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The Wasteful American

The Wasteful American

In a new series from the
Null, the Wasteful American, a.k.a. Katelyn Sack, investigates ways in which we may or may not be squandering the planet’s precious resources. In installment one, the Wasteful American gets pedantic about pasta water.

Celebrity cook Rachel Ray tells viewers to salt their water before boiling pasta. That’s according to my totally dorky and marginally evil twin. Now, as salt raises the boiling point of water, this strikes me as an energy-inefficient thing to suggest 18 million people do regularly.

On the other hand, food cooking at a higher temperature cooks faster. So while salt water has a higher boiling point than water and will thus take longer to reach that boiling point, food boiled in salt water will subsequently cook more quickly because it is bubbling at a higher temperature to begin with.

Research question
Is there a net wasted energy (E) as a direct result of this salt-your-pasta-water business, and if so, are we talking about enough E to bother Rachel Ray (RR)?

Let’s do the math
Firstly, how many cooks are we talking about? I correct for the people who accidentally "superheat" (boil the water, then throw in the salt, causing their pots to boil over) with -g, where g = these goofballs, which I estimate at 1.5 million. I also subtract v for the lazy voyeurs who watch RR, but rarely or never actually try out her cooking tips. I estimate v at 2.25 million times 2 (accounting for lazy voyeurs and their evil twins).

So we're talking about approximately 12 million cooks, times however often they boil pasta, potatoes, or soup with salt in the mix. 12 million cooks times 3 cooking sessions per week = 36 million instances of wasted energy, E, per week. 36 million times 52 gives us 1,872 million instances per year.

Approximate annual wasted energy, E = 1,872 million multiplied by the difference in energy used to boil water or water-like liquid (such as soup broth) with, rather than without salt. That difference should be roughly the amount of energy used by a stovetop left on medium or medium-high for 5 seconds (the extra cooking time).

What's the waste then?
We can assume that every second difference means an energy expenditure of 0.00072 kW each second, and multiply that figure by 5 seconds to estimate a wasted energy per pasta pot of 0.0036 kWh. This means RR causes a wasted E of about 6.76 million kWh per year – a hefty societal fee for her bounty of creative cooking genius.

I'm not done yet
Since when does an Italian (or Italian-American) cook let you leave the table after one serving? Sit down. There's more.

If it takes about 15 seconds less for pasta to cook in pre-salted water, and it took only 5 seconds more for that salted water to boil, then the act of salting the pot before cooking has resulted in a net saving of 10 seconds – or about 0.0072 kWh per pot. 1,872 million times 0.0072 kWh gives us 13.52 million kWh saved by salting the water. This is (roughly) the same as the annual energy consumption of about 1,250 wasteful households, or an entire small town in Ohio.

Surely this can't be true...

Obviously, this is an oversimplified exploration, with especially insufficient data or explanations (not to mention truly atrocious estimations) for g, v, and all the other variables if I'm honest. For starters, different stovetop burners use varying amounts of energy, different folks use varying ratios of water to salt, and different evil twins start out with their water at varying temperatures. Still, it presents an interesting case of routine waste and accidental thrift by the famously buoyant and bumbling Americans (myself included).

More importantly, this is absolutely the wrong question of focus for people who want to decrease their quotidian energy use. Boiling cooking water with salt, only heating as much water as you need for that pasta dinner or cup of tea, and preheating the oven for ten instead of fifteen minutes are all useful and valid ways to conserve energy; however, the energy these behaviors save is far outweighed by the energy conserved when people refrain from long commutes and excessive travel, wear sweaters instead of cranking the heat, and routinely unplug computers and coffeepots and turn off lights and robo-cops when they are not in use.

The outcome?
Don't blame Rachel Ray.

My sincere thanks and praise to Mark Nandor of The Wellington School, who kindly provided his math and science expertise for this article. However, any remaining empirical errors or miscellaneous idiocies are mine alone.

Katelyn Sack regularly blogs about art and the creative life at Visiopoetics.

For wasted time, breath, heads and research funds, try these:

Timewasters Central
  Stop Breathing, Save the Planet
Jellyfish Grow Twelve Heads
  Studies of the Bleedin' Obvious
Image: Klaus Post

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08 Oct 2010
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