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| Timothy Maloney |
You’re celebrating the shutdown of Vermont Yankee nuclear plant. Presumably you intend to replace its 620 megawatts with wind and solar, thereby improving the condition of the biosphere.
Here’s the rub: the condition of the biosphere doesn’t respond to good intentions expressed in words; it responds to technical ideas expressed in numbers.
Let’s look at five numbers that accompany wind and solar replacement of Vermont Yankee.
- Amount of steel required to build that wind and solar;
- Concrete requirement;
- CO2 emitted in making that steel and concrete;
- Money spent;
- Amount of land taken out of crop production or wildlife habitat.
To make up Vermont Yankee’s 620 MW then, we’ll need:
- 310 MW(average) for wind
- 155 MW(avg) for PV solar
- 155 MW(avg) for CSP.
The North America wind capacity factor is about 24%. That is, a wind turbine produces an annual average of 24% of its peak capacity – what it can produce when the wind is blowing nicely. So to obtain 310 MWavg we must build
310 MW ÷ 24% (0.24) = about 1290 MW peak capacity
Selecting the General Electric model 2.5xl wind turbine (Shepherd’s Flat farm in Oregon), with 2.5 MW peak capacity, we will need this many turbines: 1290 MW ÷ 2.5 MW = 515 turbines.
Each model 2.5xl uses 390 tonnes of steel and 1080 tonnes of concrete. Its installed cost is about 4.7 Million dollars for erection of the tower and connection to a neighboring transmission line. That $4.7 M does not include the cost of the land, bought or leased; nor does it include the cost of a branch transmission line, if needed, to make connection to an existing line.
With land costs and branch connecting costs included, let us say about $5 Million per turbine.
Steel production emits about 1.8 tonnes of CO2 per tonne of steel; concrete production emits about 1.1 tonnes CO2.
So each turbine, in manufacture, produces this much CO2: Steel: 390 x 1.8 = 700 t CO2; Concrete: 1080 x 1.1 = 1190 t CO2; Combined: 700 + 1190 = 1890 tonnes CO2 per turbine.
Each such turbine needs land area of about 0.3 square kilometer – about 500 x 500 meters.
So for 515 turbines, here’s the tally:
- Steel: 515 x 390 t = 200 thousand tonnes
- Concrete: 515 x 1080 t = 560 thousand tonnes
- CO2 emitted: 515 x 1890 t = 970 thousand tonnes
- Cost: 515 x $5 M = 2.6 Billion dollars
- Land: 515 x 0.3 km2 = 155 square kilometers (12×12 km, 7×8 miles)
The North America solar capacity factor is about 17%. It’s worse in the northeast, but let’s say 17% anyway.
To obtain 155 MWavg we must build 155 MW ÷ 0.17 = 910 MW peak capacity.
Working from the Aqua Caliente PV project near Yuma Arizona, here are the numbers:
- Steel: 110 tonnes per megawatt of peak capacity. 110 t x 910 MW = 100 thousand tonnes of steel
- Concrete: negligible
- CO2 emitted: From steel:100 e3 t x 1.8 t CO2 = 180 thousand tonnes;
- From panel manufacture (at 130 tonnes CO2 equivalent per megawatt peak): 910 MW peak x 130 t /MW = 120 thousand tonnes CO2eq; Total: 180 + 120 = 300 thousand tonnes CO2eq
- Cost: Aqua Caliente is costing $4.5 M per MW peak . So $4.5 M x 910 MWpk = about $4 Billion.
- Land: PV solar needs about 0.025 km2 per megawatt peak. 910 MW x 0.025 km2 = 23 km2 (4.8×4.8 km, 3×3 miles)
Again 155 MWavg at 17% = 910 MW peak
Working from the Andalusia Spain plant that connected to the grid in 2009, called ANDUSOL1, here are the numbers.
