Saturday, January 24, 2009

A Riddle of Energy Part 1



Girish Abhyankar

Phone: +91 9860547471

Concept of energy

Universe is made up of particles – molecules, atoms, ions, photons. Particles cause various forces resulting into their own motion. “Motion of particle” we call energy.

Human societies use motion of particles - kinetic energy - in following different forms.

All the molecules forming a body constrained to move in one velocity vector: we call mechanical energy. Velocity measured in meters per second.

Random movement (in fluids) and random vibrations of molecules /diffusion of electrons (in solids): we call thermal energy or heat. Temperature indicates velocity of the motion.

Motion of electric charges constrained to move through conductor from one pole to the other: we call electrical energy. Electric current (in Ampere) indicates velocity of motion.

Free or constrained motion of photons: we call radiant energy.

All forms of energies are simultaneously present in any matter. We name mechanical, electrical (both constrained forms), radiant and thermal (normally random and free forms but can be constrained partially) energy depending on which motion we put to use. (Piston of an engine moves, and is also hot, radiating and electrically charged. We use only the constrained movement of all the molecules that make the piston and call it a source of mechanical energy).

Quantity of kinetic energy is a function of mass/number of particles and their velocity.

If particles, due to their specific positions, are capacitated to release kinetic energy (by a trigger), we call it potential energy or stored energy.

Human societies use the following different forms of potential energy.

Gravitational energy is the positional (height) energy of a body with reference to a datum, used as mechanical energy when released.

Chemical energy is the energy stored in configured arrangement of atoms/ions, used as thermal/electrical energy when released.

Accumulation of electric charges in capacitors is the stored electrical energy, used again as electrical energy when released.

Energy possible to be released by fission or fusion of atomic nuclei is nuclear energy, used as thermal and radiant energy when released.

Energy to activate a trigger for release of stored or potential energy into kinetic energy is called activation energy.

Laws of energy, traditionally called laws of thermodynamics:-

First law or the law of conservation: The energy of the universe is constant.

Second law or the law of entropy: The entropy of the universe always increases [2].

Both the laws are fundamental and applicable universally.

Entropy: At any moment of time every particle occupies a unique position in the universe. (Since one particle is occupying a position there can not be any other particle in the same position at that moment of time.) Forces depend on positions. Since position of every particle is unique, every particle experiences unique forces acting on it and therefore, motion of every particle is also unique. It is highly improbable that motions of particles are identical in respect of their velocity vector. Completely irregular motions of particles, as per the Law of Statistical Behaviour [1], result in their dispersal.

Entropy is a measure of dispersal of particles.

In all physical processes molecules and energies associated with their motions and positions disperse [3] in the direction of increasing probability [1]. Entropy is a function of the number of different ways or microstates in which the energy of the molecules in a system can be arranged by positions and velocities. The number of accessible microstates for dispersal of energy depends on the constraints imposed by internal and external forces on the molecular motions. If the number of microstates accessible for dispersal of energy is small, due to constraints, entropy is low. If the number of microstates accessible for dispersal of energy is large, with no constraints, entropy is high [3].

Entropy is at the highest when the rate of dispersal of energy is infinitesimal i.e. the dispersal virtually stops - a state of equilibrium corresponding to maximum of probability [1] for local and temporal frame of reference.

Entropy is independent of the path of the process (technology) and medium (materials) and depends only on the endpoint condition i.e. volume and temperature [2].

The Law of Entropy: Any spontaneous changes in a physical system occur in the direction of increasing entropy [1]. Energy of any type will change from being localized to becoming dispersed or spread out -- in space, in quantum states ("energy levels") of microstates and thereby yield systems with greater numbers of microstates [3].

Thus in processes of energy transformation, storage or transportation energy output is always less than the energy input because energy disperses continuously - entropy increases - and the energy available for the intended final usage reduces 1) in such processes 2) with the time.

Decrease of entropy is reversal of dispersal - collection.

Principle of decreasing entropy: Entropy in one part of the system can be decreased if there is a compensating increase of entropy in its other part. The Law of Entropy requires only that the total entropy of the system increase and this can be arranged by making the second factor larger than the first.

Example: Some weight is placed on a shelf above the floor. According to the Law of Conservation of Energy, it is impossible that this weight will spontaneously and without any external help rise toward the ceiling. On the other hand it is possible to drop one (larger) part of this weight to the floor and use the energy thus released to raise another (smaller) part upward [1]. This trick is possible only if the weight is initially at a good height – possesses sufficient gravitational potential energy. If the weight is already near the floor, nothing can be raised upward.

Entropy can also be decreased by applying energy from outside the system under observation - weight lifted by a crane powered by an engine that runs by increasing entropy of coal or crude oil. But the energy stored as gravitational potential energy in the lifted weight is always less than the coal/crude oil energy spent in running the engine.

Decrease of entropy is a fall-out effect of increase of entropy somewhere in the universe. Energy for collection (decrease of entropy) is always more than the collected energy.

Observations in Nature

Since entropy of the universe is increasing, we observe, universe is expanding. Stars throw out matter and energy in space. New, smaller stars are formed out of the matter and energy released from breaking-up of larger bodies. Matter and energies tend towards uniform distribution in space, on earth: denudation of mountains, soil erosion, etc.

Solar radiation is due to entropy increasing on the sun. Solar radiation, as received on surface of the earth, is composed mainly of three frequency ranges. About half lies in infrared (IR) range, the other half is in visible range and some also lies in ultraviolet (UV) range. Intensity of solar radiation received on earth’s surface varies greatly throughout the day and the year. Since solar radiation reaching earth has no constraint, it is high entropy energy.

Frequency band of IR radiation generally matches natural frequency of many molecules over the surface of the earth and their random resonating vibration is the heating effect. Most of IR radiation is converted into heat.

