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Comment Re:There must be a very good reason... (Score 1) 579

A utility's peak power demands are typically from 3pm-6pm A solar customer is likely selling power back to the utility during this time (or at very least, using less than they would have), so the utility's peak requirements should certainly be less.

A solar power user's peak output is from 9am-3pm. By the time the utility's peak period hits, the solar users have already begun to dwindle in output, and many will be drawing off the grid. By the time the peak period ends, solar users aren't generating much at all, and will be pulling nearly all their power off the grid. That's completely ignoring the fact that you can have cloudy days where solar users do nothing. Installed solar capacity on the grid does not change the amount of peak capacity a utility must have available. Capital investment is a significant percentage of the cost of electricity, so the less you use installed capacity, the less you have to amortize the cost over, and the more expensive the energy it produces becomes.

This energy would need to be stored, but it's still energy that they don't need to generate themselves. With plug-in electric vehicles replacing gasoline, I don't think there's much danger of solar customers ever generating too much energy.

Yes, the energy would need to be stored, which means a secondary storage system in your home. Batteries are expensive. If they weren't, utilities would be throwing them all over the place to absorb the power from base load plants and completely replace peak plants. Even if you're using gas turbines for base load, rotating machinery that never stops is much more reliable than rotating machinery that is frequently cycled.

Most of those plug-in cars are going to be driven to work, and off site for the entire useful duration of a home solar installation, unavailable to operate as that storage system.

Comment Re: There must be a very good reason... (Score 1) 579

They also have to bump up your power from 110/220V to residential transmission voltage, and then deal with the phase imbalance because you're only feeding single phase. They're also doing it in mid-day, when the motel is largely empty besides cleaning staff, and really has very little power consumption to speak of.

Comment Re:No, entirely bad (Score 0) 579

we still have no workable solution for waste disposal

Of course we do. Stop making so much waste.

Of the fuel we use in reactors, roughly 3-4% is actually burned. Another few percent is transmuted into waste. There's still over 90% of perfectly good stuff left in the spent pellets. If we just use breeder reactors (which we've had since the dawn of the atomic age) and do nothing else, we're immediately looking at several times the amount of fuel burned, and thus several times less waste mass produced per unit energy.

Now of that waste mass, discounting the remaining U-238 that could be recycled as fuel, only a few percent is dangerous enough to need long term storage, and would still remain in any significant quantity after a few decades of decay. Only that few percent would have to be disposed of, either through geological storage, transmutation to something less hazardous, or discarding out of our gravity well. If the government needs to subsidize something, they can bring back their waste reprocessing subsidies that Carter banned, and Reagan never reinstated.

Comment Re:The 780 pound? (Score 1) 90

This is a US based website. People in the US understand pounds of weight. They typically do not understand kilograms, and definitely do not understand slugs, of mass. Using pounds is the most sensible way to report it.

In reference to the Earth at that altitude, it weighs around 700lbs. Space is not a "weightless environment". You cannot make such statements without specifying first that you're operating off the local space station reference frame.

Comment Re:Why not just push the old one down to Earth (Score 1) 90

Actually, atmospheric drag will finish the job. The ISS needs to get regular boosts, around once per month, to maintain altitude. It uses around seven tons of propellant each year for orbit maintenance. Now granted, this pump will be considerably denser than the ISS as a whole, and thus would descend slower, but re-entry would occur in under a decade.

Comment Re:Worth it. (Score 1) 123

Races and deadlocks are just really difficult to reason about. There are very few people in the world who can reason about them effectively.

We get around that stuff by simply not having them. With no mutexes, you have no deadlocks, and the code is designed such that we don't care about race conditions. It's actually multi-process, rather than multi-threaded, due to a legacy holdover from older versions of QNX that didn't have a threading model. If one process gets to a data point before another process that edits it, we don't care, we'll just pick up the change in the next pass. If that data point changes twice before we get back to it, we don't care, as the transient nature meant the change wasn't important anyway. If the change was important, then we either run the process more frequently to catch those changes, or have a latching flag to indicate a change took place.

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I have hardly ever known a mathematician who was capable of reasoning. -- Plato

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