The mercury in CFLs is more than offset by the reduction in airborne mercury(a worse form) savings in energy production (as compared to tungsten lights). And, how do you know "the vast majority" are not recycled?
When LEDs become the dominant light source, will we then have a low voltage DC wired through our houses for light fixturing, eliminating any need for LED bulbs with extra circuitry?
Your right except: When the real energy supplies start costing more, then efficiency and low usage starts paying for itself. It does very little good to rant and rave about energy usage or dependency; until the cost is reflected in prices. It might buy votes to keep energy prices low but it's a disservice to our children.
I do not think LED will lead to energy savings. Although LED is a lot more energy efficient per unit, as the cost of LEDs comes down, people will find a lot more uses for it, therefore dramatically increase the number of units installed. The safety cloth is a good example. Same argument was made for paper when computer became widely accepted, but people end up using a lot more paper.
You are right except for one caveat--the environment. Every day I hear of a new solution to the "barrier film" problem--today it was nanoparticles that fill-in the pores which allow moisture and oxygen to spoil OLEDs on plastic substrates. Unless one of these "breakthroughs" actually does solve the barrier-film problem, OLEDs will never get printed on web presses, but will always need glass substrates (and thus will never achieve price parity with fluorescent).
Luminous output is catching up fast--in fact by 2012 advanced gallium nitride LEDs are predicted to become the brightest light source on the planet--even brighter than arc lamps. The price, however, is going to come down gradually as volume ramps up.
The thing I like about the LED luminares is that their light quality is better than fluorescents--at least in the models designed to provide "warm" light. Before I use a CFL, I have to judge whether I can put up with poor light in that location. High-end LEDs rival halogen. But, as you say, the price has got to come down. I'd guess that $10 a bulb would convert most people and $5 the rest.
What are the engineering and design challenges in creating successful IoT devices? These devices are usually small, resource-constrained electronics designed to sense, collect, send, and/or interpret data. Some of the devices need to be smart enough to act upon data in real time, 24/7. Are the design challenges the same as with embedded systems, but with a little developer- and IT-skills added in? What do engineers need to know? Rick Merritt talks with two experts about the tools and best options for designing IoT devices in 2016. Specifically the guests will discuss sensors, security, and lessons from IoT deployments.