The life on earth has to convert the only energy source on earth - solar radiant energy - into a suitable form required for survival and reproduction. Surface heating - random motion with no constraint, high entropy energy - creates conducive temperature and other conditions, winds, rains etc, but can not be converted into low entropy forms of energy such as mechanical or chemical energy, because decreasing entropy is impossible.

Plant kingdom is able to store the other half - visible light and UV – of radiant energy falling on it as chemical energy: complex bio-mass molecules by synthesising carbon dioxide, water and salts. Synthesis is decreasing entropy, possible by using huge amount of high entropy solar energy. Since energy necessary for collection of the same energy is more than the energy collected, plant kingdom remains stationery and collects whatever solar energy falls at their location. Plant kingdom grows very slowly because input solar energy is of low power. Plants spread themselves over larger surface area to receive maximum of solar radiation. They also use wind, rain and animal kingdom for their expanse to remote places, and grow wherever all inputs required by them are present.

For millions of years, photosynthesis has been the only method of decreasing entropy using solar radiant energy, not superseded by more efficient method by life on earth.

Animal kingdom on earth enjoys energy collected by plant kingdom in the form of biomass - food and raw material (low entropy energy). Animal kingdom maintains itself at a temperature higher than the ambient temperature by burning food and can, therefore, convert heat to mechanical energy for movement and to electrochemical form for data processing and communication, memory, etc as movement related functions. Input energy requirement of animal kingdom is large due to losses in energy conversions, heat radiation and friction met by consuming high energy density food readily available from the plant kingdom.

Animal kingdom survives by adopting itself such that it lives and reproduces on food generated energy, free natural services and not requiring any other external energy.

External Energy (other than food generated energy)

Human societies use external energy, besides food generated energy, for additional security - shelters and storages - , for comfortable living - tools and machines - and for enjoyment - toys and communication gadgetry.

Resource energy can seldom be used by human societies directly in the form it is available in nature. Energy transformation, storage and transportation are necessary so that the energy is made available at the desired place, at the desired time and in the desired energy form with the desired specifications - temperature/voltage. This involves decreasing entropy. This is possible only if the resource energy is low entropy energy and entropy of some part of this energy can be decreased during sudden increase of entropy.

Thus, only low entropy resource is of any physical benefit to human societies; high entropy resource, however large in quantity and available perennially, is not. Example: A tanker ship full of crude oil is a low entropy source because crude oil molecules are constrained inside the tank with fewer accessible microstates for dispersal. This resource is useful. But, if the crude oil spreads over the sea due to shipwreck, the crude oil molecules free, not constrained, with far more accessible microstates for dispersal, the entropy goes high, total energy remaining the same. Crude oil of increased entropy is useless for any benefit to the human society.

Decreasing the entropy has been possible by all kinds of heat engines (equipments) working on the above mentioned principle because the resource energy - coal and crude oil - is constrained in small volume and therefore, entropy is low. Ores found spread out in nature; at the lowest energy levels - the highest entropy - are collected, refined and then heat engines (equipments) are built using crude oil and coal energy. Building equipments is, thus, a process of decreasing entropy. Part of crude oil and coal energy used is deemed embodied in the energy conversion and support equipments to access, extract/collect, process, transport, install, store, activate, control, dispose the waste generated and also maintain both, the equipments and the environment affected. Embodied energy is the stored energy in positional/structural arrangement of molecules, manifested by saving in the process energy or facilitating energy transformation. However, embodied energy itself does not participate in the energy flow.

Examples of saving in the process energy: energy put-in to make a knife is deemed stored in the knife as embodied energy. Knife saves energy in the process of cutting. Vehicles, tools, machinery and explosives save process energy. Shelters save energy for protection. Processed food, medicines save internal body energy. Telecommunication equipments save data transportation energy.

Examples of facilitating energy transformation: Energy converters such as boiler, turbine, engine, cell, alternator, transformer, motor, pump, radiator, compressor, etc.

Storages such as battery and dam – facilitating energy/material storage;

Transmission lines, pipelines – facilitating energy/material transport.

According to the Law of Entropy, energy essentially disperses during conversions, storages and transportations. Embodied energy also disperses marked by continuous degradation of original properties of the equipments due to weakening of structural bonds - rusting, wear and tear, deformation, chemical changes, aging and eventual break-down, faster with the usage. Dispersed energy is lost, not preventable by any technology.

Using technology human societies accelerate entropy increase of a low entropy energy resource: coal/crude oil (entropy increase of coal/crude oil will otherwise continue at a very slow rate) by way of friction, radiation, scattering and scrap and achieve their purpose in the process.


Considerable technological effort is devoted to development of all imaginable energy sources besides coal and crude oil because coal and crude oil reserves are exhaustible and also, their inefficient usage is damaging the environment. Solar radiation, wind, nuclear, hydro (rain and tidal) and natural/biogas are harnessed for electricity generation. Farm produce is converted to high density fuels as alternative to petrol and diesel. Energy from solar, wind, nuclear, rain water, tidal, hydrogen, geothermal, bio-fuels, etc is claimed to be renewable/sustainable/inexhaustible and friendly to the environment. It is necessary to check the correctness of these claims in larger interest of the human society. Attempts to evaluate these claims by energy accounting methods do not lead to conclusion.

Evaluation of the claims

The claimed renew able/sustainable/inexhaustible resources are evaluated below for conversion to any low entropy or constrained energy, particularly electricity, a desired energy form because it can be converted to mechanical, thermal, chemical or radiant energy conveniently. Electrical energy is movement of electrical charges, constrained to move through conductors from one pole to the other with very limited accessible microstates for dispersal and hence electrical energy is very low entropy energy.

Wind energy: Air molecules and their kinetic energy (A) are free, unconstrained and therefore, wind energy is high entropy energy, not possible to convert to low entropy, mechanical or electrical energy.

