Energy Mutations From Raw Source to Consumer Usable

 

Energy Mutations

From Raw Source to Consumer Usable

Preface: Work is manifestation of energy. Energy is a basic need for any activity. There is no change in status of any object without application of force produced by energy.  Everything is standstill without energy due to inertia. Even all the creatures on the earth are alive till all their essential organs like mind, lungs, kidneys, intestines, gland etc are regularly functioning. And energy is required for functioning of these organs. Therefore creator has provided energy source within the body. Carbon is taken as food in the form of carbohydrate and oxygen in air while breathing. Energy required by each organ is produced locally by metabolic process. This is example of natural distributed generation of energy. This biological energy is primarily used for internal functions as above. This energy is also useful for external essential activity like movement for water, food and shelter for protection and peaceful rest. Spare energy is used for play and pleasure. This is almost common for all livings on earth. But humans have additional gift of fully developed mind. So they apply their intelligence to use spare energy for others purpose in their favor. They developed various tricks for ease in their essential activities. Such tricks made their task easy and fast. So they developed more and more devices for such convenience. So they were eager for such facilities. Also some of the devices made life comfortable. So they liked such luxurious life. This followed endless efforts for more and more facility and luxury.

All such tricks-devices-machines require energy to operate it. In some cases human capacity found insufficient for the purpose. So they resorted to joint efforts and succeed to achieve the goal. Their intelligence suggested use of animal power. So they employed horse, bullock, camel etc depending on requirement of power and availability of animal. Letter on observed power of solar radiation useful for heat and light. Solar heat proved protective against cold. This may be the first lifeless energy source introduced to human. Accidental fire in forest introduced other source of light and heat. Fire found useful for making the prey soft for eating with better test. Fire was also protective from cold, darkness and wild animals. They understood wood (dry tree) as source of fire and also found out how to get fire.

Natural Sources: As discussed earlier, there is provision for energy within body for essential functions to be alive. Similarly there is provision of energy sources on earth itself. Energy packs in various forms are available in nature at sub-terrain, sea and sky.  We just identify and develop trick to get the energy.

Never ending chase for energy continued and is still ON. Numbers of energy sources in different forms were identified at different times at different places. Primary adoption such energy source was to utilize it in the raw form where and when available. Energy in solar radiation is available in open space during the day time as heat and light. So it was utilized for that purpose only. Hence there were limitations for utilization of natural energy.

Raw energy available in sources deviates in following three aspects that impose restriction on utilization.

Energy may be available in the form other than usable

Energy may be available at the place other than where needed

Energy may be  available at the time other than when required

Therefore raw energy requires processing as under to match the needs.

Transform: Available energy is transform to usable form. So some device is used to change the form of energy. Requirement may be single or multiple conversions to get usable form. Each conversion requires appropriate device. Energy in chemical form of fossil fuel can not be used as it is but useful when transform to heat by burning.

Transport: Energy is required to transfer from the place of availability to the place where it can be utilized. Appropriate device has to be used for transfer of energy. Transfer of energy may be feasible and convenient in specific forms.  When original form of energy is not suitable for transport, it may require to transform to suitable form for transport. In such case devices are required for transform as well transport. Natural gas is taken to the place of utilization.

Time shift: Time shift is required when energy is available but can not be used at that time. So it requires temporary storage of energy till the time when it can be used. Again feasibility of storing depends on the form of energy. In case of the energy form is not suitable for storing, it requires to transform in convenient form to store. In this case device is required for transform in addition to device for temporary storing and retrieval when required. In case of pumped storage system spare electrical energy is stored as potential energy and again converted to electrical energy when needed.

All together possibility is need of multiple devices to transform raw energy in the suitable form for use, transfer and storage. Devices also required for storage, retrieval and transfer when so required. Some time transform from particular form to desired for is not feasible. So needs first transform to intermediate form and than to desired form.

Net energy is reduced through devices due to anyone or more of the followings

Rejection: Rejection is part of the energy fed to the device is not converted as desired. It remain as if and leave as waste. Heat in condensate of condenser.

Leakage: Leakage is the part of energy diverting from the process to waste. Liquid and gas leaking from joints and control devices, heat lost to atmosphere from steam and hot water line, electricity lost as dielectric loss.

Device Use: Energy required for functioning of device. Energy consumed in motor for forcing magnetic field through core, current through conductor and mechanical force to overcome friction in movement.

General Device Layout

Ultimately results is poor gain from available energy source. Therefore it is desirable to manage with minimum devices for conversion, transportation and storing.

Following measures may be useful.

Use natural (raw) form of energy where possible: Lighting requirement during day time can be accomplish by using daylight.

Heat of the sunray can be used for hating and drying purpose as in solar water heaters, solar cookers, and solar steam generators for industrial and large kitchen.

