House Battery Bank: Should we go 48 Volt?

While we wrote Going 100% electric: the β€œhouse” after Going 100% electric: the Motor we had in fact made most of the decisions around the house electrical system before we made the decision that we would go straight to an electric motor instead of the diesel.

Now we are thinking about making a change. The things prompting us to consider a change include:

  • The high cost of 48 volt battery chargers. We do need the option of charging our battery bank when in a marina or harbour (or even ashore in the boatyard). We can imagine spending sometime alongside in winter or even popping every so often just to get the batteries fully charged (the expectation of needing to live in colder climates in Winter is influenced by both Covid and Brexit which might limit our options for where we spend our time).
  • We think our house battery bank has ended up a bit small (4 x 120AH) and so are going to be needing to charge it from the Motor bank (4 x 300AH) quite often.
  • Having two battery banks at different voltages ends up creating quite a lot of extra complication.
  • With one exception (the anchor windlass) we have realised that our 12 volt usage is relatively low (LED lighting, boat instruments, water pumps).
  • While we have specified really thick cabling with big busbars and fuses, it is challenging to power 2 x 2,000 watt inverters from a 12 volt battery bank. The current that we need to safely pass is huge and this is where the vast majority of our house consumption will be (induction hobs, microwave, multi-cooker, watermaker, water heater).
  • We didn’t understand enough about how you can power 12 volt systems from a 48 volt battery bank. We thought they were too inefficient but have now realised that we either incur that inefficiency when charging a 12 volt battery bank from the 48 volt bank for all house uses OR when using a 12 volt house appliance (but not a mains powered item from a 48 volt inverter). The total losses are much smaller if we incur them only as we need the 12 volt power rather than to keep a whole batery bank charged.
  • We deliberately chose 4 batteries for the house bank that had enough output so they could be re-wired to be a 48 volt battery bank for the motor if the main bank failed. However, it would take ages to do. So a bigger 48 volt bank with two sets of 4 batteries wired in series and then the sets connected in parallel gives immediate access.

So a little maths about the issue with power over 12v cables.

P = power in watts (W)
V = voltage in volts (V)
I = current in amps (A)

Power = Current x Voltage or P = I x V

Switching it around we have I = P / V
So 4,000 watts from 12 volts = 4,000 / 12 = 333 Amps
Whereas on a 48 volt system we have 83 Amps

More amps = thicker cables and lots of care to avoid melting connections or high losses.

The disadvantages of changing from a 12 volt hour battery bank

Our current thinking

  • As we install them, we will configure all 8 batteries as a single 48 volt battery bank. This is pretty straightforward.
  • We will sell our unused 2 x 2,000 watt Victron Phoenix inverters (get in touch if you are interested).
  • We will use our Victron Orion 48 volt DC to 12 volt DC converter to power all our 12 volt appliances. We can always add extra Orion’s to run together if we need more power (eg for the electric auto-pilot)
  • It would be very expensive to add enough Orion’s to provide all the 1,500 watts at 12 volts for the windlass. So we will add a 12 volt battery close to the windlass. When the windlass isn’t being used we can charge the battery through the standard 12 volt system.
  • We will add 2 x 48 volt 3,000 watt Victon Multi-plus charger/inverters (2 of them to provide redundancy, we can run appliances with some limitations off one of them).

The Multi-plus inverters are smart. They provide mains power to the boat circuit and they automatically take that power from a shore power connection or if that isn’t available from the battery bank. When connected to shore power they automatically charge the battery bank. Two of them can put a total 70 amps into the battery bank.

We will have a 48 Volt battery bank with a total capacity of 1,680 AH (4 x 300 plus 4 x 120). Suppose we arrive at a marina with it fully depleted (ie down to 10% charge). That means we need to put in 90% of 1,680Ah which is 1,512 AH. At 70 Amps charging we are talking about 21 hours to fully recharge the battery bank (realistically we would expect many marinas to be limited to either 16A or 32A supplies so this will be a lot slower). Gradually we would expect marinas to upgrade their electric supply as the number of electric boats increases.

While there are costs to this change it does simplify a number of things, particularly with cabling and charging. All our charging goes into the one battery bank without having to switch solar panels between banks or do inefficient bank to bank charging.

It gives us much simpler use of the battery capacity as we can choose how we allocate the available power between house and motor. For example if we are not going anywhere and expect some sunny days in a while we can use all the capacity for the house. Or if we are motoring up a river to a marina all the house capacity is available for the motor.

In the long term we would expect more boat appliances to be available in 48 volt versions which will gradually reduce the need for DC to DC converters.

We haven’t made a final decision on this yet, but it does look like we are heading this way at the moment.

More safety from moving to fossil fuel free Sailing

In my post Safe, Sustainable Coffee for sailing? I made the point that using an electric filter coffee machine is safer because you do not have to pour boiling water. Especially you do not have to pour boiling water onto a tower of things resting on each other (eg V60 filter holder balanced on a mug).

What I didn’t emphasise is that this safety aspect is only possible (or at least far easier) with a switch away from fossil fuels. Many yachts are now fitting small inverters to use small mains electric gadgets. However, unless you design a higher capacity system in terms of renewable generation, batteries, wiring, inverters etc and implement it with gimbled surfaces for extra devices you are not going to be able to make the switch to an electric filter coffee machine (unless you run your engine to recharge your batteries a lot).

Unfortunately, there are few good options for making coffee without mains electrical appliances. A moka pot is probably the only option, but you don’t see many people using them with pan clamps to hold them securely on a hob at sea (and very often see them perched quite precariously on pan supports that are designed for much larger pans. Anyway they are not preference for coffee when sailing, I want a longer drink to provide warmth and comfort rather than a quick shot.

