I thought we had a panacea now all I have is second thoughts! contd..

Japan is in news again, it seems they had another earth-quake and a tsunami warning! Not good my friends, not good! Not good at all for my Jap friends.

Alright, continuing my thoughts or second thoughts on nuclear energy. Much of what I will write here is influenced by a couple of readings listed below. My interest here is not just nuclear energy but I am more interested in knowing if it is the resource India and other countries should pursue or not.
see:
[1]. Dr. Benjamin K. Sovacool, "Second thoughts about nuclear power", Research Support Unit (RSU)
Lee Kuan Yew School of Public Policy, National University of Singapore Jan 2011
[2].Sovacool, B. & C. Cooper, “Nuclear nonsense: Why nuclear power is no answer to Climate Change and the World’s Post-Kyoto Energy Challenges”, William and Mary Environmental Law & Policy Review, 33, 1, pp.1-119.
[3]. Anshu Bharadwaj,  L V Krishnan,  S. Rajgopal, "Nuclear Power in India: The Road Ahead", Center for Study of Science, Technology and Policy (CSTEP),

So, what are the factors we should think about, what are the benchmarks around which we can discuss, debate and form opinions. What are our goals as a society, as a country and how that is influence by our energy policies.

Before trying to answer these questions - it seems to me that most of us if not all fail to understand how electric energy is produced, transmitted and distributed. I mean, perhaps people do know that it is generated at a plant, "stepped up" to a very high voltage and at the receiving substations "stepped down" and then distributed at even a lower voltage. But is that all that is involved? Most readers of my blog are engineers or people with scientific background. I wonder how many of us can actually go beyond this simplistic explanation.

So, if I may, I will take the liberty of explaining to you how electricity is "dispatched" by a collection of generators to a collection of loads both of varying qualities (in terms of their electrical, mechanical and economical behavior). So, let us think of geographical area with some mix of generating stations and load centers (like cities and industrial areas). A good understanding of how, so called, "economic dispatch" works is very essential in making technical, political and policy decisions.

Some points that we should consider here,
1. Energy is always conserved, so, the total energy generation at any instant is equal to the total consumption plus the losses.
2. The large scale power systems do not have any power storage capability, (except for large series and shunt capacitors for reactive power support and "shortening the effective length" the transmission line).

So, how is a typical day of a power system look like? see figure 1.

Figure 1. Demand response showing projected load versus actual.
Image from Energy Information Administration (EIA) office of the Department of Energy, USA

If you have not been able to see it in the picture above, there is a fore-casted demand curve and an actual demand curve which is satisfied in real-time. The important point here is that, a large part of this demand is satisfied by the big plants and is called the "base load". Big coal, gas and nuclear plants are often in this category. The other, more rapid changes are satisfied with generators that we generally do not associate with power systems; these are fast, responsive generators such as gas fired, jet, diesel generators. Now, if you think about it, it is very economical to have large constantly working coal and nuclear power plants than to have sparingly working, expensive fuel gas turbines! How best to use the available generators and plants and transmission lines is the problem of economic dispatch or often called the "Unit Commitment Problem". If it interests you, these are linear programing problems!

Anyway, now that we know that nuclear plants actually work for days with some "operating reserve", may be it is a good business decision to commission and operate more of them. For they do not emit CO_2 or other green house gases, except water vapor! BTW if you did not know, water vapor is a greenhouse gas! and has a positive feedback kind of effect on the environment (google that!). I would bet that water vapor is equal to if not any worse than effects of CO_2 emissions, may be its is time to pay for "water credits".

So, guess, we now know two factors in power systems.
1. being able to satisfy the base load in the most economical manner
2. Lower green house gas emissions.

If you did not think of it,
3. Fuel is a big factor. I am sitting here in Wyoming, one of the largest source of coal in USA besides of course snow and wind! Wyoming is one of the few debt free states in USA!
4. Safety and Security!
It is said that the biggest worry of developing countries with nuclear energy is their historical show of lack of safety discipline! We Indians know ourselves how we work! "Chalthi ka na gadi"

Are there any other factors, can you think of some and comment?

Will continue this later this week.



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