It is not possible to build a windmill of embodied energy (B) using energy in the wind because, due to high entropy, usable energy in wind (A) is less than the energy necessary to make the windmill or (A) < (B). Coal and crude oil energy (F) is, therefore, used for making windmills.

Energy embodied in windmill is less than the energy used making the windmill (B) < (F). In a windmill system, output energy is less than the input energy,

(C) + (B) < (A) + (F) where total energy delivered by the windmill in its life time is (C).

Rearranging the above expression, (C) + (B) ─ (A) < (F).

(A) < (B) and, therefore, (B) ─ (A) is always positive.

Thus, (C) < (F) or total energy delivered by the windmill in its life time is always less than the coal and crude oil energy input making the windmill.

Rearranging again, (C) < (A) + (F) ─ (B).

Since (F) ─ (B) is always positive, (C) < (A).

But as (A) < (B), (C) < (B) or the total energy delivered by the windmill in its life time cannot provide energy to make another windmill of the same capacity.

Solar energy: Radiant energy (A) from the sun is unconstrained and, therefore, the entropy is high, not possible to convert to low entropy thermal or electrical energy. Solar radiation concentrator or photovoltaic cell is made using crude oil and coal energy (F). The total energy delivered by the concentrator or the photovoltaic cell in its life time 1) is always less than the coal and crude oil energy input making them 2) cannot provide energy to make another concentrator or photovoltaic cell of the same capacity.

Hydro energy: Kinetic energy of rain or tidal water molecules (A) is unconstrained and hence entropy is high, not possible to convert to low entropy electrical energy. Hydro power plant is made and operated using crude oil and coal energy (F). The total energy delivered by the hydro power plant in its life time 1) is always less than the coal and crude oil energy input making it 2) cannot provide energy to make another hydro power plant of the same capacity.

Nuclear energy: Isotope of uranium, U-235, is the only fissionable substance on earth, always found strongly diluted by the heavier unfissionable isotope U-238 (0.7% of U-235 and 99.3% of U-238), hindering the development of the progressive chain reaction in natural uranium. It is, in fact, only because of this dilution by the inactive isotope that the highly fissionable atoms of U-235 still exist in nature, since otherwise they would have been all destroyed long ago by a fast chain reaction among them [1]. Since energy dispersal from the nuclear energy raw material has virtually stopped; the resource is at equilibrium. The entropy is the highest and therefore, it is not an energy resource of any energy. Nuclear power plants are built and operated using coal and crude oil energy. The total energy delivered by the nuclear power plant in its life time 1) is always less than the coal and crude oil energy input making it 2) cannot provide energy to make another nuclear power plant of the same capacity.

Natural/Bio gas: Gaseous form energy resource is a high entropy resource because gas molecules bubble out are free, unconstrained with very large number of accessible microstates to disperse. (Molecules of crude oil in liquid form are constrained by strong bonding forced with few accessible microstates for dispersal and, therefore, entropy is low. Energy density of natural gas as available on surface of the earth (STP) is 39.6 kJ per liter as compared to crude oil 37300 kJ per liter.) It is impossible to harness natural gas energy without external help. Gas power plants are built and operated using coal and crude oil energy where natural gas is compressed to 250 bar pressure to 11160 kJ per liter or liquefied to 25780 kJ per liter (decreasing entropy) for use in automobiles as fuel equivalent to petrol - 34920 kJ/liter or diesel - 38520 kJ/liter.. The total energy delivered by the gas power plant in its life time 1) is always less than the coal and crude oil energy input making it 2) cannot provide energy to make another gas power plant of the same capacity.

Farm produce: Natural biomass, 7.5 tons/hector, crop standing 1 m tall, in 100 days is 11000 kJ per square meter or 110 J/liter/day is a highly spread-out energy resource equivalent to less than a drop of crude oil/day - high entropy. Making and operating equipments, providing other inputs required cultivating, collecting the farm produce from very large area and processing them to high density fuel is done using crude oil and coal energy. Energy cultivating, collecting and processing is more than the net energy available from the farm produce generated high density bio-fuels.

Human/animal generated mechanical energy from farm produced food as original source is also high entropy energy and, therefore, its conversion to low entropy electrical energy is not possible.

Hydrogen, geothermal, natural biomass, etc are also high entropy sources and provide no net energy benefits to the human societies. None of the energy sources is renew able or sustainable for current high energy density technology and life style.

As (F) is always greater than (C); harnessing high entropy resources uses crude oil and coal in larger quantity; depleting their reserves faster and damaging the environment even more than if crude oil and coal were used directly for the same purpose.

Evaluation methods

Evaluation of energy sources for their renew ability or sustainability by energy accounting method requires input energy data independent of exhaustible energy source. But, equipments for harnessing energy are necessarily made using exhaustible crude oil and coal energy as original source and therefore, energy accounting method is not applicable. Observing entropy of the resource energy is the only method of evaluation.

Our energy measuring system has to be and is unidirectional - in the direction of increasing entropy. We convert all energies in question to heat and compare. We convert solar radiant energy to heat and measure. We burn biomass and measure the heat released. We compare these two measurements and conclude that 100 kJ of solar radiant energy must have been necessary to make 1 kJ of biomass energy.

We can not measure in the direction of decreasing entropy. We can not experimentally measure how much solar radiant energy is converted to say 1 kJ of electrical energy. A photovoltaic cell is necessary for this conversion which is made using coal and crude oil energy as original source. We can not experimentally measure input solar radiant energy, energy for compression and thermal energy that go in making coal and crude oil used in making a photovoltaic cell. Thus overall efficiency of photovoltaic cell can not be estimated. Input/output method of evaluation is not applicable to non-biomass – solar, wind, nuclear, hydro, etc - energy sources.

Coal and crude oil is available for free in nature. We pay only for the human services involved in providing us derivatives of coal, crude oil or biomass energy. Original source energy is free. If the input energy is largely free evaluation of an energy source for sustainability, independent of coal and crude oil, by input/output method is misleading.


