Welcome back to Canal Boat UK! In our ongoing quest to bring you the best narrow and canal boat information, today we are publishing a guide on narrowboat solar systems. This article aims to be both informative and a place where you can read reviews of the different components you will need for a full narrowboat solar system.
Why Would you Need Solar Panels on your Narrowboat?
Solar panels are a great way to source electricity for your narrowboat in an environmentally friendly way. Most of the electricity generated in the UK is still coming from power stations that burn fossil fuels, which we all know are not environmentally friendly in the slightest. Until the UK manages to generate a sizeable amount of its electricity with renewable sources solar panels are pretty much the only way to help the environment whilst consuming electricity.
It’s also a matter of convenience, especially when you are continuously cruising the canal network. It can be annoying to have to run your boat’s engine or visit a marina to charge up your leisure batteries. Having solar panels will relive the need for this, and in some cases make a canal boat self sufficient as far as electricity goes.
Won’t They Look Ugly?
Thankfully, solar panels have been around for a while now and the technology is developing nicely. In the beginning you may have ended up with a boat that looks like this…..
The solar panels were thick and unwieldy, and if they weren’t directed towards direct sunlight would drop off in performance massively. Although we are still not totally away from this, you can afford to fit solar panels that fit more in with the natural aesthetic of your narrowboat without a massive drop off in the electrical charge they are giving you. You can have a boat that looks more like this…..
I bet you struggled to even find the solar panels in that last picture, they are so well inset into the roof of the boat! This makes fitting solar panels a much better option, and you don’t have to ruin your boat’s look to have them!
And things will continue to improve as the years go on. I bet we are not too far away from solar panels that can give equal charge on a cloudy day or in the winter, its just a matter of time in my opinion. And they will continue getting a lot smaller too.
What Do I Need for a Full Narrowboat Solar System?
A narrowboat solar system is actually quite simple. Of course you need the solar panels 🙂 But you also need a charge controller to help regulate the power the panels are giving to your leisure batteries. You don’t won’t batteries that are getting over or under charged without your knowledge 🙂
Are There Different Types of Solar Panels for a Narrowboat?
At the time of writing, these are the main types of solar panels you should look out for….
Flexible or Rigid
The traditional type of solar panel that everyone has seen a million times is the rigid style. These are framed thicker solar panels such as the one below. Throughout this article, simply click the product images to go and view the product for yourself over at Amazon.
One of the biggest advances in solar panels in recent years has been the introduction of the flexible solar panel. These have been excellent for boat owners as they are much easier to fit, laying flat on your boat’s roof. Most can also be walked on, which is especially handy if you are a solo boater that needs to get up on the roof a lot in locks!
Polycrystalline vs Monocrystalline solar panels
These are the top two solar panel types on the market right now. Both offer a good level of solar energy efficiency compared to older panels. Monocrystalline panels are the absolute apex though, offering a top of the line efficiency along with an excellent product lifespan. If you want the ultimate in solar panel production with the smallest possible size, these are the ones to get.
Polycrystalline panels (with their distinctive blue colourisation) are still a good option, and are slightly cheaper. As well as having a slightly worse efficiency rate, these panels can be effected by high temperatures (not much of a problem in the UK though) and have more of a question mark over durability/lifespan.
The Solar Charge Controller
On top of choosing the right type of solar panel for your needs, you also need to make sure that you buy the right type of charge controller for your needs. If you want to charge both the starter battery and your bank of leisure batteries, you will need a dual battery solar charge controller. If you have low powered solar panels, you would generally be fine with a cheaper PWM (pulse width modulation) controller. These just match the output of the solar panels to that of the batteries you are trying to charge, to make sure they will accept the electrical charge.
When you start using more high powered solar panel arrangements, you will need a MPPT (maximum power point tracking) charge controller. It will take the power from your solar panels and optimise it even further, taking into account things such as the level of charge in your batteries and giving them the optimal power for that battery state. Most boaters with solar panels seem to be going for the MPPT charge controller no matter what these days, especially as they can help you get the best solar charge from your panels even through winter!
Solar Panel Arrays and Arrangements
An array is simply a grouping of solar panels together. A lot of people opt for a single array of solar panels, but as solar becomes a bigger part of narrow boat life I think we will start seeing more complex arrangements.
Parallel VS Series
Running an array of solar panels in a series basically means you string them together in one daisy chained setup. This will give you the maximum power output, but means that one weak link can effect the whole chain. For example, if one of the solar panels is shaded or broken (meaning it isn’t at maximum output), this will affect the output you get from the whole chain array.
For this very reason, most people with multiple solar panels usually opt for creating an array in parallel. This will give you the best output from those panels. It won’t matter if one of them is shaded or broken, as it will only affect the output from that panel. You are basically wiring each panel up to your circuit individually rather than daisy chaining them into one longer circuit.
