Fitting solar panels or a wind turbine to a narrowboat

Running a diesel engine to charge your batteries is a hassle. Not only that, but it disturbs the peace of a quiet mooring, and isn't a very enviromentally responsible way of getting energy. It isn't even very good for the engine: most alternators only give a light load to a big propulsion engine, which is designed to be run under much heavier loads. That is why many people leave boats in gear while charging: but that, of course, burns more diesel, and is even less environmentally friendly!

An alternative is to charge your batteries using clean, free renewable energy. You should find in the long run it will even save you money: although you need to make an investment to fit solar panels, you will save considerably on fuel costs, engine wear and tear and battery replacement.

Solar panels can contribute significantly to the electricity needs of a narrowboat. There are a variety of types of solar panel on the market.

The first generation of solar panels were framed modules based on a number of crsytalline silicon solar cells, and many of the most efficient panels available today are of this type. Framed panels will work well on a narrowboat roof, and you will see many narrowboats with this panels of this type. We sell a range of crystalline panels from BP Solar.

However, the latest panels based on amorphous silicon technology are very thin, tough and flexible, and give a very low profile when glued to the roof of a boat. You may need a slightly larger area than with the old style framed panels, but once they are in place you will barely know they are there!

We recommend the UniSolar adhesive backed panels as the most appropriate solution, as they can be stuck down to the curve of the roof. They can even be walked on with soft soled shoes.

In summer one 68 Watt panel should supply all the electricity you need for lighting and water pumps. Use energy efficient bulbs if possible. The newer LED bulbs are very efficient, and can often be installed in existing fittings. Fluorescent lights are also efficient relative to conventional bulbs. If you run a fridge you should consider fitting two panels, as fridges are rather power hungry compared to other appliances.

If you leave your boat for long periods of time and just want a solar panel to keep your batteries in good condition while you are away, you can get away with a smaller panel. The Spectra range of small panels are very suitable for keeping batteries topped up, and come in 5, 10 and 20 Watt sizes. They are semi-flexible, and will gently bend to fit to most narrowboat roofs (provided the radius is not too tight). They can be mounted either using the 4 grommet holes in the panel corners, or by gluing the panels down.

The small Spectra panels do not need a solar controller if the capacity of the battery bank is small relative to the size of the panel. However, for larger panels such as the UniSolar models we would always recommend the use of an appropriately rated solar controller.

Solar panels are great for summer - but alas, in the depths of a British winter, even a large array may not provide all the power you need. A small wind turbine such as one of the Rutland models can be a more cost effective power solution in winter. A lot depends on the location of your mooring - a wind sweeping across an exposed fen will generate considerably more electricity for you than you will get in a city centre marina, surrounded by tall apartment blocks.