Fitting solar panels 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 environmentally responsible way of obtaining 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's 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. Although you need to make an investment to fit solar panels, in the long run, you should find this will even save you money: 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 several different types of solar panel on the market. Both traditional crystalline types, and the more modern amorphous types, work well on narrowboats.

We recommend the UniSolar adhesive backed panels as the most appropriate solution for a narrowboat, because 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. Make sure you use energy efficient lighting where possible, with LED or fluorescent units to give the maximum light for the minimum power. If you run a fridge, you should consider fitting two panels, since 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. They come in 5, 10 and 20 Watt sizes, are semi-flexible, and will gently bend to fit the curve of most narrowboat roofs provided the curve 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 GB-SOL panels listed on that page are also a good option if you'd like a bit more power.

Framed solar panels are the best value in terms of the power output for a given price. We have a great range, from well-established manufacturers such as Kyocera and BP Solar, as well as lower-priced models which we import directly.

If the capacity of the battery bank is small relative to the size of the panel, the small Spectra panels do not need a solar controller. However, for larger panels such as the UniSolar models we would always recommend the use of an appropriately rated solar controller. You might like to also consider a sophisticated MPPT regulator, which delivers more power to your battery than a conventional regulator.

• Work out my power use
• Buy a framed solar panel
• Buy a peel-and-stick solar panel