The same comes to other cooking options. An electric multi-cooker (on a gimbled tray) seems a lot safer option for cooking a stew or soup at sea (well most one pot meals) than either a pan or a stovetop pressure cooker. The advantages include:

  • they cook at a lower pressure/temperature than a traditional stovetop pressure cooker.
  • there are fewer exposed hot things to touch and handle. An advantage when cooking is done but it also means that unlike a stovetop pressure cooker or pan it can be held down in place not just clamped to avoid sliding. So should be safer in more violent motions.
  • Unlike most pans they have a securely fitted lid and don’t need to be stirred while cooking. Reduces the chance of hot food going flying around the cabin (several examples from the Vendee Globe this year).

While we don’t plan to fill the boat with lots of electric devices for cooking, these two seem to us to have significant safety benefits that have not been widely recognised. The main safety concerns that have been addressed in past regulations mainly relate to gas explosions or burning fuel.

Safe, Sustainable Coffee for sailing?

Planning for live aboard cruising on a sailing boat presents particular challenges for one of the highlights of the day – especially if you are aiming for a sustainable life. Almost everything about the environment of sailing makes coffee a challenge, particularly: Availability, Space, Power, and Safety. Clearly we need to get this sorted because otherwise I’m not fit to be around anyone else πŸ˜‰

As for our expectations. I love coffee and drink a lot, Jane much less. Although we have both worked in a CafΓ© which did include barista work we are by no means coffee snobs, so we don’t have the highest standards or expertise πŸ™‚

At home we do have a big commercial grinder (thanks to some lovely friends). We buy our coffee in bulk from TankCoffee, so get away with keeping longer than ideal to benefit from bulk buying prices by starting with great quality beans. We mostly use a Melitta Look IV Therm Timer Filter Coffee Machine. I guess that illustrates what we look for, so no hotplate (spoils the coffee) but also no manual control of temperature and no sophisticated brew cycle that includes a bloom phase.

At the moment we use a very simple plastic holder for filter paper on the boat (we take coffee we have ground at home). When camping I’ve typically used an AeroPress with a cheap Porlex hand grinder (oh look there is now an improved version II and much higher prices).

If we were to want to make Espresso coffee we would really need to have rather fresher beans than we get away with at the moment.

This video from the amazing James Hoffmann: Coffee, Climate Change & Extinction: A conversation with Dr Aaron Davis at Kew was interesting and highlights some of the challenges to coffee for the long term, meanwhile all we do, so far, is try to buy the most ethical coffee with the least big corporations involved as we can.

Availability: Getting hold of coffee and keeping it presents challenges when you are crossing oceans or cruising in remote areas.

Space: A 38 foot boat, particularly an older design has very limited storage which of course challenges high coffee standards in two key ways:
a) shortage of dry places that keep a nice even temperature for storing the coffee
b) a very small galley without much counter or cupboard space.
So that rules out a lot of coffee appliances.

Power: By sailing yacht standards we do have lots of mains electric power but the capacity is limited. That again puts constraints on the number of electric appliances.

Safety: In this video from Ryan and Sophie the dangers of making coffee on a boat were dramatically illustrated.

Our Coffee Plan

Everyone needs a coffee plan! Running out of coffee would be a very serious situation, and I don’t think the RNLI are ready to help us in this kind of emergency. So this is where we are at.

Initially we plan to stick to buying roasted beans in bulk and grinding them as needed. We should be able to carry enough for 6 months at a time without too much difficulty (we currently use between 1 and 1.5kg a month). For us that is a reasonable sweet spot between long storage between shops, quality and price. Hopefully we can buy in beans in decent quantities in most cities – one city every 6 months sounds reasonable πŸ˜‰ I admit I’m interested in exploring roasting our own beans in the future. Green Beans potentially last a lot longer (up to a year). Maybe we can fund our retirement by roasting coffee to order for the cruising community πŸ˜‰

When sailing I’m concerned that we avoid any of the (many) ways of making coffee that involve pouring boiling water or unsealed containers with boiling water in them, or free standing stacks of items that hot liquids are moving though. So that rules out all manual forms of coffee filtering, the AeroPress, French Presses and lots of others.

So it looks like a simple filter coffee machine, like we already have, where you add cold water and it puts the hot coffee straight into a non spill, unbreakable thermos flask. Our plan is to have a gimbled tray which can be used for any appliance (induction hob, coffee machine, multi-cooker) so it should be safe to make coffee when heeled or in waves.

If we add one of the higher quality, higher capacity hand grinders (needs less space, less power), then we should be good to go. These can grind to suit Espresso as well as filter machines.

We already have a number of basic thermos style travel mugs which are definitely more suited to a moving boat and drinking outside.

When it comes to making fancier coffees for use at anchor we can look at one of the manual Espresso machines such as a Flair (no power needs and they fold away for storage). There are also an increasing number of ways to froth milk without the steam wand from an Espresso machine.

I’m sure we will also carry an AeroPress as a reliable backup if the filter machine breaks, just a lot of caveats about safety if using at sea.

I’m not interested in a any of the Pod machines (Nespresso etc), while re-usable pods are now available I’ve not heard good things about the drinks they make. Anyway as I prefer a longer drink (such as a long black) you would have to add hot water to the drink.

Continuing Solar planning

Sadly, we can’t do much but plan at the moment. However, that does at least give us the opportunity to improve those plans.

In More on sustainability, I included a bit about Jimmy Cornell needing to abandon his attempt to sail around the world with zero carbon emissions. So another incentive to improve our plans.

This is what we have so far:

Wheelhouse roof

4 x 40 watt panels (total 160 watts) for the top of the wheelhouse roof. To be connected so that the two sides are in parallel reducing the impact of the considerable shading as the main boom is just above the wheelhouse.

