Doesn’t anyone have editors, part 18,000

So I’m finishing up the October Wired (read, as usual, in brief spurts in the most appropriate room for Wired). And I run into a “WiredU” feature. Much or all of which I could grump about, but that would be taking Wired far too seriously.

And then I hit “Waste Studies,” a supposed course about waste, which features as a Guest Lecturer Saul Griffith, who apparently figured out how to audit his total energy consumption, not just the household consumption. (And found, in the process, that he was a wastrel–he was flying a LOT, apparently). So far, so good.

But the big infographic on Griffith’s energy consumption has this as the total headline:

Saul Griffith’s 2007 Energy Consumption: 18,000 Watts

Which is pure nonsense. No, I’m not willing to spend half an hour on a TED talk to see what Griffith actually said. I’d be very surprised if he said “I consumed 18,000 watts n 2007.”

Watts don’t work that way, and Wired should know better

You can no more consume 18,000 watts, with no additional qualifications, then you can go on a journey that’s 60mph long.

Watts measure rate–not quantity as such. If you have a 2.5kW photovoltaic generation system (as we do), that means the system is rated to generate 2,500 watts as a maximum rate of generation (or, most likely, somewhat more than that)…just as your car may be limited to go at a maximum speed of 120mph. Speed is a rate: it’s not a quantity as such.

Calories, miles, pounds, meters, grams: Those are all quantities. The equivalent for electricity is kWh, kilowatt-hours:  One kWh is 1,000 watts for the period of one hour.

I’m pretty certain Griffith didn’t find that he used 18,000 watt/hours or 18kWh of energy in 2007: That would be incredibly low. (Our household electricity consumption over the last year was about 4,000kWh, and we run a very energy-efficient household…and that doesn’t count all the other uses of energy, including gas, transportation, etc., etc.)

It’s possible that Griffith found that his average rate of energy consumption was 18kW. That would translate to 157,680kWh for the year, and that is a lot of energy. On the other hand, the pie chart says gas and electricity only represented 6% of that, and 9460kWh for gas and electricity is actually pretty good–the average U.S. household uses more than that in electricity alone.

I’m not blaming Griffith for this. I’m about 99% certain he didn’t use 18,000 watts as a quantity. I’m blaming the Wired writer and editors. For a magazine that claims to be knowledgeable about technology, that level of sloppiness is hard to excuse.

2 Responses to “Doesn’t anyone have editors, part 18,000”

  1. I probably shouldn’t have dug into this, but I did anyway …

    It turns out he does *mean* average rate of energy consumption, but he also does make it very, very easy to misread it as a quantity. He keeps trying to put things in terms of comparison to 100-watt light bulbs burning continuously, which leads to much quantity vs. rate switching when e.g. he derives a rate from a few quantities in a year. It’s clear he knows the difference and he’s trying to make the topic “accessible”, but also very confusing. See:

  2. walt says:

    Arggh… I still fault Wired for not correcting this manifest stupidity, but clearly Griffith is also to blame. “Watts per always” turns a meaningful concept into mush. The more I read into that PDF, the more I wanted to scream, until I finally just stopped.

    The way to make abstruse measures understandable is not to introduce even more abstruse notions. Anybody who reads their power bills knows about kWh: that’s a concrete, measurable, sensible notion. “Watts per always”—oh, geez. It makes my head hurt even typing that. Nobody except the Livermore Fire Department leaves a light burning “forever” (and eventually that tiny little bulb is going to burn out), and most of us have very few things that consume the same amount of power all the time. He’s also conflating all sorts of different kinds of power, which from an environmental standpoint is not helpful.

    Double-arggh… Anyway, thanks for clearing this up: Wired only deserves part of the blame, for going along with this nonsense. And making it worse by not spelling out “Watts per always,” bizarre as that is.