Ecocentricity Blog: An Electric Analogy
If we want to champion more renewable electricity, I think we should understand the difference between a kilowatt and a kilowatt-hour, if only so that we have more credibility on the topic.
I often find myself thinking about energy, specifically electricity. Electricity is so ubiquitous – I bet you’d be hard-pressed to find someone who hasn’t used an electron within the last 24-hours. Every single keystroke I hammer out is powered by the electric grid, and few things inconvenience us more than when our power goes out. Moreover, how we power our world has tremendous environmental consequences, from greenhouse gas emissions to coal ash pond accidents to siting considerations to fracked mountain ranges.
And yet, for how common electricity is in our world, I get the impression that many people would struggle to explain electricity’s fundamental units of measure. To be clear, I’m not trying to shame anyone! I even had to look it up to make sure I had it down. That said, I’m a believer that we need to understand the fundamentals of something to change it. If we want to champion more renewable electricity, I think we should understand the difference between a kilowatt and a kilowatt-hour, if only so that we have more credibility on the topic. And so, the rest of this post will by my silly use of an analogy in an effort to demystify the measurement of electricity.
Suppose that you own two dogs.* One is large, rivaling some small horses in size, while the other could fit in your backpack in a pinch. Both go bananas when it’s mealtime, but you’ve grown tired of patiently measuring their bowls of food while they bark excitedly. You’ve come up with a brilliant innovation.
Having studied their eating habits meticulously, you have calculated that if you let them eat as much as they want for 20 minutes three times a day (so one hour daily), they get just the right amount of food. For your large dog, that shakes out to one small bag of food per day, while your small dog consumes one small bag of food every seven days. So you buy yourself a kiddie swimming pool, stick it in a closet, and dump in 8 bags of food every Monday morning, knowing it will last you the week. When it’s mealtime, you just open the door and let them go at it for 20 minutes. Brilliant!**
Okay, so how does a kilowatt hour fit into this? A kilowatt hour is an amount of energy that is used, so in my analogy, it’s like the small bags of dog food you buy each week. Your large dog consumes seven of them a week, while your small dog consumes one of them a week. And when you pay your electricity bill each month, you pay per kWh, just like you pay per bag of dog food you buy. Easy, right?
Now, how about a kilowatt? That’s a measurement of the rate of consumption. Your large dog consumes more food every time it eats than the small dog, even though they both chow down in 20-minute increments. It’s like the difference between your vacuum and a light bulb – if you turn both of them on for 20-minutes, the vacuum will consume more energy than the bulb. That’s because it has a higher wattage than the lightbulb, and wattage is a measurement of power. It’s a “hungrier” device, just like your big dog is hungrier than your little one.
So there you have it – the basics of how we measure electricity, in terms any dog-lover can understand.
* Disclaimer: No animals were harmed in the making of this silly analogy.
** Another disclaimer: I have no idea if this is brilliant. It’s probably a terrible idea. I don’t own any dogs. You probably shouldn’t try this for reasons I have no way of knowing. You’ve been warned.
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