The Anonymous Widower

CIP Picks Stiesdal Floater For 100MW Scottish Offshore Wind Farm

The title of this post, is the same as that of this article on Offshore Engineering.

These two paragraphs introduce the project.

Copenhagen Infrastructure Partners (CIP) has selected Stiesdal Offshore’s TetraSub floating foundation structure for the 100MW Pentland Floating Offshore Wind Farm project, to be located off the coast of Dounreay, Caithness, Scotland.

The technology has been said to offer a lightweight and cost-effective floating solution, based on factory-made modules which are then assembled domestically in port to form a complete foundation.


  1. The TetraSub seems to have been designed for ease of manufacture.
  2. One if the aims appears to be to build a strong local supply chain.
  3. The TetraSub was designed with the help of Edinburgh University.
  4. The TetraSpar Demonstrator is in operation off the coast of Norway.
  5. This page on Mission Innovation describes the TetraSpar in detail.
  6. The TetraSpar foundation, owned by Shell, TEPCO RP, RWE, and Stiesdal.
  7. It can be deployed in water with a depth of up to 200 metres.
  8. Currently, they carry a 3.6 MW turbine.
  9. At that size, they’d need 27 or 28 turbines to create a 100 MW wind farm.

The home page of the Pentland Offshore Wind Farm gives more details.

This article on is entitled CIP And Hexicon To Halve Pentland Floating Wind Project Area.

  • The project area has been halved.
  • The number of turbines has been reduced from ten to seven.
  • Compact turbines will be used.
  • The project will be built in two phases, one turbine in 2025 and six in 2026.
  • Effectively, the first turbine will help to fund the second phase, which eases cash flow.

The changes show how the wind farm has changed during development due to local pressures and improved technology.


It does seem that the competition is growing in the field of floating wind turbines.

Given the quality of the research and backing for these floats and the fact they now have an order, I wouldn’t be surprised to see this technology be a success.

October 13, 2022 Posted by | Energy | , , , , , , , , | 2 Comments

One Of The Three Best Pastas That I’ve Ever Eaten!

I like pasta and regularly cook myself a quick pasta dish, like this one in Serial Cooking – Pasta With Yogurt Sauce For One.

I was staying in the Premier Inn by Chester railway station last night, so I popped in to the Modern Italian Restaurant next door called The Yard.

It was one of the three best pasta dishes, that I’d ever eaten and the others had been in Michelin-starred restaurants in Italy.

The chef had one pasta dish on the main menu, but it wasn’t gluten-free.

So he happily modified it for me.

October 13, 2022 Posted by | Food | , , | Leave a comment

Battery Use In Class 777 Trains

In the November 2022 Edition of Today’s Railways, there is an article about Merseyrail’s new Class 777 trains.

This extract describes the use of batteries on the trains.

All units have small batteries for moving independently around depots. Seven units are now being fitted with larger 160 kWh Lithium Titanate Oxide (LTO) batteries and associated traction converter in the leading coaches in space that could also be taken up by a transformer and AC equipment if some units were converted to dual /Battery operation (there would not be the space for tri-mode AC/DC/Battery operation). The cooling system for the battery lies has been roof-mounted. The battery boxes have been supplied by ABB and the batteries themselves by Toshiba. 777002 has been converted as a trial to prove the concept in 2021 but has now been converted back to an EMU.

Stadler explained that the battery life would normally be 8-10years but if the units are only used in battery mode for the 2 km between Kirkby and Headbolt Lane then that is expected to be more like 15 years. However the batteries have the potential to do around 40 miles, so Bidston-Wrexham is possible, with a 15 minute recharge time required at Wrexham before returning. Maximum speed in battery mode is 60 mph compared to 75mph as a DC EMU.

This is a map of how the network might look.

These are the lengths of routes, where the Class 777 trains might run on batteries.

  • Bidston and Wrexham Central – 27.5 miles – Possible with a charge at Wrexham Central.
  • Canada Dock Branch – 4.7 miles – Dual-voltage trains.
  • Chester and Crewe – 21.2 miles – Possible with a charge at Crewe
  • Chester and Runcorn East  – 13.1 miles – Possible without recharging
  • Ellesmere Port and Runcorn East  – 10.8 miles – Possible without recharging
  • Hunts Cross and Manchester Oxford Road – 27.1 miles – Possible with a charge at Manchester Oxford Road
  • Kirkby and Wigan Wallgate – 12.1 miles – Possible without recharging
  • Ormskirk and Preston – 15.4 miles – Possible without recharging


  1. There are a lot of possibilities to use Class 777 trains with batteries.
  2. Charging might be needed at only three stations; Crewe, Manchester Oxford Road and Wrexham Central.
  3. Four route extensions are possible without charging.

Merseyrail are going to have plenty of uses for the sixty trains, that they have on option.

Train Efficiency On Battery Power

In an article in the October 2017 Edition of Modern Railways, which is entitled Celling England By The Pound, Ian Walmsley says this in relation to trains running on the Uckfield Branch, which is not very challenging.

A modern EMU needs between 3 and 5 kWh per vehicle mile for this sort of service.


  • The Class 777 train is a four-car train, but is only five metres longer than a three-car train.
  • So applying Ian’s formula, it seems that to do forty miles, the battery will be between 480 and 800 kWh.
  • If it is mathematically like a three car train, it seems that to do forty miles, the battery will be between 360 and 450 kWh.

A 160 kWh battery is obviously too small.

But the extract says that the batteries are fitted in the leading coaches, so can we assume that each battery train has two leading coaches and two batteries.

Does the battery train have a battery capacity of 320 kWh?

  • Assuming it does, it would appear that after using Ian’s formula for a four-car train gives a figure of 2 kWh per vehicle mile.
  • A three-car train gives a figure of 2.67 kWh per vehicle mile.

I suspect that these low figures are down to good engineering and a very efficient electrical system on the train.

But then I did write Stadler FLIRT Akku Battery Train Demonstrates 185km Range.


These trains are going to set new standards for a city metro.

October 13, 2022 Posted by | Transport/Travel | , , , | 5 Comments