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theWatt Podcast 75

Panel discussion podcast with Mark Seall, Rod Adams, Robb Worthington and Ben. Topics include carbon taxes vs cap-and-trade policies, OECD Environmental Outlook, nuclear power in the UK, carbon limits on cars in the EU, $106/bbl oil.

Topics/Show Notes:

Wind turbines and coal power

Ok, so, how many wind turbines would it take to replace a coal power plant? Well, I underestimated...but I also think Rod overestimated.

Here's a more accurate calculation.

First of all, how much energy does a coal power plant produce? Well, in the US there are 1,493 coal generators with total nameplate capacity of 335,830MW or 225MW/coal power plant (

When talking about energy produced from wind power, we also have to factor in that the wind isn't always consistent, and on the low side, wind turbines will have a 20% capacity factor. So, a 3MW turbine would probably have an effective rating of 3*0.2=0.6MW, or as high as 1.2MW with a 40% capacity factor.

So, you would need 375 wind turbines (each rated to a max. power of 3MW) with a 20% capacity factor to replace a 225MW coal power plant or 187 wind turbines with a 40% capacity factor.

Now, most new coal power plants are probably going to have a nameplate capacity of 500MW (maybe even higher), not 225MW. So, in this case, we would need 833 wind turbines (3MW turbines at 20% capacity factor) to replace that 500MW coal power plant. BUT, wind turbines can also go up to 5MW now. So, if your wind farm had 5MW turbines, then you could replace a 500MW coal power plant with 500, 5MW turbines (with 20% capacity factor) or 250 5MW turbines with a 40% capacity factor.

Re: theWatt Podcast 75


I guess I did exaggerate a bit. The bottom line of my below computations and assumptions is 1280 turbines, not 2000.

While I accept the numbers that result from your assumptions, I just wanted to provide mine. While there are a lot of smallish coal fired power plants still in commission in the US, most of the projects that I have been reading about recently are closer to 800-900 MWe per unit.

I have heard about 5 MWe wind turbines; they are physically imposing machines. Depending on the wind pattern in their local area, they will have their turbines mounted somewhere between 90-120 Meters above the surface and have blade diameters in excess of 120 meters. These machines are probably not the ones that you saw located next to what appeared to be coal fired power stations; they would dwarf all structures at most coal plants except the cooling towers and stack.


Therefore, my mental gym number for wind turbine size is 2 MW with an annual capacity factor of 25%. Quite a few land based turbines are still in the 1.5-2.0 MWe class since they are easier to transport and install than the more massive machines because they need smaller, more readily available cranes.

The average coal capacity factor in the US is about 70%, but newer plants tend to operate in excess of 80% - the average is brought down by some older plants that only run during high usage seasons.

If the coal plant is 800 MWe and operates at 80% CF, its annual electricity production is 5.6 Billion KW-hrs.

It would take 1280 of the nominal 2 MWe machines to produce that amount of electricity, but the big difference for the grid operator is the degree to which that production can be scheduled. The wind blows when it wants to, coal production can generally be more predictable.

Mind you - I am not defending coal - it is a messy substance that just happens to be useful to produce something that humans apparently want badly enough so that we put up with the mess that results from burning about 6 BILLION tons of coal each year.

One other comment about wind turbines - though many people talk about wind as something local and distributed that shifts power from the hands of large corporations, when they perform economic computations to talk about how cheap wind power is they assume the use of massive machines produced by companies like GE, Siemens, and Vestas. None of those companies seem to be in need of taxpayer subsidies or market mandates anymore than do nuclear plant producers.

Separate topic - Ben; thank you for inviting me onto the show. It was a lot of fun to engage with such a well informed group.

Re: theWatt Podcast 75

It seems like this is a frequent thought these days. From my web site:

Factoid: Using the very generous American Wind Energy Association capacity factor of 33%, the 1,800 megaWatt Big Bend plant produces as much real-life electricity as 6,350 170 feet in diameter VESTAS V-52 wind turbines. Just the United States' coal-burning power plants alone combine to make as much real-life electricity as 1,059,000 170 feet in diameter VESTAS V-52 wind turbines. VESTAS is installing wind turbines at the rate of one every 5 hours. It would take them 604 years to install 1,059,000 wind turbines.

Re: theWatt Podcast 75

The land area requirements are also quite large. Roughly 0.1 sq km per MW of nameplate capacity, so, for an 800MW farm, you'd need 80 sq km. I think that's another reason for putting them offshore though. Offshore also has higher capacity factors as well.