Guardrail mounted

4 x 175 watt panels (total 700 watts) to be fitted alongside the guardrails. They will be moveable, tiltable and removable. So we can have up to 4 on either side of the boat (to catch the sun). While sailing we should be able to have 2 per side (positioned about 3/4 of the way aft), with the option to drop them to be vertical (like canvas side dodgers but with a gap for water drainage below them) for docking or if waves are a problem. But there are plenty of people sailing with these pretty permanently mounted (eg Rigging Doctor, Millennial Falcon, Sailing Project Atticus). We can also remove them and store them below in really bad weather (recognising that ours are larger and hence more windage).

We have been exploring lots of potential ways of fitting these. Quite a lot will end up depending on how our budget goes over the next few years, but we have a cheap getting us started option using lightish timber struts. Update see Simplifying guardrail solar panels.

Longer Term Plans:

By adding a solar “arch” (see below) we should have a grand total of 1460 watts. That is more than Jimmy Cornell, plus we will be able to rotate and tilt them to improve efficiency. Coupled with significantly reduced power consumption (only 2 people, wind vane steering, only one fridge, no electric winches etc) we think we are heading towards the right ballpark figure.

Solar Arch.

We have lost count of the number of design options we have been through. Here was one. It got pretty complicated as we work around all the constraints. Our fairly narrow stern, mizzen boom and need for Hydrovane self steering make the structure very challenging.

Our current thinking is to mount two 300 watt panels almost completely independent of each other (total 600 watts). Through a combination of rotating and tilting we will be able to position them for maximum efficiency while also being able to have them either clear of the mizzen sail (ie sticking out aft beyond the boat length) or safe for docking or storms (ie extending forward over the mizzen boom and aft cabin) at which point we would not be able to use the mizzen sail. They will also be removable, even at sea so that again we can stow them (probably on deck due to their size) if needed.

Our plan is to first shorten the mizzen boom as much as we can for the existing sails. Longer term we might get a new mizzen sail with a shorter foot but fully battened with a fathead sail (google images of Fathead mainsails), that would keep the boom further out of the way,

Then the implementation we hav agreed with Hydrovane puts the actual vane a little higher than normal so that it is clear of the mizzen boom and sail (thus allowing us to tack without having to touch the vane mechanism).

The solar support will start with an upright carbon fibre tube in each aft corner of the deck (or possibly just down the transom a little), these will be positioned so that they are just clear of the boom as it swings across. They will have a diagonal strut going forward and another diagonal going across the stern. There is a vast array of carbon fibre tubes available up to 54mm diameter so we have some calculations to do.

The top 500mm or so will be above the diagonal struts and will be filled with thickened epoxy. This is then a base onto which the pole for the solar panel drops. These Carbon Fibre Tubes are designed so that each size slides into the next size up. So the poles for the panels will be one size up from the fixed upright tubes. They too will have a thickened epoxy filling but leaving 500mm open to drop onto the upright tubes. Connecting the tubes this way allows the upper section to be rotated or removed. We will have a hole for a pin will allow the rotation to be locked in two places (and will also stop the top tube lifting off).

A smaller tube will be fitted horizontally to the top of the solar panel upright. Using a smaller diameter will allow us to attach it by through drilling the upright for the horizontal to fit though. The joint area will then be filled with thickened epoxy to lock everything in place. The horizontal tube will only project out on one side of the upright (like an inverted L). Using the rotation and locking pin this can be forwards or backwards from the upright. This horizontal will be approximately 3/4 of the length of one of the solar panels.

To attach the solar panel we have two slightly oversized square tubes. These are the long enough to be fitted to the solar panel (going across the width of it). They have holes drilled in the middle, with short lengths of tube (next size up from the horizontal) fixed into them so that they can slide onto the horizontal tube. This attached the solar panel and allows it to tilt.

To support this we add a smaller tube as a diagonal brace between the upright and the unsupported end of the horizontal tube. At which point it will look a like we have a pair of gallows on the boat with solar panels on top πŸ™‚

All the fixed joints will be created by smaller diameter tubes going through the larger, the smaller tubes will have smaller holes inside the joint so that when the joint area is filled with slightly thickened epoxy they get locked into place. We will also use epoxy fillets on the outside of the joints.

We will use dyneema guys to control the tilt of the panels with the option to use them to lock the rotation in other places than the locking pin allows.

To remove the panels we will use a halyard. We will rig it so that the pull is up a topping lift, that means as the upright tube comes free the whole thing won’t swing wildly about into the mast.

This give us multiple positioning options:

  • Preferred sailing option. Turning the panels aft so clear of the mizzen, with the ability to tilt them either for maximum solar efficiency or for minimal windage (compensating for the boats heel) depending on the conditions.
  • Preferred docked option. Turning the panels forward, the mizzen can’t be used but they are fully within the deck outline so not going to snag on other boats or be a hazard to people on the dock.
  • Moderately bad conditions. Assuming that you have taken the mizzen sail down, turn the panels forward and take the tilting control lines forward for maximum stability (better angle and braced to the deck rather than the support post).
  • Storm conditions expected (whether sailing, at anchor or in a marina). Lift the panels up so the uprights come off the fixed supports. Lower to the deck and secure.
  • At anchor. Rotate and tilt so the panels are as close to right angles to the sun, adjust to compensate for both the boat and the sun moving.

Safety

There are obvious concerns about having large panels relatively high in the air. However, there have now been multiple Atlantic crossings by boats similar in size to Vida with panels this size on solar arches.

We do recognise that our design is a little different due to the complications (mizzen and hydrovane). We do not think this design is possible with the typical stainless steel tubing designs. However, carbon fibre tubes can be used for a wide variety of purposes including masts and wind turbines, that support significant loads on unstayed uprights.

Unlike other solutions we have a variety of options do deal with different conditions. We are not creating a fit and forget solution but one that fits with our expectation of Active Solar Generation which we believe is a critical factor in achieving zero fossil fuels. The real potential to increase solar generation isn’t clear but a 30% increase is possible when you can angle correctly and far more if panels can be moved to avoid shading.

