Smart Grids for India Oct11

SMART-GRID IN INDIAN CONTEXTAshok Jhunjhunwala, IIT [email protected]

18/04/23 ICT Empowered Grid 1

INDIAN CONTEXT


As India’s Economy continues to grow

• India’s average GDP growth during 2006-09: 8.6%• Yet per capita income dismally low at Rs 46,500 last year• 7% world’s GDP: economy fourth-largest in world in PPP terms

• Increasing demand for energy from a low base• energy production just 4% of and consumption only 5% of world’s

• But affordability is the key• solutions that sell in india has to be at Indian prices

% of world

Population 17

GDP 7

Net national Income Growth 14.5

Personal Disposable Income 14.7

Consumption India World

per-capita electricity (kWh) 704 2752

average energy (TOE) 0.53 1.82

Euro1 = Rs65


India’s Fuel-wise Generation-Capacity (MW)

• Generation capacity continues to increase• Keeping pace with

country’s rapid (8 to 9%) economic growth


Dominant Fuel Sources• Coal: good for base-load

• significant domestic reserves• proven reserves of 105 billion tonnes• could last 200 years at current level of production

• Not good for environment

• Natural gas share up from 4.4% to 10% in last 15 years• emit half as much CO2 per kWh as compared to coal-based plants

• Hydroelectric potential of 600 billion kWh per annum• Capacity of 148.7 GW• only 23% realised so far• High initial costs and developmental risks

• Nuclear: small


Renewable Energy sources (RES)• High Potential: Achievements small

• perennial energy source• lower reliance on imported fossil fuels• lower CO2 emissions

• By 2012 to go up to 23,476 MW • Wind power to contribute 74%• Amongst five largest in world

• Constraint: High Initial Cost

Source Potential (MW) Achieved (MW)

Bio-mass 62,000 866

Wind-power 45,000 11,807

Small Hydro-power 15,000 2,735

Co-generation - Bagasse 5000 1334

Waste to energy 5000 65

Rural Distributed Power 30,000

405Captive Distributed: industrial / commercial

20,000

Total 182,000 17,222

Solar Power 4-7 kWh/sq m/day 10


Power Supply Shortage• Even Plant Load Factor have also

continued to increase along with generation

• Plant load factor still low• India’s Per-Capita yearly Electricity

Consumption is only 704.4 kWh as opposed to world average of 2,752 kWh

Availability far behind Requirements

• Meerut, barely 50 Kms form Delhi, has 12 hour power-cuts in summer months

• Most of 600000 villages connected• 17% villages unconnected

• Over 60% have power for 4 to 10 hours• Quite a few for less than 4 hours a day

Energy ( MU) Peak (MW)

Requirements 933741 136193

Availability 837374 118676

Surplus -96367 -17517

Surplus % -10.3% -12.9%


But average deficit is deceiving • As evident from the fluctuating

prices at Power Markets• Day variation of Rs 2000 to 4500

per MWh• Prices varies from Rs 2000 to

12000 per MWh in one week• Huge power shortage during

peak hours

Euro1 = Rs65


TOWARDS SOLUTIONSFor India’s energy problem


Transmission and Distribution Losses

• Varies between 20% to 45%• Average in between 30 to 35%

• Combination of leakage and losses• Requires technology and processes to plug this

• Transmission Losses are indeed measured in real time• Reasons for losses can be figured out

• Measure power at distribution transformer output line as well as the consumer-meters in real time?• An unusual difference implies something is wrong• Requires electronic meters with communications

• Indian homes uses mechanical meters: cost reasons


Yes, there is huge energy saving potential• Known technologies could result in huge electrical power savings• Constraints

• Low affordability in the nation• High Investment on new appliances, better processes• Today’s estimated saving potential: 183.5 billion kWh

Require newlow costsolutions

2007-08 Consumption (B kWh)

Conservative Savings

Agricultural Pumping 92.3 27.8

Commercial Buildings 9.9 2.0

Municipalities 12.5 2.9

Domestic 120.9 24.2

Industry (including SMEs) 265.4 18.6

Total (Billion kWh) 501 75.4


Why continue to use AC appliances? • Lighting

• LEDs, 10 to 100 times more efficient as compared to tungstenbulb, use only DC power

• CFL is neutral to AC or DC power• Motor: a small DC motor can be 2.5 tomes more energy efficient as

compared to a AC motor• Historically brush replacement needed – but not anymore

• A fan is primarily a motor – a dc fan also allows better speed control• A refrigerator is essentially a motor• An air-conditioner is primarily a motor• A washing-machine / grinder is a motor

• Electronics: all electronics (mobiles/TV/Computers) use low voltage DC• Need a ac/dc power adaptor to charge

• World switched to AC primarily for transmission of power• Any ac / dc conversion or vice-versa implies 7 to 15% losses

Has time come to switch back – at least at customer’s premises?