Natural breeze is better option instead of fan and air conditioner. Cross ventilation facilitates fresh air flow. This is more evident in upper floors of multi storey building where air is clean and cool.

Preference to local source: Transportation and probable conversion to suit transportation is avoided while using local energy source. Distributed generation is a right approach in the matter. In addition to wind and solar, use of agricultural and domestic waste has dual advantage.

Matching available and utilization time: Formation of energy grid facilitates the purpose. Energy sources available at different time of the day, week, year, season feeds to users at different times. Only net surplus / deficit is required to store, retrieve or transport.

Cascade Utilization: Energy should not go to waste till there is scope to utilize residue energy. Heating element is provided in air conditioning system of the car. On the other side heat of the engine is wasted in radiator. Coolant from engine may pass through AC system before going to radiator. Coolant can have bypass system when heating is not required.

Minimize steps for linking source to use: There may be many devices linking energy source to use, each wasting part of energy. So energy system should have minimum intermediates for best utilization of the source.

Review of multiple conversions while using natural gas for industrial heating via electricity.

Heat produce by burning gas in boiler is transferred to water but part of the heat is wasted in flue gas.

Energy gained by water in the form of heat and pressure is transfer to turbine but only part is converted speed and major part is wasted in condenser.

Generator produce electricity but part of it is wasted as auxiliary consumption.

Voltage is boosted in GT wherein energy is wasted as loss.

Power is transmitted on line to near user area wherein transmission loss occurs.

Distribution loss occurs while supplying electricity to consumer.

All above steps are avoided while using natural gas direct for producing heat for industrial.

So using electricity to produce bulk heat is most uneconomical.

Similar multiple conversion to be avoided.

Better alternative / efficient device: Most of the devices used now are traditional. With technological development, now it may be feasible to have innovative simple, short and efficient method or improvement in performance / efficiency in traditional methods. Adoption of these may improve overall gain.

All above toils of multiple conversion for matching energy form, time and place is do away with adoption of common intermediate versatile form of energy pool for supply and use.  

Electricity is appropriate intermediate form of energy due to followings. 

Most versatile form of energy.

Feasible to convert raw energy to electricity by befitting option.

Feasible to convert to usable format.

Feasible for quick transfer from place to place.

Wide spread grid network for anywhere anytime energy dump and draw.

Least energy wastage by rejection, leakage and self use.

Well developed control system for regulation.

State of art protective system for reliability.

Following five Natural Phenomenon available to transform other form of energy to electricity.

1.       Piezoelectric Effect: Pressure is converted to electricity. Widely used in Gas Lighter. Trial is going on for getting electricity from pedestrian walk. Still no scheme is developed for bulk power production.

2.      Electrochemical Effect: Electricity produced by chemical reaction. Popular use is in Dry Cell. Other major application is energy storage for various applications like vehicles, phones, toys etc. Bulk energy storage is also tried for grid and EV etc. But no scheme is yet developed for power production on large scale.

3.      Thermoelectric Effect: Temperature converted to electricity. Mostly used as in Thermo Couple used mostly in instrumentation as temperature sensor. No scheme yet available to developed power.

4.     Photoelectric Effect: Light is converted to electricity. Solar radiation is converted to electricity by photovoltaic cells. Recently there is fast development in power production by this method.

Other form of energy available from solar ray is heat. This heat is absorbed and utilized for various purposes like cooking, drying, steam generation for cooking, industrial applications and produce electricity by conventional method.

5.      Electromagnetic Effect: Interaction of magnetic flux with conductor produces electricity. Electricity produced due change in magnetic flux linked to conductor is electromagnetic inductions. This is the most used principle for production of bulk electricity. Steam turbine, gas turbine, hydro turbine, wind turbine / mill or any system that has rotary motion uses this method to produce electricity.

Following three is basic requirement to produce electricity by electromagnetic induction.

1         Magnetic flux produced by permanent magnet or electro magnet.

2        Conductor coil linked within magnetic field

3        Continuous change of magnetic flux linked to coil.

Magnetic field of permanent magnet is limited and so the electricity produced using permanent magnet is also limited. So is useful for small power applications.

Mostly electromagnets are used for producing magnetic field.

Change in flux linkage is accomplished in three ways.

1.       Magnetic poles are stationary and conductor coils are moving: Conductor coils are used instead of single piece of conductor to multiply the induction effect. Coils are laid in armature (rotor) such that its sides cross opposite poles at the same time. Magnetic poles are stationary on stator. Electricity is induced in the coils on armature by electromagnetic induction when rotor is moved by prime mover due to changing flux linkage to coils. Electricity produced on armature is picked up by brushes commutator. This is DC generating system.

2.      Conductor coil is stationary and magnetic poles are moving: DC supply is fed to rotor through slip rings to produce electro magnets on rotor. Coils are stationary on stator. Electricity is induced in stationary coils by electromagnetic induction when rotor is moved by prime mover due to changing flux linkage. This is AC generating system.

