So we arrived and were unpacked onto Vida just before midnight to be ready for the next Friday progress.
This picture of our saloon floor is there as motivation to get the motor compartment completed enough to install the house battery bank.
So we arrived and were unpacked onto Vida just before midnight to be ready for the next Friday progress.
This picture of our saloon floor is there as motivation to get the motor compartment completed enough to install the house battery bank.
I suppose the most significant progress is that we has a guest sleeping on board with us for the first time. Stephen, one of our sons, in our social bubble, joined us for the night. The saloon single berth got a good rating.
Today, I ended up working for the morning but Jane and Stephen took the house battery bank apart and then reassembled it with thickened epoxy as glue. They have then coated nearly all of it with epoxy and added some fillet joints to strengthen the joint between the sides and the base.
Then we spent some time going over the design and plans for the electrics.
Meanwhile, one of the lasts part of our drivetrain had arrived (the shaft from the reduction belt pulley to be connected to the propeller shaft via the Aquadrive) so we have been able to lay things out and make sure everything fits (it does – just).
I’ve had to redesign the way the electric motor rests on the engine mounts so that we can support this shaft at the propeller shaft end. So a few more bits of metal and one extra bearing are now on order.
This shows the base of the box for the motor batteries.
It is slightly oversized at present but there is just space for it and still be able to open/close the seacocks. Access to the Aquadrive (which will be partly under the battery box) will be by making the new bulkhead to the after cabin open-able (after all no carbon monoxide or diesel fumes to worry about).
The house battery bank goes above the motor and the motor battery bank.
The two inverters go on the bulkhead forward of the motor and just above it (grey bulkhead at the bottom of the previous two images).
Given how tight everything is I’m sure we are going to have to pay attention to air flows and ventilation to ensure that the motor, the motor controller and the batteries don’t overheat. However, I’m pretty confident that we are going to be able to make that work fine for most climates with passive ventilation. We will probably need to assist that with fans in the tropics (but if it is hot there should be plenty of solar power available to charge things.
The centre of gravity of the batteries has moved up a little from what I had hoped for. However, I don’t think it is very different to when the diesel tanks were full (and it doesn’t move around). Fortunately, we have saved a whole lot of weight in other places and when we switch to dyneema rigging we will save a whole load of very high up weight.
So not huge visible progress but a lot of thinking and planning will help next steps.
Well not much progress today because we nipped home last night as our old Diesel engine was being collected today. The forecast had also helped make the decision with another storm coming through.
So rain nearly all day for the time we were in Manchester, rain for the journey back to Beaumaris and rain most of the evening.
The key progress is emotional, with the sense of freedom from having an engine sitting in our trailer, waiting to be sold. As we were driving back we were remembering all the expensive work we would have had to do in order to get what was a good engine working.
In short, because everything around the engine wasn’t replaced with the new engine, we would have had large costs to get afloat with this engine and far more over time to get it to a point where it would be reliable with the many problems with the setup diesel supply (particularly water in the fuel and no way to get it out, modern problems diesel bug growing due to the use of bio-diesel and no way to get it out, old sludge in the tanks causing blockages in the pipes before the filters).
We are more and more glad that we took the plunge and decided to go fossil fuel free from the beginning rather than first fixing what we had. So we have not spent any money on fixing the diesel but all on preparing for where we believe all yachts need to be going – fossil fuel free.
Again we have been watching more YouTube videos and seeing more people having problems with diesel fuel, the old idea that diesel engines are this magical safety device because they are always reliable just isn’t the case for lots of people. Also the amount of nasty, cramped, smelly maintenance and the impact that has on sea sickness and morale needs to be acknowledged more openly in the sailing community.
Obviously, at the moment we have very little to be sure of in terms of the reliability of our electric motor system, how dependable will it be. However, from all we have studied so far we are quite confident. We will have a good installation of a brushless motor, that will be in as dry a place as possible, with potential backup batteries and tools/spares for making cables.
We have come to realise that the Rival 38 centre cockpit has a number of really good features for a reliable electric motor installation.
We are also implementing a few things they we hope are best practice to help with the reliability
Despite all that there are still some risks:
Compared to our lack of understanding of diesel engines this feels like a comfortable place to be 🙂 We think that overall we should be more reliable than diesel, better to live with and because of these be both more convenient and safer than a diesel engine while obviously being incredibly better for the planet.
A few people have been asking for product information about our electric plans. Bear in mind that this isn’t yet fully implemented and certainly not proven by us. Also that our choice is to be fossil fuel free and live with the impacts. If it means we can’t go as far or as fast, or if we have to do a lot of active management in order to be fossil fuel free then that is ok with us.