Solar, wind, rain water, tidal, hydrogen, geothermal and bio-fuels are not renewable/sustainable/inexhaustible energy sources and they with nuclear and natural gas are not friendlier to the environment than coal and crude oil. Machines and gadgetry converting these energy resources into any low entropy energy are perpetual machines of the second type and do not deliver any energy on the net basis.

Energy resources that are of low entropy on or very near the surface of the earth - coal and crude oil - are only useful for current high energy density technology and life style.

Corollary: Superconducting energy for net energy saving is impossible.


[1] George Gamow, One Two three...Infinity (Bantam Books, 1979) p. 200, 226-8, 186-7

[2] Feynman Leighton Sands, The Feynman Lectures on Physics Volume 1 (Narosa publishing House 1997) p. 566, 568

[3] Frank L. Lambert, Professor Emeritus Occidental College, Los Angeles, CA.



November 15, 2010

22 comments: said...


I need your feedback on the article. This article is about energy and I found this view radically different than the current trends in renewable energy. The article is based on main article 'Evaluation of Energy Sources'by Girish Abhyankar, a Pune based thinker, researcher and practitioner. People find the main article too technical sometimes and hence I have tried to made it bit easy in my article.

Your feedback will be of great help in finding out what to do next and how to propagate this thought.

Hoping to hear from you,

Mrinalinee Vanarase said...

Thanks for the articles. In the first place, I attended a workshop in 1974 at Goddard College in Vermont, USA, on organic agriculture, alternative energy and eco-friendly anarchism. One of the lecturers made approximately the same point which I think you are making.

I am not convinced, however, that the energy input in manufacturing alternative technology will always be greater than the input.

If monetary cost and savings can be used as a measure of energy input and output, then I think there are some strong arguments against your thesis. Here in Israel solar water heaters are very popular because the cost of the solar collecting panels, the tank, the pipes and the installation is covered within a year or two by the reduced cost of electricity. If you have a solar water heater, then you will use electricity for heating water only when the days are very cloudy. And that is not very often in Israel, even in winter. And then after you have paid for the solar water heater you can use it for years with no added cost (if it is high quality).

I know that windmills both for electricity production and for direct operation of water pumps are very popular in the US plain states where they have very high winds. I don't think farmers would use them if they were not economical.

For many years I had a bicycle light powered by a dynamo which was turned by my front wheel. I could use the same dynamo-light set for many years, only having to replace the light bulb. Now it is hard to get them and I have to use a battery lamp and either change or recharge the batteries. I cannot believe that the dynamo set takes more energy input in production than it puts out. They really do last for years and years.

Maybe the scale of things is important. Maybe, but I am not sure even of this, a city-scale methane plant is energy inefficient. But can this really be said of the small, family scale methane plants which you and I have discussed and which I remember the State of Maharashtra was subsidizing?

As for city-scale plants, I have heard that they are used on a large scale in Sweden and that Volvo cars even run on their methane there. It might be possible to verify the energy input-output question on this by checking with the Swedish government.

As for hydro-electric power, maybe the input is greater than the output for huge dam projects. But in Scotland in the 1960s I saw very small hydroelectric systems run by small streams. I wonder if their input is really greater than their output.,

Besides scale two further considerations, location and durability, should be discussed. Solar power is very popular and I think very energy efficient in Israel where we have a great deal of sunshine. This might not be so in every part of the world, certainly -- to take another extreme -- not in Britain.

As for durability, if your device, whether it be a windmill, a solar hot water heater, or whatever, is very well made so that it will last for many years, then there will be more of a chance for output to catch up with and to pass input.

In short, I think that the matter is much more complex than you and Girish present it.

--Yeruham said...

Hi Mrinalinee,

I read the articles you had sent yesterday and its indeed a coincidence that I was actually thinking on the similar lines, though at a most elementary level, i.e what does it take to produce the non conventional energy sources and can the technology used to produce these alternate sources of energy ever be eco friendly.? What about the waste that is generated through these sources? Is that waste bio degradable waste and if not have we thought of how to manage that waste? While in Ladakh I could see the redundant solar panels contributing to the non degradable waste. That is one region where solar energy has been highly promoted and in a way become alternate source of energy in the true sense. In Sangli , some time back a farmer mentioned that land required to lay the solar panels to generate power to run simple water pump, to be around one acre( I don’t know if that is so) and then the rational behavior still would be to put the land under cultivation than use it for laying the solar panels. The other day my sister was boiling water using houshold trash for fire. When I questioned her about the pollution she is generating she asked me back " and what about the pollution created to extract and transport the LPG? Point!

I feel both the articles are questioning the liberal and neo liberal arguments that markets will do the efficient allocation of resources and that the technology will diffuse the limits to growth. The proponents of alternative energy sources belong to the school that technology is answer to all the environmental issues. So this school would never question the side effects of the technology. Till date no technology has ever been full proof. While it has given solution to one problem it has created ten other problems that need some other technological solution and thus proliferates the chain of so called researchers, designers and demi scientists who bring in a car that runs on battery but do not tell us how that battery is produced and if all that gets into the battery is eco friendly. So I feel to understand the concept of entropy is important.

You have quoted the example of butter milk to explain the concept of entropy. I would like to take it a little further and question the rational behind the production of so called environmental films we have been making. Every NGO feels it important to make a film today. However no one is ready to question the environmental cost of making even a small film of five to ten minutes. Majority of the people don’t even get to see these films and they only remain well stacked in a shelf some organization. The budgets of some of the documentaries, the ones shot on simple video cameras is also quoted to be nothing less then five lakhs. However there are handful of films that have generated the required impact that such a film should create. Has there been any environmental movement instigated by a film? And we still call the medium to be powerful! I think in the name of technology we are only creating sophisticated clutter and are actually wasting our energy generating waste and then again on how to degenerate that waste.

