Re: Mook's quote about nuclear being a "low grade heat". Is it true?

From: daestrom (daestrom_at_NO_SPAM_HEREtwcny.rr.com)
Date: 06/14/04 

Date: Mon, 14 Jun 2004 22:44:18 GMT

"william mook" <william.mook@mokindustries.com> wrote in message
news:407c5321.0406132056.3a4a9dcb@posting.google.com...
> bigcat@meeow.co.uk (N. Thornton) wrote in message
news:<a7076635.0406131245.7c6a1fa8@posting.google.com>...
> > bri1600bv@hotmail.com (brianb) wrote in message
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> >
<snip>
>
> Don't know what happened to my long winded explanations, whoever
> started this thread seems to have interesting control over what
> appears! I hesitate to repeat such a response - it seems whomever
> started this can quote me out of context and the original doesn't show
> up anywhere. If it does I'd like to be pointed to it! :)
>
> As far as efficiencies of nuclear power plants are concerned, we're
> talking about capital efficiency. I mentioned that before. Thermal
> efficiency enters into it certainly, but that's not all.
>
> And, you've got to look at the entire fuel cycle - not just this or
> that boiler - which I agree can be made quite efficient.
>
> Recall, there's no big reserve of nuclear material we're mining
> already made up for us. We've got to make the fuel in breeder
> reactors and whatnot.

Why do you assume that the nuclear fuel must be made in a breeder? There
are estimates of the amount of fissile material available for many years.

> So, to be cheaper than fossil fuels the capital
> needed for any nuclear power cycle - all of it - has to be cheaper
> (and safer) than the capital needed for the fossil fuel power cycle
> we're now using.
>
> As far as my solar panel technology goes, my website says it all. We
> use a new kind of solar cell technology that can take high intensity
> light and efficiently convert it to power. Increasing the energy
> density in this way allows us to increase the capital efficiency of
> the equipment. In our case, thousands of times. This reduces the
> cost of solar power. Low cost solar power translates to low cost
> energy. If energy prices are low enough from this primary source, a
> number of secondary energy systems can be supported. The same ones
> that could be supported from nuclear power - if it were cheap enough.
>
> For comparison, lets compare a nuclear and solar system.
>
> A nuclear power plant costs around $5 per watt - when the entire fuel
> cycle is included in the cost - creation and disposal as well as use.
> The fuel itself is miniscule per kWh - so let's say that is zero -
> though its not.

Although the last few US nuclear plants that came on line are in that price
range, the advanced designs, with their pre-licensing approvals are
estimated to run in the $2 to $3 per watt range. Unfortunately, economic
studies by private owners/operators suggest it isn't viable to build a new
plant until the price comes down to the $1.50/watt range or until the price
of fossil fuels rises substantially (coal, and NG, not oil prices).

>
> Existing solar power plant costs around $8 per watt - since silicon
> costs around $1,500 per square meter and 200 watts are produced per
> square meter. Of course, there is no charge for sunlight. So, that's
> definitely zero.
>
> So, the nuke is way ahead of conventional solar power. I say way
> ahead, and not just ahead NOT because $5 is less than $8. I say way
> ahead because of utilization. You can run your nuclear plant 24/7 -
> you can only run your solar plant when the sun shines. Now, you can
> add batteries and whatnot, but that only adds to the capital expense
> and doesn't improve utilization of that capital.
>
> Here's how utilization enters into the picture.
>
> Energy is power times time. Kilowatt-hours is energy. Kilowatts - is
> power.
>
> So, a kilowatt of nuclear reactor costs $5,000. A nuclear power plant
> can run 24/7 - say 8,760 hours per year. So, that kilowatt produces
> 8,760 kWh per year of energy - assuming no fuel costs. If the
> discount rate - the time value of money - is 8%, and the lifecycle of
> the nuclear plant is 20 years, we can calculate precisely what the
> annual cost of the capital equipment is $510 - So, dividing 8,760 kWh
> annual production by $510 annual cost obtains 17.17 kWh/$ - inverting
> that obtains 5.8 cents per kWh. THis is more than the fuel costs of
> power production, so converting this energy to fuel would mean
> producing fuel at higher cost than today's fuel.

The licensed lifetime and design of US nucs is actually 40 years. And
several plants have applied for (and been granted) life extensions to allow
operation for a total of 60 years. Despite this, in the late '80's and
early '90's, there were several plants that were shutdown prematurely
(before their license/design lifetime) for economical reasons. FWIW, so
far, no US nuclear plant has actually operated to its full design life
(oldest plant still operating will reach the 40 year mark in 2009).

But these are construction/capital costs only. For a PV system, I'm sure
the O&M costs are comparatively low, but for a nuc they are quite another
matter. The exact $/kwh varies with the size of the plant and it's capacity
factor of course, but a well run plant of typical size can have O&M costs of
$0.017/kwh.

>
> A kilowatt of conventional solar panels costs $8,000. A solar plant
> can run -depending on location- say 2,000 hours per year. So, that a
> kilowatt produces 2,000 kWh of energy per year - with no fuel costs.
> Applying the same discount rate and life cycle - obtains an annual
> cost of $810. Dividing this by 2,000 obtains a cost of $0.41 per kWh
> - nearly 7x the cost of the nuclear power. This is way more expensive
> than the nuke.
>
> In both cases the cost of energy is far more expensive than the cost
> of fossil fuels, so the idea of making fossil fuels from these energy
> sources doesn't make economic sense.
>
> There are about 1,695 kWh of heat energy available in a barrel of oil.
> A barrel of oil costs around $30. So, that's about 56 kWh per $0.018
> per kWh.
>

The heat energy in a barrel of oil cannot all be converted to other useful
forms of energy. Of course, neither can all the electrical energy from a
nuclear of PV system, but the conversion efficiency for electrical energy is
much higher than for heat energy. Perhaps an adjustment should be made here
to account for the differences.

> Working backwards means that we must make energy, and all the means to
> convert it to chemical fuel - at a cost lower than $0.018 per KWh,
> which for a solar collector means a cost per watt of less than $0.35
> ... When the inefficiencies and capital costs of energy conversion
> are added in, the solar panels must cost on the order of $0.10 per
> watt!

This is true only if you insist on taking the alternative forms of energy
such as the electricity from a nuc or PV system and convert it into a form
of hydrocarbon fuel. It's not clear why one would insist on doing this
except for an existing infrastructure to distribute the hydrocarbon fuel.

>
> At these prices - $0.10 per watt - we can make synthetic fuels cost
> efficiently and sell them against fossil fuels - using nothing more
> than carbon dioxide from the air as a carbon source - and sunlight as
> an energy source.

Hmmm, yes and if PV costs could be reduced further, say to $0.05 per watt,
it could crowd fossil fuels right off the market. An interesting
hypothetical. Or do you believe such price levels are attainable?

daestrom

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