Interesting. I did a podcast interview with an wind power expert who didn't see a need of putting turbines offshore though: /node/96 (I also have a transcript for that):

Ben Kenney: What are your thoughts for things like offshore wind farms in North America? I mean the Cape Wind Project is having a lot of problems lately. Well, they have had a lot of problems since they have started, since they have proposed the Cape Wind Project. Do you think offshore will be a big player?

Paul Gipe: No, we do not need offshore in North America. Sure, we should not exclude offshore where offshore makes sense, we should not exclude it. Offshore Toronto, for example, certainly should not exclude it. Offshore Rochester, New York, offshore Detroit should not exclude, offshore Kingston should not exclude that, offshore of Queens University certainly should not exclude that, but we are land rich in North America and it is simply a lot easier to put the wind turbines on land and offshore. I have argued for many years, they are on record in my books and in my articles that offshore is not a panacea for what ails wind energy. The big issue with wind energy is will the people accept it? Will the public accept it? Some will, some will not, of course, unlike nuclear power, which can be shoved down people’s throat by some central decision making by some government whether it is in Toronto or Washington, DC. Wind energy has to be accepted by the people who live nearby and if it is not we will not do it and the early push for going offshore was the belief that going offshore was a panacea. They are out at sea, they cannot see them, nobody is going to care. Of course, that was bogus at the very beginning and you see in the Cape Wind case of course it is bogus because you do not want Canadiens and the mansions there they do not want to look at windmills. Even if they cannot see them, they know they are out there and well I mean would you want to go to [20:45 unintelligible] if you think there is a windmill offshore. Of course, you would, but maybe the Canadiens do not want to live with it. Those kinds of people have a lot of political influence.

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On the topic of wind power, a few thoughts: land use, intermitancy, cost, time frame.

1. The requirement for land is large. I`m not sure i would term this land use. In what sense is the land used? Crops can still be grown, cattle still reared, building built etc., In europe ofshoore is going to be vast, in the US it probably will be at a later date but you have a lot of land!

2. HV DC lines can be used to increase the consistancy of power supply. It is common for local wind power to be very low but extremely unusuall for the same to be he case 1000 miles away. Lots of work is being done on this for a North Sea power grid and enormus wind farm. UC Berkeley are doing some great work on demand damping, this combined with micro renewables offers great potential for renewable energy penetration in a smart grid.

3. If fossil fuel subsidies where ended i think wind would compete without the RPS. If you introduced a cap and trade scheme to internatise the cost of carbon i'm pretty sure it would out-compete all fossil fuels.

4. Wind power is an emerging technology. Evert new wind power factory represents not an increase in next years expected wind power output but an increase in the increase. Exponential growth in wind power is the reason that it is takens seriously as an investment opportunity. By the way, do you have a chess board? I would like one grain of rice on the first sqaure, two on the second four on the third etc.. Wind power can be deployed more quickly than practically any other generating unit.

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Wind farms do have land that is fully occupied with the turbine foundations, the supply roads, and the transmission infrastructure.

HVDC lines are only economical for large power transmission and there is not a big infrastructure of those lines in the US. There is especially not a big infrastructure in those vast empty areas that wind farm promoters talk about filling to supply "all the electrical needs of the US".

Wind might be "cheaper" than fossil fuels when it is available, but it will not compete with them most of the time since it CANNOT perform the same tasks of providing weather independent power for transportation, heat, industrial uses, and important home uses like big screen TVs at the time that the game is scheduled.

Wind power is not emerging - humans have been capturing the dispersed and fickle power source for thousands of years. Billions of us have figured out, however, that we want something better and more reliable.

If you believe in continuing exponential growth of anything, can I also sell you some waterfront property in Arizona or persuade you to put your teeth under your pillow for a nice shiny dollar in the morning?

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On wind power and exponential growth:

One of the things that i studied at university was microbiology. You start theone day wih a few thousand microes on a swab and a few days later they become visible, followed shortly by complete saturation of thier solution and die off from metabolite poisining or consumed resources. I clearly dont believed in persistant exponential growth.

However, the nature of exponential growth is relavent to the comment above about the number of years it would take to install a qauntity of wind turbines.

I dont see why growth couldnt continue untill saturation of the grid--that still a hell of a long way some areas >20% has been acieved but i`m not sure what the curent us grid could cope with--what is clear however is that the time argument is bogus.

