Throughout the years there have been many different versions of “smart” electronics. Movies are full of ‘evil’ and ‘good’ appliances, from Robbie the Robot to R2-D2. And even some that are just part of the background, like most of the robots in Star Wars and Wall-E. The energy industry has also started to toss around ‘smart’ terms. Not just things like Ohm’s law or Restricted-Universe Census, but smart meters and smart grids. So what are they? Are they the same or are they different? What does “smart” mean?

First of all, smart is not an indication of how well a meter or a grid does on an intelligence test, how many times they beat me at checkers, or how well they plot to overthrow humans and use us as batteries. It has to deal with how well they respond with real time stimuli. Can the system adjust in a real time fashion; can it be run correctly by automation?

A smart meter is like any other electrical meter. It reads how much electricity you use, in terms of Kilowatt hours. The information that the smart meter can give you is far more than a Thomas meter. A smart meter can tell you in real time how much electricity you are using at any given moment. It can also show you your electrical usage over time. You can see when you use the most electricity (probably right after you come home). Armed with that data you can make informed decisions, such as deciding if you want air-conditioning to come on when you get home at 5 p.m. or if you want to avoid peak hours and have the air-conditioning running from 4 – 5 p.m. But a smart grid is something completely different.

photo credit: Neuwieser

Even though the electrical grid has been growing for over 100 years , it has yet to become smart. The current grid is set for a “use it or loose it” grid. That means that the grid should always have enough electricity to power everything that is currently on it. This creates two types of electrical generation. One is base load and the other is peak load. Base load is what is always on the grid. This is mostly created using coal fired power plants. A Coal fired plant takes a lot of energy to start up, but once you get it going it is easy to keep it going. Because of that coal fired plants are always burning coal. So when you’re at work and the refrigerator is still on, it’s part of the base load. Most of the time the base load handles all our electricity needs. However if there is a large spike of electrical usage, such as the one around 5 p.m. when most people get off of work, the base load is not enough. This is when they can bring on fast startup plants, usually using natural gas as the fuel, and supply the electricity during peak times.

The current grid is rigged for redundancy. The current electrical grid has grown up to offer multiple paths for electricity. This means that if one area of the grid goes down, the electricity can be maneuvered around the broken part. What that means in practice is that just because an area near you looses power, your power may not be interrupted.

Why would a smart grid be better? For our current grid we use mostly large scale power generation plants, but the smart grid would easily incorporate lots of small residential power generators like small solar panels on roofs and small wind turbines. The small solar panel and wind turbines on the current grid are unable to provide all your electrical needs. Even though they take in electricity all day long, they only have available what they are taking in at the moment. If there were a way to store all the electricity that they take in during the day when you aren’t using electricity, then it would help with the electricity you need, especially during peak times. Also in a smart grid, if you had an excess of electricity you could sell it to a power company. You could even sell it directly to people who need the electricity. You would go from one who can only consume, to a producer, seller and consumer of electricity.

photo credit: Mike Weston

How can a smart grid help us save money on our electric bills? Currently most electrical companies charge a single rate for electricity. That means that you pay a constant price for a kilowatt hour. The real cost of electricity is always in flux. The price has to do with what time of day it is, what season, what it was priced at yesterday, which power plants are down for maintenance, which ones have been reopened, the weather and many other variables. A smart grid would allow us to purchase electricity in real time. What if power plant B is selling electricity cheaper than power plant B at 3 a.m.? What if power plant A sells cheaper electricity at 2 p.m. than it does at 5 p.m.? Which one would you like to buy electricity from? When would you buy your electricity if you could store it? It gets even more exciting by adding smart appliances. What if you could tell you dishwasher to only wash dishes during the night if the cost of a kilowatt hour fell to a certain price? What if your water heater could find you a better price for the electricity used to heat water for your morning shower?

So is it green? What do we mean by green, it looks like cooper to me. The real question is how can this help save the environment and money (or if you’re more cynical, money and the environment). A smart grid would have the ability to allow small scale renewables to have a larger effect. In a system where a lot of electrical production would be done on residential or small communal solar cells, wind farms, tidal farms, or back yard geothermal plants, the need for large scale power plants would diminish. Large scale power plants will never be done away with. Mother Nature is far too capricious for that.

photo credit: frankh

Why do we need to change the grid if it works? The electrical needs for the country are expected to grow 30 % over the next 25 years. That prediction is counting on nothing new happening. What happens if we all switch to the electric cars during that time? Gasoline prices would drop, but electrical prices would rise, because electricity would replace gasoline as the fuel of choice. Right now that would mean building more and more coal plants.

On a smart grid, with most households having some small renewable power generation, the rise in electrical need may not lead to the building of more coal fired power plants.

So how long will this take? So far it has taken over 100 years to get to where we are today. When electricity first started being used most power plants where small and only provided enough electricity for a few buildings. Over time it became cheaper and more reasonable to have power generation on a larger scale. While this would not require us to reinvent the electrical grid, it would mean upgrading all of it. And all that would take more then four years.