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Plumbers and electricians would be next on my list of professions, which should not require certifications

Prepare to be shocked.

Maybe. Construction has been a shitty, shitty industry of late. Yeah, not all electrical work is new construction, but they're correlated.

Be careful sizing a backup generator when a large part of its load will be switching supplies and UPSes. UPSes in particular have _very_ strange load waveforms due to the rectifiers that are used in the charging circuit. The harmonics passed back on the line can cause the generator to 'seek' trying to lock in to 50/60 Hz, which can cause significant damage.

A permanent magnet generator can help, but they're a little more expensive.

http://ecmweb.com/news/electric_ensuring_generator_ups/

http://www.physicsforums.com/archive/index.php/t-186969.html

Motors aren't the only reason for low power factors. Non-linear loads such as switched power supplies and, yes, CFLs, also decrease the power factor. If residential homes are doing this on a large scale (and transition to CFL or LED will accelerate this), the utilities will have to deal with it. It is likely that they will eventually start charging residential customers based on PF as well, once they have the infrastructure in place to reliably measure it. See here, for example: http://ecmweb.com/mag/electric_perplexed_pq_issues_3/

I wasn't talking about the UK specifically, but urban areas in particular. Having cities which do get lots of sun have these, like all the California cities, Las Vegas, Phoenix, Dallas, Houston, Atlanta, Miami, etc. etc. along with Chinese cities, Mexico city... it would help out the energy problem tremendously allowing for other areas around the world to use other means. And, with mass production of solar panels of this type, it would lower the cost, along with lowering electricity bills of those buildings since they wouldn't even need an outside source to give them electricity. So whoever builds the buildings would pay for it, because they would be saving money in the long run. Also, if all goes well and more than enough electricity is created, they could sell it to buildings surrounding it or other areas/states/cities etc. surrounding it. Houses already do this. This was maybe last year or so, but on the history channel there was something about solar panel houses and they produced more than enough electricity for themselves, they even sold electricity to the city which they generated from the solar panels. The panels were expensive, but the estimates were that within 15-20 they would be making money from it. So if you have a whole suburban area layered with solar panels and then skyscrapers, other buildings with them creating energy, a whole city could be run off just solar panels, or atleast 30-40%. Infact, some Los Angeles skyscrapers hinted at the idea a few years back and also some New York skyscrapers. Check out: http://www.ecmweb.com/mag/electric_photovoltaic_sy stems/index.html

Well, you could also have an automated cutoff for nonessential load (like 3 of 4 fluorescent lights or something). Or, you could use a battery UPS instead. But the flywheel is cooler...

random link

FWIW, I'm consistently quoted in real life print trade magazines. I can only find one article on the web (from 2002). Just do a search for my name (ADAM DADA) in the article for a little quote by me and a confirmation of my status as an IT specialist.

I generally don't defend my life, but the 2 e-mails I just received were violent enough that I felt a public post was necessary.