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I've always thought that would be a good headline.
Now that I have your attention I have to report that Emily McKie, my daughter, is the author of a new e-book on Smart Grid technology in her sustainable cities series.
'What's Smart Grid?' I hear you cry...
Smart Grid technology employs electronics and computer science to optimise electricity grids.
From a consumer's point of view the most obvious feature is an electronic electricity meter that charges different rates depending on supply and demand. It's like off-peak but sexy. It provides more sophisticated load-sharing.
At present if you have an off-peak meter and separate off-peak wiring in your home: water heaters; clothes dryers; dishwashers and electric vehicle charging can be done at a lower tariff when demand is low. Your circuit is turned on and off by the suppler using a coded pulse sent along the power lines.
Smart Meters do a similar thing more frequently in response to price signals from the wholesale electricity market and can incorporate more high current appliances like fridges and air-conditioners. They may also allow those with solar panels or perhaps wind turbines or combined energy systems to feedback electricity to the grid.
Yet there are some risks:
- Software has bugs so energy software will have bugs too.
- Brittle energy infrastructure is optimised for efficiency, but efficiency isn’t very robust. A robust system would operate even when part of the system fails.
- Breaches of Privacy – A growing issue in our modern era is the amount of information we willingly and unwittingly share.
- Financial risks – The offer of cheaper energy for consumers is contingent on several factors. ...Perhaps only those with the ability to invest in energy storage will come out ahead.
But I'll let you read Emily's e-book if you want to know more about the benefits and potential pitfalls.
Emily is an engineer and most recently has been working for a solar power company in Berlin. That makes her quite unique because in addition to being female, her great-grandfather was one of the first engineers to be employed in the electricity generation industry. For more information read about the McKie Family - click here.
These days most of us take electricity for granted. So it's easy to forget just how recently electricity became a commodity.
I'm now seventy years old. A little over a hundred years ago there was no reason for the average household to have electricity at all. When I was in primary school one kid in my class had no electricity at home. His mother asserted she could get along perfectly well without the devil's work (or an electricity bill) - as some view a microwave oven or dishwasher today.
The initial impetus to get connected was the advent of convenient electric light. And that didn't exist for the general public until 1881.
That year the first light-bulb manufacturing factory in the world opened its doors in South Benwell, Newcastle upon Tyne, just two miles from the McKie Soda Water factory.
It was a joint venture between Thomas Alva Edison and Joseph Swan, a Novocastrian and the first man to patent the practical electric light bulb, beating Edison to that goal by several years.
But Edison was nothing if not a salesman. Suddenly wealthy people wanted electric light. Large country houses, then public buildings like hospitals and large retailers, installed generators. Soon electric streetlights vied with gas and local government became involved. Meanwhile electric trains and trams began to replace steam and horses.
Electricity generation and distribution became a boom industry with thousands of electricity companies springing up worldwide. Those households with electricity soon discovered other benefits like new electric appliances with heating elements and electric motors, then they wanted those new radio/wireless thingies.
Meanwhile as the first 'Model T' Ford rolled off the assembly line in Highland Park, Michigan, Emily's great grandfather James and his brother Tom had both forsaken the family water business to become electrical engineers.
Apart from providing large houses and so on with electric lighting there were many ships being built on the Tyne. Each of these needed electric lighting as well as electric motors and early radio technology that needed generators and the associated cables and switches and James McKie became the chief engineer for the largest supplier.
Each distribution arrangement for a large retailer; office block; factory; ship; or local street lighting installation was what we might call today a micro-grid - a small independent generation and consumption site. And as I have explained elsewhere most then employed DC (direct current).
All this might be interesting history but so what?
Well, after reading Emily's e-book and thinking about her ancestors it occurred to me that DC micro-grids might stage a comeback. They already have in many off-grid situations. Wendy's cousin Gary lives off-grid near Darwin as did my brother Peter near Jindabyne.
These off-grid installations rely on solar panels and batteries - DC. Now with LED lighting, cellular phones and computer tablets that run on 5 or 12 volts DC (as do almost all computers and televisions internally) there is little need for AC (alternating current) except for appliances with synchronous motors. For these off-grid systems need one or more inexpensive inverters. Thus most of their electrical power is DC.
DC, like the electrical systems in your car, has many advantages. It uses cables more efficiently and has no radiation losses. New motors, like those you see in those drones you see people flying or in those new electric bikes, are lighter, more efficient and more powerful then older AC or DC designs. So some new motorised domestic appliances are already employing them and claiming up to 40% energy savings.
The downside to DC micro-grids, as my grandfather's company discovered, was that in those days the engines that turned the dynamo ran on coal or petroleum and were not reliable unless continuously tended by a person. Lots of small generators also generated lots of noise and lots of pollution (as you can see any day in India when the grid fails). Linking them together in a comprehensive grid allowed: very large scale integration; efficiencies of scale; labour reduction and more reliability. It also facilitated energy and capacity swapping across large, more efficient generators.
Increased efficiency and cost savings more than compensated for the increased transmission losses as electricity got shipped about over long distances.
When it came to constructing a grid the DC technology of the day failed. DC dynamos faced serious technical, cost and efficiency issues scaling-up in the days before semiconductor electronics. AC generators, known as alternators, can be almost unlimited in size and are very efficient converters of mechanical energy. This is why your car has an alternator, even thought its output has to be converted to DC to charge your car's battery.
Further AC had a killer advantage - inexpensive transformers that convert current to voltage and vice versa. These enable the grid to be layered, with very high voltages and relatively low current for efficient long links across the countryside and low voltage but high current for local distribution where high voltages would short to ground, cause fires and kill people.
But that was back in the 20th century. Now with electronic inverters DC is preferred for very long high voltage transmission, particularly underground or underwater.
What if this century we went back, like off-grid households, to DC mini-grids? What if we progressively converted each local distribution area to a series of cellular DC mini-grids? Progressively, inverters could replace transformers on power-poles (and in those humming boxes in the street) so that households could be offered AC and DC supply during a transition period. By cellularization back to mini-grids the vulnerabilities of scale; complexity and to attack identified by Emily in her e-book could be substantially reduced or eliminated.
I could now go into a long technical explanation as to why this would be advantageous. I could detail efficiencies and savings and environmental advantages. I could point to the risks that Emily has identified. Yet near the top of the list for me would be a posthumous vindication of my grandfather's commitment to DC.
Instead, for the time being, I'll simply record my pride in my daughter who is, quite serendipitously, following on in the family footsteps unto the fourth generation - DC generation of course.
Her partner Guido is also an engineer developing solar systems, so perhaps my grandchild (or children?) might play a role later this century?
To read Emily's paper click the image of its cover above or to go to her website: Planned Cities - click here
If any of this was interesting you might want to visit other articles on this website: