How come a fuel cell functions as an inefficient battery? You need to produce the electricity, then you need to electrolyse water to get the hydrogen, then feed it through a fuel cell and drive an electric motor. I thought the fuel cell itself was highly efficient, and an electric motor is also more efficient than a combustion engine. I thought the biggest efficiency issues were in the generation and storage of hydrogen.

Rising food prices also provide the world with the opportunity to get rid of the subsidies. The EU spends half its budget on farmer subsidies. It also strengthens the position of rural communities in poorer countries, because their produce is worth more. It can help pay for much needed investment in irrigation and the like. There has been a long term fall in investment in farming in rural areas. The share of public spending going to agriculture in developing countries has fallen by half since 1980. [source: The Economist, Dec. 8th, 2007]. It's not all bad.

I agree that many of those "green" technologies are not so green in practice. Very often the problem is that manufacturers will offer what they can sell as "green" and not what really is.
It`s not all about the environment either, it`s nice to sometimes focus on the core function of a product and do that well, just for the shake of it.
You can have a green hydrogen car, or you can have this http://www.caterham.co.uk/.
A good example of a product that`s green just by sticking to it`s purpose without being distracted by hippies or marketing.
I also think that high resolution video is a perfectly meaningful achievement, it`s the current execution that bothers me, especially the two redundant standards (hd dvd & bd) and the two available resolutions (720 & 1080).

Please elaborate. There are batteries on the market today which have extremely fast recharge times. What is needed is the infrastructure to perform the charging if you want extended range. These batteries are also currently very expensive, but they are getting cheaper.


You are right, the biggest drawback of a hydrogen fuel cell is the inefficiencies of producing hydrogen, which currently either requires a lot of electricity or natural gas. While a fuel cell itself is currently much more efficient than an internal combustion engine (ICE), it still falls well short of current battery technology. Fuel cells are about half as efficient as using a plain old lead-acid battery.


Very true, which is why in Europe at least, the government closely regulates the term "green" in advertising.

At best, you can only compare "green" products to it's alternatives and as such, products can be classified as "greener" but rarely can you actually call them "green".


IMO, the Caterham is not green at all. I would bet that the vast majority of it's customers own the Caterham as a second (or third) vehicle. I also doubt that any of them are terribly fuel efficient, even though they use relatively small engines (and even though Caterham has produced some very fuel efficient prototypes).

At best, you could call a Caterham "greener" when comparing it to a Porsche, Ferrari or similar.

Fuel cells can be refueled faster than even the fastest battery, and they don't suffer from the significant recycling issues faced by batteries (batteries really don't last all that long). However, this is irrelevant, because you're mistaken in thinking battery-charging infrastructure is possible. - you underestimate the kind of energy you're actually putting into a car when you charge it. Charging overnight isn't a big deal, because you're running a small current for a long time. When you want to charge in ten minutes, though (to be competitive with liquid fueling times), things change. You have to put energy into the car 50 times as fast. For a 35-kW battery pack (capable of running a fairly standard car about 100 miles), a 10-minute refill will pull more than 200 kW through the charging system. The cabling running from the charger to the car will have to be an inch thick just to avoid bursting into flames, and what if multiple cars are filling at once? Your charging stations will have to be built in utility plant parking lots, just to run all the chargers at once.


Batteries currently have better efficiency than fuel cells, but that's not what matters. As long as the electricity used to create hydrogen or charge the batteries is produced cleanly (nuclear), the efficiency is barely even a consideration. For use in vehicles, what actually matters is energy density, or the amount of energy you can produce for a given weight of supply system. The better your energy density, the longer your range before refueling. By this measure, fuel cells absolutely demolish batteries, though neither currently beats petroleum (and won't, at least for a very, very long time).

Right. A tank-to-wheel efficiency of 45% is still not very much. I didn't know fuel cells themselves were so inefficient.



Right. A vehicle with no roof is not very well suited as an all-round vehicle.

I don't know what all this garbage about cars is doing in an HD thread, but I recently purchased a TV for the first time. I got married and my wife really wanted to have TV and cable and all that, so I figured I may as well go the whole 9 yards and I purchased a 1080p LCD display from CostCo along with signing up for cable TV service including their modest HD offering and a DVR. There's only a couple channels in 1080i, several more in 720p, and the rest are regular old standard TV signal.