Note that we are not qualified to offer any advice, this is our own journey, learning as we go.
Finally, this isn’t a rush job. we are planning to get this sorted over a number of years. I have a minimum of 3 more years in my current appointment with extensions possible before we retire to live-aboard. Therefore we have time to get everything sorted, until then our sailing will be odd days and holidays.
We bought our motor and it’s controller in the UK from Falcon Electric. They work with electric car projects but we chose a motor that is sold in the US for yachts by Thunderstruck Motors. We couldn’t find a EU marine dealer for these motors.
We looked at many other motors. Either they were out of our price range or they were not brushless. We also like this being air-cooled as we want as few holes and as little complexity as possible. We know this might mean needing forced air ventilation for the motor compartment in hot weather, however for us that is a lot cheaper and simpler than water cooling.
We are not yet sure to what extent the controller will need programming for best performance, the devices to do this are quite expensive so not rushing to buy one. We also expect to need to add a larger cooling plate to the controller.
We are reusing the existing 3 bladed propeller (design max speed 1600 rpm). Our hope is that, rather than this being a big drag slowing us down while sailing, it will prove powerful driving the motor in regen mode. Upgrading to a folding prop that would have less drag while sailing a slow speeds while still being able to unfold for regen is a long term possibility (although expensive).
We are replacing the cutlass bearing due to normal wear and tear. The length of the propeller shaft and the position of the skeg require the propeller shaft to be taken out inwards. Having to remove the engine for this work was a motivation in switching from diesel now.
The original stuffing box had been leaking and needed a lot of work. We decided that as we want to minimise salt water near the electric motor we would replace it with a PSS Pro Dripless seal we chose this a) because it does not require a pressurised water feed (with an air cooled motor we don’t have one) b) it has a wide variety of sizes. We are re-using the flange that screws onto the stern tube that the stuffing box used to be attached to (have ground and sanded it smooth). The PSS Pro is therefore for a shaft of 1-1/4″ and a flange of 2-3/4″. We will be adding their Hy-Vent to provide water to the seal.
The propeller shaft will be connected to an Aquadrive system CVB10.10 (all the drivetrain components are being supplied by T.Norris Marine where Jonathan has been really helpful).
From the Aquadrive (via a coupling from T. Norris) we have a shaft that goes through our motor frame to an 80 tooth pulley for a 30mm wide timing belt (two bearings are fitted, one at each end of the frame). The motor frame is now at the forward end of the motor compartment so we are probably going to add an additional bearing for the shaft near to the Aquadrive (with the coupling etc there is quite a lot of weight on that end).
The motor sits above the shaft in a custom frame we have built and we have a 56 tooth timing belt on it. This reduction gear (56T to 80T) should allow the motor to run at peak torque with the propeller at design maximum speed. Given the motor is, at least in straight numbers, more powerful than the 29HP diesel with more torque available at low speeds we expect to not need to push the motor very hard. The motor can be moved up and down in the frame to tension the belt.
We bought the pulleys and timing belt from Bearing Boys, the stainless steel bearings from Simply Bearings, the Stainless steel for the frame from Metals4U and all the bolts from Accu. See various posts about the motor frame.
We have 4 engine mounts coming from T.Norris.
This means we should have few alignment issues for the motor and as the thrust is taken by the Aquadrive the motor should be free to float on it’s mounts which will reduce vibration and noise.
We are running the motor with a 48 volt battery bank (we decided we did not want to go for a higher voltage as then there are safety issues and also you need so many batteries in the bank).
We are building this bank from four KS Energy KS-LT300B 12V 300Ah LiFePo4 batteries. So 4 x 300Ah is 1200Ah. We chose them as being cheap, open about the technology and high density. It should be a lot simpler to wire just 4 batteries together rather than a larger number of smaller batteries (and was cheaper).
This battery bank will fit above the shaft just aft of the motor frame, forward of the aquadrive. It will be 2 layers of 2 batteries. as a 2×2 block. This keeps weight low and central with short wiring runs.
The batteries will be encased in an epoxy coated plywood box for protection.
We don’t have space to add additional batteries to this bank. However, in an (slow) emergency our house bank could be rewired as a replacement motor battery bank (by changing from parallel to series connection).
Our very rough estimate is about 1 hour at close to hull speed and about a day at slow speed (2 or 3 knots). Hopefully up to about 20 miles.
I’ll cover cabling in a later post. We are making our own cables and have the proper crimp tool. For efficiency and reliability we are using thicker cabling than is required. There will be a shunt (for measuring battery bank). There will be a shut off switch and a fuse. We will be fitting 3 Victron battery balancers (as they recommend for a bank of 4).
