Another Day, Another Dollar

When I meet someone, there is always one thing I am the most curious about….

What do they do? Are they an architect, accountant, stay at home mom, construction worker, sales representative? 99.99% of the time my guess is wrong and I am usually shocked to hear of their real occupation. (I find I usually don’t give people enough credit!) I still see it scary that my graduating class is in the real world making serious decisions that affect our health, economy and government. We are helping run the world, and I don’t know about you, but this scares the poop out of me! Companies trust us – crazy!

I enjoy listening to my friends tell me about their jobs. It makes up so much time of their life and helps me get to know them better and where they are coming from. I have a lot of friends ask me all the time what I do and usually I just answer, “I am an engineer at Duke Energy.” It is the easiest way out. But then those curious peeps dig further, “Well, what kind of stuff do you do?” And then the cat is out of the bag and I know a 30 minute conversation is in front of me. Majority of the time no one understands what I do because they cannot grasp the concepts of electricity and how it is generated.

Therefore, here we go, a little explanation of what I do at my job:

I work for Duke Energy as a short term load forecaster.

First off, some quick definitions:

Load: demand on an energy producing system

Peak load, peak demand: these two terms are used interchangeably to denote the maximum power requirement of a system at a given time, or the amount of power required to supply customers at times when need is the greatest.

Generating Unit: these are the individual units at each coal fired plant, nuclear plant and hydro plant. Each unit operates independently and most energy production facilities have more than one unit (i.e. Marshal Steam Station, McGuire Nuclear Station, Belews Creek Steam Station http://www.duke-energy.com/power-plants/franchised.asp -check it out, educate yourself!)

Now, using historical data, mathematical models, temperature forecasts, humidity forecasts, holiday and school calendars, and some of my own common sense, I produce a seven day hourly forecast for Duke Energy’s Generation and Bulk Power Marketing floor. Therefore, I put out a forecast that gives our unit commitment individuals an idea of how much energy we need to have on our system each hour to meet our load demand for our service territory. With my forecast, the unit commitment turns around and “fires” our system of individual units to meet this demand. The key here is to “fire” this system economically. Each of our generating units operates at various costs depending on many factors. Therefore, if another utility is selling power for only $30/megawatt and the cheapest we can produce it at with some of our units is $45/megawatt, then it is a more economical decision to buy power from the other utility instead of turning on another unit and producing it ourselves. The whole thing is a huge balancing act. How can we meet our needs at the cheapest cost? So I work with the power traders, meteorologists, and unit commitment guys to make these decisions.

The load forecast is an hourly curve of energy consumption by the customers in the utilities service area. A utility has to make sure they have enough power on their system to meet their peak load demand, but also be able to regulate that generation down during off-peak hours so not to overload the system.

For example: In the winter, the highest peak demand is at 8am. Why? Because everyone is waking up; your lights are coming on, hot water heaters kick in for you to shower, you are turning the heat up so you don’t freeze when getting out of bed, and offices and schools are opening up. You are nearing a morning peak demand. As the sun starts to come up, street lights turn off and the sun starts to heat things up and your heat systems start to regulate down. Then energy consumption continues to fall as the day gets warmer. Therefore, it is my job to forecast that peak number at 8am and the other 23 hourly numbers on either side of that peak to make sure we have enough electricity on our system so that you can go through your morning routines.

I do this for seven days out, every hour. I then monitor and update this seven day forecast on a real time basis ensuring we are continually running our system economically.
That’s it, that’s what I do. How did I get into this….I don’t know. But…it’s a job, and I am doing it.
What about you? What do you do?