Wind generators

We can potentially add a similar pole support base on each side of the boat by the mizzen mast. In suitable conditions a wind generator can then be deployed. Again using the active generation principle. Wind generators are only effective in certain conditions, so why would we want the noise and windage all the time? However, they are the best option for reducing the need for a generator when we need electric power for heating while anchored in winter when there isn’t much sun.

Avoiding engineering calculation paralysis

Two recent examples have in equal measures frustrated and amused me.

In their plans for Ruby Rose 2 Nick and Terysa have oodles of calculations but they appear to be aimed at justifying fitting large diesel engines because an all electric boat isn’t possible. They seem to have totally missed what was shown to be possible in their interview with Dan and Kika from Sailing Uma.

Then there is the subscription website “Attainable Adventure Cruising, The Offshore Voyaging Reference Site” with an article in the last week “Induction Cooking For Boatsβ€”Part 1, Is It Practical?” where I joined a discussion coming from our very different approach.

Both these present a numbers based “engineering” approach to decision making about the “practicalities” of moving away from fossil fuels. Sadly due to the initial assumptions the approach almost always leads to the conclusion that renewable energy sources cannot provide enough power for either propulsion or cooking.

The approach rejects working examples because they don’t present numbers in an “acceptable” way.

Our problem with this approach is that it is simply too easy to make assumptions about what is needed and the conclusion depends far more on the assumptions than on the calculations. In both these cases the assumptions are based on the expectations and lifestyle of a couple.

Ruby Rose have assumptions about never compromising on a luxury lifestyle with every modern convenience.

John and Phyllis have decades of experience cruising in high latitudes and strong views on what is safe and seaworthy. They have a stated goal of not considering anything that has not got a 10 year history of reliability.

Both these approaches are flawed if the goal is sustainability (or if budget constraints are tight). So if your assumptions are that you need to motor for an hour at full speed, and 500 miles at cruising speed, cook for a couple of hours every day, run a water maker, washing machine, multiple fridges and freezers, electric auto pilot, video editing laptops every day then you are going to conclude that renewable energy sources can’t cope.

Cynically if you control the list of things that you want to run all the time or anytime regardless of the conditions then you can guarantee that you will never be able to manage with renewable resources (at least until the last oil well has run dry and the Netherlands has disappeared under the sea).

Yet there is another way. One that we find most often from people with limited resources.

Embrace the limitations

Or start at the other end. Start with the resources that are possible.

  • What battery bank capacity can I afford?
  • What size battery bank can I fit (size and weight)
  • How many solar panels can I fit (and afford)?
  • Is wind generation going to fit my boat, my budget, my geography?
  • Is water power generation either from regen on an electric motor or something like Watt and Sea going to work (how much time sailing at suitable speeds)

These provide the constraints. Then sustainability becomes how you live within the constraints. There are plenty of options.

  • A vegetarian or vegan diet (as recommended as a key way of reducing our carbon footprint) can reduce the cooking energy significantly (no a roast chicken cooked for several hours is not required every week, if you want it then save your energy up first, or use a solar oven)
  • Set your passage plans according to the energy you have, probably slower (but then the whole point of sailing is surely to sail)
  • Set your cruising ground according to the season and energy available and required (so you probably can’t sail sustainably into an Arctic winter which is just a constraint, like the ones the majority of people live with all the time)
  • Have food available that doesn’t need to be cooked if you are short of energy (Huel and the like)
  • Plan to use appliances when you have the energy, keep the ones that have to be on to a minimum (eg freezers, fridges, autopilots).
  • Embrace the constraints. Do you really have to be able to do the washing, make water and cook for 2 hours on the same cloudy day – if yes then why?
  • To be honest the list is endless, we have gone in just a few years from it being normal to only use an engine in harbours to expecting to motor constantly for days at a time. From no refrigeration and basic hobs to dishwashers and ovens and drinks coolers in the cockpit.

The argument that it isn’t possible to live within the constraints of renewable energy is disproved by history. It is disproved by the examples already documenting their experiences eg Sailing Uma; and Beau and Brandy.

The challenge is to our assumptions, our privilege, our expectations of luxury. The opportunity is to open ourselves to the impact our lives have on others and to stop seeing ourselves as deserving something that our actions deny for others both now and in the future.

Holiday progress day 13: yes more cockpit work

We are getting very close with the cockpit after today.

The epoxy work for the aft cockpit drains is nearly finished. After drying overnight we should have just a few little bits to fill with thickened epoxy to make sure that the lower lip if fully sealed (where it tucks under the old grp lip and flange).

With the lip bits are now fixed in place (to both the cockpit floor and to the drain area) and the area around the white skin fitting filled with epoxy so there should be nowhere for water to collect.

As you may be able to see our resin has gone a bit jelly like and so isn’t mixing as smooth as it was (don’t know if this is shelf-life or temperature or what). We are nearly at the end of a big bottle, so as it seems to still set hard we will use it up on areas where the finish isn’t too important (and hopefully ones not critical to safety).

I have managed to get both of the old drains out ready for new TruDesign skin fittings.

If we can’t finish them this holiday we will simply seal them up for the moment.

We also had a big delivery of shiny bits today (sadly FedEx left only parcel 1 of 2 so not everything).

Here is the PSS Pro dripless seal and the refurbished bronze flange it will fit to.

Here is the Aquadrive (thrust bearing and CVT that allows for the motor to be on a different alignment to the propeller shaft).

Then we have our motor mounts.

This evening we had a really nice socially distanced BBQ on the beach with the members of the NWVYC we cheated slightly as we don’t have a BBQ. So we ran a power extension cable from the boat and setup our Induction Hob on our workmate πŸ™‚ It was very effective πŸ™‚ Anyway it was lovely to see people and chat about boat refits (and other topics were permitted).

