Technical
Solar update
I’ve just completed a project which allows me (or anyone else for that matter) to monitor the performance of Caxton’s solar panels. This involved connecting a Raspberry Pi computer to the controller and storing the data in a MySQL database online.
It is better to view during daylight hours as the controller goes into sleep mode after dark – a bit like me!
Sniper on the roof!
OK well not actually a sniper but a Snipe 2 satellite dish. When we bought Caxton there was a single feed (LNB) satellite dish mounted on the rear bulkhead which worked very well feeding a signal to a receiver inside. At home we ditched Sky a number of years ago and bought a Humax Freesat HD receiver / recorder. It seemed to make sense to move the Humax on board and upgrade the dish to a twin LNB which is needed to provide the ability to watch one channel and record another at the same time. We don’t really watch a lot of television and what we do watch tends to be recorded so that we can watch when it suits us and of course adverts can be skipped too. We don’t follow the soaps either so we don’t have to slavishly watch day after day either.
I decided to really go for the upgrade and get a self seeking satellite dish to save any messing around with alignment when we moored in a new area. There are a number of options out there but I chose the Snipe after consulting with Caxton’s original owner. Joe fitted one to his current boat and assured me that it was a worthwhile purchase. The Snipe isn’t cheap, around £730 in this country but I bought mine from a German Ebay seller for £620.
Installation was straightforward although a little time consuming. The first thing to do is to attach the mounting plate to the roof, I chose to stick it down with a silicon gasket sealant rather than to drill and bolt it. Next I drilled a hole in the roof before feeding the cables into the electrical cupboard below. The Snipe kit includes a cable entry box to give a weatherproof cover for the cable. I left the silicon to cure overnight before resuming the installation.
The snipe has three coaxial cables, two which carry the signal to the receiver and a third which connects to the control unit. The cables are very thin which is great in the sense that they take up very little room but it means that they are difficult to push through confined spaces. I already new that the signal cables were long enough to reach the receiver and the controller was going to be mounted in the cupboard so there was only the small matter of routing the two signal cables.
What a nightmare!
First of all I had to break a piece of plywood which was boxing in pipes and cables across the rear bulkhead. The right angle under a cupboard wasn’t too bad using a piece of conduit to pull the cables through. I pulled the fridge out to pull through and then fed the cables into the cupboard under the sink. So far so good but then it all became really difficult.
Now if you’re the sort of person who thinks that narrowboat living should be a simplistic affair, look away now!
The next obstacle to overcome was the tumble drier, no problem I thought until I attempted to pull it out of its space. There isn’t enough room! It must have been positioned before either the worktop went on or the units opposite were put in place. Whatever the case, there wasn’t enough room to get it out and gain access to the back. With the next unit being a dishwasher – yes, a dishwasher! – I was facing a major difficulty. Fortunately the existing aerial cable lies in the same channel so I thought that there should be a way to pull the cables through. I taped a spare piece of wire to the existing cable and pulled towards the back of the boat. Once the end appeared under the sink cupboard, I disconnected it and taped it to the end of the snipe cable and pulled it forward. It got stuck, presumably in the bulkhead between both of the appliances. I attempted the move four or five times before giving up and heading off to Maplin. I figured that the only choice was to cut the existing two coaxial cables in the cupboard under the sink, terminate them and attach the cables from the Snipe. After returning from Maplin in Nuneaton, I attempted to pull the cable back but it was stuck and wouldn’t move in either direction. Now i was fearful of breaking the cable or pulling the plug off the end since it is not a standard thickness cable. It didn’t help that I had to keep climbing past or over the tumble drier which sat half way across the galley. Suddenly, the cable was free and I assumed that the tape securing the cables had given way but as i pulled the coax forward, the Snipe cable came with it. I had achieved what I had set out to do and my trip to Maplin had been needless. I figured then that if I could get one cable through, I could get the second through and sure enough, twenty minutes later, both cables were in place. All that remained was to bolt the dish to the mounting plate, attach the cables and connect the controller to a 12 volt power supply. Since the controller sits inside the electrical cupboard, that was one of the easier parts of the installation.
Was it worth it? Absolutely! One button on the controller provides the power and gives a choice of satellites starting with the last one tuned to. Another button press activates the GPS controlled dish which then points, in our case, to the Astra 2 satellite. When it’s time to move on, another button press moves the dish back to a flat parked position.