After reading both the articles I feel that none of the articles have defined the message. I need to know why should I know the concept of entropy and where do you want to take me after understanding what entropy is. You have raised an important issue and the same needs to be debated however your article needs to be a bit more articulate. While the first article is heavy on jargon ( I guess its an academic paper and not meant for the lay person), your article bends towards over simplification and you wish to make the lay person understand the debate. Let us know what you are questioning through the concept of entropy and the direction of thought that we as readers with your help should be taking.

I wonder if I have understood the concern and the issue correctly or have drifted away from what you and Girish Abhyankar have to say.

Jyoti said...

Hi, again

I notice that Jyoti Patil sent his reply to your entire distribution list. Should I also do that?

Also, in addition to what I sent you I have a few further comments. But I won't do anything until I hear back from you.

I think that is is an extremely important and interesting discussion. Whether we all agree is not important. It is part of the ideal of academic freedom that we learn from free discussion. The important thing is that the discussion take place and that we learn from one another.

Yeruham said...

the author clearly doesn't understand entropy and the second law of thermodynamics..
aburd to say that high entropy energy cannot be converted into low entropy energy - it is being done all the time. Human beings themselves are low entropy systems.

what the second law says is that the total entropy of the universe will increase because of windmills etc - fair enough. but who cares? are we trying to reverse the second law or something? it is even true that the total 'energy' available in the world will decrease because of windmills etc. but again why should we care? Re we trying to prevent the sun from burning out?
ashok said...

Thank you for raising a nice question but is there numbers somewhere, with a methodology, to suggest what is the embodied energy in each of these cases and the likely energy savings achieved.
For example can we start with a solar box cooker? What is the embodied energy in producing one and how much of an energy does it make/ save in its lifetime.?
Same thing with a solar panel.

One other point, seems to me that solar energy incident on the earth on a daily basis seems to be the only additional energy available to us on earth. The rest add significant negative dividend in terms of loss and entropy. Is that right?
In which case the entitlement of energy for the earth as a whole which is sustainable , is the energy available from the sun ( which also includes the tides that are created nd the winds that flow) . Is that right?

Sometimes the basics are the most problematic for a simpleton like me .

Finally I like both the papers , since the job of a paper is not to be God's truth but to start discussion and improve understanding of our world. One paper targets a more scientifically erudite audience and another a more simpler audience.

Vishwanath said...

The subject of embodied energy has been well studied - starting with the systems ecologist Howard T. Odum. Google his name and you will find lots of material and many applications from him the extensive hierarchy of students that have emerged from his teachings.
There has been a lot of discussion on the blogs recently on net energy analysis. You probably can find a number of links to it at especially from Charles Hall.
Not easy to apply, but the system itself is not simple. Pretty cool stuff... this emergy!
Hope that helps.

Nitin Pandit said...

Dear Mrinalinee and Girish,
Nice to see a technical write-up as well as an abstract for lay-man written by both of you. After seeing the responce and the list of people in Cc,I couldn't help myself from writing my comments.
First of all, let me agree that the best way to tackle the Energy issue (and for that matter to tackle environmental, mental, physical (obesity!) and monetory issues) is to REDUCE CONSUMPTION and DECREASE NEEDS.
Having said that, I have a confronting view on the logic of using Entropy to prove that the altenative energy resources being considered today and not of practicle use. Please see the attachment for my comments.
I would like to confront with Jyoti too, rather her views on Technology. I think Technology development is a never ending process. Like Jyoti pointed out, one technogoly solves a problem but creates 10 new. My point is, the same sword of Knowledge and Technology can be used to tackle those 10 new problems. However, the best way is to reduce consumption to a minimum so that the number of requirements and problems would be reduced to Nil .... but that is a hypothetical situation. So we would need Technology and Knowledge base to live together as a Society. Judicious use of technology reaps lot of benefits in terms of health, safety, longivity and conmfirt. Also, Jyoti's questioning of Ecological films is also out of place, the amount of environmental damage done by a good thought provoking film is far too less for the awarness it brings.
Winding up for now. Due to large number of mail addresses, I doubt whether this mail would reach to all in the Cc list.

Yogesh Borole said...

may i try to understand your position in bits? through small steps?
Could you explain, why do you say energy harnessed from the wind will be always less than that required to construct the wind mills?
Unlike nuclear fuel ,only small part of wind energy can be converted into high grade (mechanical or electrical) energy . Agreed. But here we are talking about efficiency And when we talk about the total energy required to create wind energy converters there is no need to bring in efficiency.Just because a source such as wind has low grade energy (due to high entropy) it does not mean that the total quantity of high grade energy it will yield will be less than that required for constructing (manufacturing and installing) the wind mill.
May be i have not grasped your point and missing something obvious...
pardon me if i happen to respond late to your response to this.
thanks and look forward to your response,
milind said...

Dear Mrinalinee,
Thank you for including me-I am not at all knowledgeable in these things but did enjoy the discussions very much.I do realise that tapping wind and solar energy may lead to more questions of waste and recycling. And may not be the best use of resources. I do also agree that less consumption is a much better way to go
The point I would like to make is this:

Wind and solar energy can bring power to places which do not have electricity-like in the villages in Panvel where TCS Maitree volunteers are working.

Methane,natural Gas are also making life much easier for many villagers.

Is there an alternate way to do this(alternately!),please?
Cost of keeping so many people beyond the reach of alternate power should also be a consideration in all this argument.

Coming to the articles- yours is much simpler and easier to understand. The other article is more technical but interesting would need more effort for lay people. But reading both of them one after the other made a lot of sense!! From the simple to the complex...
Thank you
Warm Regards

Mala Ramadorai said...

Dear All,

Thank you very much for your response!!