Hoping dry weather continues so we can get the cockpit watertight.

Going 100% electric: the “house”

I recently detailed where we are at with the Electric Motor, now for the domestic “House” side.

The House power supply

I have started building the battery box which will sit above the motor and motor batteries in the motor compartment.

We have 4 x 120AH Lithium (LiFePo4) batteries from KS Energy KS-LT120B. These have Bluetooth BMS’ which I have been able to connect to from a Raspberry Pi (so one day will be able to monitor and control from the integrated navigation system). Their high continuous current rating of 160 Amp and 30 seconds surge at 250 Amp means they are easily able to power our inverters. It also means that we could rewire them in series to replace the motor batteries if we needed to.

These batteries are going to be connected in parallel so they act as a 12 volt, 480AH bank. This is one decision we agonised over. An alternative would be to have a 48volt house battery bank (and even have a common battery bank for the motor and house – such as Sailing Uma have). The biggest advantage of a 48 volt system would have been for the inverters. However, there are also disadvantages, particularly if you want to add additional battery capacity (you need to add four 12 volt batteries at a time).

Powerful 12 volt inverters require a lot of current, they therefore need very thick cables and short cable runs. Ours are going to be very short and so on balance we have gone for the simplicity of running everything on the house side at 12 volts.

So our batteries are connected in parallel using a massive 60mm x 6mm tinned copper busbar. We will be using very short 95mm2 cables to connect the batteries to the busbar. All 8 cables will be the same length. This form of connection is one of recommended ways (simplest of them in our opinion) of making sure that the battery use is balanced equally across the batteries.

From the battery box +ve busbar we will have doubled 95mm2 cables to a fuse. Then doubled 95mm2 cables to a shunt (used so that the Victron battery monitor sees everything). Then again doubled 95mm2 cables to the main battery switch. Finally the doubled 95mm2 cables go to a +ve secondary busbar at the forward end of the battery box.

From the battery box -ve busbar we will have doubled 95mm2 cables direct to the -ve secondary busbar at the forward end of the battery box.

The reason for doubling the 95mm2 cables is twofold. First, our inverters could potentially draw more current than one 95mm2 cable can carry. Second, the inverters are very sensitive to any voltage drop over the cable (it can cause fluctuations which can damage the batteries). By doubling the cables and keeping the lengths very short we should avoid both problems.

We will have 4 connections from each secondary busbar. All of them will have circuit breakers or fuses on the positive and all of them will have 95mm2 cables to the circuit breakers/fuses.

  • Inverter 1: a Victron 12V inverter giving up to 2000 watts (95mm2 cable)
  • Inverter 2: a Victron 12V inverter giving up to 2000 watts (95mm2 cable)
  • Lofrans Tigres Horizontal Anchor Windlass windlass 12v connected via 70mm2 cables (thicker than the 50mm2 specified by the manufacturer)
  • Distribution busbar for Main 12volt switch panel (busbars situated above the corridor to the aft cabin, switch panels on the bulkhead above the entrance to the corridor)

The 230volt AC systems

The Victron inverters get connected together into a single mains supply. So we have a 230V 4000watt mains supply via a standard circuit breaker box. The main purpose of having so much 230 volt power is the galley. In the galley we have

  • 2 x single induction hobs (max 2000watts each)
  • Microwave/combination oven/grill (max approx 1000watts)
  • Multi-cooker (max 900watts)

And no doubt we will be adding coffee machine and a few other gadgets.

So we will be able to run any 2 of these devices at full power at the same time (and to be safe we won’t run both hobs on full power at the same time).

Beyond the galley we have

  • 230volt water heater to supply sinks and shower
  • Device like our current laptops which only have 230 volt power connectors.
  • Two wall infrared panel heaters.
  • Power tools (most of them are now cordless but the batteries are charged from 230volts)
  • One day in the future a 230volt watermaker

Our electric outboard motor for the dinghy has a 12volt charger as well as a 230volt one.

4000 watts should be plenty with some simple house rules

  • only one cooking device while using the windlass (why would anyone be cooking when you are either raising or lowering the anchor?)
  • if using two cooking devices then turn off most other mains devices (possibly via the circuit breaker?)

The 12volt DC systems

These are mostly very normal for boats with lights, instruments, electric autopilot (we mainly want to use a windvane anyway), fridge (not planning a freezer), windlass (a lot of current but not for very long).

However, we are also going to be building our navigation, entertainment and office systems around 12volt Raspberry Pi computers and 12 volt screens. This will include WiFi to our phones etc. We will be fitting a hi power/long range 3G/4G antenna that will make it’s connection available via WiFi to everything else.

The Raspberry Pi’s will be used for navigation (we have a touch screen for the cockpit) with OpenCPN as well as for general use (everything from NetFlix to general office to video editing) on a TV screen in the saloon.

We will be using a SignalK server to connect the Raspberry Pi systems to marine instruments (AIS, Radar, WindSpeed/Direction etc). Anyway that is a whole lot of other posts.

Capacity

While it is perfectly ok for us to plan the system so that we can deliver 4000watts for cooking at full power on two hobs or run all these other devices the fact is that we still have a battery bank with limited capacity.

Here we admit there are a lot of unknowns and variables. However, we think that being able to monitor our battery use very accurately will allow us to modify our behaviour to suit the available battery charge (eg no hot showers or minimise cooking power use).

The next key part of the picture is how we recharge our batteries, both house and motor banks). That will have to be a separate blog post.

Sustaining Electrics

We have had lots of comments that salt water and electrics are not compatible. We also see lots of YouTube channels who find that their electronics (laptops, hard disks, cameras etc) do not last well in salt water environments.

This shouldn’t come as a surprise. So what are we doing about it?