So far we’ve only tried the dish in two locations and we know that it still relies on “line of sight” to work but it’s a convenience thing rather than a necessity. Having said that, it is a magnificent gadget to see in action!
Power of the sun
Using solar power to create electricity is a fantastic idea but it’s not very efficient. At work I have investigated the possibility of installing solar panels on warehouse roofs many times over the years and can never manage to justify the expense. Admittedly, the payback time has improved over the years but nevertheless it still stands at around eight years in the best location. The problem is that the payback depends on government subsidies and as the panels become cheaper to buy and their efficiency improves, so the subsidies reduce and quite rightly so. After all, that subsidy is funded by everyone who pays an electricity bill with a feed in tariff applied to it. Most solar panels today have an efficiency rating of around 19% and the best (and most expensive) can achieve 26 – 28% so there is still a long way to go in their development. Whether we like it or not, the most efficient way to make electricity is in a giant gas fired power station.
On a narrowboat, electricity is produced by an alternator bolted to the engine and although it’s a reasonably efficient process when travelling, it’s a costly business to run the engine when just moored up. Until this year, our boating has consisted mainly of weekends and holidays so we would normally be travelling most days and therefore charging the batteries as we went. Now of course we are just about to embark on a six month long journey and travelling every day is not part of our plan. The idea of running the engine every day or two to charge the batteries didn’t really appeal so I decided to investigate the practicalities of a solar installation.
As usual, there seemed to be a lot of information but much of it unclear or contradictory. In the end, I think that I got to where I wanted to be in terms of sourcing the right equipment and installing it. I got a lot of good information from the Bimble Solar website although in the end only bought mounting brackets from there. The brackets are made from stainless steel and allow the panels to be tilted towards the sun if required. They also mean that the panels can go over the top of things like mushroom vents rather than require a roof area completely devoid of obstructions. An added bonus is that the panels get better airflow around them which will keep them a little cooler than they might otherwise become. Solar panels lose efficiency as they heat up which is a bit of a drawback for something which needs to be exposed to the sun to work!
The largest components are the panels themselves and I elected to go for two standard size domestic panels which I bought from Edmondson Electrical in Rugby. These panels are approximately 1m by 1.6m so on Caxton, two of them fit end to end in the roof space between the two houdini hatches. My research had led me to believe that mono crystalline panels were better than poly crystalline but I couldn’t really find out why. My first visit to Edmondson’s changed my mind and this is why. Mono crystalline cells are created using a process not to dissimilar to how you grew crystals as a child at school or at home. The silicon grows until it is large enough to be machined but there is a lot of wasted material due to the odd shapes that are created. The process for making poly crystalline cells involves melting the silicon and pouring it into a mould before letting it cool down and then machining it. This is a quicker process and less material is wasted because the solidified silicon is uniform in shape. In the early development of the solar cells, mono crystalline cells were much more efficient than their poly crystalline cousins. Today there is very little, if anything, in it. Cosmetically, the mono crystalline panels are black which makes them more appealing when bolted to the roof of a house. Poly crystalline panels have a bluish hue but that is of no consequence when mounted horizontally on the roof of a brightly painted boat. The panels that I bought are rated at 260 watts each with a voltage of 32v.
The next piece of equipment and arguably the most important piece is the controller. This converts the relatively high voltage from the panels into someting that can be used for charging a twelve volt battery bank. There are two types: PWM and MPPT, here there seems to be no doubt or contradiction, MPPT is the way to go. More expensive but it is in effect a three stage intelligent charger. Bimble sell Epever 40 amp units for just over £200 and they seem to be a reputable make. I discovered that they are made in China and that I could buy direct through Aliexpress for £160 so that is what I did. The unit arrived ten days later followed by an invoice from TNT. The covering letter said that they had paid VAT on my behalf for the import and that was £15. Their admin charge was £20 and the VAT on that was £4. All in all I ended up saving around £4 so my advice would be to just buy from Bimble Solar.
The rest of the bits required I bought from various ebay sellers but I’ll cover those in the next section which describes the installation.
