How many wind turbines are needed to power Britain?

Answer 1

The population at the moment in Great Britain is: 61,838,154 according to Google Public Data stats.

The approximate "peak power" consumption would therefore be: 309.191 GWh based on 5 kWh per person. This takes into account commercial/industrial & residential use per person. Many factor a home at around 3kWh divided by the average people per home but they forget to factor in the infrastructure to support the community such as dry cleaning, food stores, gas stations, etc...

Divide the Total GWh Peak of 309 by 1.5 MWh of the average large Turbines (propellers) and we come up with: 206,127 units to provide 309,191GWh for GB usage in the middle of the day with everything turned on and full production.

Factor in an approximate cost of $2 million per unit we arrive at a project cost of: $618,381,540,000. That $618.3 Billion.

Now factor in cost of Power Transmission which some quotes are as low as $1.5 million per mile and up to $10 million per mile for a California project. So we'll go with $2 million to be kind. If we created this project off shore, with 206,000 units, yikes, we might break the project into say... 50 projects of of 4,150 units each. Thus if the average offshore distance was 5 miles, we'd have a total of 5 x 50 = 250 miles x $2 million = $500 million for transmission to get to the shore and hopefully tie into a main point in the construction grid.

Add in a 10% contingency factor and we're over $700 Billion for the cost of the project. Using the same calculation factors puts the cost of producing peak power for America with wind at over $7 Trillion with over 1.7 billion units and around 2 billion acres of land.

Other factors: The projection of 1.5 MWh is generated when the wind is at 14 mph. Finding locations on our planet where wind averages 14 mph 24/7 is....? Wind maps show average wind speeds around the world with averages around 3 to 4 mph. The wind belt from the Texas panhandle up through the Dakota's shows around 8 to 9 mph. Thus the true results of these projects is worth pursuing. Projected power of a wind farm vs. reality once constructed and tested over a year or two.

My question would be: Is this the answer or are we being over promised by sales people making a ton of green on green? For example: Shepards Flat Oregon 845 MWh GE Wind Farm - $2 Billion project covering 30 sq miles of pristine land. That $2 billion will create a total of 35 jobs once in operation and kill almost 2,000 birds, including eagles, yearly.

Vestas is working on a new 7MWh unit with a total diameter approaching the length of two football fields. Cost factor still unknown? Impact on birds, downwind effect, other? China is working on a 10MWh unit! They're coming!

I wonder if we put enough of these monsters up might we slow down the rotation of the planet and every would fall off? After all rotation speed is what creates Earth's gravity right?

As you can tell I believe there is still a better solution!

Comments certainly welcome!