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Comment by gcv | Hacker News Reader

Fascinating stuff. I wish a northern state, like Montana, would try a similar experiment in half of its counties, and ditch daylight saving time for a year and see what happens. I suspect it would save money, too.

On a slightly more hackerish note: I worked on a power trading system, and it would break like hell twice a year, on DST switch days. Because electricity trades on an hourly basis (except in Texas, which uses 15-minute intervals), everyone who deals with aggregating power flow or power over the course of a day, ends up writing a loop like "for (hour = 0; hour < 24; hour++) { ... }", which is totally wrong. The spring forward day has 23 hours, and the fall back day has 25. That code therefore breaks twice a year and loses money because (a) it needs to be fixed, and (b) it did its accounting wrong. I hope studies examining the economic efficiency of DST take this sort of thing into account. Probably not.

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Probably not, but I'm used to living way more north than Montana and actually more northern than London where the time change is based on for the UK. I have to say it is needed no matter the economic effect, when for over 2 months you see no sunlight what so ever during a working day it has an abysmal effect on worker efficiency.

I have only observations to base this on, but workers start dropping off well before 'flu season'. I do a lot of work outside and I find the comments about DST harming farming to be irrelevant; the main one is that harvesting labour becomes in efficient as crops have to be harvested after the dew. If I didn't need workers at 6am I'd tell them to come in at 7 or 8am when the crops are ready to be harvested. That's just common sense; if I'm working outside, I'm not going until it's safe for me to do it and if its too dark I'll tell the customer I'm coming later, if they don't like it lump it.

Although, on my more hackerish note: 2 million candela torch + power inverter = sun rise at 3am. I believe it's supposed to produce sunlight-like brightness over some 450m^2, although it isn't always useful and without it being hooked up to some form of power it's out of batteries within 15 minutes.

Simple change to:

  for (hour = 0; hour < Today.hours; hour++) { ... }

... where the hours method of the Today class would check the date and return the right number of hours would fix that right up.

Of course, it may not really be that simple, but tons of operating systems and other software handles DST just fine nowdays. I don't see why this is a real programming problem.

From the article: In 2005, Reps. Edward J. Markey of Massachusetts and Fred Upton of Michigan drafted legislation that would extend daylight-saving time nationwide. Congress approved the amendment, which called for clocks to be sprung forward three weeks earlier in the spring and one week later in the fall. The change went into effect last year.

Dear legislators, if you're going to fiddle with the representation of time, please could you do it with a minimum of three years notice. This would save a vast effort in retro-fitting critical system upon which all of society depends. Providing sufficient notice would be vastly more cost effective and therefore more productive for everyone.

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