I see what you mean, but it's not the large body of water, per se, that gives more pressure at the bottom of the dam. It's the head, or the vertical distance between the turbine and the water level at the top of the lake. I'm not talking about putting turbines in a fast moving stream, either. The small hydro plant I'm talking about achieved this head by pulling the water out of the river and into an enclosed pipe a few miles upstream. The river had quite a bit of drop (several hundred feet) between the diversion and the plant. The pressure at the plant, minus some friction, would be the same as if they had erected a huge dam several hundred feet tall. Of course in this case it was MORE efficient, because the topology simply wouldn't have worked for a dam that big at that place.

Maybe you could argue it is less efficient because it didn't use ALL the water in the river. I think dams like Hoover dam are designed to do that most of the time. I guess they could have done that in the pipeline plant as well, if they had used a bigger pipe, but then they would have had the migratory fish issue.

Come to think of it, I HAVE seen another hydroelectric power plant of this type, right where Provo Canyon opens up into Utah Valley. There's a pipeline that runs along the canyon wall, and then there at the base it runs straight down into a small plant.

Not necessarily. Only if there is a big dam with a reservoir behind it. Hydro can be done without the dam, and it's just as efficient. It doesn't have the bonus of evening out the annual flow fluctuations, but it solves the flooding and migratory fish issues.

Close to where I grew up there was a small hydroelectric power plant of this type. Some water was diverted into a pipeline a few miles upstream. The pipe roughly followed the bank of the river, and the water gushed back into the river after turning the turbines at the actual power plant. The ecological effect on the river was less flow for a few miles.

I don't know why there aren't more of this type of power plant around.

In my experience this idea works very well. Get the siblings together and they can feed off each other and just cover lots of memories.

Or spouse, parents, best friends, old roommates, co-workers, or even classmates or cousins. Anyone who spent a lot of time with her or experienced things with her.

One of the things that is fun is they never remember the same experience the same. One of my brothers has a scar on his cheek. It happened in a car accident. But each of his older siblings had a story where they thought they were the one that caused his scar.

Another game that fits into the category of "Educational but you might not know it" was Starcon2. I was interacting with a young man once and I mentioned something about Enceladus. He stopped what he was doing, gave me a strange look, and asked "Do you play Starcon?" I was a bit confused and said, "No. That's one of the moons of Saturn." He was amazed. He thought someone had made up all the moons of the planets for a fictional game, where in reality they had used actual existing Astronomy facts for their game.

He had played the game quite a bit, and knew many of the moons of the planets in our solar system, as well as many stars and constellations, and he didn't even know they were real! He was learning real Science by accident.

The game doesn't concentrate on teaching you such things, but you need minerals on several of these moons to build up your spaceship. Then you need to travel to some constellations or named stars in order to make contact with different alien races.

I have thought about the huge amount of information that you learn playing games like World of Warcraft or Everquest. I played for several months, and learned vast amounts of information about History, Geography, Politics, even Science of a fictional place. That could have been more valuable if it had been even a little bit patterned after real places in the History of Earth. Imagine, instead of Crossing the continent of Antonica going through the pass of Highhold Keeep heading for Qeynos, if you could cross Europe going through the Alps heading for Shanghai. Or instead of raiding the Plane of Fear, if you could go visit Old Japan, or Medieval Europe, and actually talk to real historical figures and do actual historical quests. Do a quest for Hannibal that has to do with feeding his elephants. Do a quest for Maria Antoinette that has to do with eating cake in instead of bread. Instead of filling your brain with fictional people and events, you could be learning real History.

There are scenarios of Civ2 that have simulated real Earth maps with actual real cities on them. You can learn some real Geography very easily. And some History as well if they're set up that way. Something as simple as using Constantinople instead of Istanbul or Gaul instead of France teaches older versions of Geography.

There are some serious possibilities here.

Your energy calculations are WAY off.

>Trains still need energy to move and that means Diesel, which incidentally is pretty much similar to Kerosene.

