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Smart-Grid in Indian Context. Ashok Jhunjhunwala, IIT Madras ashok@tenet.res.in. Indian Context. Euro1 = Rs65. 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
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ICT Empowered Grid Smart-Grid in Indian Context Ashok Jhunjhunwala, IIT Madrasashok@tenet.res.in
ICT Empowered Grid Indian Context
ICT Empowered Grid Euro1 = Rs65 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
ICT Empowered Grid India’s Fuel-wise Generation-Capacity (MW) • Generation capacity continues to increase • Keeping pace with country’s rapid (8 to 9%) economic growth
ICT Empowered Grid 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
ICT Empowered Grid 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
ICT Empowered Grid 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
ICT Empowered Grid Euro1 = Rs65 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
ICT Empowered Grid Towards solutions For India’s energy problem
ICT Empowered Grid 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
ICT Empowered Grid 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
ICT Empowered Grid 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?
ICT Empowered Grid Sun shines brightly over India • 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 Euro1 = Rs65
ICT Empowered Grid Euro1 = Rs65 Energy Storage • 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 Rs16.3/ 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
ICT Empowered Grid When do the demand peak in India? Sept 23rd • 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 May 19th May 2nd Feb 9th June 6th
ICT Empowered Grid 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)
ICT Empowered Grid Some scenarios reduce consumption of substantial quantities of diesel, kerosene, furnace oil
ICT Empowered Grid Euro1 = Rs65 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
ICT Empowered Grid Simulations
ICT Empowered Grid 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?
ICT Empowered Grid 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?
ICT Empowered Grid 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?
ICT Empowered Grid 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
ICT Empowered Grid 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