These days it’s all offshore this, offshore that in the renewables game. But how about the really offshore – boats?

It’s not like shipping is exempt from examining where carbon and cost savings can be made – and with aesthetic objections sometimes made to fixed renewable installations, it stands to reason that less are going to get hot and bothered about renewables knocking around the ocean waves.

The possibility of ‘solar shipping’ recently came to the attention of the BBC, so it’s safe to say that the move from quirky to common is already apace. Their piece looks at the technology of an Australian firm with the does-what-it-says-on-the-tin name Solar Sailor, specifically a boat in Hong Kong that transports golfers to an island course.

Using technology similar to hybrid cars, roof-bound solar panels provide the drive for docking manoeuvres, while diesel does the harder driving when out on the water. One of the boat fleet even has a panel-covered sail for even more Wattage, with the power of the wind thrown in. Old-school meets new-school. 

Ferrying golfers is all well and good, but clearly the bigger sustainable inroads can be made in the larger-scale world of cargo shipping. Around 50,000 ships carry 90 per cent of world cargo, and these ships tend to use a carbon-heavy oil known as bunker fuel. So can solar play a role here? Well, yes.

The BBC’s article quotes the company’s founder Robert Dean extensively, who’s enthusiastic about a trial of a 130-foot sail on the carrier ship of a mining company shipping to China. With a sail of this size, it’s clear that harnessing the wind is going to be the bigger boon. The article says:

By harnessing the wind, the company estimates that the giant sail could shave 20% to 40%, or around A$3m (£2m; $3.1m), off a ship’s annual fuel bill when travelling at 16 knots (18mph), with the solar panels contributing an extra 3% to 6% saving.

Other solar-sailing companies are available, mind. It’s fair to say there’s a few patents pending in this emerging field, like the multi-sailed approach of Eco Marine Power. Let’s just hope that the solar-sail arms race is not such that they get so large they’re shading each other.

For the shipping industry, the energy used getting monster boats about is only half the problem – they also burn a lot of fuel while docked, doing their loading and unloading. Forward-thinking carrier ships are taking to solar, like the M/V Auriga Leader that the LA Times were impressed by when it docked at Long Beach.

The giant ship gets 10 per cent of its energy needs from 300-plus PV panels – and the shipping company behind the plan are hoping that they’ll stand up to the hard life of the seafarer, eventually providing full docking power needs.

It may seem an odd parallel, but the drivers for change here aren’t too dissimilar to those that could precipitate an electric car roll-out in businesses – something we covered in our recent Plugged-in Fleets report. Effectively, it’s all about looking at the lifetime costs of making a change against what you’ve already got. The big shots of shipping may soon be crunching the same sort of calculations as the owners of fleets of cars and vans – and concluding that innovation towards sustainability can’t sail in soon enough.