I remember reading many years ago, when solar cells were much less efficient, that a cell would have to be used in average sunlight for 27 years to generate the energy that was consumed in making it in the first place. I presume that number has gotten much better since. But it would be nice to know what it currently is.
Solar Thermal is also a very good candidate for warm areas like the middle east and/or deserts elsewhere. Some remarkable work is being done in Spain regarding this technology. It certainly is more steady than PV and Greener too.
I had mentioned this fact about over a year ago here in these discussion forums.
When these plants were in the US IC or solar, we had good gov oversite of the release-containment-re-use of these chemicals.
Or we had just gotten to a point we could.
Then it all shiftede to the wild, wild east
Where the rush to build and produce took over the need to not polute.
The chinese will have created more greenouse gas emmissions in producing PV than all the Co2 reductions will ever have a chance to undo.
When working for an electronics manufacturer in the late 90's when we moved manufacturing to Mexico the first thing we did was remove the extended condensation hoods for our cleaning tanks using the US certified CFC solvents to use the solvents still legal in Mexico - that was progress in the wrong direction. I wonder what the laws are in China and other countries we manufacture in.
You always see these "contains" or "uses" canards
thrown out by people whose agenda it suits, but no
quantitative emissions numbers, and of course the
process gasses could be recaptured in situ if the
manufacturer cared to.
I've worked with flash X-ray machines which are
just "lightning in a bottle" with the bottle full
of SF6. But the bottle stays corked and losses
are nil. Process gasses have to flow, but you
don't see a whole lot of HF, silane, borane being
vented (at least, not in the US, not these last
few decades - but in the old days the industry
sure did stank up some groundwater, dirty little
non-secret). The feedstocks can flow to reclaim.
But that is insufficiently scary to be useful in
promoting whatever the "heck" these people are
It's absurd, by the way, to call an inorganic
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.