I agree that HV DC lines are costly, they may ake subsidies and would advantage all intermitant sources of power, they may require almost the level of subsidies that nuclear power needs for its insurance and waste cleanup. However, i`d rather look to a clean low carbon future of distributed rather than concentrated nature. The concept of smart grid is gaining traction, and in the UK we have small examples, germany have done much better, US research on automation and time signaling is groundbreaking.

Re: theWatt Podcast 75

I am not really sure why I am spending so much time in an argument about wind. It is just a minor distraction since the real competition for atomic fission energy systems is fossil fuel combustion systems. Even after thousands of years of effort, the amount of power produced by wind is a tiny fraction of 1% of the world's primary energy supply. It has experienced some recent fast growth, but that has largely been the result of mandates, subsidies and clever marketing by companies like General Electric (GE) - which supplies nearly 50% of the US market for turbines.

For all exponential growth systems, there are many factors that eventually limit the growth to a much smaller rate.

With wind, grid stability is only one factor that may come into play, but it is probably the least of the worries. Well before you hit a limit of grid stability, you will run into turbine availability, availability of good sites, local opposition, transmission system interconnection limits, material availability, lack of adequate cranes, lack of physical access to sites, dissatisfaction with the rate of return, etc.

You mentioned the "subsidy" that nuclear gets from "insurance and waste cleanup". Can you tell me just how much the insurance has cost the taxpayers? In the UK, there is a pretty large projected cleanup bill, but a major portion of that bill is for weapons complex cleanup, and is not strictly related to power production.

In the US, the waste costs for nuclear power production systems are all internalized - they are covered by the revenues associated with the sale of electricity. The market value of the electricity produced by a nominal 1000 MWe nuclear power plant in the US last year was nearly $500 Million (90% CF, market price of electricity of $60 per MW). Those plants paid a huge tax bill, contributed nearly $8 million each to a permanent used fuel fund, paid for all of the costs of packaging, transporting and storing low level waste, paid excellent salaries for 500-800 permanent workers, supplied reliable, emission free energy for about a million people, and paid their own insurance bill up to the legal limit. NONE of them has ever made a claim against the "subsidized" insurance system.

Now tell me how the competitive fossil fuel industry handles its deadly waste.

BTW - if you want to see an exponential rate of growth, take a look at the curves related to the production of electricity by nuclear power plants in the world in the period from 1973-1996 and then think about what the people in the marketing departments at major oil companies, coal companies, railroad companies focused on transporting coal, and government completely dependent on fossil fuel sales were doing as they watched that rapidly expanding competition.

Re: theWatt Podcast 75

Why discuss what a wind farm looks like? Take a look on Google Earth or one of the other global view sites.

Clean energy progress so far:

IPCC data says in 2004 the world used 468 Exajoules of energy. So far, man's worldwide efforts over the last 20+ years to produce clean energy from wind, solar, geothermal, etc., add up to about 1/2 of one percent (2.4/468 EJ - see 2004 .pdf). That's practically nothing. Certainly not enough to get us out of Global Warming trouble. Clean power from carbon-neutral biomass, hydro and nuclear was 89.6/468 EJ or 19% of the world's energy. The remaining 80% are CO2-producing fossil fuels.

Above about 6%, wind and solar tend to de-stabilize electrical grids.

1% total fuel efficiency of moving a person in a car

I got an email asking me to explain how 1% of the energy in gasoline goes to moving a person in the car. I saw this calculation in The Zero Carbon Car book but it's also in Amory Lovin's book/report, Winning The Oil Endgame:

It's based on the weight of the car and the weight of the passenger. In Rod's case, since there are more people in the car (and diesel engines are more efficient than gasoline), the total efficiency of moving Rod and his passengers is a bit higher than 3%.

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I will provide a response computation soon. I have to tell you that any quote of Amory Lovins that involves mathematics is immediately suspect for me.

Who can trust a "physicist" who never earned a single degree?


Re: theWatt Podcast 75

Yes, I agree that everything should be triple checked. A lot of people seem to be leery of Amory Lovins. He does have people working for him that have many degrees though.

The numbers actually come from reference 229 in the image that I posted (I guess I should have made the text larger).

Basically, the gist is that the tank-to-wheel efficiency is ~17% (of course there are more efficient cars, but this is an average), but that remaining energy goes towards moving both you and the car. So if the car is, say 1428kg, and you are 70kg, then your weight is 5% of the total weight being moved, which means that 5%*17%=0.8% of the available energy goes to moving you.

Here's a neat image from the DOE showing where energy goes:

I guess we'd have to compare this to other forms of transportation though, like a bus or a train.