IMHO, 1080i looks far better for mostly static shots than any of the others. You can see the difference between a sharp 1080i production and the 720p stuff that runs on the NatGeo HD channel. Where 1080i seems to have trouble is in horizontally panning shots, like panning a landscape. It seems to show a little more blurriness than the 720p programs on NG-HD under similar camera conditions. I still don’t have a BD player or anything due to the cost, but based on how good 1080i images look, I’m expecting a high quality 1080p transfer must look pretty darn good. I know that the 720p and 1080i stuff looks significantly better than my ordinary DVD’s, although to be fair my DVD player doesn’t upconvert, it’s just a standard player with component cables.

I have my son’s PC running through the TV as well with a DVI to HDMI cable, but unfortunately the onboard graphics doesn’t support any HD resolutions, so it’s just running 1024x768 right now. It looks like I’d have to spend at least $40 to get a card that will properly run 1366x768 and 1920x1080 out the DVI. Overall I’m very happy with the setup. It looks good, has lots of connections, and 1920x1080 is about as high resolution as I can picture wanting on a 47â€

Hrm... could we move this thread to Off Topic?

I completely agree with your first paragraph. Of course, it exactly matches what I previously wrote that you claim to be disagreeing with.


Your article is wrong on how 1080i is produced. Digital cameras do not "shoot" interlaced video. The video is shot at 30 fps at 1080 X 1920. Either in a second stage inside the camera or during the process that turns it into ATSC, each frame is turned into two 540 X 1920 fields. Now, 720p is shot a 60 fps. This is easy enough to do, since 60 X 720 X 1280 is actually less data than 30 X 1080 X 1920. Back in the day, there was a big argument about being allowed to broadcast in 720p since shooting at 60 fps is better for sports, yet post-processing 720p into 1080i was expensive. Of course, newer cameras can shoot 1080 X 1920 at 60 fps (which would allow your 1080i60 finished product to be exactly as good as 1080p60 on a set with a good deinterlacer), but professional HD video cameras are very expensive and those that invested in 1080i/720p equipment are loath to upgrade just to give you the home viewer a nicer picture for sports (especially thanks to exclusive broadcast rights). So chances are very high that any 1080i content you see was either shot at 1080p30 or 720p60 and then converted into 1080i60. However, this has nothing to do with whether it will look nicer on a 720p or 1080i set. That is all a function of the video processor inside the set, as we both agree.

Jesse,

I imagine you are correct. The article was so well written that I assumed that it was correct. All the information I ever saw in it was accurate with what I had already learned, and it presents the information in a nice graphical manner. Regardless of the complexities of how the video was shot, 1080i with the right processing is the superior format while 720p remains an excellent compromise to get around poor processing on 98% of the TVs out there.

And to get back on topic, HDTV is the next logical step in TV, though I wish they had stuck to a single resolution and cable to make things easier. The $200 HDMI cables are ruining HD for most as I find it comical when I see people with their $60 upscaling DVD player and their $70 HDMI cable. Those poor misguided people...

The reason the OP doesn't think HD is worth it, is because he watches way too many YouTube videos and his ipod is probably his only flatscreen.

1080p is only for those with huge screens. So yes 1080p is needed.

I find cables of all sorts are the things that brick and mortar stores mark up the most egregiously. Try and buy a 10-15' Cat5 cable for less than $15 at a typical electronics store. That same cable will be < $3 online! Same with HDMI/DVI, where what is $15 online will cost you $40 at Best Buy. Why can I buy a short USB cable for < $1 online, but many physical stores want $20!? Even factoring in shipping it is almost always cheaper to buy cables online. Next to extended warranties, the next biggest waste of money is often buying the cables at the same store you bought the TV. Let's not even touch the issue of Monster and other "premium" cables . . .

The worst part of this is that HDMI is digital. A few years ago with component and composite inputs, you needed high quality cables. Monster has always been overpriced, but they are still good cables. Now, though, everything is digital. You can use the cheapest cable you can find, and if it works at all it works perfectly. Digital signals are great like that.

Wrong again. I don't have an ipod and my only flatscreen is the 19"WS I'm now looking at, on which is it very nice watching dvds, thank you very much.

+
Perhaps you'd like to keep to the matter instead of ridiculizing the poster.

I agree that HD is just the next logical step. There seems to be nothing against it, but I still wonder if such investments are a good way to spend our resources, given the state of the world. For instance, do TVs get more expensive, or do LCDs now have about the same price level as CRTs in the days of old? Do we need more and more resources to enjoy our lives, or is it becoming less, because for instance LCDs use less material in terms of mass than CRTs, to get produced. I'm wondering about such things. But perhaps this is idle wondering...

