Jambo

Getting close now but I'm a bit confused by the isolator switches and so have a possibly stupid question... I've found a reasonably priced 300A 12V battery isolator switch which will hopefully do for between the Outback and the batteries but I'm looking at 16A isolator switches for between the panels and the Outback and they all see to be rated at different voltages. Does it not matter as long as the rated voltage of the switch is greater than the Voc of my panels (about 75V)?

Steve Marriage of Marriage Joinery in Uxbridge (http://www.marriagejoinery.co.uk/) recently painted our boat and did an excellent job.

There was a good discussion about this last winter: http://www.canalworld.net/forums/index.php?showtopic=51616

Each to their own

The reason I went with Bedazzled is that they have some lamps that could be described as extra warm white i.e. 2700K, close to incandescent colour temperatures. The ones that you find on ebay (and indeed on Bedazzled) listed as 'warm white' are generally rated at colour temperatures of around 3000K+ and give way too cool a light for day to day use (fine for the kitchen or engine room where starker light is useful, but not for the living room imo). Given the fact that incandescent replacement costs over the lifetime of an LED lamp alone will be greater than £10 and the diesel savings will be many times that, I think it's worth it. Doubtless you can pick up cheaper ones on ebay but in general it's a case of YMMV. You pays your money...

No idea if they're referring to the same kind of repeaters linked to above but this page on the ofcom website suggests they're illegal: http://consumers.ofcom.org.uk/2012/11/mobile-repeaters/ Another possible solution is to ditch the iphone and go for a phone which has an external antenna port. I'm using a Samsung Galaxy S2 as my boat wifi phone and it works a treat with a magnetic external aerial on my roof with the cable coming down through a mushroom vent. I bought a patch lead from http://telcoantennas.com.au (the only people who seem to sell them) and looking at their website there are similar (non passive) patch leads that I guess also plug into external antenna sockets for some LG, Motorolla, Samsung and Sony phones. I can't vouch for the passive patch leads though, I've heard that they don't do much if anything. ETA: Just checked out that boatersphone website and they sell very similar looking patch leads to the one that I bought (and they probably work out to about the same price once shipping from Australia is factored in). ETA 2: You should be able to pick up a second hand Galaxy S2 pretty cheaply now

I think you have a superfluous 'h' in there Dean which confuses what you've written slightly.

Pine cones work really well.

I agree with your second point wrt freezers. Still not convinced by the first though! It might make a difference if it's a fridge that's opened and shut a great deal but under normal usage I don't see it making a great difference. No harm in doing it though and you get the added benefit of having plenty of cold water available on hot days

The first one is leaning towards myth I'm afraid. The energy required to cool down air is tiny so any saving will be very small. To cool down 1 litre of air by 1 degree takes 1.2J of energy, to cool down 1 litre of water by 1 degree takes over 4,000J The second one's interesting though. If you added litre bottles of water e.g. at 4 or 5 degrees below your fridge temperature then that should help reduce the need for the fridge compressor to run by a meaningful amount.

I'm assuming they're trying to cut their electricity demand and a cool box in a cold space has zero demand and performs really quite well.

If anyone is interested in the magnet approach then http://www.first4magnets.com has a dazzling array.

Be aware that modern fridges and freezers are not designed to operate in low temperature environments. I believe the problem is more to do with freezers than fridges: http://www.which.co.uk/home-and-garden/kitchen/guides/best-freezers-for-your-garage/ http://www.ukwhitegoods.co.uk/help/buying-advice/installation-advice/2793-fridges-a-freezers-in-garages-or-outhouses.html During winter you could consider switching off the fridge completely and simply using a cool box in a cold space - the insulation maintains a relatively even temperature and should reduce the chance of food freezing.

This is true, but I'll take it. Especially when the alternative is burning diesel in a generator or engine at... 30% efficiency? The key of course is to drive your electricity demand down as far as possible, but being able to satisfy that demand as far into winter as possible without running the generator is quite important to me.

Looking at the PVGIS calculator, and just considering inclination, the annual difference in generation you get between flat panels and panels inclined at 38 degrees (the optimum inclination for London latitudes) the difference is about a 4% increase in generation across the year. But from November to January you get a 30% increase and from October to February you get a 25% increase. Just for fun, if you had fully automated two axis tracking you'd get 41% greater generation across the year with a 68% increase November to January and a 60% increase October to February but I don't think Julynian is going to spend his whole year up on his roof shuffling his panels round to follow the sun... Thankfully technology is catching up and soon he'll be able to buy robots to do this for him (video)...

This is a good point. Might come in useful to have a little bit of extra length to play with. Cheers. Will check when I get back to the boat but that sounds like the way to do it. 2. Hmm yes I think you're right. I'm not actually on the boat at the moment as it's in dock having work done to it so I haven't been able to do the final measurements. I've been thinking about it this evening and it might be closer to 8m. But either way I think it makes sense to go for 6mm2 to reduce the losses. 3. I see they do a 125A fuse so I'll go with that. 4. This is what I was wondering. Will fit something. Cheers all! Happy to hear further comments if anyone wants to pitch in. I'll also post the list of odds and sods I buy to make this installation happen for future reference for others who want to do this.