We, Myself and Girish Abhyankar, are trying to write a consolidated reply to all the mails in couple of days. I am sure some people are still reading the articles and we will keep getting responses. But we will send our first cut for the mails we have received so far.

We are happy that the dialogue is started. The argument will now find its way through further debate and discussions. Those who are based in Pune- we can meet sometime for one to one discussion. That helps a lot in clarifying the doubts. For others, we will keep interacting on emails and will try and respond to all the queries.

Our ultimate interest is in defining appropriate action, and this debate will lead us to think on correct lines. As I Krishnamurty said, there are no immediate solutions to immediate problems! But knowing our predicament is perfectly is not a bad start.

Thank you

Mrinalinee and Girish said...

Mrunal & Girish,

Some quick comments after I have gone through both the papers:

1. There are certain oversimplifications in the way it is presented.

2. We should have certain suggestions over and above the message of reduced consumption – which is perfect anyway.

3. Would human powered machines be better?

4. If we can develop a quick list of available forms of energy and what application is can be put to use – that might be very useful. E.g – drying clothes using sun is a right application of solar energy and not really using a dryer or for that matter trying to generate electricity! Using wind energy for pumping water might be OK – but not so much for generating electricity. Etc…

5. How can we harness the power of plants and trees – which are also a sure source of energy for all of us through food and wood as well.

6. While I have understood the very basic argument, it will become clear only through debate.

Having said that, if we can develop a handbook of appropriate energy use and try to put that across, even while we start discussing this subject, it might go a long way…

These are just my perspectives….


Ajay said...

Dear Mrinal & Girish,

Sorry for the delay in reply.

A lot of replies have also come in, but i am writing my comments without having gone thru them, sorry again if there would be an overlap. Intend to go thru these replies also during the weekend considering the holiday series. Will surely add on if required later.

Good content to go thru (both the files - the technical & the simplified versions). My comments are as under -

1. Is it possible to quantify how much energy does it take to create a wind mill or a hydro-power station etc.(as comparative statement)? Then, how much energy would it reallly produce in its life time (average life being considered). Third - what would be the per capita electricity consumption in rural, semi-urban & urban areas. These 3 figures will help in establishing the co-relation between existing parameters.

2. Secondly, i would take a different stand while i 'recommend' or 'stay away' from any technology of producing energy. As per my views, instead of generalising, i would perhaps think of selective utilisation of technologies in relevant geographical locations. Let me simplify - today you are generating electricity about a 500 km place away, then feeding in a grid, (bearing T & D losses which may be as high as lets 30% or 40% in some cases also, though i hope these figures should be to the tune of 20% considering the seperation of companies as - generation, transmission & distribution - so, ideally, accounting by now should be much better) & then using it at a remote location. In such cases, while you generate 100 units, at a larger scenario, your net usage might be ablut 60 - 70. So, all farther locations with relatively lower energy requirements can ideally be made self-sustaining by making them depend upon any of the non-conventional sources depending upon their geographical characteristics. Anyways, today, rural India bears a large electricity cuts. So, why not make them independant? (Generation & Consumption - at the source)

3. I would say this because nothing is so positive or negative in use - there are always 2 sides of the coin. It would be on our skill how to use what & in what % to reach our goals & also be sustainable. Thats a matter of planning & policy formulation. Applying a same formula all over might be easy, but not the best choice.

4. Of course, all this should be done while we are also reducing our wants parallely, use what is minimum required (necessity v/s luxury).

In case you need any clarifications on the above stated thoughts, please do let me know.

Pavaman Jainapur said...

Hi Mrinal,

Anthropogenic use of energy has always been over and above the expenditure of energy in stabilizing the energy systems of the universe, for instance lightning causing fire, fire destroying vegetation, energy expended to regenerate vegetation and so on. There is the law which says that whenever there is a change in the state or form of matter or energy, there is a loss, therefore the source that undergoes the least change would be the most efficient. However, anthropogenic use of energy in today's world, which has acquired complex dimensions can only, be met thru modification or harnessing of energy sources which require equipment to do so. Therefore, there will always be a cost attached to the anthropogenic use of energy in both ecological as well as energy terms. There is no getting away from it.

The only options therefore available are perhaps:

Reduce energy needs.

Design and manufacture the most energy and ecologically efficient systems for production of energy.

There will be many parameters to evaluate the energy and ecological efficiency of systems and for each of the systems a life cycle analysis from cradle to grave would need to be done to identify the most efficient system vis a vis the form, quality and the quantum of energy required by humans for their needs. We may always have to be prepared for the fact that the most efficient systems may not meet the parameters of human needs. But any system that reduces the ecological and energy burden which would perhaps be the measure of the cost of production would then be in the interests of mankind and his environment and as such alternative systems of energy need to be explored for future use.

Just for information and referring to Jyoti’s mail, the thumb rule requirements of solar power for electricity is 1W of solar panel for 5W of electrical power for 1 hour, 1W of electrical power would light up 10 sq. ft. of area using LED lights which would cost Rs. 250/- per watt of which Rs. 165/- would be the cost of the solar panel.

For solar heating 1 sq. ft. of solar panel is required to heat 4 gallons of water and costs roughly Rs. 115-125 per 1 liter of water.

This information was collected at the Renewable Energy India 2008 Expo, Pragati Maidan, New Delhi held in August 2008.

Best regards,

Jayesh said...

Could not resist placing before the group this solar energy use plan based on what a roof receives

This saves embodied energy in water by harvesting rainwater at roof level
use solar energy for lighting,cooking and water heating
Saves energy required for waste water treatment
use solar energy to grow food

My idea of energy management which is decentralised
Vishwanath said...


Not really related, but here’s the link to the Ministry of Non-Conventional and Renewable Energy’s newsletter.

