right now... 😞

 

Still means "burning stuff" though, with a generator and CH boiler fuelled by HVO, which was what the OP was trying to avoid -- but realistically can't... 😉

Off-grid, fossil-free and not burning stuff is a real challenge for us all but I think, potentially, marginally easier for those living on boats. But it does involve compromises, giving up stuff and accepting an element of inconvenience. As we're all different (and so are our circumstances) we each play with balancing a slightly different equation. The fact that, in our different ways, we're having a crack at it is the key thing in my mind.

[magnetman]

I really like burning wood in a fire to keep warm in winter. 

 

 

Big pile of dead hawthorn and dead ash to be burned over christmas. 

 

I would find a Boat with no fire a bit claustrophobic not that I suffer from any phobias. 

 

 

[Up-Side-Down]

Just now, magnetman said:

I really like burning wood in a fire to keep warm in winter. 

 

 

I think most of us do. It's probably deeply embedded in our DNA! There just happens to be a big 'HOWEVER' that sooner or later we'll have to come to terms with. And that will be a struggle ... a big one ....

[magnetman]

Yes I think people probably need to stop driving cars, traveling abroad and using diesel powered Boats for unnecessary movements. 

 

I stopped doing all these some time ago. 

 

 

The heating by burning things is the last one to go. 

 

I can see an A380 coming out of Heathrow right now. 

 

Would prefer clear skies. 

[Up-Side-Down]

1 minute ago, magnetman said:

Yes I think people probably need to stop driving cars, traveling abroad and using diesel powered Boats for unnecessary movements. 

 

I stopped doing all these some time ago. 

 

 

That's certainly a damned good starting point. In fact I wouldn't mind pretty much finishing there!

[magnetman]

You don't have to like me, just -be- like me and the world will be saved to survive another day. 

 

I'm not selling you anything by the way. 

 

 

[IanD]

17 minutes ago, Up-Side-Down said:

Off-grid, fossil-free and not burning stuff is a real challenge for us all but I think, potentially, marginally easier for those living on boats. But it does involve compromises, giving up stuff and accepting an element of inconvenience. As we're all different (and so are our circumstances) we each play with balancing a slightly different equation. The fact that, in our different ways, we're having a crack at it is the key thing in my mind.

I'd say the opposite -- being off-grid, fossil-free and not burning stuff is *way* easier in a suitably-built house than on a boat, especially a narrowboat. Far easier to insulate and keep warm (e.g. Passivhaus), far easier to get lots of solar on the roof, far easier to use a heat pump (air or ground source).

 

Nothing wrong with trying to do it on a boat, but the numbers are heavily stacked against you without *some* energy source like HVO -- unless you're plugged in and in a marina all the time, which isn't really boating... 😉

Edited December 22, 2023 by IanD

[Up-Side-Down]

4 minutes ago, IanD said:

I'd say the opposite -- being off-grid, fossil-free and not burning stuff is *way* easier in a suitably-built house than on a boat, especially a narrowboat. Far easier to insulate and keep warm (e.g. Passivhaus), far easier to get lots of solar on the roof, far easier to use a heat pump (air or ground source).

 

Nothing wrong with trying to do it on a boat, but the numbers are heavily stacked against you without *some* energy source like HVO -- unless you're plugged in and in a marina all the time, which isn't really boating... 😉

From the boat perspective, when you boil it down to basics, HVO is pivotal ...

[magnetman]

11 minutes ago, IanD said:

.... which isn't really boating... 

Wood can be good if its boating you want 

 

 

 

[IanD]

1 minute ago, magnetman said:

Wood can be good if its boating you want 

 

 

 

Great film. Inefficient steamers use enormous quantities of fuel though, ask @DHutch, so not very eco-friendly are they? And if they burn loads of wood, that also means truly massive PM2.5 emissions... 😞

[magnetman]

Oh I know. 

 

Its terrible how people treat the planet so badly. All those big superyachts which take 25 road tankers to fill up with Diesel. 

 

I was really shocked how people don't seem to care at all. 

 

Still at least there is light around the corner. 

 

 

[Alan de Enfield]

1 hour ago, MrshappyH said:

No ? It wasn't supposed to ? It was more about why he was doing it ? Setting up a not for profit ? Then if he has questions he can ask about that. It's very relevant.

The pioneer is our boat -  Incase you didn't quite understand... I was letting him know that we DONT have a canal boat but we DO have a not for profit you see ...

 

As the OP explained at the start of the thread it is for personal use as a cruising / liveaboard boat, which must be totally 'carbon based fuels free'.

The accessibility aspect is to suit their personal circumstances if needed as they 'age'.

 

Quote :

 

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.