That is all I can think if for the moment. Have I missed out anything useful?
Our process for designing the electric motor compartment has had to be somewhat adaptable. We started from knowing nothing and so it has been a constant process of learning and then changing our plans.
The work over the last two weeks (Stuffing box flange is off, Yanmar Diesel 3JH5E for sale and Friday progress #21) has been a catalyst for some more changes. We now have a much clearer understanding of how all the parts between the motor and the propeller fit together. We also have a much better idea of what we need to fit (and many thanks to Tristan for his comments on our post Staycation Electric Motor Progress which got us rethinking our drivetrain).
So we are now close to deciding upon a PSS Pro Shaft Seal to keep the water from coming into the boat through the stern tube. We like this dripless seal as we shouldn’t need to provide a raw water supply to lubricate it. That is good because as our motor is air cooled we don’t have any raw (salt) water to divert into the seal. Some brands require 4 litres per minute which would mean installing both an extra seacock and a pump.
The challenge of providing water lubrication to the dripless seal isn’t just that we would need to provide it when the motor is running but that we would also need to provide it when sailing and using the spinning propeller to generate electricity using the regen feature.
So the PSS Pro shaft seal allows you to provide an air vented hose if your speed will be less than 12 knots (if we ever reach 12 knots it will be a short lived and no doubt terrifying moment!). However, if we find that water lubrication is required to reduce wear when running in regen mode for days at a time, then we can add a seacock salt water inlet and connect it directly to the seal without needing a pump.
The PSS Pro shaft seal is also available with a wider range of support for propeller shaft and stern tube flange sizes. We hope/plan to reuse the flange that used to hold the stuffing box, it is a larger diameter than would otherwise be the case and most dripless seals can’t cope with that.
So that is all good 🙂 The only downside is that the PSS Pro Shaft Seal is a bit longer than many of the solutions.
That brings us to then next piece of the puzzle which is where Tristan was so helpful. Our initial plans used thrust bearings within the motor frame to absorb the push and pull from the propeller. These have two grub screws that pass the thrust from the propeller shaft onto the motor frame and then that gets passed through the motor mounts to actually move the boat.
It turned out that as a very basic and cheap solution it was flawed. Two grub screws are not very much when it comes to transmitting the thrust generated by a 40hp motor spinning a propeller ar 1600 rpm to move 9 tons of boat. Also if the motor mounts need to transmit all the thrust to the boat they can’t be very flexible and so they won’t absorb much vibration.
So we are adding an Aquadrive to the drivetrain. This helps us in several ways. The propeller shaft ends at the Aquadrive which is fixed in perfect alignment with the cutlass bearing. So vibration and wear is minimised. The Aquadrive then passes all the thrust directly to the boat, so no thrust is acting on the motor which can therefore be mounted on much softer mounts so less vibration is passed onto the boat. Plus the connection from the Aquadrive allows for a lot of freedom in alignment for the motor requiring a less accurate installation.
Apart from the cost of the Aquadrive (nearly £1,000) this is all good. However, the impact on our layout is that the Aquadrive is over 250mm long.
With the PSS Pro Shaft Seal and the Aquadrive our motor needs to be moved forward so much that instead fitting the motor batteries (2 rows of 2) in front of the motor there is barely space for one.
So, we think we are switching things around. We will move the motor to the forward end of the motor compartment, a longer shaft will connect the motor frame to the Aquadrive. The motor batteries will then go aft of the motor above the shaft and Aquadrive (it raises them by about 200mm).
We will probably move the house bank batteries to above the motor to keep the weight distribution approximately the same fore and aft. The centre of gravity will be a bit higher although we think still lower than with the diesel and full tanks.
We have not tried to fully plan where all the electrical items will go (motor controller, and inverters are the biggest) yet.
The plan is to build from the bottom up. So
Fortunately, while the list is long the uncertainty is getting less. The biggest unknown is now how well the default program settings of the motor controller will work. Will we need to hire or buy the tool to reprogram it? Within that the biggest questions are about the regen and we won’t be able to know much about that until we are actually sailing.
So quite happy with all this :-).
So we have come of age 😉 21 today. Not too bad, we are still a month away from owning Vida for a year and we were unable to visit for nearly 4 months due to the lockdown.
We arrived late last night (slightly delayed by a poorly signposted diversion). We had to sneak in quietly, as another couple from the NWVYC were asleep in their motorcaravan, in the carpark 🙂 So just the essentials to carry to and up onto the boat at 10:45pm.