Caxton has a full height cupboard which houses the inverter as well as most of the other electrical switch gear and this is just inside the rear of the cabin area. The first part of the installation was to mount the MPPT controller in the bottom of the cupboard which was straightforward enough, four screws hold it in place. I then connected the unit to the battery bank by wiring it through 16mm2 cable to the heavy duty input/output cables on the inverter. I included a 40 amp fuse to protect the cable but since the controller is rated at 40A and the cable is rated at 70A, I don’t expect to change it any time soon. The next thing was to wire the input of the controller to an isolator switch which would be connected to the solar panels. It is important to get an isolator for DC circuits rather than the more common AC circuits. I got mine from ebay rated at 25 amps. The panels have a total maximum rating of 520 W at around 70V when wired in series so the maximum current can only be 520/70 or 7.5A. After that I cut a hole in the wall panel and installed the small monitoring unit which displays the performance of the panels. Finally, I connected the optional temperature sensor before threading it through the bulkhead and into the battery box where it monitors the temperature of the battery bank.
With the control end of the installation complete it was time to mount the panels on the roof. Bimble sell a mounting kit comprising of two drills, a tap to thread the holes and some weatherproof mastic. I bought the kit but it was a waste of money. Perhaps the steel used on Caxton is special but I suspect not, the drills were only capable of managing two holes so I ended up buying more from Screwfix. The tap broke in one of the holes so I had to buy a proper tap and die set to complete the job. All in all I drilled ten holes, four brackets with two each and another two into the cupboard for the cables. The mastic provided a seal under the brackets and around the bolts as well as around the plastic box sitting over the cable entry point. Next I drilled the edges of the solar panel frames and then mounted them on to their support brackets. All that remained was to crimp plugs to the ends of the cables that I had bought from ebay and feed the cables through some conduit and into the electrical cuboard before connecting the cables to the isolator switch. The penultimate action was to connect the cables to the panels and then finally to turn the isolator switch on. Electricity flowed immediately and all that remained was to set the controller up to charge the batteries properly. This was done by disconnecting the small monitoring panel and then connecting the controller to my laptop and then running the Epever software. After that I reconnected the monitoring panel and started to observe the activity.
The question is, do they work? In the limited scope of testing, the answer is yes. They managed to keep the batteries at 100% for two weeks when we had mostly overcast days. I then ran the fridge and freezer for a week and still the panels kept the batteries at 99%. I used the laptop to monitor the state of charge over a 24 hour period and saw that after sunset the battery bank eventually dropped to 95% but by early next evening it had recovered to 99%. Bearing in mind that it is still early April, I think that this is an encouraging result. It will be interesting to see how well the system copes once we move aboard full time and increase our power usage.
I reckon that I spent just under £600 installing this system and although the prime motive was that of convenience rather than cost saving, there is a decent payback time. Caxton’s beta 43 engine consumes approximately 1.5 litres of diesel an hour and at today’s price of around £1.00 per litre it’s easy to see that by not having to run the engine for 400 hours we will save the installation cost. We won’t break even in the first year but we will at some point in 2018. This doesn’t take account of the fact that there will be less wear on the engine or the cost of servicing the engine less frequently but those are also beneficial factors. I’m hopeful that when we return to the marina next winter the panels will still produce enough energy to keep the batteries topped up without having to rely on being plugged into the mains supply.
Watch this space for regular updates.
Hacked Off!!
The blog got hacked. Why do people do this sort of stuff? The blog is a wordpress site on a shared host and has happily ticked over unmolested for the last three years. On Easter Sunday I received an email from the hosting company informing me that dues to unusually high email traffic, the hosting account was being suspended. I was able to get access to the account temporarily and could see that there were emails being generated every few minutes. I disabled all of the wordpress plugins as they seem to be the likely culprits. This stopped the emails but there was another problem, some software was generating referrals and driving traffic to the site and very quickly I exceeded my monthly bandwidth allowance resulting in another suspension. In the end I had to remove the blog from the subdomain caxton.narrowboat.us and create a fresh installation at boating.georgekennedy.co.uk and here it is. So there was no lasting damage done but it has created a lot of work to straighten everything out. There has been no loss for me and I can’t see what the hackers have to gain, maybe I am just missing the point. Anyway, if you had previously bookmarked our blog, you might want to adjust it slightly replacing “caxton” with “www”
More Expense!
