By Antonio Ruffini, Editor, ESI Africa magazine
Like many nebulously defined concepts smart grids, mean different things to different people. One view is the rather science fictional concept of a grid where everyone can off-take the power they need but should the price be right it would be nice to switch on their genset and pump a bit of power onto the grid. Or more likely a smart building, festooned with photovoltaic panels, underutilised on a public holiday would like to feed its excess kilowatts onto the grid, and the company management can tell its shareholders how it earned some extra cash while helping save the planet. Thus, a grid with thousands of suppliers and off-takers, all smartly coordinated with the aid of efficient market mechanisms.
When some people who are not particularly close to the electricity sector close their eyes and envision smart grids they see a scene where nice clean green energy sources – none of this dirty coal stuff or dangerous nuclear stuff or those horrible dams that flood everything – provide all the power they want when they want, and on top of that give them a chance to contribute. It is a vision of things being a bit more like YouTube, Twitter, Facebook where everyone is a content provider, where everyone is interconnected, with, by the way, opportunities for entrepreneurs to earn a living.
For the average distribution utility trying to keep body and soul together, any temptation to forcibly stuff the heads of such visionaries into the nearest toilet is understandable. Their reality is something like this: Small customers, upon seeing their power go down, phone the utility’s call centre which may or may not be able to say it knows about the fault in the area and even if it does usually can only say the cause is being investigated but can’t really say when the power will be back on. It may be as soon as a team can get there and find and fix the problem.
Those distribution utilities not totally incapacitated by skills shortages are trying to keep their ageing infrastructure going, hoping they can spend their annual budgets on as much of the most critical essential equipment upgrades and maintenance as they can as opposed to blowing too much of it on cable theft-related repairs and similar rubbish.
The reality in sophisticated Europe is that when the wind blows and the sun shines it tends to do so in wide bands and there is excess electricity to export, to someone, and when the wind dies and it gets cold and dark a lot of places want to import. So, those nasty base-load stations do still have their uses – but, oh, wait, you can’t just start them up by pushing a button when the renewables generators fall away en mass. It takes, like what?, hours, half a day, and you have to do what?, like keep some of those things spinning and burning fuel just in case?, or alternatively, ... oh, I see...
It means you need fast-to-bring-up gas turbines, and pumped storage would be nice. With the planned renewables capacity in South Africa, the country’s 2,750 or so MW of pumped storage capacity once Ingula is completed, is going to be very important indeed.
Now we get to the reality behind the push for smart grids. Fact is, the green revolution means grids have to be smarter to manage this variability in supply. That and economic and power constraints are giving the smart grid movement impetus rather than any particular dream to give Sam’s Paint and Body Shop the chance to manage its electricity demand more conveniently. It means greater sophistication in choosing shedable loads while keeping up other more critical loads.
Another driver is that utilities can only provide services if people pay for them and sadly that only happens if utilities (and societies, for utilities can’t do it alone) can prevent them from avoiding doing so. It means having meters and systems that detect tampering. It means being able to disconnect and reconnect easily without wasting manpower. It means knowing the system’s energy balance, where it is losing energy.
But the customer today is not just sitting back either, and is more powerful and better informed, with higher expectations. A trend sweeping the industry is the quantification, measurement and reward/penalisation of utilities based on how many hours, no, minutes, and in a jurisdiction like Singapore, seconds that users are left without power per year. In Europe the rewards and punishments are in the order of millions of euros a minute for good or bad performance.
Smart grids are about the convergence of electrical engineering and information technology, about open architectures, about incrementally upgrading networks and equipment to try and compensate for shortages of resources and funding while keeping the power from more variable sources reaching customers, while keeping the system in balance.