3.      Electromagnet and conductor coils are stationary: In transformer primary and secondary windings are stationary. Primary is producing magnetic flux in core. Secondary is on the same core linked with flux produced by primary. Magnetic flux is produced by DC (unidirectional current) in case of AC and DC generators. Transformer cannot work when DC is supplied to primary because there is magnetic flux linked to secondary but is fixed. But magnetic flux produced by primary is changing when AC is supplied to primary. Now secondary is on the same core linked with changing flux. So electricity is produced in secondary.

There are many energy sources in various forms. Some of them are already in use since long whereas some sources are employed recently and still efforts are ON to find ways and means to harvest energy from few identified sources. Possibility is that new sources having potential for energy are identified in future.

Characteristics of various raw energy sources.

Availability over the day (Day/Night)

Availability over the year (Season)

Regularity (Predictable)

Storage scope (Dormant / Use or Let go )

Ease of transfer.

Convenience of handling

Reliability

Recurrence (renewal) cycle

Analyses of few known energy sources on above line.

Fossil Fuels: This is available under the ground in the solid form as coal and lignite, in liquid form as crude and in gaseous as natural gas and petroleum gas. Various derivatives of crude like petrol, diesel, kerosene, naphtha and residual RFO are obtained to suit different application. All these are chemical energy sources as they release energy in the form of heat by exothermic reaction with atmospheric oxygen. These are dormant source, naturally stored and remain available till explored. One after other such sources were available and used in the past. There was no idea for exhaust. These were used mainly in power plant to produce electricity, in transport as fuel and to produce heat for industrial and domestic purpose. It was in used since long and hence referred as convectional source of energy. It has major drawback that produce carbon dioxide and flying ash polluting environment. But now advance technique made it possible to estimate total stock of such sources on earth. This revealed limitation of stock and alarmed for future energy crises. This gave rise to concept of energy conservation and judicious use.

Coal and lignite is solid fuel used in boiler to produce steam and run steam turbine generator to get electricity. Rise / drop of generation is slow as numbers of auxiliary has to follow. Frequent start stop is not economical not suitable for thermal stresses.

Gas is either used in boiler for electricity as above else gas turbine is operated by burning gas in combustion chamber. Heat energy left in exhaust gas is used in heat recovery steam generator to produce steam and run steam turbine generator. Close cycle plant has limitation for start / stop but open cycle can be regulated as required. 

Oil is used in boiler for electricity as above or used in oil engines to generate electricity or use rotary motion in industries and transport etc. No restriction for start / stop.

Hydro Energy: Basically hydro energy is available in two forms - potential and kinetic.

High Head: River with regular flow may have drop (fall) on pathway way due to uneven land. Potential energy of water at upper level is used to run water turbine and produce electricity. Small natural or artificial reservoir developed at upper side receives and stores water. This facilitates short term regulation of generation.

There is limitation on use of potential energy. Head pressure at bottom of penstock and turbine will be unmanageable when level difference is very high. Such very high head is utilized by cascade stations. Part from the total available head is utilized in top stage. Second stage station just bellow intake is discharge of upper stage and so on.

Low Head: River flowing on moderate gradient and having continuous heavy flow is good source of kinetic energy. Here situation is use or loose condition. Low head water turbine is used for production of electricity. There is no scope for storing and regulating generation. Reducing generation means wasting energy. So this can be base load generation.  

Dam site: River having very wide catchment area has heavy flow during monsoon. But availability is only for few months only. So it is not economically viable to have power plant of huge capacity due to very low load factor. But storing water in dam at suitable location enables regulation of generation and fully utilization of available energy. Dam has still more benefit of water for agricultural, industrial and population. Generation regulation is technically feasible but requires coordinate with water requirement. Energy available is fixed based on storage capacity and seasonal inflow but is annually recuperating source and hence needs to be utilized before next cycle.

Pumped storage system is useful for short period energy storage to manage load variations over the day. Two reservoirs upper and lower are required. Water is pumped from lower reservoir to upper reservoir using surplus energy during light load period. Energy is thus stored in the form of potential energy of water. Energy is reproduced by normal hydro electric system using water from upper reservoir.

Hydro generation can be regulated in full range with start / stop also. Hydro generation is cheapest as only capital and operational cost is involved. So regulation of generation on run off river is uneconomical.

Wind Energy: Air in motion is wind has kinetic energy. It is available round the day and year but velocity of wind is unpredictable and uncertain. It is also use or waste type of source.

Wind Mill: Wind energy harvesting is by wind mill. Mostly high mast horizontal shaft wind turbines are used. This is expected to be cheap like hydro generation as no consumable input is required. But capital cost is yet high.

Other model like vertical shaft wind mill, wind mill tree etc are on trial.