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The real fallacy in the logic, is in failing to make a proper comparison between the energy efficiency of personal automobiles that are fully loaded against the alternative of not using an automobile.

If I have a car that can carry four adults each weighing 200 pounds, and that car also includes a trunk that generally carries about 80 additional pounds of gym bags, laptops, and emergency tools for the car, I get closer to 40% of my chosen vehicle weight as payload.

Now, not all of the vehicle weight is designed to make those people comfortable, some of it actually improves the overall efficiency of motion compared to having no vehicle at all. The wheels, for example, are far more efficient from an energy point of view than shoe leather since rolling requires far less work than walking. The car body is also a far more streamlined shape than a human body - much less four of them - which would provide quite a bit of aerodynamic resistance if it was moving at the same speed that a car can move. (My motorcycle riding friends generally get close to the same fuel economy as I do, even though they are in lighter vehicles and cannot carry anywhere close to the same passenger load.)

When all is said and done, the choices that have been made by hundreds of thousands of engineers and millions of customers are not as short sighted as they are portrayed by Mr. Lovins.

While there are lots of oversized vehicles on the road that are often occupied by a single person during the working day, I would bet that a far larger portion of those vehicles than Mr. Lovins would admit are at least occasionally used to carry a much greater load. When we make our vehicle choices, most of us cannot buy one car that fills the easiest need and buy another one to fill the high demand use. (Of course, there are SOME cities where flex vehicle programs might change the dynamic a bit.) It would not be a good use of material or energy resources for everyone to have as many different vehicles as might be needed.

I admit that am a bit defensive about personal automobiles. I have raised a family and never want to give up the memories that we generated by traveling in comfort and safety around the country. The hundreds of millions of car owners in the US are not a scourge, and the engineers that have supplied them have not designed junk.

Re: theWatt Podcast 75

If a 200 pound person is almost 5% the combined weight of a 4,000 pound car and driver, doesn't that mean about 5% of the gasoline was used to push the person?

My 350 pound Vespa and I get a solid 78 mpg around town. 38% of that gasoline is consumed pushing me around. Given that I'm 3 feet tall, should I consider going on a diet?

Wasn't Amory Lovins the originator of nega-logic? Taking Lovin's logic to it limits, a bus would be 50 people on lightweight bicycles holding on to ropes being pulled by my Vespa.

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If a 200 pound person is almost 5% the combined weight of a 4,000 pound car and driver, doesn't that mean about 5% of the gasoline was used to push the person?
No because the gasoline was used to produce heat and mechanical energy (and some smaller parasitic losses like electricity used to power air conditioners/DVD players etc). Only the mechanical energy moves you.

Re: theWatt Podcast 75

Then why not get a electric vespa? You will save both on gas and the environment.

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This is the thermodynamic equivalent of wasting time debating how many angels can stand on the head of a pin.

Issues like safety, reliability, durability, initial cost all may be more important than cost of fuel. Depreciation is the big car expense for most people, not fuel cost even at $4 a gallon.

It all happened before as Oil Crunch #1 played itself out. Chevy Novas and Chevettes sprouted Cadillac badges, Cadillac also devised a V-8 that would first shut down two, then four, then eventually all cylinders - leaving you to call AAA. Then someone remembered diesels had lower pumping losses and presto!, Cadillac held a shot-gun wedding between a Roosa diesel injector pump and their V-8. Made those old GM city busses look clean.

Europe's refineries are set up to produce a lot of diesel (hydrocracking), American refineries use catalytic cracking to produce comparatively more gasoline. More than half the new cars in Europe are diesel with gasoline at $7.50 and diesel a buck less. Diesel would be around $6 a gallon right now if a few more car drivers were as astute as Rod. I smell diesel fever everywhere and hear the sounds of our 10,000+ stripper oil wells creaking back to life once again for a couple of years.

It's deja vu, all over again.


Re: theWatt Podcast 75 - Cap and Trade

The discussion erroneously stated that cap and trade rewards the past's big polluters. This is only true if the credits are allocated based on previous emissions. If the cap and trade program auctions the allocations, whoever pays gets them - and it really punishes those who have no invested in efficiency previously because they suddenly have to make a lot of investments or buy up allocations.

That said, a cap and trade program has vastly great transactions costs - the government has to police the credits. This costs money. A carbon tax is cheaper to impose and may be more efficient. But Americans hate taxes - we would rather pay more in an inefficient program than do something involving a new tax.