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Paul Hutton was recently interviewed by Sage Glass regarding the scientific evidence supporting the use of daylight in buildings. The interview is featured on the Sage website.

Click on the link below to see the article.

The Denver Metro Regional Science Fair was held this week. This year there were more than 600 entries from more 50 schools, up from approximately 550 students and 35 schools last year. The average quality of the projects I judged seemed higher than ever. This bodes well for science education in Colorado.

In the many years I’ve been judging science fairs, trends have come and gone. Topics kids select for projects are an excellent indicator of what is in vogue. Just a few years ago, a lot of projects related to forensic science, no doubt in response to the popularity of the many CSI tv shows. This year there was a decided decrease in those projects. It’s difficult to say what has replaced forensics, but I definitely noticed a lot of projects – 20 – related to sports.

Every year I select one Junior division and one Senior division project for our Hutton Architecture Solar Energy Award. The winners this year were clear cut choices. But I was disappointed there were fewer projects – only 14 – to choose from than in the last few years. I wonder if this could indicate a diminishing level of student interest in sustainability. Have economic concerns, or more trivial pursuits such as sports, pushed the environment to the back burner of our students minds? If the trend continues at next year’s science fair, then we’ll have the answer to our question.

One of my favorite projects at this year’s Science Fair was one that proposed to harvest useful energy from typical playground equipment. Many pieces of playground equipment convert stored chemical energy in children’s bodies into kinetic energy. The Science Fair project proposed to convert that kinetic energy into electricity through a simple turbine, much like a windmill.

The sample equipment identified was a typical merry go round. This was indeed a good choice, as a merry go round concentrates all that energy on the axle buried in the ground, where a turbine could conceivably convert some of that energy into electricity. Other playground devices would be harder to harvest energy from because there is no single point where energy is focused. Swing sets are an obvious example.

Suppose all the kinetic energy of a playground could be captured? How much energy is available? An average, active, 6 year old consumes approximately 1,800 calories per day. If that kid weighs 80 pounds and plays hard for 40 minutes, he may burn 200 calories. An average suburban elementary school holds approximately 600students. So, the maximum playground energy, given one recess per child per day, would be 120,000 calories. That equals 196 kWh. A typical school in Colorado consumes .13 kWh per square foot per day, or 9,750 kWh for the entire building per day.

So, capturing playground energy could reduce school energy consumption by 2%. That’s not a lot, but it’s a start, and it costs less than pv panels. But, we’d have to think of another name for playgrounds. We need something that sounds technical. For the time being, I’d suggest Kinetic Energy Recovery Zones – KERV’s for short. I can see that on our site plans already!

I heard on the radio this morning that all salaried employees were working for free today because in a Leap Year February has an extra day. The assumption was that salaries are annual and based on a standard 365 day year. Therefore a Leap Year must have one extra work day.

I understand the logic, but the unquestioning acceptance of this statement as fact immediately caught my attention. Something quite obvious to the mathematically literate has been missed. So I Googled the question “how many work days does a year have?” To my amazement, the vast majority of websites that attempted an answer also got it wrong. First of all, they all obsessed over the differences caused by different approaches to holidays. That’s understandable, but beside the point.

Let’s look at the math. There are not exactly 52 weeks in a typical year. There are 52 weeks AND one day in 365 days. So there are not necessarily 104 weekend days in a calendar year. 71% of the time there are 104 weekend days, and 29% of the time there are 105 weekend days. Not one of the websites I visited seemed to get this. So a typical calendar year has EITHER 260 or 261 work days, ignoring holidays of course.

So, what does happen with working days in a Leap Year? Well, there are at least 104 weekend days, so there could be 262 working days. But there could be 105 weekend days, in which case there may still be only 261 working days. But wait! There could be 106 weekend days, as in the case of a year in which January 1 is a Saturday. In that year, there would be only 260 working days. That’s right – you might work fewer days in a Leap Year than you did the non Leap Year before!

How can this be? It is the result of mapping a seven day week on a calendar year that never has an even multiple of seven. Mathematical patterns are wondrously complex and endlessly fascinating. What a great example of how math affects our everyday working lives!