Parachute Pull: Air trapped in parachute pulls the rope unwinding drum connected to generator through gear. After reaching definite distance, the parachute is tilted or top vent is opened to let air flow through and off load it. The unloaded parachute is drawn back up to fixed distance by winding drum run by motor. Energy generated by generator during pull by loaded parachute is much more than energy consumed by the motor during draw back unloaded parachute. Difference is net generation in each pull / back cycle. This may continue repeatedly.

Solar Energy: Solar radiation is unlimited sources of energy available anywhere but for part of the day except on cloudy days. It is a use or waste type source and unpredictable to some extent.

Solar energy is available in two ways.

    Insolation:. Photo Voltaic Cell directly converts solar insolation to electricity. It is static, light weight and almost maintenance free device. Continuous R&D made it cheaper and compatible with conventional electricity and widely used.

It requires wide area. So it was considered as suitable for waste land area only. But now better solutions are available. Covering road with sonar panel where no shadow of tree or building obstructing the sun rays has dual advantage of generate electricity and also prevent road heating. Similarly covering canals with solar panel and floating panels on pond prevents evaporation loss of water in addition to electricity. Installation has to be strong enough to secure during cyclonic weather.

Heat: Sun rays also produce heat where they hit. So it is used for drying and heating in various manners.

Solar cookers are mostly used for household application

Solar water heaters used for various purposes.

Solar steam generators are used in large kitchen, industrial and to produce electricity by conventional way.

Air in wide heat collector at bottom of Solar Chimney is heated by sun rays. Hot air is passed through chimney to set up air draft. Wind turbine generator set in the path of the draft produces electricity.

Sun ray heat can be absorbed in water of the Solar Pond. The surface of water is covered thin layer of oil to prevent heat loss due to evaporation. Heat absorbed by water is used for various purposes.

Atomic Energy: Tremendous energy in the form of heat is released during nuclear fission while atom split by neutron collision. This heat is used for producing steam and run turbine generator set to get electricity. Suitable material like uranium is available under the earth. It is processed to make it suitable for use in atomic reactor. Normally it is not operated in regulation mode for safety reasons.

Hydrogen Energy: Raw energy source is hydrogen gas. It can be obtained by electrolyses of water. Ample water available freely. So it may be cheaper but production, storage and handling cost is hurdle for economical viability. It is used in two ways.

Hydrogen Cell: Hydrogen cell converts it direct to electricity by chemical reaction.

Hydrogen Fuel: Hydrogen is used as fuel in IC engine. This mechanical energy is used to run vehicle or as prime mover to run generator to get electricity.

Biomass Energy: Raw energy source is waste like agricultural, industrial, municipal, animal manure, etc. These are either burn directly to produce heat to electricity by conventional way. Sometimes it is converted to bio-gas in gasifier or by bacterial decomposition and is used for electricity or other heating purpose. Some special crop is grown to get oil like bio diesel from jojoba. Sometimes it is converted to solid pellets to burn with other fuels. This is possible on small scale due to limitation of inputs.

Ocean Wave Energy: Ocean wave is continuous process and is use or loose type source. There are two types of wave movements and accordingly devices are design to trap the energy.

Up down movement: Floaters at fixed place on surface of water moves up and down with crest and trough passing under it. This movement is ultimately converted to electricity.

Travelling movement: Water wheel half submerged in water at fixed place rotates by push of travelling wave. This movement is ultimately converted to electricity.

Ocean Tidal Energy: Ocean water rise and fall at regularly over the day and month. Specially built tank at the bank of sea will get in water by spill over during tide. Water turbine is run by this water during ebb as water level of sea is lower than tank. Energy available is for short period.

In case of double tank set up, the first tank gets in water during tide period as above. During tide period when water in the first tank reach particular level, water turbine between first tank to second tank is operated to get electricity. So generation is possible during tide period also. During ebb period when water level difference between second tank and sea is sufficient, the turbine between second tanks to sea is operated and energy is available. This is impermanent source of energy.

Geothermal: Heat from the deep earth is utilized to get energy. Suitable liquid is injected through pipe in the deep bore on the earth. Bottom of pipe remains submerged in the liquid at bottom. This liquid is converted to vapor and come up through other pipe line to run turbine generator set to get electricity.

Ocean thermal: Surface water temperature is high compared to deep sea temperature. Liquid of low boiling point like ammonia is evaporated in heat exchanger using surface water. Vapor is used to run turbine generator set and exhaust is cooled down in heat exchanger using deep sea water.

Lightening: Lightening is also a source of energy. But tremendous energy is available only for very short period. Location, quantity and time when it is available is uncertain and unpredictable. Hence capturing it is very difficult. One option can be floating collector and converters in the sky can collect and convert to high frequency electromagnetic wave targeting to receiving station on earth.