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Painting The World's Roofs White Could Slow Climate Change

caffeineboy White roofs decrease A/C load!! (712 comments)

White roofs have the double effect of significantly reducing the air conditioning load within the building. This reduction in power consumption will probably reduce global warming by avoiding CO2 emissions as much if not more than the direct reflection effect... The peak power demand days in California are during the summer because of all the air conditioning.

One study found that there was between a 15% and 60% reduction in cooling power use just by applying a white roofing compound.

One problem with this is that high albeido (white-ish) pavement doesn't stay that way for very long because concrete ages and gets dirty.
You can read more about this here.

more than 5 years ago

Green GT's All-Electric Supercar Unveiled

caffeineboy Re:24 hour charge?? (196 comments)

This is how it was done in SAE formula lightning.

There is a video of the WVU team doing a pit practice here. These are college kids, probably engineers and not mechanics. A real pit crew could do it in much less time.

more than 5 years ago

New Data Center Will Heat Homes In London

caffeineboy Re:Heat!=power (204 comments)

If this is heat rejected from a server farm, it'll be too low grade to do much with it other than heating. You might be able to heat the premise hot water a tiny bit...

Absorption chillers, the common way to do waste heat to cooling, want medium grade waste heat a lot hotter than what's coming from a server farm and steam generation is totally out of the question.

more than 5 years ago

New Data Center Will Heat Homes In London

caffeineboy Heat!=power (204 comments)

As with anything written by a reporter, engineering details are all f'ed up.

"The project is expected to produce up to nine megawatts of power for the local community."

No, the project will probably pipe 9MW of heat from the server farm over to the housing complex. Hopefully they can use 9MW of heat continuously, summer and winter.

âoeThe energy savings will equate to boiling 3,000 kettles continuously,â

Um - that's a really funny way of thinking about saving energy. 9Mw/3000= 3kw/kettle. That's a hell of a kettle.

For anyone who thinks that running a computer in their house to heat it is clever, you would do a lot better (price AND CO2 wise) just running a furnace or your heat pump. Resistance heating is the WORST way to heat a house.

If you're going to be producing the heat anyway and can find a use for it like this, please do! Don't think that because you CAN use a computer for a heater means that it makes sense.

more than 5 years ago

Diebold Election Audit Logs Defective

caffeineboy Re:Fraud (256 comments)


more than 5 years ago

Fuel-Cell Car Racing Series Aims To Spur Green Motoring

caffeineboy Re:Not pompous enough (254 comments)

Not sure where you got the 50~60k battery replacement, because it's simply not true

The state of charge of the battery in a prius is carefully kept between 45% and 75% in order to give the battery pack a long life. And by long I mean that the prius taxis used up in Vancouver with 200k+ miles on the clock still haven't failed a pack.

The only packs that have failed in service are those that have been damaged in accidents or those that have been tampered with by "tuners".

more than 6 years ago


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