Make sure to check the total amps that your solar panel or panels output, and make sure that the charge controller is rated to at least match this figure. If the amp of your panels is higher than that of the controller, it will limit your output to the amp rating of that controller.
How Many Arrays ?
Most people seem to start by putting one array on their narrow boat, but I think as our reliance on solar becomes more we will start seeing people adding multiple arrays.
The thing is, if you have different types of solar panels, they would work more efficiently if they were put into their own arrays. Mixing and matching panel brands and types into one array isn’t usually the best option.
When you do this, it also means you can choose whether you want each array to be a parallel or series array. Some charge controllers allow you to program in multiple arrays (as long as it can handle the total current flowing in from these arrays), or you could simply buy a charge controller for each array.
How Much Power Do I Need from my Narrowboat’s Solar Panels?
If you are happy with a light charge to simply top up or support the charge of your batteries, rather than be the main source of charge, a 100 watt system would do the trick. Some people even install 50 watt systems to keep their batteries ‘alive’ when away from the boat for long periods.
For the average boater that wants to rely more heavily on their solar system, 200-300W is about the range to go for.
For someone with a particularly large or power hungry boat, it then becomes a case of how many solar panels will fit on my roof 🙂 Something that is getting easier as solar panels become ever more efficient.
Following on from these general recommendations, I want to show you a way to calculate your usage a bit more accurately. You can go over to the Rapid Tables website, who have an awesome energy usage calculator. Simply enter in the different appliances that you have on board one by one, add in the number of hours the appliance is used every day and the calculator will spit out a daily, monthly and yearly energy consumption figure in KWH. This is designed for mains appliances, so might not be totally accurate when using 12 volts, but it is better than blindly guessing 🙂
Lets run a few typical examples through that most boaters have.
We all want to keep our food cold right 🙂
THE ELECTRIC KETTLE
If you are anything like me, you will love drinking tea and coffee. An electric kettle is a must then!
Lets round this off with probably the most popular appliance, the TV. Love watching EastEnders or morning TV? This one is for you 🙂
Firstly, did you realise your fridge uses around four times more electricity than your TV and kettle combined? Crazy right! I would recommend everybody does this, even if it is just to give you an insight into your energy usage.
These three appliances are using 6.01 KWH a day. To work out the solar panels that we need to offer the desired power, you can head over to Leading Edge and their solar panel size calculator. Just be aware that the first calculator gives a result in KWH (kilowatt hours), whereas the solar panel size calculator asks for WH (watthours). Make sure to do the relevant conversion in between.
For those 3 appliances and a 6.01KWH daily consumption, this is what the calculator came up with.
I like the detail that this calculator goes into, allowing you to get the appropriate wattage for each different style of solar panel. You can see that if I go for a flat type, I would need 400w in the winter just to run those appliances.
Of course, this calculator is assuming that solar power is your only source of power and what you are 100% using to run the appliances with no additional help.
How Can I Get the Most out of my Narrowboat’s Solar Panels?
Keep it Clean
Any debris or excessive dust and muck on your solar panels will mean they are not running fully efficiently. Solar panels are getting better at dealing with dirt, but it is still important to regularly wipe them off carefully to get the best charging results.
All in all, solar panels don’t need a lot of maintenance apart from cleaning them. Just check how much charge they are giving you from time to time to make sure you are getting the amount of electricity generation you expect. Sudden drop offs suggest a problem with a solar panel or the system around it.
Keep it 12 Baby!
The main thing to consider is to try to run as much of your boats electrics from the same 12 volt power that comes from your boats leisure batteries. A lot of boats have invertors that will convert this 12 volts into a much more convenient 240 volts. This means that you can plug normal mains appliances you would use in a land-based home on a boat!
However, this convenience comes at a cost. When converting from 12 to 240 volts you would be surprised how much of that electric is either used or lost in the process. Enough to make your narrowboat not as energy efficient as you think. This is fine if you are always plugged into a shoreline, but I would assume that anyone thinking of installing solar panels has plans to cruise for extended periods. In this situation, you want to use your solar power as efficiently as possible.
Yes, 12 volt appliances are often more expensive and inferior to mains appliances, but buying them is a sacrifice. One that becomes totally worth it when you are out on the cut and not worrying as much about power drain. Get creative and do as much as you can in 12 volt! Trust me, you will thank me later.
If you can’t stand 12 volt appliances, at least make sure your fridge is 12 volt! Fridges are often one of the biggest culprits on battery drain, as they are fairly sizeable appliances that are left on continuously!
This seems to be fairly common knowledge amongst boaters these days, but I want to mention it all the same. LED lights consume way less electricity than regular bulbs, and any lighting on your boat should be switched over for maximum efficiency!
