1. LED lighting

2. LED  Inverse of PV  Benefits from the same cost curve http://www.eia.gov/todayinenergy/detail.cfm?id=15471

5. Form factors

6. Pi Zero

7.  $5  1Ghz, Single-core CPU  512MB RAM  Mini HDMI and USB On-The-Go ports  Micro USB power  HAT-compatible 40-pin header  Composite video and reset headers

8. Pi Light Light control protocol - measure - actuate

9. GreenLight

10. How big a store?  7.4 V 2200 mAh = 16.2 Wh  1 5W LED for 3 hours  $9.19 from Staples!  All prices decreasing exponentially