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Comment Re:Waste of helium (Score 2) 190

What is this "tremendous amount of extra mass" you are referring to? If we take Hindenburg(not -berg you millennials!) as an example, the solution, and the idea, would be just to replace gas contents of the space between hydrogen cells and the airship outer shell.

This is not increasing mass a lot since the only thing needed is to have a airtight and controlled outer shell where the pressure can be adjusted. Splitting the sections and adding pressure monitoring system would detect the outer shell ruptures immediately, adding time to react and repair damages if possible.

All this does not make the airship fire or accident proof but it would add one very good feature: a spark or a hot spot of heat inside the outer cell would not ignite the hydrogen cells, specially if instead of nitrogen we use helium as the "insulator" gas. Then there is no oxygen for any kind of fire. Any total puncture would result a hydrogen+helium leak. I don't know how they dilute but my guess is probably better than hydrogen and nitrogen.

Point here is that making the hydrogen relatively safe as a lifting gas it would make safe enough autonomous airships. Those can be used for transporting cargo and other tasks which do not need any personnel on board.

Of course it is possible just use hydrogen only and take all of the risks at once... but still I'd estimate that cargo shippers would like high payload and added safety.

Comment Re: Good solution (Score 1) 983

No-no-no, the big question here is that how the police force of Dallas, or any police force in any place in any country in the world at all, can have instant access to claymore mines?

This is the first time I have heard that police force ANYWHERE in the world has access to anti personnel mines. Protect and serve... with anti personnel mines? What? Seriously, USA, what the hell are you doing?

Comment FUD from Greens I suppose? (Score 1) 404

I guess the logic is this: "Hmm, I think people know modern diesel engines as well as nuclear power, so lets spin a story claiming that there is a huge pollution problem with the cruise ships". And so they did.

Meanwhile the Google-able people can google "Wärtsila 46F" and see this statement from the Finnish manufacturer (we Finns take environmental matters seriously too even though we also have a Green party advancing coal power):

"The technologically advanced Wärtsilä 46F can be run on either heavy fuel oil (HFO), marine diesel oil (MDO), or on light diesel when being operated within strict coastal or port emissions areas. This fuel switching can take place smoothly and without power interruption across all engine loads.

This flexibility enables the operator to select the fuel according to price, availability, and the need to meet local emissions regulations."

More fun facts: Port of Helsinki is going to receive record number of these large cruise ships this year, over 300. Since our summer is short the density is higher than in Southampton which has ~450 cruise ship visits per year. Is air pollution a problem here? No, like previously stated, cruise ships, ferries, all big ships, are able to switch to low polluting diesel when they are in port. And they do so. We have shore electricity support and waste water treatment. Actually we just completed legislation with other countries which forbids any waste water discharge in to Baltic Sea, that being sea-wide legislation of the entire area.

So, things are actually good in real life. It just seems that the Southamptonians(?) either have outdated port rules and equipment or they are victims of another "green" FUD scare.

Comment Re:Still (Score 3, Insightful) 286

LZ-129 (airship Hindenburg) surface area: 27,299 square meters. If upper half is covered with solar panels there would be ~4MW of power if we use current off the shelf 30% efficient solar panels. That power is actually more than the four 16 cylinder Daimler Benz diesels provided for that airship.

However when flying over water the reflected sunlight would provide energy too. It would be probably wiser to wrap the entire airship with solar panels. Remove diesel engine weight three times (one left for emergency backup) and reduce fuel volume to one quarter of the original amount of diesel. It might actually work during daytime. However I don't have any idea would even the lightest thin film solar panels be light and strong enough to replace current materials used as outer shells. Then there is the night cruising issue, there should be batteries or some other energy source for that.

If I recall correctly there are some solar powered airship projects where U.S. military is seeking a "all seeing eye" functionality, unmanned high altitude airship where solar power is the primary source of energy. Maybe something interesting spawns from there.

Comment Re:So what? (Score 2) 164

Yep I have been wondering the same thing. A lot of new things, "news for nerds", are happening on the nuclear industry, next generation designs are approved and soon built. 90's and 00's slashdot would have published those stories. I think eco-hipster coup happened at some time and now this is the new "green slashdot" where nuclear is evil, no matter what. What a pity.

Submission + - Why You May Not Like Ted Cruz's Face, According To Science (

An anonymous reader writes: Ted Cruz pitches himself as an overcomer, an underdog, an outsider who beats the odds. While the Republic candidate has won four states in this nomination race so far, a neurologist says he still faces a big obstacle with voters: his own face.

In an interview with Quartz, George Washington University's Richard E. Cytowic said the unusual movements of Cruz's face may make him seem less sincere to the human brain than other candidates. "The normal way a face moves is what's called the Duchenne smile, named after the 19th century French neurologist. So the mouth goes up, the eyes narrow and the eyes crinkle at the outside, forming crows feet," said Cytowic, a professor of neurology. "Cruz doesn't give a Duchenne smile. His mouth goes in a tight line across or else it curves down in an anti-Duchenne smile. So he doesn't come across as sincere at all."

Comment Re:Common sense (Score 3, Interesting) 229

7000GW of nuclear power is coming to Iran right now. Iran signed a deal with Rosatom, Busehr is going to have three more 1GW units and they are going to build four 1GW units to the coast of Caspian sea. It seems that "someone" noticed this, especially when you look through Google Earth. Busehr 2nd unit renovation started this autumn and suddenly there is a bi-monthly picture update on it.

