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Energy Conclave - 2006
N.Delhi28th July’ 2006
Dr.R.R.Sonde Executive Director (Energy Technologies)
NTPC Ltd
Frontiers in Technologies and Modernization
Electricity, the future form of energy
Frontier in Technologies & Modernization
Electricity is going to be the main stay of Energy
Transport sector could see a major change from natural liquid hydrocarbon to either Electricity, Hydrogen or Synthetic Liquid Fuel
Rural prosperity would see a major shift from the usage of non-commercial energy to electricity
050
100150200250300350400450500
1950 1960 1970 1980 1990 2000
Prim
ary
Ene
rgy
(mto
e/yr
)
Non Commr
Import
Wind
Nuclear
Hydro
Natural Gas
Oil
Lignite
Coal
Coal / Biomass and water would be physical form of fuel outside ‘fusion’
Solar is going to be the riding source of “energy”
Cheap Power : High Efficiency (from mine to delivery)
Abundant Power : Plentiful so that it powers the country’s growth
Clean Power : Environmentally Benign
All the available technologies are based of ‘Rankine Cycle’
However, for this to happen, electricity has to be affordable, available and clean
20
30
40
50
60
70
80
90
Sub-Critical
Super-Critical
CombCycle
PFBC IGCC
Eff
icie
ncy [
%]
We need to develop a ‘cycle’ which is fundamentally different.
It essentially uses ‘Condenser’ which limits the cycle efficiency to ~ 50%
Efficiency
Penalty for CCS (Carbon Capture & Seq) would be 10% points over and above the indicated efficiency figures
Frontier in Technologies & Modernization
0
20
40
60
80
100
COAL LIGNITE GAS PETROLEUM
Coal Reserve 250 billion tons
Gas Reserve 553 bcm
Petroleum Reserve 5.4 billion barrels
Abundant Power
Coal remains the most important fuel for power industry
The country has plentiful energy sources marked coal superabundance and weak hydrocarbons…
Coal is likely to become the source of Synthetic Fuel & Electricity required for Transp. Sector
Coal is expected to become the fulcrum of ‘Hydrogen Economy’
Frontier in Technologies & Modernization
Development of ‘Alternate Power Cycle’ has to be based on Coal being supplementedby bio mass, water and solar
I suggest two frontier technologies this country can take up in MISSION mode. They are
Clean Power
Producing clean power with coal, even today, is a challenge
Coal
ClimateTech
nology
Che
ap P
ower
Abundant P
ower
Clean Power
Hot Climate: Low Condenser Vacuum &
Boiler Eff No requirement of District
Heating
Very High Ash Content: 40% - 50%High Alfa Quartz ContentHigh Abrasive IndexLow Heating Value: 2500–3500 Kcal/Kg
The Challenge
Fuel extraction island
PowerIsland
[Turbine]Transmission
Combustion Island
[Boiler]
=85%-90% =65% =95%
Distribution [80%]
Frontier in Technologies & Modernization
=85-90% Overall <22%!!!
The Solution : The frontier technology - 1, India centric
Chemical Energy [Coal]
Electrical Energy
[Fuel Cell]
Gasification Island
[Gasifier]
~95% ~80%
Cycle Efficiency [65% - 80%]
Migrate from ‘Rankine’ based power to a fundamentally new one (Hybridise Rankine at back end using ammonia cycle)
Frontier in Technologies & Modernization
Unconverted Fuel Separator
Gasifier Hot Gas Cleanup
Gasification Island
Coal
Bio mass
Steam
Absorber
CoolingCombustion IslandZeolite
Electricity
Syn. Gas
Syn. Liquid Hydrocarbon
Ammonia / Urea / Chemical
Hydrogen
Fuel Cell
Char comb. island
CO2CCS
MALAE Cycle,
Low gr. Q
Bubbling bed
The Traditional Power Generation cycle
Input Energy = 100 Output energy =33
How to Increase the Efficiency of this system ?
