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Comment Re:Probably 15.0 kW, not 150 (Score 1) 106

You're all falling into the trap of average daily power usage. The heliostat needs to provide the peak power draw, not the average power draw of a house.

I'm a South African and while my 3 person house averages 700W power consumption over a 24 hour period, my peak is close to 10kW if I've got the stove, water heater and kettle going at the same time. That happens regularly in the early evening or mornings. And yes, we have electric stoves and water heaters because we don't have a gas infrastructure like Europe or North America.

Our electricity rates per kWh seem to be comparable to the US rates, 10 US cents to 14 US cents per kWh for my city's inclined tariffs. But solar installation costs are high, a 10kW installation with batteries to hold overnight can be around $25000 and the batteries will have to be replaced after 6-9 years at around $8000. My house uses roughly 1000 kWh a month for a bill of $110. So the capital cost would pay off over 19 years, but after a maximum of 9 years, I'd add another 6 years to that. And for the average working and middle class South African, $25000 as a capital expense is a harsh layout.

Comment Re:Cooling? (Score 1) 90

Even if you ignore the thermally conductive epoxies somebody else mentioned, simple.

Before you resin-pot the boards, you put a water-cooling heat exchanger on the chip and pipe the coolant to a radiator outside the epoxy block. Or if the thermal profile is low enough, you can do it with passive heat pipes like those inside my laptop.

Comment Re:FYI radio astronomers: Beware dodgy microwave o (Score 4, Interesting) 27

I've met a couple of the chaps working on the South African SKA site, very interesting characters to say the least.

One of the things that stuck in my mind was how sensitve the receivers are, if they unpack them and a cell phone is on in the direction of the receiver horn, they'll blow the circuits instantly.

They also have controlled perimeters where phones are locked away and even airplane transponders are switched off before they cross the perimeter. Ridiculously sensitive stuff.

Comment Re:Wait... What? (Score 1) 108

Given the lack, so far, of impact craters, the argument can be made that Pluto has cleared its orbit of other material and therefore does qualify as a planet under the IAU definition.

Looks like we get hit more often than Pluto does if the images released so far are representative of the rest of the surface.

Comment Re:Aren't they called Currents? (Score 3, Informative) 61

They are not currents because the water isn't flowing, it is moving in place, albeit a 500m range.

Waves in all definitions are movements within a fluid where the particles move back and forward around a fixed point. The dictionary definition is inaccurate by stating that the disturbance is at the surface, the movement happens through the body of water. It is visible at the surface, but it takes place in the body.

Comment Re:Single shop most likely (Score 1) 323

If you read the court filing, you'll discover that MS has identified the keys as being stolen from their supply chain and of being the wrong type of OEM key that a computer shop should be using.

And as for the publication of the IP address, that was declared in the court documents as required.

The very interesting factoid from this is how did people steal keys from MS's supply chain, especially non-issued license keys. Sounds like an inside job.

Comment Re:i don't understand the premise of the post (Score 1) 254

You can say that. But when you link another day to that date, as the idiot did by posting 4/16 on 4/28 and then state, "Just a warning", then there is a valid risk that you might be aware of, or planning, events like those that happened on 4/16 that will be enacted on 4/29.

And if the police ignored this because "free speech has no limits" and there was another attack, how much shit would they be in?

Comment Redstone (Score 5, Informative) 197

Well, it could be named after an obscure material in a computer game. An in-joke for those who know it.

Or it could be named after the Redstone Arsenal in Huntsville, or after the Redstone missile built there by von Braun and which was the base for Alan Shepard and Gus Grissom's flights into space.

Guess we'll never know.

Comment Re:I wonder (Score 1) 258

SA Breweries had a major issue with beer trucks going up steep hills in sections of South Africa. Some of these trucks end up going at walking pace and the people living in the areas would walk alongside, jump aboard and pass beer crates down. They solved it partially by sticking armed guards on the top of the truck during slow hill climbs.

"A complex system that works is invariably found to have evolved from a simple system that worked." -- John Gall, _Systemantics_