WIND TURBINES USE ELECTRICITY FROM GRID
ELECTRICITY FROM THE GRID IS NOT ACCOUNTED FOR IN THEIR OUTPUT FIGURES
Coal, gas, thermal, hydro and nuclear power stations have a life span of 45+ years that can be easily extended if maintained properly. Solar and wind turbines have a life span of 10 to 20 years. Any cost analysis would quickly determine that renewables minus subsidies are much more expensive.
The facts about wind turbines are as follows:-
Wind turbines are using electricity from the grid which is not accounted for in their output figures. Other electricity generating plants (coal, gas, thermal, hydro, nuclear) use their own electricity and the difference
between the amount they generate and the amount delivered to the grid is readily determined.
Wind turbines operate with wind at speeds of approx. 15kmh to 80kmh after which they shut down. When the wind is not blowing or the wind is blowing too hard the wind turbines are shut down & they take power from the electricity grid to keep the main shafts turning slowly to prevent damage.
Where wind turbines have been installed in cold locations the power from the grid is used to keep the blades rotating slowly to prevent icing and to power their hydraulic systems to keep the blades facing in the same direction.
Wind turbines also require power for following:-
1. Yaw mechanism to keep the blade assembly perpendicular to the wind
2. Turbine blade-pitch control to keep the rotors spinning at a regular rate
3. Lights, controllers, communication, sensors, metering, data collection, etc.
4. Heating the blades – this may require 10%-20% of the turbine’s nominal (rated) power heating and dehumidifying the nacelle
5. De-humidification of the nacelle must be expected during periods with increased humidity, low temperatures and low wind speeds
6. Oil heater, pump, cooler, and filtering system in gearbox hydraulic brake to lock the blades in very high wind.
7. Thyristors to graduate the connection and disconnection between generator and grid.
8. Magnetizing the stator — the induction generators used in most large grid-connected turbines require a “large” amount of continuous electricity from the grid to actively power the magnetic coils around the asynchronous “cage rotor” that encloses the generator shaft; at the rated wind speeds, it helps keep the rotor speed constant, and as the wind starts blowing it helps start the rotor turning (see next item); in the rated wind speeds, the stator may use power equal to 10% of the turbine’s rated capacity, in slower winds possibly much more
9. Using the generator as a motor (to help the blades start to turn when the wind speed is low or, as many suspect, to maintain the illusion that the facility is producing electricity when it is not,‡ particularly during important site tours or noise testing (keeping the blades feathered, ie, quiet)) — it seems possible that the grid-magnetized stator must work to help keep the 40-ton blade assembly spinning, along with the gears that increase the blade rpm some 50 times for the generator, not just at cut-in (or for show in even less wind) but at least some of the way up towards the full rated wind speed; it may also be spinning the blades and rotor shaft to prevent warping when there is no wind.
“Could it be that at times each turbine consumes more than 50% of its rated capacity in its own operation?! If so, the plant as a whole — which may produce only 25% of its rated capacity annually — would be using (for free!) twice as much electricity as it produces and sells. An unlikely situation perhaps, but the industry doesn’t publicize any data that proves otherwise; incoming power is apparently not normally recorded”.
Is there some vast conspiracy spanning the worldwide industry from manufacturers and developers to utilities and operators? There doesn’t have to be, if engineers all share an assumption that wind turbines don’t use a significant amount of power compared to their output and thus it is not worth noting, much less metering. Such an assumption could be based on the experience decades ago with small DC-generating turbines, simply carried over to AC generators that continue to metastasize. However errant such an assumption might now be, it stands as long as no one questions it. No conspiracy is necessary — self-serving laziness is enough.
Whatever the actual amount of consumption, it could seriously diminish any claim of providing a significant amount of energy. Instead, it looks like industrial wind power could turn out to be a laundering scheme: “Dirty” energy goes in, “clean” energy comes out. That would explain why developers demand legislation to create a market for “green credits” — tokens of “clean” energy like the indulgences sold by the medieval church.