One of the hidden joys of boating is the odd unexpected expense or two. Things go wrong, equipment fails, bits break off and they all have to be fixed. This happens in houses and with cars as well of course but with a boat it is different, with a boat, the cost is always eyewatering! We’ve already forked out nearly £700 for a new calorifier (hot water tank) this year and today another £300 went on a replacement water pump for the Hurricane heater. There’s a problem with the large domestic alternator which we’re hoping will be a cheap fix, if not, another four hundred quid will bite the dust.
After we moored up yesterday at Napton, I called Calcutt boats who are the UK and European agents for the Hurricane heater to see if they could take a look at the problematic unit. The result was that we would take Caxton there this afternoon. This morning, we took a walk up to the village shop at Napton, we first visited it about five years ago when it had just changed hands and what a transformation there has been since then. This once run down store is now a little treasure selling the full range of groceries and speciality foods. It’s a post office and a cafe too so well worth the ten minute walk from the canal. Once again we lunched at the Folly Inn before setting off for Calcutt, a destination that we reached just after two o’clock. After descending the top lock, we pulled on to the wharf and then sat in the sunshine as two engineers fiddled with and diagnosed the problem with the hurricane. Two hours, a new pump and three hundred pounds later, we were ready to leave. Before then, we met Barry and Sandra from the home brew boat who had pulled in for diesel and while we were waiting, passed the time of day with them.
We went back up through the top lock at Calcutt just before five o’clock and made our way back to Wigrams turn where we turned left and looked for a mooring. We found a spot, actually one of our old haunts near bridge 103 where have settled for the evening. There are tractors harvesting corn in the fields around us, the moon is almost full and we have seen a beautiful sunset.
If the price of this lifestyle is the odd bill for a few hundred quid, it must be worth it.
Service Time
It couldn’t be put off any longer, it was time to do some maintenance work. Having availed myself of the Halfords special offer on oil which gave me 10 litres and two sets of screwdrivers for forty quid (Many thanks to Sue on No Problem for highlighting that on the blog), all that remained was to get cracking.
First off I checked the bow thruster and its dedicated battery at the pointy end of Caxton, all was well but I topped the battery cells up with a little de-ionised water. At the blunt end I did the same with the starter battery and while I was there I went down the weed hatch and cleared a few bits of crap that had wound around the prop, nothing serious but it might as well be removed whilst I was in the mood.
The next job was to check and tighten the three drive belts and as I did so I made a note of the various sockets and spanners used. I’ve also made a note of the belt reference numbers and will source some spares before they break, thus avoiding extortionate chandlery prices in future.
Next up was the oil. The gearbox has a slight leak, more of a weep really, which collects in a plastic tray in the bilge so I had a pretty good idea of how much I would need to top up by. After that was done I ran the engine for ten minutes before pumping out the old engine oil. Despite the fact that there is a sump pump, it doesn’t sit high enough to accommodate a five litre bottle underneath. No matter, a bit of hose pipe and a jubilee clip soon allowed me to clear the sump of the black stuff. Removing the oil filter proved to be a bit of a challenge, I had a pair of rubber strap type wrenches for the job but the filter was on so tight that I managed to break both. Fortunately, the local branch of Screwfix is next to the marina so after a short walk I was able to remove the offending article with my new pair of oil filter pliers.
I almost managed to get away without dropping any oil in the bilge but not quite, however the small amount that did escape took very little effort to mop up. With the new filter on, it was just a matter of pouring in the new oil, running the engine for five minutes, checking for leaks and then topping up to the mark on the dipstick.
A quick check of the fuel at the bottom of the aggregator completed the service so all that was left to do was just clear away the tools and dump the rubbish and old oil.
I did mention to Sue that because of the cramped space that I have to squeeze myself into to do some of the work, our next boat (should there be one) will have a proper engine room. Her suggestion was to use child labour like they do in other countries!
Photos
Regular followers of this blog might be wondering why there are no photos in the posts. Quite simply, a combination of poor internet connections and limited mobile data means that the photos are going to have to be uploaded once we reach home.