14000C 5200C
Chemical Energy in Coal
Mechanical Energy in
Turbine
Electrical Energy
in Generator
Thermal Energy
in Boiler
Governed by 2nd Law of Thermodynamics
Fuel cell(Gibbs FE)
Carnot Engine(Energy)
Frontier Technology & Modernization
Why fuel cells?• Almost all conventional technologies use combustion and Carnot cycle• In this, the maximum theoretically achievable efficiency depends on heat source and
sink temperature• Though higher efficiency up to 83.7 % is possible, actual achievable efficiency is
limited by non-availability of suitable materials for such high temperature
Fuel cells are electrochemical devices that convert the chemical energy of a reaction directly into electrical energy.
Frontier Technology & Modernization
Frontier technology-2, Solar To Fuel And Electricity
Interfacing biology with physical sciences at nano-scale will be what ultimately will provide an abundant and perpetual source of fuel and power – perhaps at par with fusion. Fusion mimics solar while this would mimic nature (photo synthesis)
Frontier in Technologies & Modernization
Chemical Energy [Coal]
Electrical Energy
[Fuel Cell]
Gasification Island
[Boiler]
•Water•Bio Mass
Artificial Photo Synthesis
•Hydrogen•Methanol•Syn Gas•Electricity
Water / CO2
Bio Mass
Fuel So
lar
Ph
oto
n
Bac
teri
a
Artificial Photosynthesis
Hydrogen Methanol
Syn Gas
Products
Electricity
Alt. Fuel
Use
Elements in Solar to Fuel & Electricity
Powered by sunlight, nano scale inorganic materials
embedded in organic base convert water, CO2 to hydrogen, methanol
Using technique of synthetic biology, yeast can manufacture fuels
from bio mass
Polymers made from customised
dendmimrimers mimic photosynthesis
Frontier in Technologies & Modernization
What is different than already known?
1. Low temperature water (& CO2) splitting – to produce hydrogen or methanol
2. Low temperature conversion of cellulose (bio mass) into synthesis gas – Substitute for high temperature gasification process
I suggest following
1. Set up a 25 Mw (equivalent) FT-1 Mission. About six top institutions and two R&D savvy industry. Government to mentor the mission
2. Set up National Mission on Solar to Fuel Mission (FT-2). Would require interface with Nano, Synthetic biology and electrochemistry as backbone. Engg. Science to be introduced later
Frontier in Technologies & Modernization
Way forward:
At a later stage FT-2 will be dovetailed with FT-1
Time frame, Budget, Institutional mechanisms ???
While I have suggested two frontier technologies, the existing technologies seek intervention of good number of
technological solutions. Today we have adequate tools (scientific), knowledge, operating experience to develop the
intervention technologies.
May I suggest we take up one more new development of solar through heliostats? What is this
Frontier in Technologies & Modernization
Solar Tower
Frontier in Technologies & Modernization
Solar Tower
• A field of flat mirrors concentrate light on central receivers
• As flat mirrors can have two-axis solar tracking, high collection efficiency (>80%)
• An HTF (molten salts) is heated up (550 Deg C)
• Generate steam in a heat exchanger (535 Deg C)
• Run a steam cycle – Overall efficiency : about 24%
input fromcondenser
output to turbine
steam generator
hot storage
cold storage
565 °C290 °C
Salt Cycle
Cont. supply
Frontier in Technologies & Modernization
“When you really want something to happen, the whole universe conspires to help you to achieve your dreams”
…….. The Alchemist
by Paulo Coelho
CONCLUSION
Photo-Electrochemical Hydrogen
• Combine Electrolysis an PV technology into a one step process
• Problems: Chemical photo-corrosion and high cost
Cat
hod
e
Ph
otoa
node hv
2H+ + 2e- H2
V
RH2O + 2 h+ 2H+ + 0.5O2
Na2SO4
H-
e-
OxidationCatalyst
Reduction Catalyst
H2O H2S+
S2H+
2H+
0.5 O2Sun
hv
Photochemical Hydrogen
• Reactions occur at individual molecules suspended the solution
• A Photo-Synthesizer works in conjunction with a relay compound to transfer energy and generate hydrogen