Friday, April 08, 2016

Electric on the water

Kind of along the lines of Eli’s Lighter-Than-Air musings, I wondered the other day about why tugboats couldn’t be electric. It’s not as if they need to go hundreds of miles. And it turns out the very initial steps are being taken on that, with prototype tugboat hybrids and an electric boat on the Erie Canal.

This isn’t the grand solution to marine traffic, but imagine at each port one set of tugboats took a massive boat 11 miles out, another set took it another 9, and then other boats did the same on the receiving end. That’s four percent fewer emissions from a 1000 mile journey. Not a huge reduction, but might as well take it. It also has some significant environmental justice and urban quality of life benefits by reducing pollution at urban ports where many poor and working-class people live and work.

Some ports have made initial steps to electrify marine transport, requiring cargo boats to turn off their polluting diesel engines when they’re docked, running their onboard machinery through a connection to shore power instead. Some similar steps have also happened at airports where planes are driven to and from gates by efficient land vehicles instead of using aircraft engines. So there’s precedent for piecemeal electrification.

More on the fantasy side, I wonder if there couldn’t be a category of shipping material that absolutely positively does not have to get there overnight, or very fast at all. Maybe drone cargo ships powered by solar, maybe with floating pontoon panels to add some extra oomf, could slowly get the material to wherever it needs to go. Maybe combine that with a SkySail.

9 comments:

Everett F Sargent said...

Having ridden a bunch of 'boats' into and out of ports, I'm pretty sure they all would have thrown me overboard if I had EVER referred to their ship as a boat, just, you know, sayin' ...

Tugs assist in mooring ships at berth, tugs hold ships at berth in adverse conditions (POLB $25K/day like three decades ago even), tugs assist ships in turning in tight navigation channels (except for say the Panama Canal (e. g. Culebra Cut, formerly called Gaillard Cut)), tugs are rarely needed once the ship is in the main inbound/outbound entrance channel. Getting on/off a ship from the harbor pilot boat via the Jacob's Ladder is really rather fun, the bigger the waves the funner it is.

Bollard pull is the standard metric for tugboats (you just might want to look into that one) ...
https://en.wikipedia.org/wiki/Bollard_pull

The necessary calculations are pretty straight forward.

Russell Seitz said...

If you want to start a GreenEx Next Month Delivery line, now's the time to lawyer up-- the Baltic Dry index is so far down that you can charter a Panamax for an eighth the cost of your $25 K a day tugboat, and a megabuck should charter a pair of Panamax for a year.

I had an enjoyable day's run down from Barbados to the Grenadines this winter on a 5,000 ton five master spreading 50,000 square feet , but the rest of the week was spent using the sails for show and stability as we motored, not beat , our way back through the Windwards.( fear of liability means tugs on offer in even armpit of the Caribbean ports)

Plenty of container ships use parasails to save transpacific bunker as they keep to their schedules, but none I know of claim cost savings of as much as !0%

Barton Paul Levenson said...

Paris is pioneering an electric surface-effect craft to provide public transportation up and down the Seine. It apparently splashes less than conventional boats.

Everett F Sargent said...

Fun Fact ...

Electric Boat has been around for over 100 years ...
https://en.wikipedia.org/wiki/General_Dynamics_Electric_Boat

Can you say new-cle-air? I just said a B-A-D word.

https://en.wikipedia.org/wiki/Nuclear-powered_icebreaker
https://en.wikipedia.org/wiki/Nuclear_marine_propulsion
https://en.wikipedia.org/wiki/NS_Savannah

OK, then ... humanity is s-o-o-o-o-o-o-o-o-o-o D-O-O-M-E-D!

Russell Seitz said...

BPL
Please tell us more about the Paris 'electrc surface efect'

MHD ? Electrostatic ?

??

guthrie said...

Surely the obvious thing to do is have the tugboats run by electric from a wire like a train. Thus massively less mass to be moved in the first place, all the tugs need to be is big engine inside a hull.

Barton Paul Levenson said...

I will if I can find the article again... Here we go.

http://www.citylab.com/tech/2016/02/paris-seine-flying-water-seabubble-driverless-alain-thebault-hydroptere/463182/

Russell Seitz said...

Electrique indeed- it's a battery powered water jet hydrofoil.


I remain a great fan of Alain's big boat of the same name-- a seriously extreme seagoing hydrofoil & wingsail trimaran

Fernando Leanme said...

It's better to fuel a tugboat with Compressed Natural Gas, a very clean burning fuel.