Published Resources

During his GL Noble Denton days allatsea often found himself witnessing tug’s bollard pull trials and upon a successful conclusion, issuing a GLND ‘Bollard Pull’ certificate. This was interesting and usually, due to the locations invariably being in the Meddy, very lovely work. There was one concern however. GLND did not have their own published guidelines or procedures with respect to how these trials should be conducted. What became the norm was to apply a bit of sailors common sense, pinch a bit of the Classification societies’ methodology and be guided in the main by the brief but excellent ‘Bollard Pull Code’ issued by Steerprop Inc.

A link to that splendid publication can be found immediately below this paragraph.

Steerprop bollard pull code

Ever wondered why energy companies would want to build an offshore windfarm? It’s a tough old game, no joke. Many prime contractors, especially cable installation firms, have gone the way of bankruptcy. Shallow water, fast currents, drying heights, daft interference  by government departments that should know better, large engineering challenges, a very small skill pool  and a burgeoning growth of, in the main,  mal-educated HSE advisors, all make for a giant head-ache from beginning to end.

As a ball park figure example, a 3.0 MW WTG installed ashore and plumbed into the the national grid is around 20%  of the cost of its offshore equivalent.  Leaving aside the fact that offshore windfarms benefit from more efficient wind yields than their onshore cousins (but not by a huge margin), the main reasons for the relatively  small number of WTGs actually onshore in our small but windy island is because planning permission is so difficult to get. Usually due to the landynimbyfolk kicking off an uproar every time an onshore project is proposed.

To encourage the energy firms to build the more ‘challenging’ and expensive renewables generators (of all types), a device had to be invented that would encourage the energy firms to invest the large amounts of wonga  required.  The result was the ROC.

The Renewables Obligation Certificate is the devilishly clever way the the then Labour Administration achieved it. Clever, but brutal to the end user, that’s you and me folks.

Please see the document in the link below to reveal all. Note that ROC‘s are traded amongst the energy firms in their own market place. They often change hands at huge premiums to ‘face’ value.



Ask any lifting wallah what the best shackle is and he’ll likely tell you ‘Crosby‘. I’d agree with them. See the link below for the reason why.

Crosby Shackles

Wire Sag

You’re driving your tug, you’re got 800 metres of 90mm towline out and the load on the line is 160 tonnes. What’s the depth to which the wire will sag (the catenary) beneath the sea surface? Will it foul the seabed?

The following handy spreadsheet will tell you. No frills, no fanciness, just practical Danish usefulness.

Wire Catenary Calculator

Spell checking reports.

The poem below is a reminder that just because a machine tells you all is well, it’s usually best to cast an eye over  to check too. This includes running a spell-check on a report or document.

Eye halve a spelling chequer
It came with my pea sea
It plainly marques four my revue
Miss steak’s eye kin knot sea.

Eye strike a key and type a word
And weight four it two say
Weather eye am wrong oar write
It shows me straight a weigh.
As soon as a mist ache is maid
It nose bee fore two long
And eye can put the error rite
Its rare lea ever wrong.

Eye have run this poem threw it
I am shore your pleased two no
Its letter perfect awl the weigh
My chequer tolled me sew.

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