Good to know that the €20 euro 10m DVI-HDMI cable I have in mind will do just fine. But perhaps I will just stick to the €3 svideo cable. What a difference! Are these normal prices? A "Professionele Component Video Kabel - lengte 10 meter" sells for €30.

It's the same in the Netherlands. I was once looking for an svideo cable of length 10m. The first shop I went to was talking about having to order it and it would cost around €30. The second shop didn't have one either but he sold me a composite+stereo cable for around €22 (corrected for inflation). These same cables now sell for less than €6 online.

Yeah I think I paid $16 for my 6' DVI to HDMI cable. Granted, it's video only, no audio signal, but one place online wanted $90 for the same cable, and I think it was NewEgg where I got essentially the same cable for $16.

I suppose it depends what you call big. Sharp make a 1080p Aquos that is only 32".

Yes, but 32" is exactly the case where, when used strictly as a TV, 1080p is unnecessary. From 6' away, most people would not be able to tell the difference between a 720 line screen and a 1080 line screen. Of course, many 32" flat panels are also used as computer monitors, where the extra resolution is much appreciated.

The thing that I find most disturbing about the whole HDTV conversion (here in the USA) is that it is being forced upon us. (By government prodded by industry). By comparison, the change from black and white to color was handled seamlessly. One could continue to use a black and white set, or get a color set. (We had a black and white set while I was growing up, when most folks had upgraded to color.) My parent's 25+ year old color TV (first color set we had) finally gave up the ghost.

Now we are in this tremendous wellfare program for industry where regular television broadcasts will no longer be available, and we have to buy some sort of converter box to go on receiving television. If this had been left as a market matter, there might have been incentive for manufacturers to make converters available and affordable.

Recently I have been forced to look at televisions, and I am inclined to concur with the OP.
Digital television appears to be in many cases worse than analog television. Certainly it is capable of highly detailed pictures, etc.
But for displaying existing media, it is often worse than analog television.
(Specifically aliasing artifacts.)

Our old television did not have the resolution, true. But it also did not have all the jaggies/ posterization/ halos /etc. that one sees with digital broadcasts. (It may be possible to minimize those with careful processing, but how often do we get careful processing, versus something that is just jammed together quick).

Even things that are intended for HDTV often have these effects. So yes, it may be capable of great things, but in the common way it winds up being worse than the older systems because it makes such faults more noticeable.

One (minor) upside of the conversion - I suspect my parents will wind up with a second-hand CRT, which can be had for very little.

(In response to one of the observations in the thread - higher resolution is not always better. In many cases in a digital system, lower resolution with a greater number of digitization steps may provide better reproductions because of aliasing.)

Re:


So, given the speed of our expansion into space, how soon can we expect to see the first billion moving off earth (or sufficient resources coming from extra-terrestrial sources to sustain a billion people)?
We can expect another 3+ billion or more here earth in next 45 years.
How soon will space absorb or provide resources for any reasonable proportion of that increase?

Recently the population of the USA passed 300 million, in 1950, it was about half that.
Since 1950, the world population has grown by about 4 billion
(about 2.5x as many people now as at opening of the space era).

The lovely irony being that I'm going to be looking for a 1080p 27-32" tv next year. And yes I plan on using it as something where I'll only be 4-5 feet away...ala secondary computer monitor + movie watching. Resolution really matters at that point...currently I can see every dot in the 720p 27" I own.

It sounds like you think this is being driven by the TV and media industries, which is false. The shutdown of analog broadcasts is being prompted by the FCC, because analog broadcasts require many times the bandwidth of digital ones, and there are few things in this world worth more money and radio frequency spectra. The bandwidth currently occupied by TV signals will be free for some other purpose.

I can't really argue with your other points, but I thought it would make you feel better to know that the switch to digital is being done for legitimate reasons which may ultimately benefit everybody.

I don't have much experience with digital myself, as most of the stores naturally try to give you the best image possible. There was one instance, however, in which there was also an old low quality source which looked like it might have been VHS, and this video looked absolutely horrible on that large 1080p or 720p screen. It was more like watching patterns of big pixel blocks moving across the screen, than the content itself. I think it would have looked decent on a CRT.

So you would maintain that the TV manufacturers and consumer electronics industry did not push for this? Certainly they are not the only ones standing to benefit (I focused on them in my earlier post because that part seemed most relevant to the thread). It would be difficult to argue that the changeover isn't giving them more business.