However I am not saying that solar power is a flawed solution for Iran, on the contrary: Iran is also a good place for solar power, they can build CSPs easily and use solar panels too. Their energy mix is going to be very wide from traditional fossils fuels to renewables and nuclear power. Just too bad USA is not going to receive a cent from that market. Or actually not, you economy is already too good, we europoors need some new business opportunities. :)

Comment Energy consumption is going to increase (Score 1) 645

If the rest of the world will go to 1/3th of 1st world energy consumption we will need a lot of new power in near future. "Renewables" are not enough even if we focus everything on building them.

I quote Dr. Ripudaman Malhotra @ TEAC7: (

If we want to replace one cubic mile of oil by 2050 we need:

200 Three Gorges dam. One built quarterly. We have perhaps three (3) rivers left for such installations. So, no new big hydro. Small perhaps but I personally enjoy more of free flowing rivers than dam lakes.

2500 900MW nuclear plants. One built every week. Completely possible, no shortage of fuel with fast neutron reactors where the remaining 97% of nuclear fuel gets used.

7700 900MW consentrated solar parks 25% availability (10x size of Andasol CSP). 3 a week for next 50 years. This is possible but getting difficult.

3 000 000 1.65MW windmills 35% availability. 1200 per week for next 50 years. This is where it starts getting hard. We need 50 million tonnes of steel/year (possible) and lots of rare earths (not possible) for generators, transmission lines and electronics and billions of tons concrete for offshore installations. All of them are big carbon emitters. Low power density creates need for large power networks, transmissions losses reduce the efficiency of such system. Still I say go for it where the wind is constant, like trade wind regions.

4 200 000 000 (4.2 billion) solar roofs 2.2kw 20% availability. 250 000 new installations _every_ day till 2050. I am sorry, this is not possible. We don't have enough roofs at places where people can actually afford solar roofs and their lifetime, even if increased to 35 years, is not enough.

So this is why we must build 4th gen Uranium-Thorium reactors with passive safety systems. Reactors which operate at 700-800C and produce process heat. Then we can decarbonize things like concrete production and recycle municipal waste/biomass to liquid fuels etc.

These new plants are modular where every part except of the concrete can be swapped when it gets old or fails some way. Concrete is long lasting stuff. It is possible to get Colosseum like lifetimes for these installations, 2000 years easily. 4th gen reactors close the nuclear fuel cycle so the unusable radioactive byproducts are minimal and they have a short half life.

What is worrying me is that the projected energy consumption is nine CMO (all energy forms converted to oil) by 2050. We are using 3.5CMO now. So basically we have to build everything non-fossil source we can. This is possible with nuclear because that is the one which actually makes money to finance the other not-so efficient energy sources.

Comment Apples for Nukes? (Score 1) 61

Apple Inc. Eula: "..You also agree that you will not use these products for any purposes prohibited by United States law, including, without limitation, the development, design, manufacture or production of nuclear, missiles, or chemical or biological weapons."

However I am ok with this. These nuclear explosions should be classified as art nowadays. Just do the dirty math with Linux and everyone should be happy.

Comment Re:With a RTG, it couldn't have got to the comet. (Score 3, Informative) 523

It seems there are a LOT of people who think RTGs are similar to nuclear reactors. Their idea seems to be that the RTG is heavy because it must have gamma radiation shielding around it. This is not true. RTGs emit alpha rays and heat, no gamma ray shielding is needed which means RTGs are lighter than solar panels producing equal amount of heat and and electricity.

Comment Re:Occams Razor (Score 1) 112

Yep. If we ever find some chemical traces of life I bet we will not limit the sampling for one time only. A moon disturbance will be detected within days of the observation because the spectra will show significant changes when the moon changes its orbital position to the planet. TFA gives a bad feeling, do the "scientists" have some other agenda behind them?

Comment Lots of Civilizations, too much noise (Score 1) 608

My counter argument to the Fermi paradox is this: if there are hundreds, perhaps thousands of nice and peaceful civilizations who all like astronomy, and specially radio astronomy, then perhaps they have forged an agreement that lets keep quiet for long periods of time so that all participants can do meaningful exploration of new civilizations, like us. Maybe the time to advance our radio-space exploration and understanding of cosmos is very short so we will shut up too (radio silence), very soon.

Perhaps we should start investigating what would be the "Central Universe Time (CUT)" or, "Central Galaxy Time (CGT), because if such agreement would exist then the silence would be certainly broken at defined time intervals. Transmission times would be naturally determined by prime numbers and some exotic mathematics. :)


Comment Re:Propaganda Piece fudges truth . . . News at 11 (Score 1) 846

This was because the polar vortex was not in its normal position. No connection with global warming, it just happens from time to time. When the polar vortex is over Canada and USA they have the cold weather and the Atlantic winds keeps carrying humid and warm air over here.

This Xmas was not the warmest in record although it was warmer than most of the years. Finnish Polar Circle is only ~700km from the Atlantic and the same goes for rest of the Finland. Atlantic weather systems bring a lot of rain and mild weather here.

Now we have the "normal" Siberian high pressure system pushing cold air here, it is -15C in Helsinki, temperature in Lapland above Polar Circle is between -9 and -30C.

So, when you see extremely high variation from the average temperature it is definitely not the global warming, it is a weather system anomaly. Those are local, not global, and have happened since the beginning of the Earths atmosphere.

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