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Narrowboat Solar Energy Panels - Solar Power Modules - Canal Boat Solar Panels

We believe that Solar panels will contribute significantly to the electrical power needs of our narrowboat. There are a variety of types of Narrowboat Solar Panels on the market.

We know that to charge our batteries, even partly, by using environmentally clean, free renewable energy through the purchase of narrowboat solar energy panels (solar power modules). This can be costly but we understand that in the long run it will save money; although we needed to make an investment of around £1,200 to fit the type of solar panels we wanted. We hope to save considerably on fuel costs, engine and alternator wear and tear as well as extending our battery life.

We are continuous cruisers, running our narrowboat's diesel engine to charge our battery bank. We don't particularly find this to be a hassle ourselves and we have taken steps, by fitting a hospital silencer, to reduce the exhaust noise that may disturb the peace of a quiet popular mooring place. We are also aware that running our engine for four hours or so each day is not a very environmentally responsible way of supplying our electrical energy. Plus we have to consider the wear and tear on the engine and alternators. Our aim is to reduce our engine running time by at least 1 hour per day!

If we leave our boat for periods of time the solar panels will keep our batteries topped up and in good condition while we are away.

As any boat owner will know making large investments in technology and energy is something that needs to be considered carefully. There are, of course, many power solutions on the market and seemingly very little between them to the casual observer.

We already minimise our power use and consumption; this may mean taking steps to be more frugal, switching off unused appliances or moving to more energy efficient choices where available. Switching to Energy Saving Bulbs or LED lights is a great step in this direction and both are available for 12v systems.

There is probably no right or wrong choice when researching renewable energy solutions, so long as you are happy with what you get for your needs, but what you do need to consider is not only cost but how much power you need to maintain charge in your batteries. To understand this you need to consider how much electricity you use and what type of appliances to use.

We recently purchased two SM160M Solara 45Wp 12v solar power panels for our narrowboat from Bright Green Energy, 26 Woodmere Way, Beckenham BR3 6SL.

We liked the look of these flexible panels and know they will realise lower solar efficiency but what we liked was that this flexible type that can be glued or screwed to the curved roof of a boat, or any other surface for that matter and can be walked on.

The Solara brochure says "Tried and tested, this is the most popular marine solar module available. They are made of a high grade stainless steel backing. They are smaller, very thin, slightly flexible and very robust. If fixed to a solid surface they can also be walked on. This is due to the high resistant plastic front foil so there is no glass that can break. The high efficiency solar cells are very productive even under low light levels. For easy wiring all modules have 1.5m pre-mounted cable. As an option the modules edge can be protected with a black UV-resistant edge protector. SOLARA® modules S-Series SOLARA® SM160M - Performance: 180 Wh/d - Nom. Power: 45 Wp - Weight: 3,75 kg ca. Size (lxwxh) mm: 756x460x2 – with cell protector – optional: black UV-resistant edge protector: KS160M - New: Now with more power and a double layer powder coated steel backing plate".

We have included a Victron BS20A Blue Solar 20Amp Solar Regulator, which upon reflection is not aesthetically compatible with the rest of our boat's electricity control panel and would have chosen a different looking controller.

Our narrowboat's solar energy panels have been stuck down with SKLI Solar Panel Adhesive by Sikaflex, a UV safe bonding compound that sets in approx 24 hours and is rock solid. This can also be used to securely 'glue' the feet of the Solar Panel mounting kits to the roof of your Narrowboat without drilling holes or resorting to welding brackets.

How solar panels are connected in narrow boats.

The two solar power modules are connected to our 12volt system in a parallel circuit (Wiring into a 24V system is very different!) We found that to wire the solar panels in parallel you must connect the positive terminal of the first solar panel to the positive terminal of the next solar panel and negative terminal of the first solar panel to the negative terminal of the next solar panel.

It is important to note that when you wire any 12volt equipment in parallel the resulting Voltage and Current is just the opposite effect, voltage wise, of a series circuit. The Voltage in a parallel circuit stays the same and the Current is additive. If each of the boats solar panels in the above example had the potential of producing 350 Amp hours then 350 + 350 = 700 Amp hours, the Voltage would stay the same.

If these devices were batteries then this parallel circuit would yield total voltage of 12 volts @ 700 Amp hours. If these devices were solar modules that produced 17 Volts @ 4.4 amps each then the this parallel circuit would yield 17 Volts @ 8.8 amps.

If in doubt consult a qualified electrical engineer!

We also understand that narrowboat solar panels are probably great for summer but in the depth's of winter will only produce around 10 to 20% of there rated capacity as cloudy, more overcast conditions and less photons arrive on Earth from the Sun. On crisp winter days with clear skys we expect normal outputs, over shorter periods as the sun is lower in the sky and of course there are less daylight hours so we won't get as much charge going back into our battery bank compared to summer.

Bright Green Energy delivered the solar energy modules to us when we were moored on the visitor moorings in Brentford and gave us advice on fixing and fitting.

One of the benefits of Framed Solar Panels rather than the lower efficiency stick on items - is the ability to tilt the panel to face the sun. This is a benefit because Solar Panels produce the most energy when elevated at 30-40 degrees to the horizontal and south facing. There are a range of different Solar Panel mounting kits specialised for Narrowboat and Canal boat Solar Panel mounting.