Ask Slashdot: Enterprise Bitcoin Mining For Go-Green Initiatives?
All laptop users are required to run on battery power throughout the day until 20% and then they plug in.
How is that green? As already pointed out, wear and tear will go up, consuming energy to manufacture and transport more batteries. Plus recharging the batteries will take *more* power to recharge them was discharged from them (due to efficiency lost in both the charging circuitry and the chemical processes involved. A quick google suggests at least a 10-15% hit).
Plus, most machines' default power profiles reduce performance when running on battery, so I wouldn't be surprised if things take longer to accomplish. i.e. Less work out of people, for the same overhead costs and environmental power usage (heat, lights, etc). [side note to pedants: any power savings from cpu throttling/spindown could be gained independent of battery usage by managing power settings, so it could still be accomplished where actually desired]
Unless running on battery is able to shift the consumption from daytime to seriously off-peak (past 7pm?), it's probably consuming more power....especially if everyone runs low and plugs in at the same time, or plugs in just before heading home and adds to the residential peak typical at quitting time.
Sounds like another bright PHB idea, like reducing heating in winter will save the company money......until they start to wonder why everyone types slower in gloves and makes more typos... :P
Blu-ray Update Sent To User Via Credit Card Records
Or he *returned/exchanged* a product purchased on his credit card to the store in the past and they asked him to fill out one of the return forms with name and address. Now BB has tied his address to his credit card, so he's now populated in the database with full name and address.
When he purchased the Blu-ray player, it used his credit card to lookup his record and put the purchase down on his record, even though he didn't supply his personal info at that time.
Then, when it comes time to mail out updates, they just lookup all transcations with the player, pull the purchaser info...bang.
Fakes, Coming to a Store Near You
NiMH batteries are generally pretty safe. They don't really require any onboard electronics, just a peak detecting charger if they're being fast-charged. If shorted, they may get *really* hot or ignite adjacent materials, but they're not as reactive as lithium based technology.
Li-Ion/Li-Poly cells are the dangerous ones. Basically they can reach a run-away condition very easily, and lithium is *very* reactive. They can ignite if punctured, charged too fast, over-charged, or if they drop below a certain voltage and are then charged at normal rates. They will also swell/burst if over-discharged or over-heated. Most Li-Poly/Li-Ion packs include a circuit with a thermal cutoff to prevent over-heating, a circuit to prevent shorting/excessive-discharge-rates, and a circuit that isolates the pack if it drops below a safe voltage (usually around 2.5-2.8 volts per cell).
I did purchase a pair of Li-poly batteries for a cell phone, which were no-name imports. They did not have any cutoff circuitry, and I suspect could have been nasty if they wandered out of spec (either through abuse or a defective phone). I used them with no problems though, but I think I'd reconsider, given what I know now about Lithium cells.
That said, the circuitry required for Lithium cells is becoming cheaper everyday (the functionality is avaiable in a single chip), so I wouldn't be surprised if "decent" third-party units do have the desired safety functionality.