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Comment Oops! it's a birthday paradox (Score 1) 142

The chances of anyone in particular having a doppleganger may or may not be one in 137, depending on how you define it, but the chance of there being dopplegangers is about 100%.

To oversimplify a bit, there could be millions of them in fact, because there's billions of people, and EACH of them have a 1 in 137 chance of having a doppleganger.



So it doesn't sound like their software is very good.

Comment Re:Canada gets screwed by the AGW scam (Score 2) 327

> Any "externalities" you might imagine have long since been paid for through the scientific and manufacturing technology that fossil fuels have enabled.

So, you're saying that (for example) the tens of thousands of people that die each year, in say, the UK alone, from largely invisible air pollution, much of which is due to burning fossil fuels, has been 'paid for'???

Sorry, no, you just pegged my bullshit meter.

Comment Re:I would like a simpler electric car (Score 1) 243

It's not that you can't take it past 80%, it's just that the battery lasts longer if you keep it at 80%; you just tell the car to do that, and it will stop charging when it hits 80%. Thing is, an 80% charge is MORE than enough for most people's daily driving.

The odd time you want 100%, you can just tell the car to charge up to full the night before.

Fast chargers also shorten the battery's life; but it's like 10% less. So the battery might last 9 years instead of 10 if you ONLY charge on fast chargers; but if you occasionally use the fast chargers, it makes no significant difference to the lifespan of the batteries.

And if you've forgotten to charge up? You just stick it on charger and wait for a little while until you have enough charge to reach the fast charger, then drive there and charge it for half an hour or so- whatever is necessary, and then go from there. It's inconvenient if you fuck up like that, but you're not going to be doubling your travel time, Tesla's charge faster than they discharge as they drive.

Comment Re:This was already known in 86 (Score 1) 133

You're full of shit. Iodine is just the most awkward fallout for nuclear power proponents only because it's the most obvious form of fallout in its effects. But both caesium 137 and strontium 90 are pretty bad things to absorb; they continue to decay in the body and cause cancer; and they're particularly bad for children because they're more sensitive to radionuclides and because they have longer lifespans in which to develop cancers.

And yes, the natural rate of cancer is much higher; but so what? Cancer is about the most common disease of all; but that doesn't mean we want MORE people to die of it.

Nuclear power is antiquated 20th century tech; modern renewables are cheaper, more flexible, cleaner and economically far safer.

Comment Re:Hydogen is just a way to store energy (Score 1) 630

The way this hydrogen stuff seems to work best is in a PHEV; in other words, a plug-in prius-like car that runs on hydrogen. It's got a relatively small fuel cell, and you plug it in at night to charge up a small battery that can go a few tens of miles.

Most of the time you run only on the battery; and that's fine for everyday use.

But for long distance, you turn on the fuel cell and it keeps the battery topped up as you drive around. Producing the hydrogen isn't very efficient, but you're only using it for a small percentage of your travel, and you're using spare solar energy that you couldn't otherwise use.

AFAIK the effective energy mass density for hydrogen storage now seems to comfortably exceed lithium ion batteries; so for long distances hydrogen makes sense. Also the embrittlement issue is not a problem if the materials are chosen appropriately.

There's still problems with the lifespan of the fuel cells; but again you'd only be using it as a range-extender, so it's not used a lot. Fuel cells are somewhat expensive for the power they produce, but using them as a range extender, you don't need a huge amount of power, most of that comes from the battery; that greatly reduces costs.

The systems are still expensive, but getting cheaper, and there's infrastructure issues; but they're not as bad as electric cars were, since the filling stations can be further apart, also hydrogen makers for home use are unlikely to be super expensive for slow filling overnight.

Personally I don't like PHEVs much, but the hydrogen PHEVs seem to be borderline doable now, they're actually in production.

Comment Re:We've got to get off fossil fuels faster (Score 1) 70

> A large part, as much as 80%, should be nuclear.

On most grids, it's a surprisingly bad idea to have that much nuclear in the mix.

The reason is demand-side variation; if you have to reduce the output of your reactor, the cost of the energy has gone up- for example a nuclear reactor running at half power is making electricity at twice the cost/kWh; and it wasn't cheap electricity to start with; nuclear power is never cheap.

With 80% you'd pretty much always have to daily be turning down your nukes due to demand side reductions. France has problems with that, they have some hydroelectricity to help buffer their nuclear, but not enough of the right sort.

Comment Re:We've got to get off fossil fuels faster (Score 1) 70

> I also believe that we are close to hitting the limits on wind and solar as well, if we have not already.

Not really. The limiting factors are almost exclusively financial, and costs are continuing to drop as production ramps up.

> I have been following the development of PV solar for some time now and while we see many claims of more efficient PV cells they rarely or never make it to market because of cost.

The PV market is not limited much at all by efficiency thing; most panels are 15-20% efficient but a 5% efficient PV might well be worth it if it was cheap enough to deploy.

> What I've seen as a trend in PV development is a focus on making them cheaper rather than more efficient. They'll give up as much as 1/2 of the power output per area if it means making them 1/4 the price. They'll just make up the difference in volume.


> Oh, and windmills are windmills. I don't see a whole lot of gains there either. The best we'll see is an improvement in price due to volume. People have been experimenting with windmills for centuries now, I don't expect to see big gains here.

Actually, this isn't true, there's been big improvements over the last decade or so, and there are quite big gains still being made even now. There are large gains being made in the last few years by making taller and taller windmills; the power is more reliable at higher altitudes that these taller structures can reach, and the cost per watt goes down-wind power is now the cheapest of all power where the biggest wind turbines are deployed. Also other big economies of scale are happening thoughout the production and installation processes. And replacing existing windmills with bigger windmills is a thing that is done where appropriate.

In short, there's no limits that have been reached on the cost/watt of renewables, which is mostly what we care about; energy efficiency is not an issue for renewables, unlike coal where you're actually having to dig coal out of the ground and where burning it creates pollution.

Comment Re:This was already known in 86 (Score 1) 133

"Nobody needed to worry except those near Chernobyl or any children in the areas where significant I-131 could accumulate."

Perhaps technically true, except that due to the weather conditions at the time fucking Chernobyl dumped significant quantities of I-131 in Wales, which was over 2000 km away.

That just shows how unsafe nuclear power really is. The Welsh farming restrictions took decades to be removed.

Nuclear power is unsafe in an economic sense, and it's not really safe in a medical sense either; just because you can nearly always get away from a nuclear disaster before it kills you (and hence leads to few deaths) it doesn't mean that it's safe, any more than fire is "safe" if it burns down a building if everyone gets out. If it was really safe you wouldn't need to have everything contained in thick steel and concrete, and it wouldn't fairly regularly melt down.

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