Avoid Heating Elements
Anything with a heating element will use a crazy amount of electric (look at the electric kettle above!), therefore if you can do without these items you will be saving yourself a lot of energy drain. Maybe boil that water on a stove top kettle 🙂
Make Sure You Have an Appropriate Size Battery Bank
This is the step a lot of people forget about, making sure that they have the appropriate sized battery bank for the power consumption they have on their boat. I have seen people complaining of energy problems and then found out they have a stupidly small battery bank. On the other hand, you don’t want to waste money on a massive battery bank that never gets used.
Thankfully, Leading Edge have another calculator, this time the battery bank size calculator 🙂 Simply enter in the energy consumption figures you worked out above and it will spit out the appropriate battery bank size. For my 6.01KWH a day it told me I needed just over 2000ah for a 2 day battery reserve to keep those 3 appliances detailed above running 🙂
This calculator even lets you state the lowest level of charge you want your batteries to go to. Make sure to check out the battery type you are using and the minimum recommended charge levels and include in the calculation.
Now lets get into the nitty gritty and tell you about some of our recommended solar panels and controllers.
Which Solar Panels are Best for a Narrowboat?
Well, that depends on how much you want to spend and the amount of ‘juice’ you want from your solar panels. For example, you can buy one of the newfangled panels that are smaller and thinner. To get the same output from an older panel would require something bigger. If you have plenty of space on your narrowboats roof and don’t mind something bigger and bulkier, you could get better value by going for these slightly older tech panels. If space is limited on your narrowboats roof, you may have to invest a bit more in newer tech panels to get a result you are pleased with.
Before choosing any solar panel, map out how much space you have on your narrowboats roof and what mounting style you will need to go for. Rigid panels on raised mounts can clear mushroom vents, for example, but may get more in the way when someone is trying to move along the roof. Get exact dimensions of any panels you are interested in and plan out in detail how you will place on your boat’s roof!
Best Rigid Solar Panel for a Narrowboat
A lot of people seem to be going with Victron for their panels, and yes they do have quality panels but you will pay a premium for them. At the time of writing, I am loving the Renogy brand of panels. They are making quality panels, even as far down as the quality of the diode boxes on the back, for a more competitive price. They seem a great balance between the over priced Victron and the unknown quantity of generic Chinese brands. Renogy is ,after all, a quality company based out of the US of A 🙂
This Renogy 160W Monocrystalline panel offers a great amount of power in the most compact design for a rigid panel. And at a price that would only get you a more basic panel with Victron. If its a rigid panel you are after, you can’t go far wrong here.
Renogy also have a very tempting double pack of 100w monocrystalline panels at an even better price. Not quite as space efficient though.
To be honest, with these prices on offer for Renogy Monocrystalline panels, I wouldn’t even bother with Polycrystalline 🙂 If you are really on a budget though, here is a solid option from Eco-Worthy.
Best Flexible Solar Panel for a Narrowboat
Continuing on with the Renogy theme, they also have a great lineup of flexible monocrystalline panels, at a much more competitive price than some of their more when known rivals. They come in two flavours, the 100w panel below…
Or the 160w variation….
If you want an elegant look to your boat, even with solar panels mounted, these are the ultimate in slim and unobtrusive design.
And I know what some of you are thinking right now! Why are you recommending these cheap and nasty panels, when we could be getting prime Victron (or some other household name brand) panel. The thing is, these aren’t cheap and cheerful in the slightest. They are a well respected option in America already! Read some Amazon reviews below to see I am not the only one recommending them 🙂
Which Charge Controllers are Best for a Narrowboat?
I will not go into the exact specifications that you need, such as the amp needed for your particular array of solar panels. It is up to you to get that right. Here I will just highlight a couple of models of solar charge controllers that I think would be best for your narrowboat.
If you have a pretty low powered set of solar panels or don’t rely on solar too heavily, you could probably make do with a PWM charge controller, although I would at least go for one that is more intelligent. This one from EPEver offers an excellent set of features for a decent price. Yes, it will help you get more out of your solar panels, but is still not as optimisable as the more advanced MPPT controllers.
However, if you want the ultimate solar setup for your narrowboat and the peace of mind that you are squeezing the very last drop out of your expensive panels, you should go for a MPPT charge controller. My personal favourite right now is another one from EPEver, who really seem to be knocking it out of the park with affordable charge controllers, this time an MPPT one.
So, there you have it, my full set of advice and recommended products for anyone looking to add solar panels to their narrow or canal boat 🙂 I hope that you now have a better idea and starting point for your solar journey! If you have your own experience with narrowboat solar systems, we would love to hear all about it in the comments section below. I am not exactly an expert, just someone who loves narrowboats!!