'Smarter' Grids And Why India Needs Them
Everything is going smart these days-from the humble telephone to the good old refrigerator. The saliency of smartness is apparent when we contrast it with the dumbness of the earlier versions of these now smart equipment. The power backup market in India is growing between 10-15% and is the most definitive, though sad reflection of the unreliable power supply in the country.
So what is there in such a grid to be made smart? Here is a case for smart-grids from an Indian perspective.
So if there’s a smart grid, then what’s a dumb grid?
Electricity we use to charge a phone or run a fan is product of a complex chain of highly engineered systems touching, at times, delicate international relations. Electricity consumed as you read this piece, has an imprint of mining, geology, ecology, transportation, hydro, thermal, nuclear and mechanical engineering before it gets delivered in arms of electrical engineering which then routes it to your computer. Economists also find themselves involved deeply in the entire value chain from the production to consumption of electricity.
And still we have temerity to say that the old grid isn’t smart!
A lot of narrative on smartness revolves around IT, which brings us to the question-did the power sector never use computers before? No sir, power systems engineering was one of the very first which saw application of digital computers within first few years of computers making appearance.
Power systems have routinely used advanced telemetry, communication and control since past several decades. So a dumb grid was already sufficiently smart, else the power sector we know wouldn’t have existed. Thus, unlike other sectors, power sector’s smartness begins at a very high threshold.
Is Smart Grid an engineer’s fancy?
The world is approaching smart grids with increasing urgency for reasons which are vastly different, depending on the state of socio-economic maturity of the countries concerned. For the energy-surplus Nordic countries and those of continental Europe, it is about sustainability and lowered carbon imprint. For a country like Japan, it is about warding off existential threat from global warming and strategic implications stemming from complete dependence on imports for primary energy needs. For China, it appears to be driven by the big emerging business opportunity and strategic reasons (for the USA, the reasons are mixed).
However, for an energy-deficit, populous and geographically diverse and spread out country of ours, in Smart Grid lie solutions for energy poverty and universal energy access.
The key enablers of smartness are the bouquet of ideas for transmission, distribution and consumption (i.e. smart grid doesn’t end at your socket-it goes inside your equipment which is consuming electricity and interacts with the electricity flow mechanisms in the grid). A key concept is to make the grid handle not just MegaWatts but also Negawatts (kind of Demand Response, see the box). The bouquet I talk about has in it the distributed/embedded and intermittent generation as against predictable, centralised, extant mass electricity production factories; dispatch and packaging software which are nimble as against the mainstream day ahead planning, scheduling and despatch mechanisms- which can aggregate and schedule MegaWatts and Negawatts on same footing and with finer granularity.
Negawatts
- Option 1: Either generate more by so demanding a generator with spare capacity or,
- Option 2: Ask A to reduce consumption by the same amount which B needs.
Both are technically viable means to satisfy B’s incremental need. If option 1 gets exercised, the generator gets paid and if option 2 is exercised, consumer A can get paid who chose to not use the electricity which it was using.
Thus, one finds that decision of A to give up part of the electricity which it was consuming in response to the increased demand of B is similar to the decision to schedule greater generation. Former is like generation of negative power by A which adds up to increased power requirement of B keeping total requirement of A & B still the same, maintaining net generation-consumption balance in the grid. This is referred to as Demand Response.
The term Negawatts emerged by equating energy saved/avoided by efficiency measures with need of increased generation. Amory Lovins, pioneered the concept of negawatts and further promoted its linkage with the market. He boldly equated energy efficiency of equipment as equivalent to adding generation capacity.
Advanced IT tools now offer means to link negawatts dynamically to electricity markets on same footing as the generating capacity is committed & scheduled. This takes further the Negawatts concept as efficiency of equipment to the overall efficiency of use of electricity.
The Grid: Most Complex Machine Ever Built
The grid is acknowledged as the most complex machine ever built and is part of the biggest investment mankind has ever made in an engineering system-clearly these words indicate a very profound legacy.
Power sector matured about centralised and large generators which can be ‘scheduled’ predictably (if we need certain watts from 1015 hrs to 1030 hrs, grid managers can instruct and get a generator to put this amount in to the grid between these 15 minutes). The grid remains viable till the delicate balance between generation and consumption is met-akin to tight rope walk while juggling. Uncontrolled dropping of generation destabilises the grid similar to the sudden dropping of load (say a transmission line trips)-this is at the heart of a grid stability.
The grid acts as a giant flywheel which can take small variations in its stride, so long as the disturbances are small compared to the size of this flywheel (representing the size and number of generators connected to the grid together). However, if the predominance of generation in the grid (the size of flywheel) is fickle, clouds masking sunlight over a large solar power plant or sudden change of wind speeds, the grid would be destabilised.
The only way the grid can be kept secure and stable is to have fast mechanisms to match consumption and generation with needed nimbleness. The speed of response needed can’t be delivered by manual intervention (like in traditional despatch) but can be done by computers. Delivering situational awareness to the controllers is in itself a major technical challenge.
