Guest Post: Shore Power - Ships and Plugs

In our first Guest Post, we welcome Dr Derek McGlashan, a leading voice on

Environment and Sustainability in the UK Ports Industry.

Derek has Chaired a number of national industry groups looking at environment and sustainability, and held a senior position with a UK Major Port. He is an Honorary Research Fellow at The University of Dundee.



In this article, first published on Linkedin in February 2022, Derek presents the view from a port perspective, discussing some of the challenges and concerns associated with this technology.

As many ports launch their own decarbonisation strategies and explore Shore Power as an option, Derek's article raises some interesting points for consideration that aren't always highlighted by proponents of the solution.

This is an interesting debate, and one that will no doubt carry on for some time. Of course, this post has a UK focus, but other regions may have a different perspective. What's your experience of Shore Power in your area? We'd love to hear your thoughts in the comments below.

If you'd like to engage on this with Derek, you can connect with him to start a conversation in The Smart Ports Alliance app (available from the App Store and Google Play store)


On the face of it, plugging ships that call at ports into the electricity network looks like a clear winner for decarbonisation and emissions reductions. This has been the start place for many a discussion over the years. There has been shore power in some UK ports for many years at a small scale for workboats, tugs and pilot vessels. Not so much for larger vessels. Why is that?

Electricity Infrastructure

Electricity is expensive in the UK (and currently becoming more-so), electrical infrastructure is expensive to purchase, install and maintain. But those costs pail into insignificance if there is not the capacity available in the port’s connection agreement, greater capacity has to be purchased and this carries a cost.

Under the UK Government’s recent changes (the TCR for example) those costs for transmission charges are now based on your maximum capacity, a change from the current ‘triad’ approach, where the charge is based on usage in three peak 30 minute periods.

If the physical infrastructure is not capable of supplying the maximum demand of electricity needed, then that infrastructure needs to be upgraded as well – this bill could be many, many millions of pounds, depending on how much of an upgrade is needed. I have heard of cases where the upgrade would need to extend beyond the Distributor into the National Transmission Network – then the costs really rise… It could also t