Does Girish’s paper take into account the energy generated from non-conventional over their entire lifetime, and is this less than the energy needed to make them. Just another riddle. Is there any way to calculate the energy balance implicit in windmills, dams, thermal power plants, nuclear power plants, tidal power plants, solar power, oil, natural gas, wood, paper, straw/farm residue….

We need to conserve. One way is to use less. Another is to produce and use at the same place. I don’t think anybody is ready to give up our energy-intensive lifestyles but we do need to rationalize them – be sensible, use muscle power when possible, to open doors for example. Or to walk to shops. First we consume energy to become fat, then we consume energy in gyms to become thin!


Nitya Jacob said...

My own apologies for a late comment. In comparing renewable energies versus fossil fuels, the absolute amount of energy used to produce the energy we need is one issue, which all the comments have addressed. I have no strong opinions as I do not know the figures when the life cycle energy balance of renewable v fossil fuel energy is compared. Not only will different renewables have different net benefits/costs, but different fossil fuels will also have different costs and benefits. Oil produced from shale or tar sands, for example, is extremely energy intensive in its production.

However, perhaps the more important consideration is the net production of green house gases from renewables versus fossil fuels on a life cycle accounting. Arguably, the renewables are producing much less greenhouse gas over their lifetimes than fossil fuels. This could be what makes the critical difference, especially if the more radical scientists are right and that in the next 100 years we face the risk of accelerated warming and climate shocks due to feedback effects in the climate system. If they are right, then the risks of continuing the use of fossil fuels are so enormous that we will soon be facing the equivalent of a wartime economy to reduce consumption and shift to low CO2 sources of fuel.

Barbara said...


We need to look at 2 aspects for renewable energy:

1. Are we already spending the energy and correspondingly have already emitted the greenhouse gases when making the corresponding equipment for renewable energy conversion aka windmills / solar panels and

2. Whether the conversion of higher entropy energy (less usable directly – like wind) to lower entropy energy (more usable – like electricity) is viable if we account for end to end energy (and not costs in terms of money) and all the losses we incur in energy conversion? This point is interesting and must be debated – even while availability of energy at remote places through renewable means can be separate social discussion.


Ajay said...

Dear Mrinalinee and All,

I was so much motivated after having discussions with Girishji on the
concepts of Energy, during our presentations at "Art of Living",
Bangalore last year on Energy. I congratulate both of them for
creating so much awareness and thinking.

I am a strong believer of Biomass - a major source of energy in the
future too. The fossil fuels and coal are different manifestations of
the same biomass, which are still the major source of energy on this
planet. The simple concept of sustainability is one to one+ or two
(atleast). I am focussed and working on energy from biomass. Designed
15 efficient good stoves including charcoal
producing stoves. Carbon sequestration using charcoal+ amendments for reclaiming degraded soils,
Improved technology for efficient charcoal production and crop residue

I strongly endorse Girish and Mrinalinee, and many other pioneers who
have contributed and still working in this field.

The growth of a plant is possible because of the basic rule that one
leaf is able to produce two or more leaves. A seed while in the
process of germination emerges with one or two leaves, these leaves
give raise to two or more leaves. This process expands from a sapling
stage to a fully grown tree. The leaf takes energy from the sun. Human
creations cannot match the nature. The total energy from a solar
photo-voltaic (PV) panel will not be able meet the energy requirements
to produce two or more solar PV panels. Therefore they are not
sustainable as much as any plant. The solar PV panel is a
manifestation of energy spent from other sources renewable /
non-renewable. The direct solar energy and the energy from biomass are
the two main sources of energy which would sustain life on this earth
in the future.

One of the group (yahoo) working with similar belief is

Jay the founder of the Groups says:

One thing I would like to dispel is the
notion of renewables. There is no such thing as a renewable.
Ultimately, some resources are lost no matter what. There may be
things that linger, and are more recalcitrant, but renewable is an

Solar and Wind are not renewable. The energy from solar and from wind
is available but not renewable. An oak tree is renewable. A horse is
renewable. They reproduce themselves.

But, and a very important but, the human made equipment used to
capture solar energy or wind energy is not renewable. In fact, there
is considerable fossil fuel energy embedded in this equipment. The
glazing on a solar collector of any kind – solar thermal water, solar
thermal air, and solar electric – requires energy to manufacture.

326 Members, Archives: Membership required
America was specifically designed by special interests (e.g., General
Motors, Firestone and Standard Oil) to require fossil fuel and
automobiles to survive. Peak oil will leave many millions of Americans
with no access to food or water and facing certain death. This group
mainly discusses what the evolved human brain "does". Besides "what
the brain does", we can also discuss (to a limited extent) "how the
brain works". Of most interest will be fitness strategies which
evolved to address the type ...(more)

Dr. N. Sai Bhaskar Reddy said...

What we all need, clearly, is good data on which to base our comparisons which can then help to decide what energy investments give the best return financially, environmentally and socially. Who has done the solid life cycle analysis of different energy sources?

barbara said...

Two papers that you sent make very interesting reading. First of all there is passionate analysis by Ms. Vanarase of the energy riddle in terms of the total energy needed to put renewable devises in action and what we get from that during its life time.It is nothing but ' Life Cycle Analysis ' ( LCA ) that is used in measuring the effectiveness of the system as compared to the resource used in its life.

While pedagogical form of the article is very appealing, we need to be careful . For example Switzerland produces 95% of its electricity from water. And surely it is possible to make renewable equipments from such energy without coal and oil. Unfortunately human being developed steel making that mostly uses coal but innovative potential of the human mind is so high that it is possible that we can make renewable energy without use of coal and oil.

In any case, it is not true that energy generated by wind mill is always less than energy used in its construction. You may like to see some articles where opposite is said


PV ( another case of RE)

Using traditional economics energy pay back time indicated in the literature is around 6 month for wind mill and two to three years for PV over 20 years operation. There are number of ifs and buts in that analysis, ( one of the most passionate 'buts' -and Ms Vanarase would love it-is : is present day economics of payback is really the right way to measure the payback or balance of energy?)