First, we need to recognise that Salt Water and Diesel are also not compatible. Also that diesel engines still need some electrics (very few modern diesel engines can be started by hand).

Second, there is a lot that can be done to help electrics survive better and to be more sustainable in our use of them. So here are a few things we are doing that particularly relate to the electric motor.

  1. Keep salt water out of the boat.
    1. Reduce the number of holes in the boat. We are down to 2 seacocks which are for the cockpit drains and so there is no opening from them into the interior of the boat.
    2. Change the traditional stuffing box to seal the propeller shaft with a modern dripless seal. The stuffing boxes always leak a little, right next to the motor which is clearly a bad thing.
  2. Actively dry the air, we will be fitting and electric dehumidifier into the motor compartment so that the air used to cool the motor will be dryer. The model we are looking at (Ecor Pro Dryboat 12) removes the moisture in an warm, damp exhaust to the outside (so we don’t need to have a water drain inside). A side effect is warm, dry air that can be used to warm the cabin, dry clothes etc.
  3. Box in the motor. While not fully sealing the motor (it is air cooled so needs air flow) we will make sure that it isn’t directly open to the bilge and that the air into the motor compartment comes from drier parts of the boat (such as the aft cabin which is far from the entrance and from wet clothes lockers). The compartment will be fully sealed from the cockpit locker where wet ropes, fenders etc will be stored. Also fully sealed from the galley where we create steam.
  4. Keep other water away from the motor compartment. So no plumbing at all. No water pump, no hot water tank etc.

We are also considering sustainability when it comes to other electronics such as used for navigation, general computing, entertainment etc.

Here our intention is to avoid integrated proprietary solutions in favour of low cost, open solutions. Also to use wireless communications where possible.

So our key platform will be Raspberry Pi single board computers. These do not require fans, can be installed in fully waterproof cases and run off 5Volt DC so are easy to power from our battery banks. They can be used for navigation (using OpenCPN), communication between sensors (such as wind speed, boat speed, AIS etc using SignalK as well as wired connections), entertainment (video etc), work (office software, video editing etc etc).

All the software is free and open source which is always far more sustainable than closed proprietary solutions that companies can stop supporting (or the companies can disappear). Even if you are not a programmer you still benefit from this.

Waterproof screens are now widely available and replacement screens can be bought anywhere (anything with an hdmi connection will work). That compares to replacement screen needing to be bought from B&G or Garmin or Apple.

As Raspberry Pi computers are cheap (the most powerful, more than we need is Β£74) and can be used for so many tasks, we can have several meaning we gain redundancy.

More and more sailors are switching from the very expensive dedicated units such as from B&G, Garmin, Raymarine and instead using the phone, iPad or tablet. However, these are generally not very waterproof and as they are all in one units they are expensive to replace.

Instead we can have a “dumb” but waterproof screen and keep the brains (the Raspberry Pi) separate, away from the elements. If there is a failure we haven’t lost the whole unit bit can easily replace just the broken part.

The open source element also allows a great deal of integration For example I can write code to access our Batteries Management systems over bluetooth from our Raspberry Pi (and make it available to the boat management system) without needing to wait for our unknown brand to be supported by the navigation system supplier. Others have connected sensors for temperature, humidity and much more.

There are a number of new sensors for sailing becoming available eg wind sensors from both OpenWind and Calypso that are solar powered and wireless. Both can be connected to Raspberry Pi systems. This should prove more reliable that systems requiring wires up the mast for power and data signals.

Whilst the (very expensive) integrated systems from B&G etc are very sophisticated they also tie you into an ecosystem that does not have sustainability at it’s core. To gain that you need to have more control yourself which is what the OpenSource approach gives.

Plus neither we nor the planet can afford to keep replacing Macbook laptop computers every year or two.

Cabin Refurbishment: Part 2 Approaches

Continuing from Cabin Refurbishment: Part 1 the story so far and what is delaying us.

I’m going to generalise and say there are four main approaches to the interior of older yachts.

The Minimal: don’t change anything, don’t fix anything that isn’t a problem for you. Probably coupled with gradually reducing expectations of where you will go. This is where Vida had been for a number of years which included 2 years out of the water. Inside the layout and furnishings were essentially original with nearly all original equipment some of which didn’t work and some of which had become dangerous (eg gas installation, paraffin heater and especially it’s jerrycan). As is obvious from the speed we have taken stuff out this is clearly not something we are comfortable given our goal of preparing the boat for a live-aboard retirement.

The Restoration: There are lots of people who do this absolutely beautifully, spending hours and hours sanding and varnishing the interior woodwork, replacing like for like with beautiful care so you can’t see the joins. This is not us either, partly because we don’t really like that traditional look of so much dark wood, partly because we want to be sailing not sanding and varnishing, partly because we think things have moved on from what was a traditional yacht in the 1970’s.

The Functional: Do what is needed, very often on a low budget, so that you can get sailing. Often something by younger people who take on a project boat. Whilst Vida is definitely a “project” boat we are not yet ready to go off live-aboard cruising (which is what we see for a few years time in retirement) so we have time to do things to a more comfortable standard befitting our advanced years πŸ˜‰

The Radical: a complete refit including remodelling and modernising. Obviously we are doing this on the technical side (composting toilets, removing seacocks, fossil fuel free etc). Clearly this can be done to a wide variety of standards from exquisite to utilitarian. Our preferences are more to the pragmatic and functional end of the spectrum. We are not interested in a wow factor of beautiful joinery or a “luxury” presentation so much as everything working awesomely and being very low on maintenance.

Obviously, these are very simplistic generalisations and most people will combine the different options for different parts of the boat (a forecabin might get ignored for a long time unless it is where you sleep in which case it might be first priority.

We choose to put ourselves towards the more extreme end of “The Radical” approach for a number of reasons.

