Japanese energy decision time

The news has been full of the Japanese problem.  Reuters  and others have been all over Yahoo this week and related news outlets.  Not the Fukushima fuel melt problems a couple months back, those were disturbing enough, but perfectly predictable.  The problem stems from the review of their power generation options.

The Japanese are in a tough position.  Fortress Japan is wonderfully isolated by water from all human attackers, sort of like Fortress America. This made it a good place to form a coherent society.   But, unlike FA, FJ has no abundant natural resource to power a modern civilization.  No uranium for their reactors.


21 sites hold 51 Reactors

Currently, they have a thriving society based on 21 sites holding 51 power reactors that supply an average of 30% of their power needs.

I show the reactor sites on this map (base map from Wikipedia Commons as shown).  There are 2 sites marked by × where the reactors are not yet operational.

The WNA states that when 2011 began, the plan was to have an additional 50 reactors operational by 2030.   These were to produce 50% of the total electric power needed.

The numbing result of our Nuclear Decisions-2 was that the current style of reactors (pressurized water, boiling water and liquid metal fast neutron types) promise many unhappy core melts to come.  These things occur in chaotic conjunction of multiple unplanned disasters.  (Example: Mag 9 earthquake + tsunami.  Or, think of sleepy, bored control room operators with repaired valves installed almost correctly; then add the burst of a corroded water conduit burst.  Things like that.).   Nuclear Decisions-3 indicated that the once-through procedure that generates spent fuel rods is a prescription for long term disaster.   Nuclear Decisions-4 showed that the world  does not contain enough uranium ore to let countries replace hydrocarbon fuel with nuclear.  There may be solutions, but using business-as-usual technologies will not work.

Every reactor in Japan will need refueling maintenance during the coming 12 months.  The hope was to put the unit in safe mode at that maintenance time and close the doors. This puts an end to the 50 new units and essentially an end to Japanese reliance on nuclear power.   In one year all plants would go “dark.”

I have to applaud the Japanese decisions.  But, as Reuters points out (see lead link),  the timescale is devastating.

Reactors generate 30% of Japanese electricity that powers the industry that pays the workers who pay the taxes.  Conventional plants could makeup no more that 60% of that loss. And that is if they all run FULL out, a non-optimum situation leading to certain early equipment failure.   Quick calculation — 60% of 30% total is 18%, leaving a shortfall of about 12% in current power capability.

Suppose that, for safety, they power down all reactors tomorrow. The day after would be economically disastrous.  Japanese industries are threatening to pull out of Japan altogether and head for undisclosed locations that can power their machinery.

Suppose you were a Japanese leader: How would you make the power decision?  Liquified natural gas?  This has almost the energy density of gasoline and would help.  But does Japan have sea port space to handle the shipments?  They certainly do not have the plants standing ready to start burning natural gas.  This is a 5 year solution, if they waive all regulations and just push for the goal.  The same argument is made for all potential fuels.  Logistics do not exist and the hardware infrastructure would not be available for years.


Molten salt solar heat uses array of mirrors

Solar?  There are several prototype huge solar power generators being built, let’s scale from the Torresol plant in Spain. This will generate 20 MW using a plot of mirrors covering 185 hectares of land.  185 ha = 1.85 km2 = 0.714 miles2 for 20 MW.  Use 0.093 km2  per MW generated.    According the the U.S. EIA, Japan used 964 G kWh of electrical power in 2008 (last year reporting).  30% of this is to be replaced by solar.    Solar must generate 0.3× 970 GkWh in one year (= 24×365 = 8760 hours)  or  0.3×970×109 kWh/8760  = 33 M kW = 33,000 MW of power, approximately.  Room needed: (33 000 × 0.093 =) 3 100 km2 for the solar generator system.  The Torresol plant stores excess energy in underground molten salt tanks and can continue generation for more that 15 hours after the sun sets.   I do not know the ratio of peak demand to average demand but I would think it might be  a factor of 3.   This puts the land need at 9 000 km2.

Japan could put the solar facility on a square of land 95 km (59 mi) on a side to generate the needed power.  This would not be located in a single place, but it gives an idea.  Concept is “back of the envelope” feasible.  They could probably do solar to replace the current nuclear, if they wanted to live with occasional brown down times when the sun has been MIA for 24 hours or so.

Wind?  They could do wind, too.  Japan is all coast and have great gusts.  But wind power is noisy and kills birds.  Maybe off shore?   All this is definitely at the prototype level of development, do not pin your country’s future on such.  If they started today, my quick guess is 10 years to full implementation, solar or wind.

click for a list our fission-related discussions

This is not just an idle exercise.  They must do something, and they do not want to be the Future’s nuclear disaster theme park.   I do not see a quick fix and my recommendation would be to do a bit of each.  LNG will become very expensive when oil is no longer holding hydrocarbon costs down,  so this should be only a fraction of the solution.  Coal is truly dirty with many poisons released in its burning.  Read expensive to mount effective pollution controls.   Think about what you would do if you were the Emperor of Japan …  someone is.

Charles J. Armentrout, Ann Arbor
2011 Jun 9
Listed under   Technology    …   Technology > Fission
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About LastTechAge

I am a physicist with years of work in fusion labs, industry labs, and teaching (physics and math). I have watched the tech scene, watched societal trends and am alarmed. My interest is to help us all improve or maintain that which we worked so hard to achieve.
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