India’s need
For our country which has substantial sunshine and wind, estimates are rosy, but last-mile connectivity is at best patchy and repeated grid-level disturbances raise questions on ability of the national grid to work with massive infusion of intermittent and distributed generation.
Non-conventional generation is all set to now be inducted in greater numbers (reasons thereof need separate treatment).
So, the essential prerequisite for grant of universal access to electricity for all Indians is to bring the national grid to a level where it can absorb massive inflows of intermittent generation without affecting the grid stability along by creating and strengthening the counterweight of Negawatt aggregation, scheduling and dispatch at distribution level.
Though this is upstream (transmission) and downstream (distribution) requirement in the same breath, (sub) district level aggregation, scheduling and dispatch of Negawatts can be achieved with currently available IT tool set. With GoI backing penetration of electric road vehicles in same time frame as the ramping up of renewable generation, this aspect assumes urgency.
Disruption in Power Sector
How can small generation or choice of not using electricity (avoided consumption or negawatts) be aggregated, offered to the market, match to a customer’s need and close the contract between buyer and the seller? The answer lies in the liberating power of IT of creating networks and permitting fast and secure transactions even of complex nature.
This is something as liberating as AirBnB or Uber model of business, where IT tools permit aggregation and offering small capacities as meaningful quantum of electricity which can be used.
Can a short term contract be entered by my geyser or airconditioner with yours? Can variability in solar be offset by tinkering with air conditioners of big malls?
Why not? An Uberised grid would do that where my avoided consumption translates to real money for me. Unlike other sectors, the grid is an existing network. It can be easily made smarter by layering a communication layer over physical transaction of electricity.
Can need of switching on a DG set in a Gurgaon residential tower be avoided by changing thermostat setting of malls in the same area?
A unit of diesel generator produced electricity costs about Rs 25, which is about 3-5 times utility supplied power. In absence of utility power, the users put their important load on power backup (diesel generator (DG) or inverter). Thus, the users don’t mind spending as much as Rs 25 for a unit of electricity for their important loads as against utility supplied electricity at a fraction of this.
Lets take a case where there is a locality having a Mall in close vicinity, being fed by the same utility. In face of an unforeseen increase in the demand in the region, the utility manages the situation either by procuring additional power from the market or shed the load-forcing the users to switch on their backups. In new paradigm, the utility with needed intermediation, signal big malls to spare some of the electricity going in air-conditioning of large spaces by increasing thermostat settings and release it to be used in in the locality (large volumes being air-conditioned offer high thermal inertia-thus increase in thermostat settings would not be immediately detectable by people in the mall). The malls in turn get paid for their contribution.
This is classical demand response.
Similarly, in case of shortage of power in the grid where the utility is required to procure power at higher than usual rates, utilities can signal consumers to shed their non-essential loads and continue supply uninterrupted their essential loads albeit at a premium. Again this process can be automated and offer a cheaper alternative to backup power to the customer and for the utility-it can realise a premium at which it may be required to procure power. This would permit uninterrupted power supply on essential circuits and permit the utility to regulate consumption, charge and realise premium, which would still be a fraction of what a consumer spends on DG backup.
Remembering what iTunes did to music industry, when it was able to offer a single instead of an album, or what iTunes radio offers by way of off lining the songs which one likes, aggregation of avoided consumption (negawatts) can be despatched like a generator in response to a demand. This mechanism is inherently more efficient as the generators sitting at distance need not be asked to send power over long transmission lines-the demand gets satiated locally.
However, this calls for crowdsourcing or pooling of bits of capacity or avoided consumption before it can be offered. Uber and AirBnB have already done that in taxi and hotel businesses respectively. Time has come for the Grid.
This would give options to the users-specially commercial ones and housing societies to avoid use of Diesel Generation as the only fallback and only practical option. At the same time this idea holds key to practical alternative to the omnipresent and inefficient ‘battery-inverter’ in households. This is one very important idea which can go a very long way in mitigating abject and daily dependence on obscenely expensive-in rupee and carbon terms-the diesel generated electricity (and inefficient battery inverters for households).
Other aspects of smart grids
Off grid solutions like micro grids also lie in this bouquet of smart grid technologies, these are ideas which can enable retail electricity production and marketing. Though micro grids are exciting, but in a country like ours which has already invested/investing enormous sums of money in wiring the last village as structured programs, the policy makers and the citizens want the communities to be wired to the grid-being off the grid isn’t attractive for the communities. I don’t see micro/nano grids going mainstream vis-a-vis other options at hand in our country -at best they can be configured as UPS for the community, but how economics work out in such a case is to be seen. I have based my opinion on micro grids which draw upon solar energy (use of biomass/hydrogen/micro or nano hydel options for small communities in remote hilly locations can give fascinating results) but I reserve my comments on this presently.
So. . .
I feel that the term demand response is bit overused and passé. We should now talk about Negawatt aggregation and scheduling as this fits the mental and practice framework of power engineers.
Time to Uberise the grid has come.
(A small part of this article appeared as an opinion piece I wrote for a trade magazine, Power & Energy Solutions)