  • It makes the technical stuff easier and quicker if we are not trying to make restoration as easy as possible. We save ourselves a lot of effort if we can remove things to improve access without worrying about restoring them or keeping it functional while the work is happening (so for example it hasn’t been an issue for us to have 9 or more holes in the bottom for months and months)
  • by spending some money we can save a whole lot of time (eg by buying new sinks for a new worktop rather than trying to rescue the old ones), our present lives mean we are quite time poor at present.
  • We believe that expectations and products have changed a great deal in the last 40 years. Examples include
    • what we expect to cook and eat when sailing or living aboard. Making a cup of tea or instant coffee and adding water to dehydrated food is only expected by weight watching racers. We want real food and given that our diet is almost entirely meat free we want to be able to prepare meals from fresh ingredients wherever possible. Our budget and anchorage preferences means we want and expect to cook ourselves nearly all the time rather than eat at restaurants. This affects storage, food preparation areas and galley equipment.0
    • Navigation, communications and entertainment are a whole different world with significant impacts on every part of the interior (the Internet, mobile phones, batteries, electronic charts, LED’s, TV’s, video etc)
    • Our expectations of comfort (warmth, dryness, depth of mattress, materials, ventilation)
    • Where people expect to cruise to. Yes the world but also the North West Passage was impossible for a yacht and many places would not have occurred to ordinary people, they were for the amazing adventurers only. So now we can watch people going to Greenland or the Norwegian Arctic Circle and think we could do the same.

What we are still realising is that our approach means that when we think of refurbishing the interior we are actually looking at rather more radical re-workings of the space than we had expected or realised. That seems a good place to finish this post and leave you hanging on for part 3 πŸ™‚

Continued in Cabin Refurbishment: Part 3 Interior Theme and Style

Plans for anchoring

The need.

Once we start cruising our plan is to spend the vast majority of time at anchor when we are not sailing.

Partly this is to save money πŸ™‚ For example, the nearest marinas to us at Conwy currently cost about Β£35 a night or Β£215 a week. A visitors mooring is Β£18.50 per night. Paying those prices would soon add up to very large part of our budget.

However, more than just the money is the experience. We much prefer being at anchor in a quiet river or bay than being tied up in a marina (good examples we have visited before in Cornwall would include the River Yealm and the River Fal as well as bays such as Studland).

So a lot of what we are planning is to give us the maximum freedom to be at anchor as much as possible. By being fossil fuel free we won’t need to go to marinas or harbours for fuel or energy. By having a watermaker we won’t need to go there to fill up with water. By fitting a high quality 4G antenna (up high) we will improve the mobile signal to give good Internet access more of the time, without needing to go somewhere for WiFi. As public WiFi becomes more common we can also fit a long range antenna for that too.

So for shopping, getting rid of rubbish and leisure we don’t need to be in a marina or harbour, we can use the dinghy. Probably the main use of marinas will be when we want to leave the boat unattended for family visits or whatever.

Knowing that we want to be anchored a lot of the time is one thing. However, there are very different challenges for this depending on where you are in the world (and very different costs).

In the UK the key challenge with anchoring is that much of the coastline (particularly the South Coast) is very crowded with many rivers full of marinas or moorings. This reduces the availability of places left to anchor. So often you need to anchor in a more exposed anchorage where you might need to move depending on the weather (particularly wind direction) as there are few available places sheltered enough from all directions.

In other places (like the Bahamas) there are millions of places to anchor (although again you will need to move around due to wind or swell). Other places have fewer places to anchor and more marinas (eg some parts of the Mediterranean).

What we need, therefore, is a high reliability, easy to use anchoring setup that we can trust and which enables us to easily move between anchorages then anchoring becomes the default, obvious, no-brainer choice..

That means, as with many areas, we are making plans that are significantly different to where Vida is at the moment and different to many of the boats that you typically see when walking around a harbour or marina – there you often see yachts with anchors that are tiny and very rarely used.

The challenge

Our requirements are quite different to what was the norm when Vida was built in the 1976/77. Then anchors were normally lifted on deck and stored in an anchor locker. That wasn’t too difficult as the size was limited by the capabilities of a manual windlass.

Over the years expectations, fashion and technology have all changed. Electric windlasses are now common (allowing heavier anchors and longer chain without a very fit and strong crew). There have also been really significant improvements in anchor design during the last 40 years. As a result most boats store their anchor permanently in the bow roller, ready for use and to save lifting it around.

But our bow roller was not designed to store an anchor when at sea, despite that the old CQR Anchor was clearly often stored there (and as a result has damaged the bow roller). Now our anchor locker isn’t big enough for a modern anchor (as they typically don’t pivot and lie flat). Because the windlass is in the anchor locker it requires an extra roller to change the angle of the incoming chain so that it is right for the windlass.

Old CQR anchor in the locker. Note the extra roller in the middle which lines the chain up properly for the windlass.

In the next picture you can see the bow roller and how the chain has damaged the route into the locker.

We obviously get a lot of water into the anchor locker. Despite the little drain holes it collects a puddle of rainwater and if a wave comes on deck that big slot will allow a lot into the locker. Both these have presumably contributed to the rust attack on the windlass.

When we bought Vida the chain was in very poor condition and hence wasn’t able to neatly pile into the chain locker which is under the v-berth in the forecabin.

We were looking for ways to replace the roller in the bow fitting (not only bits chipped off by the anchor but also suffering from UV degradation), but it is difficult as there is no side access to the pin.

Ok so that is the challenge. What are we planning?

The Plan

This plan has evolved a few times πŸ™‚

We start with the anchor hardware. After reading lots of tests and opinion pieces we have chosen a SPADE Anchor. It is one of the “New Generation” anchor designs (about 20 years old). I don’t think I’ve seen it outside the top 5 in any test (in one test they broke the test equipment with a SPADE Anchor).