The Contortionist returns
On Friday morning I had a call from Cox Automotive at Atherstone to tell me that I could collect the Travelpower. In the afternoon I drove there, parted with a load of money and picked up the reconditioned unit. It’s only a few miles to Market Bosworth from Cox’s so by four o’clock I was on board preparing to start work. The control box was relatively easy as had been its removal. Then it was time for the difficult bit, the generator. It must be nice and easy for Beta’s engineers marinising engines in a factory but it’s a different matter removing and replacing bits in the confines of an engine ‘ole. With spanners, sockets and screwdrivers handily placed, I lowered myself into the small space between the engine and the cabin bulkhead. The interference fit of the generator in its mounting bracket had made removal difficult but replacing it was impossible so I decided to remove the bracket and try to tap it into place with a mallet. Bent double, I managed to get it off, tap it into place and then remount it. It sounds easy but the whole process took 45 minutes and after I had extricated myself from my cramped workstation it was time to test it all. I’m pleased to say that it all worked and after an hour’s running, everything was still tight. I logged the output of the Travelpower using the mastervolt software and found that it was producing a consistent 240 volts. Cox recommend getting it serviced again in three years so hopefully I won’t be stuck down the front of the engine until then.
The on/off switch for the Travelpower is located on the front of the control box which is in the back of the cupboard below the switch panel. This makes it easy to forget to switch it off so after consulting with Mr Cox, I extended the cabling and mounted the switch outside the cupboard.
With the job complete, all that remains is for my newly acquired aches and pains to fade, we have mains power on the go in time for the Easter weekend so Sue will be able to run as many washloads as she likes! We’re hoping to make a trip to either Coventry or Atherstone.
The joy of boating is…….
…. That sudden surprise expenditure!
When we took Caxton out at Christmas, we discovered that there was a fault with the Travelpower generator. The problem only caused us to have the minor inconvenience of not being able to use the washing machine, no big deal only being out for a week. I didn’t do anything about it until the weekend just gone when it was mild enough to get into the engine room and remove the generator for inspection. As is the way with these jobs, it was a real pig to get off, even a double jointed strongman would have struggled but I persevered and eventually it was out and disconnected. Removing the control box was much easier by comparison and then today it was off to Cox Automotive at Atherstone, specialists of this parish, for a proper diagnosis.
I had hoped that it would be no more than replacement brushes or something similar. No such luck, the rotor in the generator has failed and needs to be refurbished- £340 + vat. There are some resistors in the control box which have cooked and although it may not be essential to replace them just yet, it seems pointless to ignore the problem so that will be another £180 + vat.
It will be early next week before the work is done so there won’t be any cruising this weekend, hopefully I’ll have the time to get it all back together again before the Easter weekend.
Blokey Stuff – Mastervolt
Despite the fact that we haven’t been out on Caxton, I have been checking the good ship out when possible. Four weeks ago I arrived at the marina to discover that the shore power had tripped out. In actual fact, the incoming MCB had tripped even though the one on the pontoon post hadn’t. When I reset the onboard MCB there was still no power and the display on the post showed an error. I sent a text to Chris, the marina manager who promised to investigate for me. I returned to the marina a couple of days later and met Chris who told me that there was no credit left on the meter, whatever the fault was it had managed to discharge around 99kWh. Chris topped the meter up again and all seemed well until I checked the Masterview display which showed all sorts of errors.
Caxton has a Mastervolt system on board which comprises of a Mass Combi (an inverter/ charger), a Mastershunt which monitors the batteries and a display screen. Up until this moment everything had worked well but now the display was flicking all over the place, showing alarms and suggesting that the batteries were at 25 volts!
Being a bit of a geek on the side, I decided to buy a Mastervolt USB interface rather than call for a technician and try to diagnose the problem myself. It cost me £120 but it has turned out to be a good investment. Sadly, the display had been damaged by the power surge problem but I was able to verify that the Mass Combi was unaffected. The Mastershunt needed to be reset but was otherwise alright. The beauty of the Mastervolt system is that the components are connected using CAT5 network cables so fiddling and playing with the bits is a geek’s dream.
A new Masterview Easy unit costs over £200 but I was able to buy one off Ebay for just over £60 and what’s more, being the MkII version, it can display more information than the one which had been originally installed.
I spent a happy (or sad, depending on your gender) programming the new Masterview display unit and I am happy to report that everything is back in good order again.
The geek in me is left with three projects now.
1. Can I refurbish the old Masterview display unit?
2. Can I create a new program and display on a tablet or mobile phone?
3. Can I offer my services as a Mastervolt system technician?
Obviously, I’ll report back here if I make any progress with the above.