npts2020

You can boil water at room temperature but it takes a near perfect vacuum (around 1/50 of an atmosphere or less) to do so. IIRC the distilling units onboard ship operate at about 120º F at about 29.8" of mercury (close to pressure required to boil water at room temperature). The efficiency is not the biggest consideration because the option is to get a small amount of work out of the steam (distilling water) or just recondensing it and not getting anything out of it. The steam is around 500-600ºF (for a nuclear powered ship) to upwards of 1,000ºF for a 1200psi conventional ship, so you are already extracting the vast majority of the energy from the steam beforehand. Also, there is a fair amount of other equipment besides the main engines that are steam powered from catapults on an aircraft carrier to jet pumps for pumping bilges and more, so there is plenty of waste steam even if the main engines were 100% efficient (they aren't even close). The technology is substantially older than reverse osmosis 1860's vs late 1940's. The main problems with steam distillation are relatively high maintenance and high level of technical skill required to run them efficiently.

Nearly every ship in the US Navy makes fresh water exactly via this method. The equipment is called a flash evaporator (or distilling unit), most having several stages where the water is boiled, sent through a series of chevrons to separate water droplets out of the steam, recondensed and boiled again. A typical evaporator will have 3-8 stages and the water is VERY pure at the end of the process. Waste steam from the engineering plant is used to heat the water and vacuum is maintained by a combination of condensing steam and air ejectors (which work similar to a jet pump). Note, not all of the water is boiled off, the remaining "brine" is pumped away. Evaporators on a ship the size of an aircraft carrier are rated at 100,000 gallons per day and ones on something like a destroyer might make about 20,000 gallons per day. The Navy has entire week and two week long schools on their operation and maintenance. The reason these types of distilling units aren't more commonplace is that they are pretty expensive and require a fair amount of maintenance.

Until that time we could have a guaranteed basic income..... http://www.bbc.co.uk/news/business-25415501

And what makes you think that liberty or any of those other things are a "fundamental right bestowed by existence"?

If you have no fear in that situation (unlikely), you are still liberated, in my opinion. By the same reasoning, if I desire to jump to the moon but am unable to do so, does that mean I do not have liberty?

Liberty is having no fear.

To throw a wrench into the explanation, it depends on whether the steam is saturated or superheated. I can state with 100% certainty that you cannot see the steam from a 1200 psi boiler on a US Navy ship because it is superheated. When the main steam line gets a break in it, the safest way of finding it is by running a broom along the line until it either bursts into flame or is sheared off. You will not see the leak by looking with your eyes.

That temperature gap is what causes wind. There are many schemes for using wind to power something. Having said that, it is likely possible to use the temperature differences between say the Arctic and a tropical region but it would almost certainly be cost prohibitive because it would require some means of moving air on a global scale. Something like a wind tunnel could work but you are talking about building one a couple of thousand miles long (outrageously expensive) and not having a great deal of energy to extract when it is all said and done. There are probably other ways of doing such a thing but I can't imagine one that is going to give enough energy to make it worth the cost of construction when there are so many other ways of going about getting power.

I realize this thread has probably been abandoned by Wxman but if not, I would like to ask if there is EVER any level of human activity that could affect the climate? If so, where is that level of activity?

Sensei; Swansont beat me to it but would add that lasers are also used for tiny amounts of a substance so that one of the recent big breakthroughs has been cooling something the size of a microchip. Also, I get the impression that it is not a particularly efficient method of cooling but I couldn't find any stats about it from doing a cursory search.

In my opinion, peer review is still the best tool science has for vetting papers for factual content and arriving at the proper conclusions. The problem isn't peer review, it's applying it in a rigorous and unbiased enough fashion, like it wasn't in the above example. For now, at least, there is no substitute.

Trees don't grow fast enough, toxic waste doesn't break down fast enough, resources are too hard to get........etc. On the other hand it seems way better than any proven alternative.

Sure. How else are you going to get your RDA of all those good things? I wonder what the RDA for FD&C red #28 or titanium dioxide is?

Try this site for pretty current news. Realize that they are generating incredible amounts of data that will take time to sift through.

Two Voyager missions passed the outermost planets 20 years ago and are currently in the boundary layer between the solar system and "deep space".

They are delaying the 7 TeV collisions as I write this but are supposed to begin them within the hour. Done!!! Let the analysis begin.

How are you keeping the sodium from causing an explosion when reacting with the water? It seems to me it would be easier and safer to produce the hydrogen with your windmill sitting in one place and filling a tank in the vehicle with it.

Except that once you send it through a "pressure-decrease" valve, it takes energy to repressurize, in fact, more energy than you got out of the fluid to begin with.

lazygamer; Have you ever tried to cool something down to the temperatures required to have liquid nitrogen? It requires a *lot* of energy, way more than an air conditioner uses and if you understood how an air conditioner worked, you would see why it takes so much energy to cool something. I have never seen a process that will cool anything to the temperatures you are talking about that did not require major expenditures of energy, despite the "simple" process of only having to lose internal molecular energy. The system you are describing will require more energy to operate than you will ever get out of it.

So far I have only slogged through about half of the bill but it is my understanding that no future legislation is precluded by any of this bill. In fact, if I am not mistaken, a public option is one of the things that was to possibly be addressed at some future time.

Does that mean we ought to do away with the National Institutes of Health?

I am not exactly sure what you are asking but will try to give an answer. Photosynthesis is a biological process that seems to be pretty efficient, especially when compared to artificial photosynthesis.

Ibuprofen is definitely processed by the liver. Google "effect of ibuprofen on the liver" and you will find literally thousands of articles and studies about the negative effects of the drug on your liver.

Sometimes state records aren't even that good. The hospital I was born in burned to the ground about a decade later and there is no "official" record of the people born in that hospital. What is funny is that I have the original birth certificate (the one with the baby foot prints) but it is not considered to be a valid form of id.

I don't think we should change the calendar until we make contact with an alien sentient species. Until then we are living BC (before contact).