Coal (and others) by Wire

In the last post I talked a little about what electricity is and some of what it takes to make it. Today's power plants are behemoths of engineering, but that wasn't always the case, early electrification happened on a very small scale compared to today. If you have the occasion to see very old houses of the well-to-do, you may have seen personal power plants. Sometimes you might even see the remnants of old power plants at schools, though this could also have just been an external boiler room.

These early, personal or hyper local, power plants were necessary because making power is a whole different problem than getting it somewhere usefully and it wasn't until later that the long distance transmission of electricity was perfected. This page at the Edison Tech Center has some good information, the site as a whole will give you more history if you like.

What I'd like to talk more about is the "getting it there" part and also how that fits into the electricity world today. Everyone has seen transmission lines, they're towers and lines that look like this. Everyone has also experienced power outages. Perhaps one that was blamed on one of these in one of these. But what is the difference? How does that caged lightning move from those transmission lines into those small wires that feed into your house? The answer is transformers (not this kind).

What transformers do, at a very high level, is they convert the voltage from one level to another. Voltage can roughly be thought of as the density or oomph of the power. Stick your tongue on a 9 volt battery and it tingles, but stick your tongue in a 120 volt wall outlet and you'll be a human kabob. Now, the cutoff for being genuinely transmission level voltage is up for debate, but it's often around 110,000 volts ... or 110kv (kilo volts). The specific wires you see could be much higher than that: 238kv, 345kv, 765kv, or maybe even that 1,000kv line they're building in China. The reason that it's desirable to use these high voltages is that as you transmit power at higher voltages, you lose less in the process. Transformers allow you to "step up" your voltage so that you can move power across the countryside without losing much and then "step down" the voltage once you are near the homes that will be using it. The reason you want that lower voltage or oomph when it's near homes goes back to our first electricity fundamental: It is freaking dangerous.

To take us back to the big picture, there are three basic components of the physical electrical system: Generation, Transmission, and Distribution. If you look at your next electricity bill, you will probably see it broken out like this. If not, you're probably seeing Transmission get lumped in with either Generation or Distribution. Now, we haven't really talked about distribution yet, but let me give you this breakdown and it may become clear.

The three basic components of the physical electrical system:

• Generation: power plants, hydro dams, wind farms, etc. Anything that generates lots of power.
• Transmission: high voltage lines that carry serious volumes of electricity, but don't really connect to end users (most of the time)
• Distribution: lower voltage lines that pick up power "from the grid" and deliver it safely to your home or business.

Distribution is the portion of the network that connects directly to your house. If you're in the States most likely it's above ground and maybe you've called to have it moved or buried. In Europe it seems more common to have buried Distribution lines. Either way, the Distribution system starts at your electric meter and goes out of the building, where it will other lines probably at a transformer and be stepped up in voltage (not all the way to 110kv ... maybe just to 25kv) as it travels around the neighborhood. If you have an energy intensive business, maybe your shop is connected directly to these higher voltage wires.

In closing, the big take away is that the modern electrical system is commonly broken down into 3 major components (G, T, and D). Also, it was not always this way, hence the phrase "Coal by Wire" ... which is another way of saying "thank god that ash belching power plant can be built someplace outside of downtown!"

Two core facts of power

Any time a person sets out to understand the cost or price of electricity, they are likely to underestimate the task they are about undertake. This is not due to some public oversimplification, as you may find in the field of quantum physics (where article comments would have you believe there are quantum physicists lurking around every corner). No, the task is underestimated because the breadth and depth of knowledge necessary to understand electricity pricing is obscenely (unnecessarily?) high.

This isn't some national attempt at hubris, though, it's the glorious result of a mass of individuals trying to do the right thing in a competitive marketplace of ideas. So, enough with the big talk now, let's get some basics down.

First and foremost remember that we are talking about electricity. This is the stuff that will fry you dead, the stuff that turns on the lights, the stuff that lightning is made of, and is made of elections. This has a couple interesting impacts. Two big ones I'd like to mention are:
A) You don't know whose elections are where. Literally, it is impossible to tell where the electrons that are making your computer run came from. Quebec? Atlanta? Four Corners? Who knows? Any measurement that involves "delivering" or "sending" power rely on measuring the flow onto and off of "the grid." Any grid can be thought of as a pool with several hoses going in and several hoses going out. You pay for what goes into your hose, but you don't know where it came from.
B) You have never seen a time when more electricity was being generated than was being used (including dumping into storage) at the exact same moment. When your A/C kicks on in the middle of a hot summer night, somewhere a power plant turns up just a tiny bit. When your smartphone stops charging, somewhere a powerplant ramps down just a smidge. This is why renewable power isn't covering the planet, because if the wind starts to blow harder, something else has to stop generating (sounds good, right?). If the wind suddenly dies, somewhere a power plant has to pick up the slack... immediately... as in, less than 60 seconds. (That's the expensive part).

Second, compared to the energy we create with our bodies, a typical household uses an insane amount of power. If you used a bicycle to generate electricity for your house, you'd get about 100 watts per hour from it. The typical home, as a rule of thumb, uses 10,000,000 watt hours of energy per year. That's 10 megawatt hours, or 10 MWh. In other words, you'd need about 34 professional bikers, working in 8 hour shifts, riding every single day all year. That's for a house. As another rule of thumb, your average big box retailer (Walmart, Target, etc) that has a grocery section uses over 5,000 MWh per year (assuming a 1mw peak and a 60% load factor). That's 500 houses worth, or 17,000 bikers! To keep up with the demand, utilities and other power providers build power plants.

A power plant is an enormous, giant, heavy, dangerous piece of equipment that is necessary to generate electricity. A larger power plant that is operating well can generate about 7,000,000 MWh per year (assuming 1,000 nameplate and 80% capacity factor). That's 1,400 big box retailers or 700,000 homes or more than every living person in the New York City metro area biking away. That's a lot of juice! To generate all that power you need lots of fuel. Here are two photos that put things into perspective. A picture of a giant dump truck next to a person and also next to a coal mine. I use a coal example, not because I'm trying to promote it, but because it makes the volume of material required quite visible. Check out the Homer City Generating Station. Then, using a different tab, pull up your neighborhood. Check the measurement bar and zoom them so they are about the same. Just look at how huge that thing is. Then go just north of the smoke stacks and you'll see a big black splotch, that is the coal pile. The coal is stored there before it's burned. If you zoom in and look close you can see some pick-up trucks driving around the pile and they look so tiny.

So, we didn't necessarily get into anything fancy or altogether to detailed about electricity this time. However, these two facts will appear over and over again. It's important to remember at every single level of the industry decisions are driving by (among other things) the fact that electricity is dangerous as hell and is made by huge, enormous, machines.