Dinorwig was built to compliment the UK's intended nuclear capacity and smooth out the peaks. In part it was pushed up the agenda a bit by the OPEC induced acute oil crisis of the 1970's and the "Save It" campaign.
UK apparently has 472MW of battery backup capacity at present according to the report on the grid failure. It doesn't say how many MWhr though.
-- Regards, Martin Brown
Well now we know the sequence:
piglet
It might (or might not) be significant that the reported loss of generated power from Hornsea and Little Barford was 1.378 GW. That's just above the threshold required to activate a flux capacitor and initiate time travel.
(Damn- I screwed up the attribution. Anyway...)
Strontium-90 is dangerous because it replaces calcium in vivo.
Calcium aluminate is used in Portland cement replacements. Does it do the same thing? I haven't noticed many sidewalks glowing at dusk...
Mark L. Fergerson
This is a compound of ordinary natural non-radioactive strontium with amazing ability to absorb photons and re-emit them later. It makes the old glow in the dark toys look like - well toys. If I leave my find in the dark torch in the sun it will allow you to see by it after dark once dark adapted without having to switch it on!
It is very specific to a rare earth doped strontium aluminate.
-- Regards, Martin Brown
A modest sheet of that stuff could be left outdoors in sunlight, in some village without electricity. It would immuminate the indoors for hours after dark, enough probably for a kid to read a schoolbook by.
It must be 200x better than the old zinc sulfide stuff.
This glows in the dark, for a minute or so.
P7 radar phosphor.
-_summary_-_final.pdf
Maybe that's why initial reports of the cause of Little Barford dropping ou t and the timing were all inaccurate. The time line hadn't sorted things o ut and restabilized yet. Once the time travel event was properly integrate d with the power levels, all was well.
-- Rick C. ---- Get 1,000 miles of free Supercharging ---- Tesla referral code - https://ts.la/richard11209
That or a T1000 arriving. What is clear though is that the report's executive summary widely reported in the media is wilfully misleading. Let us hope that the technical report is not so compromised.
-- Regards, Martin Brown
I only mentioned that because of the very similar chemistry of strontium and calcium. Calcium is however considerably cheaper than strontium.
Okay...
I was just wondering if they'd even tried similarly doped calcium aluminate. Hell, do you know what it's doped with, and how much? I haven't done any experimental garage chemistry in a while...
Mark L. Fergerson
Calcium aluminate doesn't play or they would use it instead.
Dopant is usually Europium (and/or other REEs). See
You can buy the powder on eBay. 3M used to make a very good plastic using the stuff and a dayglo yellow marker pen dye to down convert blue photons into the peak band for human vision. It is more than an order of magnitude brighter than old zinc sulphide phosphorescent materials and much longer lasting (mine literally lasts all night in summer ~6 hours).
The snag with 3Ms product was that most people didn't understand the advantage of having an emergency torch you could find in pitch darkness. Modern mains supplies are so reliable people have forgotten the dark!
-- Regards, Martin Brown
An good LED is visible in the dark at 1 uA or less. An amp-hour of battery computes to...
I have some emergency lanterns that blink an LED in the dark without much affecting battery life.
A Tadiran lithium battery and an LED and a 1M or so resistor will be visible for 40 years or so.
Lithium batteries make most "energy harvesting" idea look silly.
Even at 10uA which is what I tend to run them at (previous generation) they still last a very long time. But the 3M product was back when LEDs were indicators and torches used 3v filament bulbs at 1A or so.
I still think that the 3M glo-plastic has a place in remote locations where charging a battery or the price of one is prohibitive.
-- Regards, Martin Brown
I took a good green LED up to the cabin where it's really dark at night. I got up at 2AM and ran a little test. The threshold of visibility was about 1 nA. I didn't expect that an LED would emit any photons at 1 nA, much less that I could see them.
Maybe I'll try that again, with the super-good Osrams of various colors. The blue is blinding at 5 mA, even though human vision peaks in the green.
It is surprising just how good the human eye is at detecting photons once it is fully dark adapted. Big cats are better. At 10uA even with the previous generation you can see to walk around once dark adapted.
I have a resistor with a 1970's era red LED and a modern high brightness one in series for science lectures. Startling difference! I am gradually running out of 1970's era ones - you can make their brightness improve enormously by dipping in LN2 to stiffen the crystal lattice and enhance the QE. They can only stand a few dozen or so cycles of this treatment. Latest generation high power LEDs the surface brightness of the die surface is approaching that of the suns photosphere!
-- Regards, Martin Brown
We used to run the old Cree blue LEDs at 50 mA, from a couple of
7438's in parallel. As they got better, customers started complaining.Blue led's tend to be annoying for some reason.
Also people carry emergency light sources in their pockets. My cellphone has an OLED display one one side and a high power LED on the other.
-- When I tried casting out nines I made a hash of it.
Indeed. Although before the invention of smartphones that wasn't the case. 3M were very unlucky that power white LEDs came along soon after their rather nicely engineered emergency dayglo torch was launched.
It was interesting to see people using them in anger during the recent UK powercut when emergency lighting in some London tube stations failed to work (probably due to cuts to non-essential maintenance budgets).
I am surprised that modern LED torches don't bridge their switch with a
10M resistor. It doesn't affect battery life significantly and it makes the thing so much easier to find in total darkness.-- Regards, Martin Brown
the good ones have a switching powersupply before the LED, but yeah the cheapies that run form 4.5 or 6V could be modified to glow in the dark. I have a bicycle light that operates from 6V and glows a little when the soft power switch is off.
-- When I tried casting out nines I made a hash of it.
Why on earth would you add a switching power supply to drive a handful of uA into an LED? The switcher would use more power than the LED!
-- Rick C. ---+ Get 1,000 miles of free Supercharging ---+ Tesla referral code - https://ts.la/richard11209
The switcher is there to put hundereds of mA through the led from a
1.5V supply.-- When I tried casting out nines I made a hash of it.
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