This

TED Talk is not that new, and a bit longer than usual, but the speaker does a pretty good job of summarizing how to set up photovoltaics in your home. The main reason I am posting this is because, much like

Lab 3-9 (Photovoltaic Cell Dynamics) and this

corresponding video, the speaker presents a calculation for how many years are needed for the photovoltaic panels to pay for themselves. He bases his calculation on the "cost per watt hour" of photovoltaics. My calculation is based on "cost per square meter". Since photovoltaics are usually sold in terms of cost per watt hour I had to do hours of internet research estimating what they cost per square meter. At any rate, for students doing simple experiments, using "cost per square meter" for the calculation makes more sense. Interestingly, despite our different methods his estimate for how long it takes for photovoltaics to pay for themselves is

identical to mine: 10 years. Granted, he incorporates tax rebates into his calculation (I don't), but his calculation is a year older than mine. It is possible that prices had fallen even further in the course of a year, so this may explain why I get the same value in the absence of these rebates. I concur with his observation on the dramatic decline in photovoltaic prices because based on my calculations in early 2012 (available in the instructor's guide to the first edition of the manual), you would have needed 25 years for a photovoltaic to pay for itself. What a difference two years can make!