Nuclear Phaseout? — A trick in the 15% Scenario

In the previous post, I talked about the three Options for Energy and the Environment presented by the Japanese government. From now on, I want to dig into a little bit deep into the content of the Options.

Although this is not exactly my favorite topic, let me first deal with the issue of nuclear because this is the dividing factor of the three Options and is currently at the center of people’s attention.

As I mentioned in the previous post, there are three scenarios for nuclear’s share in 2030.

  • 0% by 2030
  • 15% by 2030
  • 20-25% by 2030

There are 54 nuclear reactors in Japan (of which, 4 are already to be scraped due to the Fukushima accident). And the current (2010, pre-Fukushima) share of nuclear in electricity is 26.4% (or 30.8% if you exclude cogeneration and onsite generation from the total).

So what do these scenarios tell you?

According to government’s own explanation, the 15% scenario is described as a scenario of gradual phase out of nuclear power plants. The “15%” is said to be a milestone in 2030 when each of nuclear power plants is phased out after 40-year lifetime (this “40-year lifetime” is a new policy that was adopted by the government).

But this is not exactly true. To make a long story short, the only “0% scenario” assumes actual reduction of nuclear power plants and both 15% and 20-25% factually assumes new construction.

There is an interesting slide prepared by the Agency for Natural Resources and Energy (ANRE) [in Japanese]. Below is a rough translation of the table in the slide. The table basically shows the background assumptions for certain % share of nuclear in 2030. For example, to get 13% share in 2030, you need to assume 40-year lifetime, no new additional construction and 70% of capacity utilization rate (load factor).  CUR stands for capacity utilization rate.


Snapshot of Year 2030 Reactor Lifetime Assumption
40 years 50 years 60 years
Elec Generation
Share Elec Generation
Share Elec Generation
(1) No new reactor CUR 70% 130.2 13% 218 22% 283 28%
CUR 80% 148.8 15% 249.2 25% 323.4 32%
(2) One new reactor CUR 70% 139.4 14% 227.2 23% 292.2 29%
CUR 80% 159.3 16% 259.7 26% 333.9 33%
(3) Two new reactors CUR 70% 148.6 15% 236.4 24% 301.4 30%
CUR 80% 169.8 17% 270.2 27% 344.4 34%

What you can see from this table is, if you want to get 15% share, you need to assume AT LEAST either:

  1. 40-year lifetime, no new reactors, 80% capacity utilization rate,
  2. 40-year lifetime, one new reactor, 80% capacity utilization rate, or
  3. 40-year lifetime, two new reactors, 70% capacity utilization rate

However, these assumptions have three problems.

1) even in the case of “no new reactors,” it is assumed to restart the 6 remaining nuclear reactors in the area of Fukushima: Apart from the 4 completely damaged nuclear reactors, Fukushima Prefecture has 6 more nuclear reactors.  2 in the same site with the damaged 4 (Fukushima No.1) and 4 in a different power site (Fukushima No.2)).  You can see a map of the location in page 43 of this document. This is highly unlikely to be accepted by the people in Fukushima.

2) 70%-80% Utilization rates are not realistic: in the recent years, the average utilization rate of nuclear power plants in Japan has been around 65%. Increasing the rate means less time for regular inspection. This is again, highly unlikely to be accepted (nor desirable) in the post-Fukushima context.

3) There may be some overestimation: if you add up all the capacity of nuclear power plants in Japan and do calculations under the same assumptions, the figures for these cases would become a few % lower than the figures above.   For example, if you run the numbers for the first case, it will only produce 14%.

All of the three options assume the reduced numbers of nuclear reactors in Japan compared to the current level but 0% Scenario is the only one that goes in the direction of actual phaseout.


Three “Options for Energy and the Environment”


Which way?

After the Earthquake and Fukushima disaster on March 11, 2011, Japanese government started a review process of its energy policies.

Under the Energy Policy Basic Law (Note: literal translation of the name), the government is asked to set up a strategic plan on energy policies every three years. The government just did that in 2010 and adopted the new “Basic Plan on Energy” (Note: the same as above) in the same year (if you want to see this old version, you can read the summary here; it says “Strategic Energy Plan of Japan”). However, in light of the disaster, it started the process to re-change it.

After almost one year of discussion at governmental advisory committees, the governmet presented the so-called three Options for Energy and the Environment on June 29th.

Those three options are basically divided by share of nuclear in electricity mix in 2030 but these also include other details too (e.g. renewable percentages, fossil fuel mix, etc).

You can see government’s own explanation in the slides here.

There are lots of thing I want to talk about these so-called “Options” or scenarios. However, let me first focus on implications for climate targets of these Options because they are devastating.

In summary, climate targets for the three Options like like the following:

  • 0% Scenario: 0% nuclear in 2030 => 7% GHG reduction below 1990 by 2020, 23% by 2030
  • 15% Scenario: 15% nuclear in 2030 => 9% GHG reduction below 1990 by 2020, 23% by 2030
  • 20-25% Scenario: 20-25% nuclear in 2030 => 10-11% GHG reduction below 1990 by 2020, 25% by 2030

You might wonder why the difference between 0% scenario and 15% or 20-25% secnarios is not so big. It is because both renewable and energy efficiency assumptions are enhanced in case of 0% scenario. I will talk about those assumptions later.

The current Japanese target for GHG reduction is 25% reduction below 1990 by 2020. It was announced before the Copenhagen conference in 2009 and was also submitted to the Cancun pledges (though, with strong conditionality).

It should be noted that the figures in these Options are expressed as pure domestic reduction while the 25% reduction was understood to include forest sinks and offsets. If you assume the same level of use of those measures as in the Kyoto’s first commitment period, Japan would use 3.8% and 1.6% of sinks and offses respectively. Hence you can say, 0% Scenario Option is actually 12.4%; 15% Scenario Option is 14.4%; and 20-25% Scenario Option is 16.4%.

Nonetheless, these are significant regress from the original 25% reduction target. When the UN negotiations are talking about “raising ambition,” this won’t look nice.  If any of the three Options is adopted as the way forward as it is, then it is very likely that the climate target is also revised accordingly.  In short, we are on the verge of losing the 25% reduction target.

The government is now holding some sort of public consultation process and origanlly planned to conclude by the end of August.   I said “some sort of” because the public consultation process has some problems.  I also said “originally planned to conclude” because now it is getting likely to get postponed at least by Fall due to the problems.

Anyway, in a nutshell, from climate perspective, these three Options put forward by the government is not exactly encouraging. I hope to dig into more in the next posts.

About this blog

I’ve been wanting to do this for long time but, somehow, I’ve been failing to start it (mostly because I’m a lazy person).

The purpose of this blog is to provide my personal views on climate and energy policies in Japan. Because there are not many information sources of this kind, I thought there might be some appetite for this kind of blog out there.  Sometimes I receive questions from foreign journalists and almost all of them are having difficult time following what’s happening in Japanese climate and energy policies.   It is not just because of the obvious, language barrier but because the information is very difficult to find.   In fact, even if you were a Japanese, it would be difficult to find information related to climate and energy policies.

My views may be biased because of my occupation.  But they will be better than nothing.

I have to say the views expressed here are totally personal and have nothing to do with the organization’s official views.

I’ll try to explain things so that people outiside Japan can understand the context.  But I guess it will be difficult as I live in Japan and don’t understand what foreign people don’t understand.

So, if you have any suggestions, please let me know.