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golfCharlie. Thank you for your research. The biggest surprise is that operators can get insurance at all.

Aug 30, 2016 at 5:46 PM | Unregistered CommenterACK

ACK 3:44 Wind turbines do have some protection or shielding for increased resistance, but they can not be made immune, and they are located in areas more liable to be hit. Why are there any trees on any hill or mountain top?

A lightning conductor on top of a church steeple, should allow a strike to "earth" without damaging the building fabric. The electronic timer for the central heating boiler may not work though.

A quick google reveals;

Wind Turbines and Lightning by Nick Gromicko

Wind turbines are tall, isolated towers composed of sensitive electronics, all of which are factors that make lightning a persistent and real threat. A properly installed lightning protection system, however, will intercept the lightning and effectively and safely conduct it to the earth without risking physical destruction to the wind turbine. This issue has become increasingly critical as wind turbine systems become more sophisticated and vulnerable to lightning. Lightning protection systems costs less than 1% of the total capital expenses while improving the cost-effectiveness and reliability of a wind turbine substantially. 

First, a few facts to convey the danger that lightning poses to these power-producing windmills:

According to a German study, lightning strikes accounted for 80% of wind turbine insurance claims.During its first full year of operation, 85% of the down time experienced by one southwestern commercial wind farm was lightning-related. Total lightning-related damage exceeded $250,000.The German electric power company Energieerzeugungswerke Helgoland GmbH shut down and dismantled their Helgoland Island wind power plant after being denied insurance against further lightning losses. They had been in operation three years and suffered more than $540,000 (USD) in lightning-related damage.

Wind Turbine Component Damage
The following systems, arranged in order from most to least vulnerable, may be damaged by lightning strikes:

damage to the control system. These include sensors, actuators, and the motors for steering the equipment into the wind. According to the updated National Fire Protection Association handbook: “While physical blade damage is the most expensive and disruptive damage caused by lightning, by far the most common is damage to the control system”;damage to electronics. Wind turbines are deceptively complex, housing a transformer station, frequency converter, switchgear elements, and other expensive, sensitive equipment in a relatively small space;blade damage. A lightning strike to an unprotected blade will raise its temperature tremendously, perhaps as high as 54,000° F (30,000° C), and result in an explosive expansion of the air within the blade. This expansion can cause delamination, damage to the blade surface, melted glue, and cracking on the leading and trailing edges. Much of the damage may go undetected while significantly shortening the blade’s service life. One study found that wood epoxy blades are more lightning-resistant than GRP/glass epoxy blades;damage to generators; andbatteries can be destroyed, or even detonated, by a lightning strike.

Aug 30, 2016 at 5:32 PM | Unregistered Commentergolf charlie
Aug 30, 2016 at 4:58 PM | Registered Commenterstewgreen

Nick, do you mean "degassing"?

Aug 30, 2016 at 4:43 PM | Unregistered CommenterACK

Golfcharlie - The new BBC Balance™ was in evidene. The interviewer 'challenged' Prof Wadhams over his previous warnings of catastrophe that failed to materialise. But of course he was given ample space to reply unchallenged by the BBC interviewer, or anyone else.
My suggestion to the Professor's idea to starve the planet of life sustaining CO² is that he should lead the way and stop gassing.

Aug 30, 2016 at 4:36 PM | Unregistered CommenterNick

Ross: That is what I got. It must be a standard letter, ignoring any comments on the reason for the resignation.

Aug 30, 2016 at 4:28 PM | Registered CommenterPhillip Bratby

Pcar:

Cetane is only relevant to diesel engines. Technically it is measured in a laboratory diesel engine, although there are shortcut methods that are usually used (distillation and density measurements combined in a formula to produce "cetane index") that are simpler to measure and correlate well with engine performance.

Cetane appears nowhere in the a href="http://www.petrostar.com/assets/downloads/Jet_A.pdf">specification for jet fuel.

Aug 30, 2016 at 4:18 PM | Unregistered CommenterIt doesn't add up...

On resigning from the National Trust I set out in detail my reasons in my resignation letter. All I recieved in response was a standard letter " we are sorry you chose to leave". No explanation or the reasons for their current policy. How arragant.

Aug 30, 2016 at 4:15 PM | Unregistered CommenterRoss Lea

Delay in Flood Resilience Review. Commissioned after large parts of Yorkshire, and the North, were left submerged by filthy floodwater

Poli's writing in Yorkshire Post say 'ooh it's more than a month late' comment
DECC people say "We mean by end of summer"

Aug 30, 2016 at 4:07 PM | Registered Commenterstewgreen

Mike Post:

There is of course a small market for aviation gasoline, for which octane is indeed a key specification. These days 100 Octane fuel is the standard, although some years ago 115 octane was typically supplied for small aircraft. It is a leaded fuel, in part because octane performance otherwise drops sharply at altitude (and the amount of unburnt fuel increases, reducing engine power output). There is intensive research to provide a lead free or lower lead fuel, spearheaded by the FAA.

Jet fuel is another matter altogether: its main specification parameters provide broad control over chemical composition (maximum content of aromatics and napthenes, sulphur and water content, as well as distillation end point, density and viscosity, as well as smoke point - length of a flame when smokiness is observed - which defines burning characteristics), while ensuring a specific energy content, and safety related parameters (freeze point and flash point - temperature at which spontaneous combustion occurs in the presence of a spark). Jet A1 specification

Aug 30, 2016 at 4:04 PM | Unregistered CommenterIt doesn't add up...

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