Thanks Matty! Julynian my understanding is that the higher the voltage of the array the better - as long as it's within the limits of your controller. At a wild guess (and my electronics knowledge is very shaky) I would say that if you operate with a lower voltage you'll have a higher current and therefore have higher I2R losses? I couldn't wire all 4 in series as it would be bumping up against the 150V limit voltage of the FM80. I could wire all 4 in parallel but the voltage would be lower so I'd get bigger losses. So I've settled for a compromise of wiring each pair of panels in series and then wiring the two pairs to the FM80 in parallel. I hadn't come across the pigtails but was planning on using MC4 branch connectors (such as this) which will allow me to plug two MC4 connectors into one cable.

After much faffing with getting racking made that will tilt our panels we will shortly be in a position to go ahead and fit the panels and wire them up (hurrah!). I've been mining this forum and the internet for information about how to do the wiring and have created a diagram and description of my approach. I would be very grateful if anyone with knowledge of solar systems could take the time to have a look and tell me where I'm going wrong or where it could be made better. Below are the wiring diagrams and a description of the setup. At the end are a few questions that I still have about it. I've gone for a comparatively large installation of 1kW of PV because I'm keen to get as far into winter as possible on PV. Thanks! Wiring Diagrams Panel Layout: Four 245W Sharp panels will be arranged along the boat's centreline running from the stern hatch to around the level of the kitchen side hatch. The panels will be mounted on racking which allows approximately 35 degrees of inclination either side. Cables will run down through a cable gland through a hole in the roof under the rearmost panel into the engine room. Panel Wiring: 2 pairs of Sharp ND-R245A5 panels connected in series (with each pair connected in parallel). Wiring 4 panels in series would give a Voc at STC (standard test conditions, 25°C) of 149.2V but the FlexMax FM80 has a limit voltage of 150V (which would be exceeded at temperatures below 24°C). Wiring the panels in two pairs gives a Voc of 74.6V at STC and the Vmax of the FM80 will not be exceeded at any temperature. Isc for the Sharp panels is 6.96A so the array’s Isc will be 13.92A. The Outback FM80 can take a maximum current of 64A. The wires connecting the panels to the FM80 will be 4mm2. Engine Room Wiring: The FM80 will be mounted to a board which will be glued to the engine room's forward bulkhead. The board will be mounted directly above the boat's leisure batteries. The panel wires will come down from the engine room ceiling to a 16A DC isolation switch mounted on the board and then into the +ve and -ve PV terminals in the FM80. 35mm2 wires will run from the FM80's +ve and -ve battery terminals with a 100A inline MEGA fuse on the +ve wire mounted close to the battery. Remaining questions: - If I have an isolation switch between the panels and FM80 do I need one between the FM80 and the batteries? I've seen wiring diagrams for grid-tied PV systems and they all have it but I haven't seen many wiring diagrams for battery systems so not sure if this is needed (or is it just good practice?). - What is the best way of connecting the 35mm2 wires to the battery terminals given that some fairly chunky wires running to the charger/inverter are already attached? I was thinking of fitting battery terminal extenders. - My three leisure batteries are connected in parallel, can I simply connect to the +ve and –ve terminals of one of the batteries? - Is panel earthing necessary? (or even possible in a boat??)

Cheers. I was just checking out those MEGA fuses. Looks like they will do the job quite nicely.

Do you use breakers in place of an isolator switch? The isolator switches are coming in at about £35+ so it would be nice to find a cheaper alternative. Also can you or smileypete link to inline fuses that you would recommend? I'm using an FM80 and 35mm2 cable so I guess I'd be after ~100A

Has anyone tried ECoal? http://www.coals2u.co.uk/ecoal-25kg-prepacked I'm keen to keep our carbon emissions down as far as possible and according to the manufacturers of this product the biomass is waste olive stones and chaff so it's pretty sustainable biomass. But how does it burn?

Yep it should have it. Check the PV Trigger section of the manual. http://www.outbackpower.com/downloads/documents/flexmax_6080/owner_manual.pdf

It's to do with changing albedo (reflectiveness). If you have a surface that is thermally reflective and you replace it with something that's absorbent then you retain more of the incoming heat. It's a big problem with the receding arctic ice cover - reflective snow and ice is being replaced by comparatively absorbent water and rock. PV panels on a steel boat roof are unlikely to make much of a difference and PV panels on dark slate roofs would probably improve things (although the PV panels would likely be grid tied so won't stop generating. Either way it's not worth worrying about because the effect is small compared with the GHG saving of clean electricity generation. As a side note, albedo modification is proposed as a potential measure which could be adopted to reduce the impacts of climate change, even to the extent of choosing lighter coloured crops.

From the OP: "What I would like to achieve is using this excess energy somehow...Anyone know of any simple reasonably priced systems/gadgets or tweaks that can utilise this energy automatically even if to the calorifier, letting it go to waste is really annoying."

I am very interested in this also and I've found two possible approaches: A quick and dirty approach would be to get something like http://www.isocket.eu which would allow you to remotely control your immersion heater (via SMS or Android / iOS app). So on a sunny day you could switch your immersion heater on for a while even if you weren't on the boat. It's not very elegant though. A better looking approach is that a FlexMax has a 12V aux output which could be used to trigger a relay which could switch your immersion heater (or another load) on when the battery reaches a certain voltage.