- Steel: 170 tonnes per MW peak. 170 t x 910 MW =150 thousand tonnes
- Concrete: 870 tonnes per MW peak. 870 t x 910 MW= 800 thousand tonnes
- CO2 emitted: 150 e3 t steel x 1.8 t CO2 + 800 e3 t concrete x 1.1 t = 1.2 million tonnes CO2
- Cost: Removing from the tally the cost for 7.5 hours of molten-salt energy storage, the generation equipment itself at ANDUSOL1 cost about $7 M per megawatt peak.
- So for our CSP needs, 910 MW x $7 M = about 6 Billion dollars.
- Land: CSP solar needs about 0.012 km2 per megawatt peak. 910 MW x 0.012 km2 = 11 km2 (3.3 x 3.3 km, 2 x 2 miles)
- Steel: 450 thousand tonnes; that’s 0.6% of our U.S. total annual production, JUST TO REPLACE ONE SMALLISH PLANT.
- Concrete: 1.4 million tonnes; about 0.2% of our annual production
- CO2: 2.5 million tonnes
- Cost: about 12 Billion dollars
- Land: about 190 square kilometers (14 x 14 km); that’s 73 square miles, larger than the District of Columbia, JUST TO REPLACE ONE SMALLISH PLANT.
Sure it’s easy to piggyback on those baseload generators with your intermittent, poor quality, non sine-shaped, non 60-Hertz, electrical energy. The transmission circuit (voltage between wires) is sine-wave stable only due to the low-resistance thick copper wires in the ac alternators that are attached to those steam turbines. Which work 24/7.
With a stable transmission circuit like that, anybody can assert his little bit of extra energy into the mix without causing much disruption. But don’t try that without a stable baseload – it won’t work.
Other Alternatives: Generation 3+ PWR
Well, if we want to shut down a 40-year-old Generation2 boiling water reactor, we could replace it with a Generation3+ pressurized water reactor, the Westinghouse /Toshiba model AP1000.
It produces 1070 MW baseload, nearly twice the output of Vermont Yankee. Normalizing 1070 MW to Vermont Yankee’s 620 MW, the AP1000 uses:
- Steel: 5800 tonnes – about 1% as much as wind + solar.
- Concrete: 93,000 tonnes – about 7% as much.
- CO2 emitted: 115 thousand tonnes – about 5% as much
- Cost: We won’t know until the Chinese finish their four units now abuilding. But it will sure be less than our “levelized” cost because you can betcherbippy the Chinese State Nuclear Power Technology Corporation isn’t really paying any bank interest or insurance premiums or licensing and inspection fees.
They’re going to find out what it actually costs just to build one. That will be the meaningful number. Why should we let the banks and insurance companies stick their noses into our energy supply? The lifeblood of our society.
- Land: The AP1000 needs about 0.04 km2 for the entire plant site. (200 x 200 meters). Smaller than CSP by a factor of 2000. Smaller than PV by a factor of 4000. Smaller than wind by a factor of 13,000.
Or, we could all get on board the thorium molten salt energy bandwagon. We at the Thorium Energy Alliance are morally certain that our idea will beat even the Generation3+ model AP1000 by wide margins in all 5 aspects – steel, concrete, CO2, dollar cost, and land.
See http://www.thoriumenergyalliance.com or http://www.dirkpublishing.com or http://www.timothymaloney.net.
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About Timothy Maloney
Timothy Maloney is a retired community college professor, in the fields of electronics and machine control. He is inventor of "A Digital Method for DC Motor Speed Control" (1974). IEEE Transactions on Industrial Electronics and Control Instrumentation, February 1976, Volume IECI-23. He is the author of Modern Industrial Electronics (now in its fifth edition) and other books.
He is an advocate for advanced thorium reactors, especially the Liquid-Fuel Thorium Reactor (LFTR) technology. Maloney is available for speaking or slideshows to any interested group.
Maloney wrote a rebuttal to someone who was celebrating the demise of Vermont Yankee and expecting to replace it with wind and solar energy. He sent his rebuttal to a few people (including me) by email. I asked him if I could use that email as a blog post, and he graciously gave me permission.