It does disassemble into two pieces which can be convenient. The shaft is actually 3D (a hollow triangular cross section) which means it is incredibly resistant to sideways forces (such as when the boat swings round to pull in the opposite direction due to a tide change).

The pointed tip is actually hollow and filled with lead so that it is very nose heavy which helps it dig in reliably.

By just about every table of anchor sizes I have gone up one size. So this is a 30kg anchor which means that, at least in theory, it should be adequate for a full storm, if not a hurricane. It won’t be our only anchor but we are following the advice that a big anchor in your locker does nothing so make it your normal anchor.

If I wasn’t going to have a SPADE anchor then I’d probably go for the quite similar and very new Mantus M2 (which unlike their earlier anchor does not have a roll bar).

To go with this anchor I have what should be top quality Italian chain from Lofrans. 80 metres of 10mm, again oversized. I’ll add some line to the end of that should we visit the pacific where there can be some very deep anchorages. This chain alone should be good for pretty bad conditions in up to around 15m or 50 feet depth of water.

This anchor and chain is going to be far too heavy for us to recover by hand (except we would find a way to use the main sheet winches or a block and tackle in an emergency). So we have an Electric Windlass to fit.

This was really what set the limit for the anchor and chain. This was the most powerful windlass that was sensible in price and which used 12 volt. So that stopped me getting the next size anchor.

Now we come to the changes that we need to make.

The bow roller is not suitable for this anchor. It will not hold it securely when sailing. It also won’t be able to fully self launch (so if you let some chain out the anchor will just sit there until you tilt it a bit by hand). We have been thinking about a lot of options in terms of custom alterations to what we have. We might still go down that route for cost reasons. However, what we want to end up with is essentially a Mantus Bow Roller with their Anchor Mate. By removing the right hand roller and side of our existing bow roller we can fit the Mantus Bow Roller on top of the flat base of our existing bow roller.

Then the next set of connected changes are somewhat bigger (and won’t necessarily happen before we launch for our first sailing season). They are designed to address a number of problems:

  • New windlass isn’t going to fit in the existing locker using the same hole to drop the chain below.
  • We don’t really want a new electric windlass to be sitting in a pool of water and to have slat water sloshing in and taking a while to drain.
  • We want a more direct line route for the chain from the windlass to the stored anchor and bow roller.
  • We need more space for the chain and we want it further aft (back) as it is heavy.
  • We want to fit a removable inner forestay for our storm jib and need a strong-point to attach it to.
  • We love that many newer boat designs have a watertight bulkhead inside the bow so that if you hit something and get a crack or hole right in the front of the boat there is a chance that the leak will be contained behind the watertight bulkhead and you won’t sink.

So the plan (today) is to remove the lid of the anchor locker and cut out the forward section of it’s the floor. Then we will remove the interior woodwork of the v-berth to provide access.

We will then fit a crash bulkhead in several sections all the way from the deck to the bottom aft section of the anchor chain locker. This will be chunky plywood, coated in epoxy, attached on all edges to the hull and deck using thickened epoxy fillets and then glassfibre cloth with epoxy resin. It will have enough watertight inspection hatches in it, that all parts of the hull can be accessed in an emergency. The remaining part of the anchor locker floor will be joined to the new bulkhead for strength and watertightness.

I’m estimating that the gap between the watertight bulkhead and the V of the hull will be about 10cm, so not a large “crash box” but better than nothing.

The inside surface will have a sheet of slippery plastic (such as we have bought for our solar panel slider). So it will act as a shute for the anchor chain which will then slide neatly to the bottom of it;s locker which will be as far aft as possible.

Where the crash bulkhead attaches to the deck will be reinforced so that a chainplate can be fitted for the removable inner forestay.

The old anchor locker hatch will then be strengthened and permanently refitted as part of the solid deck. It will become the base for the new windlass which will sit on the deck (we will make a box/seat that will cover the windlass to give some weather/water protection when it isn’t being used).

We will fit a new chain pipe to go from the windlass down through the old anchor locker. From there the chain will simply slide down using the new bulkhead as a shute.

We will provide an opening door from the forecabin into what remains of the old anchor locker as useful storage.

Then we can reconfigure the forecabin. We don’t think we will have a fixed v-berth but instead 2 foldaway single berths with the option to use the cabin for stowage or with a bench for the sewing machine and a seat.

Finally, our normal anchoring style will be to use a bridle. If you just have the chain then in wind and waves as the bow lifts it can cause the boat to snatch at the anchor, as there is no stretch in the chain. This can jerk the anchor out of the sea bed and cause it to drag. There are examples of boats ending up on the rocks just due to the waves from passing ferries because this happened.

The bridle is made from a nylon, stretchy rope. It has two lengths joined as a V. The point of the V is attached to the chain and the two ends are cleated on the boat, one each side. The chain is loosened and now the springiness of the bridal protects the anchor and boat from snatching.

By using a bridle rather than a single line for anchoring and also for mooring balls we avoid any rubbing against the stored anchor (when on a mooring) or the chain (when anchored). The bridal also helps reduce the tendency for a boat to yaw from side to side when anchored.

That means we have a 2nd bow roller that will very rarely need to be used. So one day we hope to add a removable bowsprit to use for an asymmetric spinnaker or code zero sail to improve downwind and lightwind sailing speeds (and for the spinnaker to be easier to use).

While this might sound like a lot of work it isn’t too complicated and should make a huge difference to how convenient and easy anchoring is. It will make it much easier both to anchor and to raise the anchor, plus it will also improve the reliability of anchoring. Last but not least it will help considerably with safety not just around anchoring but also in strong winds (being able to have a storm jib) and if we ever hit anything. Now that we have the expensive parts (anchor, chain and windlass came to over Β£3,000) the rest is mostly wood, epoxy and time (only exception is sorting the bow roller).