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Comment: Re:Comparing apples to miniature oranges (Score 1) 409 409

It's not clear to me that the cube law is applicable. The cube law comes into play when all three linear dimensions (height, width, and depth) are changing by the same factor, so you are assuming that a width and depth (or girth) increase proportional to height increase is all healthy weight.

While this may be true it's something that needs to be examined in more detail to see how healthy weight is a function of both girth and height.

Comment: Re:Reasons why I don't like Musk's hyper loop (Score 1) 124 124

by MattskEE (#49915697) Attached to: SpaceX Is Building a Hyperloop Test Track

Wow, you're nitpicking very specific features of a system that doesn't even exist in prototype form yet.

1. Windows will no doubt be added so long as it is mechanically sound and doesn't endanger the passengers, and so long as seeing the landscape at such high speed so close to the ground isn't disorienting.

2. I'm sure before any people travel on this system (for which there isn't yet even a prototype) a safety analysis will be performed to see if an auxiliary air supply is necessary. They may well add breathing masks similar to what airplanes have for the event of high altitude depressurization.

3. Just because there's no indication yet of multiple "lanes" yet doesn't meant that there won't be.

Comment: Re:those numbers? (Score 1) 259 259

The price of installed solar has dropped by half so new panels without the subsidy would have the same payback time. 8.8kW installed capacity at $3.46 per installed watt (as stated in the article) would now cost $30.4k.

While solar panels will not last forever they already pay back much more than their installation cost (even subsidy free) in much less time that you think. It is folly to compare the reliability of cell phones to solar panels.

You seem to just be looking for reasons to bash solar. Solar is not a silver bullet, there's no such thing yet. But it works and it's available now. And over the long term it more than pays for itself.

Comment: Re:Deceptive wording (Score 1) 259 259

Why so negative? This is a feel good article, and there's nothing wrong with that. It is pointing out quite rightly that solar has achieved a new milestone in adoption rate which is a good thing.

Yes it is well known that solar installed capacity does not correspond to generating capacity. And there is the problem of storing energy when intermittent renewable sources like solar become larger percentages of total capacity. But the solutions to these problems are available now if we choose to dedicate the resources.

Your numbers are also way off, solar has risen over 50% over the past year:

So yay. We went from half a percent to 0.51% total power input.
And oh darn. We maybe stayed around 20% at coal.

The correct numbers Source:
March 2014: Solar 0.4%, Coal 41%
March 2015: Solar 0.6%, Coal 33%

Most of the drop in coal usage came from the sharp uptick in natural gas. That same uptick is probably why solar outpaced coal. Solar is rising rapid though still very minimal, but accelerating the rate of install will get us to total renewable energy faster.

Comment: Re:Go Solar, it can make good financial sense. (Score 1) 259 259

The above article points out that the cost is now $3.46 per installed watt, he installed 8.8kW, so today the same installation would cost around $30.4k (his out of pocket cost 10 years ago).

In other words the subsidies accomplished their precise goal of helping to jump start a solar panel and solar installation industry which now gives a payback time in the above case of about 10 years.

Comment: Re:The Dark Age returns (Score 1) 479 479

The Big Bang Theory is a superb example of this. It's treated as absolute and indisputable fact, yet it was never (and likely never will be) directly observed.

That's quite incorrect. The Big Bang Theory is treated as the best explanation that we have, for now, for explaining a combination of observations. I'm not saying that all middle school teachers get this subtle but important point across in their science classes, but rest assured that the scientists themselves are familiar with it. And if a better explanation comes along that fits the data better than the big bang then scientists will eventually jump ship to the better theory.

Comment: Re:Darwin by proxy (Score 1) 616 616

by MattskEE (#49532325) Attached to: Bill To Require Vaccination of Children Advances In California

I don't understand why people who vaccinate are afraid of those that don't.

It's not fear, but there are several legitimate reasons to be concerned about people who choose not to vaccinate their children for personal non-medical reasons:

1) Some people have legitimate medical reasons why they cannot receive vaccines or it is harder for them to get vaccines, e.g. allergies.
2) Vaccines are not 100% effective but increasing vaccination rate provides greater protection to all.
3) We still care about kids who are not our own and we don't want them to catch easily preventable diseases like measles.

Comment: Re:Powdered alcohol is stupid. (Score 1) 421 421

by MattskEE (#49410429) Attached to: Powdered Alcohol Banned In Six States

Get yourself some 200 proof booze, put it in a flask, and if you want drink, then mix that with some amount of water because you really don't want to drink 200 proof booze straight unless you're completely crazy.

At least 15 states already ban 190 proof alcohol, in those states 150 proof is typically the maximum allowed by law.

Comment: Re:No they don't (Score 1) 226 226

by MattskEE (#49374113) Attached to: Chinese Scientists Plan Solar Power Station In Space

That does not change the fact that the math is pretty solid and it would work.

You haven't done the math or cited any.

There is a big efficiency problem in space-based solar with the double conversion from DC to RF/laser and back to DC. Total efficiency neglecting transmission loss is about 64% (80% twice). Then you have to invert it back to AC usually, but that is also needed for terrestrial solar.

So 35% power is thrown away, but since the sun is stronger in space without atmospheric attenuation, and there are no clouds, some of that will be made up.

So to a first approximation the power per unit of panel area is the same from space as it is on earth.

Now factor in launch costs which are tremendous (even if SpaceX succeeds in yet another 10x reduction in launch costs as claimed) and the difficulty performing maintenance in space versus on land, and I don't see a strong case. Installation costs on land are around $1/watt, I'd like to see you come within a factor of 10 of that in space.

FORTRAN rots the brain. -- John McQuillin