An observer in Toronto, Ontario, points out that the blades of the turbines installed at the Pickering nuclear plant and Exhibition Place turn 90% of the time, even when there is barely a breeze and when the blades are not properly pitched — in a region acknowledged to have low wind resource.
In large rotating power trains such as this, if allowed to stand motionless for any period of time, the unit will experience “bowing” of shafts and rotors under the tremendous weight. Therefore, frequent rotating of the unit is necessary to prevent this. As an example, even in port Navy ships keep their propeller shafts and turbine power trains slowly rotating. It is referred to as “jacking the shaft” to prevent any tendency to bow. Any bowing would throw the whole train out of balance with potentially very serious damage when bringing the power train back on line.
‘In addition to just protecting the gear box and generator shafts and bearings, the blades on a large wind turbine would offer a special challenge with respect to preventing warping and bowing when not in use. For example, on a sunny, windless day, idle wind turbine blades would experience uneven heating from the sun, something that would certainly cause bowing and warping. The only way to prevent this would be to keep the blades moving to even out the sun exposure to all parts of the blade.
So, the point that major amounts of incoming electrical power is used to turn the power train and blades when the wind is not blowing is very accurate, and it is not something the operators of large wind turbines can avoid.
There is likely need for a hefty, forced-feed lubricating system for the shaft and turbine blade assembly bearings. This would be a major hotel load. I can’t imagine passive lubrication (as for the wheel bearings on your car) for an application like this. Maybe so, but I would be very surprised. Assuming they have to have a forced-feed lubrication system, given the weight on those bearings (40 tons on the bearing for the rotor and blades alone) a very robust (energy-sucking) lubricating oil system would be required. It would also have to include cooling for the oil and an energy-sucking lube oil purification system too.’
–Lawrence E. Miller, Gerrardstown, WV, an engineer with over 40 years of professional experience with large power train machinery associated with Navy ships.
By Eric Rosenbloom
A Problem With Wind Power
[www.aweo.org] [click here for printer-friendly PDF]
The emissions generated in Mining for the various components, the Manufacture (They are nearly all made in China these days using Coal Fired Power Stations and it is they and not us that are adding to the world’s emissions because we are ONLY supplying the coal!), Transport (including the significant CO2 emissions from the Shipping), Installation, Maintenance and cable network..
We could dismantle the IPCC overnight and put aside all these foolish man made global warming fears forever by employing nuclear energy. Currently, there are 440 nuclear reactors in operation in some 30 countries around the world. The number of countries with operable nuclear reactors is increasing, The Netherlands have now opted for them. The United Kingdom, has 15 nuclear power reactors in operation as of this time.
One of the largest plants is situated in France, where about 70 percent of total electricity generation was derived from nuclear sources in 2018. It would be possible to meet the demand of an increasingly energy-thirsty world and a burgeoning world population – at a reasonable price. Nuclear energy has proved to be an extremely reliable and stable form of electricity. Because nuclear power plants are only shut down for refueling every two years or so, they can provide an around-the-clock “baseload” supply of power to the people.
4 Comments
I have seen some research showing that offshore wind turbines consume as much or more energy in their estimated 20 year life cycle, in manufacture, construction and maintenance, as they generate. I have tried to find a link on Google, but it is buried deep in the search results somewhere. That’s not surprising because Google is known to be pro green energy.
There is no correlation between CO2 concentrations and world temperatures. In the period between 1940-1979 the earth’s temperature cooled by 0.2 Celsius while CO2 increased at a higher rate than in previous years so how can it be said that CO2 drives temperature? The scientists have no idea of what proportion of the 1 C of global warming is natural.
This only goes to show that wind turbines are worse for the environment than coal, except for hydro and Nuclear power, fossil fuels remain the only viable power source in the foreseeable future.
They renewables could not exist without fossil fuels used in their manufacture, transport installation etc. If they want fair dinkum fossil fuel free power then the only alternative is Nuclear power but that would mean the end of global warming / IPCC and they are not likely to go quietly.