• India can certainly use solar energy, as capital goods prices fall• Solar photo-voltaic provides DC power for about six hours a day

• Rs 100 per Wh capital cost: with 10% interest and payback in 20 years, amounts to Rs 12 per year(not computing costs of land)• Costs a little over Rs 7.25 / kWh assuming 10% losses• As opposed to Rs 3 to 5 per kWh for grid power

• If not used immediately, would require feeding to grid• dc to ac conversion loss + grid T&D losses• Expensive energy being wasted

• Or Energy Storage Systems• Just like several other renewable energy solutions like wind-power, power from

ocean-waves

• Off-grid (local usage) in day-time would make a lot of sense

Sun shines brightly over India

Euro1 = Rs65

Solar PV power price computation

investment per kWh Rs. 1,00,000.00 sun-hours/day 6

interest rate 10% number of days /year 300

depreciation (years) 20 total power in Kwh gen/yr 1800

yearly payment Rs. -11,745.96 Losses 10%

price per kWh Rs. 7.25


• Batteries are expensive proposition for back-up• Lead acid battery: 1500 cycles if operated between 60 to 100% capacity

• 1 kWh back-up will cost Rs 16.3/ kWh assuming single charge / discharge per day• Assuming Rs 6000 per kWh battery and 10% interest rate

• Li Ion battery: 5000 cycles if operated between 10% to 90% capacity• 1 kWh back-up will cost Rs 20 per kWh assuming single charge per day

• Assuming Rs 25000 per kWh battery and 10% interest

• Solar requires different kind of storage• Storage price must work out to be small compared to solar generation• At current prices, it hardly makes sense

• Alternative: Can energy be stored in any other way• Say in form of ice and to be used for cooling• Current costs much less than that of electrical battery

Battery cost (per kWh) Rs. 6,000.00 Battery cost (to deliver 1kWh) Rs. 15,000.00discharge 40% depreciation (years) 4.11Number of cycles 1500 Storage cost per unit Rs. 16.27interest rate 10%cycles used per day 1Losses 10%

Lead acid battery

Energy StorageEuro1 = Rs65


When do the demand peak in India?• Depends on which time of year?• There are two peaks:

• Day: 11 am to 4 pm• Evening: 7 pm to 11 pm

• Evening peak is worst most of the year• Homes/ shops add to late office hrs

• Day peak can be bad in Summer months• Air Con is significant load

Sept 23rd

May 19th

Feb 9thJune 6thMay 2nd


Decentralized Solar PV• Would be ideal in day time

• To complement grid• Direct usage in offices / shopping malls can reduce the day time peak

load requirement to a considerable extent• Some coupling to ice-battery (charged during off-peak hours)• Makes economic sense today, provided there is space for solar PV

installation

• Some solar PV / solar thermal feeding to grid would be helpful

• What about evening peak loads?• Solar can not help here• Reducing load by enhancing efficiency• Reducing consumptions by introduction of time of day metering• Using some storage (electrical / ice-battery – charged during 5 PM to 7

PM)


SOME SCENARIOSreduce consumption of substantial quantities of diesel, kerosene, furnace oil


What are the options when power fail?

• Power-Sources:• Grid: Rs 5 per kWh: ram-bharose (as per god’s will)• Diesel generator: Rs 17 per kWh when diesel is subsidized visavis

petrol, when generator runs at 80% efficiency: instantaneous• Costs will go over Rs 25 per kWh without subsidy• Primary use today in organizations / offices

• Solar PV: Rs 7.50 per kWh when dc is used: day six hours• Electrical battery back-up: storage costs over Rs 15 per kWh• Ice-storage: ?

• Usage• Electrical Load: lighting, motor and electronics• Cooling Load

• What should one use when? How to optimize?• What to optimize? – costs, energy consumption, CO2

Euro1 = Rs65


Simulations


Rural Cellular Base Stations • Remote Base-stations providing communications

• Electrical grid is off for 16 to 20 hours• Primary operation costs for operators: diesel costs

• How to use battery back-up, diesel generator and solar power optimally to operate the base station?• Will ice-battery help? Certainly!

• Can we save energy at base station?• Especially energy needed for cooling• Will DC motors (for exhaust fans) and LEDs help?


Solar PV for Rural Schools• Rural Schools are used only during day time

• Primarily fan, some light and some electronics

• Solar PV with a small battery (grid-connected) would be a great solution• When sun-light is poorer, it is cooler and fan usage is lower• Why not use dc fans?• Why not use LEDs / CFL

• What should be DC line voltage?• 48V: Losses in line a consideration• What will be dc-dc conversion losses?


Urban Office• Primarily used in day time

• Solar PV can play a major role• Complimenting electrical grid

• Use of dc fans, lighting electronics will help• What should be line voltage? Will the losses be high?

• What will be losses in dc-dc conversion?• Will ice-battery play a major role?

• charged during off-peak early hours

• How to reduce evening loads?• Can offices start early and shut early?

• Today many start only around 9:30 am and continue till after 8 PM• Adding to evening loads – ac and lighting?

• Can we change practice from 8 am to 6 PM?


Smart-grids for India• Has to do much more than what is done elsewhere

• Smart-grids in India is to be used to• Reduce Distribution losses• Enable decentralized power-generation and optimize usage• Explore alternate methods of storage, including storage of heat (cool)• Handle peak-demand better• Manage demand and supply to meet creatively at all points of time, by

using storage and high-cost instantaneous power-sources• At local level• At neighborhood level• At district level, at state level, at national level

• Intelligently decide where to do load shedding if no other options• enable time of day metering with remote monitoring


Smart-grids and efficient appliances• Possible to come up with new low cost appliances

• Help increase usage efficiency and reduce wastage• Come with new devices and appliances, may be dc powered• Come up with better methods of cooling / heating and cooling / heating

locally if required• Figure out where dc can be used

• what should be the DC line-voltage

• Always watch for costs / investments required

• Smart-grids must help India move away from coal and oil to renewable resources as its economy grows


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Smart Grids for India Oct11