This time that included one of our Natures Head Composting Toilets. We took it home last time as it was getting full and we decided to continue to avoid using any shared facilities, so took it home to empty. Again Composting Toilets prove to be by far the best toilet during a Pandemic. No capacity limit. No need to use anyone else’s facilities.
Anyway, after a good sleep we got stuck into our first task. Removing the Cutlass Bearing. Really the last key piece that needs to be removed (so it can be replaced with a new one) in order to progress with the electric motor installation. This is the part closest to the propeller, it is a bronze sleeve with rubber insert that slips inside the stern tube that is built into the boat.
So I had bought these bits.
A 1m long 24mm diameter threaded rod. To go on the inside end a lock nut then two washers, one with a 24mm hole to fit snugly and then one with the right outside diameter to fit inside the stern tube but not inside the cutlass bearing. So this gets pushed in from inside the boat until the threaded rod appears and the washer is snug against the inside end of the cutlass bearing.
On the outside I have a 63.5mm stainless steel tube that goes around the end of the stern tube to push against the keel. Then a huge 70mm diameter washer and another nut.
On site I used a hole saw so that I had a piece of wood to protect the keep from the stainless tube.
Here you can see the outside nearly ready to go.
It proved to be a really hard task, we tried tightening the outside nut (had to file flats onto the threaded rod so we could use a spanner to stop it moving). Got it really tight but no movement.
Tried using our short section of propeller shaft and a hammer from the inside to knock it out. No movement.
Tried to cut the cutlass bearing lengthways with the Dremmel. Managed to cut a lot out but still it didn’t move.
Then rather than hit the propeller shaft with a hammer I used the shaft itself as a sliding hammer down the stern tube. It worked!!! Took until about 2:30pm but finally we managed to get it out.
This is the sterntube without a cutlass bearing.
This is the Cutlass Bearing, you can see where I had cut it and trimmed it with the Dremmel to try to free it.
With that done we could get on with other jobs.
First up was more cleaning of the old cockpit locker and diesel engine bay. After several hours it is now mostly clean enough for sanding and painting.
After working on part of the cleaning together I moved onto the glass windows of the wheelhouse. We have noticed a few leaks and wanted to fix those and check their condition.
The corrosion wasn’t too bad. The seals were pretty rubbish though and several of the screws rather loose. I cleaned and refitted using a neoprene strip 6mm thick. We can plan something better for the future now we know what is there.
Last job of the day was to fit the first two uprights that will become the sides of the motor and battery compartment. We wanted to add some additional strength to support the cockpit, particularly on the port side where there is a footwell for when you are steering. Plus we need uprights to fasten the sides that separate the motor space from the cockpit locker on one side and the corridor on the other.
These will be epoxy coated and fixed in place, more will added when we are sure where the motor mounts will go.
The new space for the motor and batteries is going to be a lot narrower than the old. So we can extra space in the cockpit locker and in the corridor to the aft cabin.
I’ve set them both vertical which turns out to nearly perfectly line up from the engine bearers to the flange that the cockpit floor bolts to. Now these are in place I’ll be able to remove the old corridor side which is going to make access much easier.
It is now horrible outside, the wind has got up and it has been raining hard for 3 hours. Yet we have left the cockpit floor and cockpit locker lid off to continue to air them out (yet again a significant improvement in the smell). So good that we have a wheelhouse above). You can see how much cleaner they look. Once they are painted it will make such a difference!
Eventually the cockpit floor is going to be bolted down more permanently (because we don’t need to take it out to fit an electric motor) with two new, bigger, drains fitted in the rear corners. Until then it does provide lots of light and makes it easier to get the larger timber in.
As we move to boxing in the cockpit locker we will need to build a ladder, probably on the aft bulkhead in order to get in and out.
Next a good sleep, a lie in and then back home to work.
Today we got our Yanmar Diesel engine off the boat. Now ready to sell. The motivation to remove it and go fossil fuel free now rather than later was due to the original fuel tanks and fuel system rather than the replacement engine. It has less than 400 hours on it. So get in touch for a ready to go engine.
Meanwhile we have our cockpit back 😊 No oil or fuel leaks, just the dry sawdust from building the support frame and cover.
In my earlier post Stuffing box flange is off! we achieved the job that has been worrying me most during lockdown. So with that done we spent the rest of this extra day off clearing more debris from the diesel engine and preparing for the electric motor.
This is the stern tube where it emerges from the back of the keel (after we removed all the paint). This is the same tube that, on the inside, we removed the stuffing box flange from. So it is a bronze tube about 1m long fibreglassed into the structure of the boat. The propeller shaft runs through it.
After help from the Rival Owners Association with think the 3 holes, in a line, are from something fitted in the past to cut ropes that would otherwise get caught around the propeller.