Coming to entropy, I must confess that this fundamental physics note rekindled my IIT-days debates on entropy and the universe! I had almost forgotten about entropy after coming to UNEP except that I always thanked God for making universe expand continuously to create more space to accommodate increasing entropy!!

Coming to the more serious response, am not sure about the utility of connecting entropy to energy riddle. The law of entropy applies to close systems. Therefore, in case of energy production / transformation on earth, you have to consider in first the system sun - earth, and its true that in this system, the global entropy will permanently increase, with the result of disappearance of the sun in some billion years.Thats all I can remark.

Finally, the riddle paper says that coal and oil are available to us free of cost. This I did not understand. We pay for that . But yes, we do not pay adequately because the economics that we use is traditional or even archaic. Thats why we have now to consider carbon tax and other cosmetic measures. Anmd thats why NGO deliberation on Green Economics is good start for the change.

Best Regards

Rajendra Shende,
Head OzonAction
United Nations Environment Programme said...

Dear All

In reply to your comments on our papers we, myself and Girish Abhyankar have prepared our common reply. Hope this satisfies most of your queries. We all thank you for your patient reading and appreciate your feedback. We also understand the limitations of email exchange. Not all the things can be explained in one article. May be someday we can make online presentation where you all can also participate and interact.

For now here is the reply-

Girish Abhyankar writes

A Common reply to points raised in e-discussion on the subject “Riddle of Energy”

1) Objective of my article is to scientifically prove that
Solar, wind, nuclear, hydro and bio-fuels are not renewable/sustainable/inexhaustible energy sources suitable for the life style based on current technology, needing high energy density inputs.
Using solar, wind, nuclear, hydro, bio-fuels and natural gas energy is, in fact, using coal and crude oil indirectly and inefficiently depleting the coal and crude oil reserves faster, damaging the environment even more than using coal and crude oil directly for the same purpose.
Energy resources that are of low entropy at ambient conditions on the surface of the earth are the only useful resources to the human societies - biomass energy alone. (Currently exploited coal and crude oil reserves near the surface of the earth and may be few more).

2) Funding, subsidies, incentives, tax rebates for using solar, wind, nuclear, hydro, bio-fuels and natural gas energy and expenditure on development, advertisement, promotion of the same and exploration of other high entropy resources is wasteful.
In the larger interest of the human society; funds and efforts for using local biomass, coal and crude oil directly or by minimum conversions to provide energy services will be more useful and meaningful. For example, illumination by LPG-mantle is far more efficient solution than by photovoltaic-battery-LED/CFL. Providing funds and efforts for LPG-mantle is a better idea. Research and development for direct efficient use of biomass energy with minimum embodied energy equipments needs to be undertaken. Fortunately many have realised this need and they are already working in the right direction.

3) Our energy measuring system has to be and is unidirectional - in the direction of increasing entropy. We convert all energies in question to heat and then compare. We convert solar radiant energy to heat and measure. We burn biomass and measure the heat released. We compare these two measurements and conclude that 100 kJ of solar radiant energy must have been necessary to make 1 kJ of biomass energy. But since we do not know how to decrease entropy - convert solar radiant energy to electrical energy - we can not experimentally measure how much solar radiant energy is necessary for, say 1 kJ of electrical energy. A photovoltaic cell is necessary for this conversion which is made using coal and crude oil energy as original source, available for free in nature. If the input energy is largely free; overall efficiency of photovoltaic cell can not be estimated. Thus input/output method of evaluation of non-biomass - wind, nuclear, hydro, etc - energy sources is not applicable.
We pay only for the human services involved in providing us derivatives of coal, crude oil or biomass energy (as and when we want them) but the original energy is free.

4) Costs reflect energy inputs and therefore, solar, wind, nuclear, hydro, bio-fuels and natural gas energy can not be economically viable. They operate with huge and continuous subsidy given in every country for years together by the local governments in hope that they will be self sufficient some day but this will never happen.
No institution or university in the world takes up such a viability study because the study will only reveal validity of the law of entropy.

Mrinalinee Vanarase writes-

Only to highlight above mentioned points-

• In the assessment of non-conventional energy sources, cost analysis and energy analysis are to be assessed separately. Many a times they are mixed and that doesn’t give us proper assessment.
• It is important to identify objectives of energy consumption before we raise the problems of generating electricity in remote areas and other such problems. This exercise leads us to far more creative and efficient ideas of energy generation and utilization. Many a times objectives are not defined or not defined in the light of holistic development and hence we adopt conventional solutions (i.e. solar, wind, biodiesel etc.)
• It is very well understood that coal and crude oil are not equally distributed and not available to every one in the same quantity and price. When we say that crude and coal are available for free, what we mean is their calorific value is available for free, what we pay for is the transport, storage and distribution of these resources. This is the reason why we should pay attention to the fact that renewable bizz is actually wasting available resources and money. Once we sweep away those options we are left with more equitable and responsible use of conventional energy. ‘Efficiency’ becomes important criterion in selection of technology.
• Our comfort and convenience is also to be understood in the light of ‘what human beings are made for (ergonomically) and what human beings are not made for. We as human beings also work as thermodynamic machines and exert energy in order to keep ourselves functioning. Why not to make use of this energy to make our lives more healthy comfortable and enjoyable!?

We very much agree that we now need to think on what is to be done next when we accept the first claim that socalled renewable is not renewable and not green. Various ‘Soft Technologies’ are to be discussed which are more efficient and satistfy the objectives of comfortable, enjoyable, safe life. Ofcourse, design and application of any particular soft technology is not a universal solution, it is to be adopted with reference to what you seek and where you are. The next discussion will be based on ‘Soft Technologies’.

Your comments are most welcome

Best regards

Girish and Mrinalinee