Maybe. But in any case a LOT less. Do you have any idea how much jet fuel it takes to power a passenger plane on a single flight? A 747 uses 3378 gallons per hour! And that's cruising. It uses more during takeoff and climb. Of course it's traveling pretty fast, and carries a lot of people, but that can't make up for inherent issues of air travel. The wikipedia article on transportation fuel efficiencies puts average passenger air travel at 1.4 MJ/passenger-km. TGV gets .15 MJ/passenger-km. Combino light rail in Swizerland gets 0.085 MJ/passenger-km.

So we're talking an order of magnitude here. Maybe it will cost a lot to put the electric lines in, but the energy savings are substantial. And even if they don't choose to use electric power (an option not available to airlines, by the way) diesel is lower energy density and cheaper than jet fuel. Or they could use any of a bunch of options. Natural gas, hydrogen, even coal or nuclear.

>It's true the US expends the most energy per capita worldwide. But constructing rail infrastructure will raise, not lower that for at least two decades.

Or, we could use less energy. Every person that uses the rail saves the energy they would have used had they taken a plane or a car. And the maintenance energy that would have gone into those planes and cars. Every person that doesn't buy a car because they can use the rail saves the manufacturing energy. Frankly, I think laying train track and stretching power cable is easier and less energy intensive than manufacturing cars and gasoline.

And there are other savings. Pollution. Carbon footprint. Funding enemy regimes.

Rails are perfect targets for terrorists. You just muck up one little line of steel, and you can injure and kill lots of people. And you can do it out in the middle of nowhere, minutes or hours before the wreck is to take place, and have plenty of time to make your escape.

How long do you think this would go before a major incident would cause knee-jerk legislation? They would impose such ridiculous requirements as to make it totally impossible to make any money.

Which is really too bad, because trains are inherently way more efficient than any other mode of land transportation/shipping we have. If it were done right, it could bring the price of transportation and shipping way down, and the speed way up. And reduce the carbon footprint considerably at the same time. And reduce our dependence on foreign oil. And reduce air pollution in a big way. I would love to see this happen. But it won't.

The problems with rail in the United States are not technical issues. They are political issues. Railways have been HIGHLY regulated ever since they were recognized as possible sources of serious profit back in the 1800's. The laws they have to deal with and the rules from the unions and taxes and fines and such make it pretty much impossible to make any progress.

If Obama is able to create a new system that doesn't have all that political baggage, it just might work... until some disgruntled rail worker (or anarchist, or terrorist, or mercenary contracted by some big oil tycoon) decides to rip up a track. Then you'll have to arrive 3 hours early and take off your shoes...

Are you really interested in tying your shoes faster? A couple of years ago, I came across http://www.shoe-lacing.com/shoelace/ianknot.htm and was surprised that there could be so much analysis to what I thought was a simple concept.

Now I use Ian's knot most of the time when I tie my own shoes. If I REALLY want them to stay tied, or when I tie my son's shoes, I use Ian's secure knot. It takes a little longer to tie, but I've never had it come undone prematurely.

> and they are more energy efficient than CFLs.

See. now this is where I have a problem. This seems to be the general feeling, and is easy to believe, but whenever I run hard numbers, I get the opposite result. Even ignoring the cost of buying the lights, any believable data I can find and plug in indicates that CFLs are still significantly more efficient in terms of light output / energy input.

Granted there are a lot of different numbers people are putting out and arguments about whether you need to take into account lumens/watt or lux or recessed fixtures or whatnot. Sure you can find scenarios where the efficiency doesn't matter, but I still can't find any hard numbers that support your assertion that LEDs are more efficient. Can anyone find me some?

Novell can talk all they want about this, because they have already done it themselves. Not that it saves them all that much when buying new machines. The first thing I do when I get a new machine (complete with the Windows XP shiny colored license sticker on the case) is wipe the Microsoft OS off the hard drive and install Linux. However, they don't need to pay yearly license fees for most of their employees any more. That is a HUGE chunk for a company the size of Novell.