The single hole is matched with one on the other side and these should have grub screws in them to hold the cutlass bearing in place.
This is the cutlass bearing. It is a bronze tube about 20cm long that fits inside the stern tube. It contains a rubber bearing with grooves cut in it. This is what the propeller shaft turns in. The grooves allow water in as a lubricant and for cooling.
It needs replacing and we managed to get the rubber insert out but not it’s bronze tube. It seems that we will have to make a couple of lengthwise cuts in the cutlass bronze tube so that we can get it out. Then the new one should just slip in. H’mm, we will see how easy that is.
Then we made some more holes in the cockpit. Top, semi circular is where the holder for the old engine gear lever/throttle was. We will take it home and prep it for the new tiny electric throttle.
The rectangle below that is from the autopilot which we have removed for cleaning and to get easier access to all that wiring.
Below that a round hole and a square hole were from two vents, we think they were for the fridge compressor. We will be blocking them up.
The rough, round hole on the left is from the manual bilge pump. We are taking it home to service, we think it will be fine, it just needs a new plastic ring on the outside as the current one was broken. All the pipes for the bilge pump will be new and routes differently so that we have access to the skin fitting where they exit the boat (we will have it a bit higher too and it will have a proper valve on it).
To do these jobs we removed both the cockpit locker and the cockpit floor for light and access. Jane did some cleaning, to get rid of the diesel stains where we have removed the fuel tank from the cockpit locker. It is now so deep only her head pokes out from it. Steps are going to be needed, at the moment we climb across the empty engine room from the corridor on the left of this picture.
This is looking from the corridor across the engine bay to the area Jane was cleaning. It looks very different. Before the whole area was as dark as the darkest part in this picture. When we have finished cleaning it will be sanded and painted to look pristine. Then a new vertical bulkhead (“wall”) will separate this locker from the electric motor room.
Meanwhile I cut the big piece of wood and fibreglass out from the side of the corridor. It was the support for the fuel tank (and an edge to stop the tank slipping into the corridor. Yet more saving of weight and taking out smell (untreated wood soaking up diesel for 42 years, yuck!).
That big chunk came from the left of the floorboard in the next picture.
In the bottom left of the picture you can see a cut out in the bulkhead which was for the fuel tank tap. This is the bulkhead at the aft end of the chart table which you can see in the picture. We are having a smaller chart table so that you sit facing forward (back leaning against this bulkhead). So we are going to trim the width of the bulkhead to match that tap cutout. Another step towards making the corridor to our cabin wider and easier.
We have now measured and we should be able to store two bike frames (with wheels taken off) in this space to the side of the corridor. We will probably hang them from hooks.
The right side of the corridor as you look in this picture will also move as we don’t need as much space or sound insulation for the electric motor.
Finally, we have been able to make lots of progress around the boatyard. Here I’m partway through removing the storage box we built around it while storing it in the cockpit since we lifted it out in February (see Diesel engine is out. Zero fossil fuel cruising on the way). We hadn’t expected it to be stored there so long. Tomorrow, the yard are going to life it out and down to the ground. Then we can sell it 🙂
We were also able to sort a few things with the other people who work around here. Steve is going to clear away the stainless steel and old diesel and he has sold the rigid dinghy that came with Vida for us.
Trevor is preparing to fit the new toerail (it will look a bit like an escalator handrail), before lockdown Gary got the preparation done by cleaning and filling the joint that the toerail covers with special flexible epoxy resin. This will be a lovely job to have finished as it was in progress a year ago when we bought Vida.
Only after we removed the autopilot and came below did we realise that this has left a big gap to be filled between the galley and the cockpit locker. Planning the rewiring is quite a big job as our electrical system is going to be so different, plus the switch panel is moving to the other side of the boat. We are intending to fit plastic tubes as conduit for all the wiring so that it is possible to pull new wires through in the future. However, we have both 240volt AC and 12volt DC to do and they need to be kept separate.
This has been worrying me for a long time. The last bolt was stuck.
But today I managed to drill the bolt out despite really tight access. I couldn’t get the drill in straight so used the Dremel with it’s flexible extension.
This allows us to sort out the, rather critical, detail of getting the propeller shaft to go from the motor on the inside of the boat to the propeller on the outside and spin without water getting into the boat around it 😊
It is all beautifully engineered bronze. As soon as all the bolts were removed the flange unscrewed perfectly from the threaded tube that is moulded in.
Next we will look at the outside end where there is a cutlass bearing.
Then we have to see if we can get a dripless seal that will fit around the tube of the flange. If not we will need to get a new custom made bronze flange with narrower tube.
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.
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 £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.