No more nuclear reactors

April 18, 2011 4:45 PM

Pumped-storage hydroelectricity (PSH) is key when discussing the electricity supply for this coming summer.

There is constant discussion over the energy generation capacity with and without PSH. Though neither Tokyo Electric Power Company (TEPCO) nor the Ministry of Economy, Trade and Industry fully articulates the generation capacity of the PSH method, I am personally surprised by how much power it can generate.

Why does PSH have so much potential?

Nuclear power generation has two limitations. One is the installed capacity, meaning the maximum amount of power that can be generated. Needless to say, we cannot generate more than this capacity. The other, more crucial limitation is the minimum demand for electricity during the night.

Nuclear power generation, due to its structure, is incapable of fluctuating its output; rather, it produces a constant amount―the "base load." Consequently, power companies deal with increased demand by utilizing thermal and hydro power.

Inconveniently enough, nuclear power generation cannot lower its output during times of decreased demand. Let's say the maximum power consumption during the day is 100, the minimum consumption at night 50, and the nuclear generation capacity 70. If the nuclear reactors constantly produced their maximum of 70, it would exceed the minimum consumption level at night without the firms being able to adjust the output accordingly. Hence, the nuclear reactors would have to operate at output 50 in accordance to the minimum consumption.

It is the PSH method that can solve this inconvenience. Referring to the example above, if nuclear reactors generated 70 units of energy, it would result in an excess of 20 during the night time. By building PSH plants, we could utilize this 20 to pump up water during the night and use that water for power generation during the day.

Therefore, nuclear energy and PSH complement each other. (The Ministry of Economy, Trade and Industry and power companies consider the two as separate in order to exclude the PSH construction fees from the nuclear power costs.)

This is why PSH has so much unnoticed potential.

The claim that 80% of energy in France is generated by nuclear power is slightly incorrect. Even France cannot operate nuclear reactors at an output above the domestic minimum consumption level. France, however, manages to generate nuclear power at their maximum capacity by selling excess power to surrounding countries such as Germany. The amount of nuclear energy France generates and the amount of nuclear energy it consumes are two different stories.

The Ministry of Economy, Trade and Industry, electric power companies, and pro-nuclear energy politicians have sought to increase nighttime power consumption one way or another - all for the purpose of increasing nighttime consumption in order to promote the expansion of nuclear reactors. This is why they don't call it a "peak-cut," but a "peak-shift," which would raise the minimum consumption during the night. This is their ultimate goal.

That is why when people propose the simple solution of conserving daytime energy to be used at night these same politicians knowingly smirk because they know that is not the case.