I was aware of the intended redisposition of the spectrum. Whether it is prompted by the FCC, or by those who wish to make a packet by using this spectrum for their own ends is perhaps debatable, and a moot point. Given the way the government has handled the hand-out of other valuable public resources recently, the prospect does bode well.

When the TV broadcast spectrum was initially doled out there were proposals that had much better provision of public good (which somehow never came to pass). Small instances of abuse - the inclusion of shopping channels under public access.

More recently, look at cellular phones. Here we have an industry straight from the days of the robber barons. They make obscene profits, they ride rough-shod over customers (routinely sighted as the number one industry for customer dissatisfaction, etc). If the cell phone spectrum were managed more for the public good it could make a more reasonable return to the public purse (either in terms of more affordable use, or in terms of revenue to public coffers).

To bring it back a little more to green computing - consider phone handsets. Phone handsets generate a large amount of e-waste. Since they are bundled with the service, it is often not possible to keep a handset when changing carriers. Since they give you a new handset with renewed service, people take the new handset and toss out the old. (What is the point of reduce/recycle/reuse if you are going to be paying for a new handset - whether you use it or not.)

Requiring carriers to open their networks and prohibiting locking of handsets, would help reduce e-waste. Likewise requiring those offering subsidized handsets, etc. in return for long term accounts to make prominent offer cash (or credit) alternative of equal value would help reduce waste. So you can get the new "hoozy-watzit" phone free with your 2 year subscription, or you can get the retail value of the phone in cash, or you can get that much credit to your account.

Given the well-known abuses of public trust exhibited by industry and the government in handling the cell phone spectrum among other things, the prospect of another valuable public resource being put up for ravage by the highest bidder does not warm my heart. (Please do not take this as an anti-government rant. It is more that in these days of "deregulation" etc that the government is over-responsive to interests of business, wealthy and short-term profit, at the expense of the individual and sustainability.)



Exactly - my comments in previous post were partly partly from looking at digital broadcast signal of an SDTV program (just some random TV show rerun). But even the promotional material used by some of the stores shows similar problems. I was careful to stand back at a reasonable viewing distance, and still the digital artifacts draw attention like a stubbed toe.

Dunno if I'm off the off-topic here, but I have a 24" (1920x1200) and have obviously tries watching 1080p movies with this. So far I think I'm leaning towards 720p as I don't see a difference worth twice the file size between 720 and 1080p videos. On proper home theaters, on the other hand, I can see the point of 1080p. 720p projector (Sanyo PLV-Z3) image can't really be stretched to 100".

About the consumer-lifestyle in total; I try to think carefully what I'm buying and not waste money to get stuff that I don't really need. Might have something to do with my parents being annoyingly green

Watch the Story of Stuff.

I can certainly understand 1080p being overkill on a 24" monitor, no doubt. Mine is a 47" panel, so that gives it a lot more square inches of space to cover. Since my living room isn't very large, you end up maybe 8 feet from the screen. It's close enough that I can make out the difference between 720P on NatGeoHD and Mojo or HD Theater's 1080i programs, although they are still both pretty good and a BIG step up from all the 480 programs, especially old VHS tapes and stuff like that.

Still, 1080 will likely be as high-def as anyone will really care about for at least a decade. I suspect the 2560x1600 displays will be the next big jump, since they offer 2x as many pixels as 1920x1080. By then, LCD panels will be half or a third of the thickness, making 60-70 inch displays light enough to move around with just 2 people, and thus large enough to be able to discern the higher resolutions.

I don't know about you, but I can certainly tell the difference between 720p and 1080p on a 24". At that size, you can still size close to the monitor and almost see every pixel...especially at 720p.

Going back to OP's question...

The larger your screen, the more resolution you'll need. Period.

I just got a new 24" widescreen (1920x1200). My previous monitor was a 1280x1024 19" standard. I set the pixel ratio to 1:1, and I spent the evening enjoying my games at 1920x1200 resolution. Then at night I fired up a standard def'n DVD last night hoping to enjoy my brand new widescreen. Instead I was shocked by how, well, BAD it looked when I maximized the video.

When I expanded that same DVD to fill the screen on a 19" standard def'n monitor -- bear in mind the DVD is 2.35:1 widescreen whereas my 24" is 16:10 and my 19" was 4:3, so the expansion ratio on a standard screen is much, much less -- it looked pretty damn good. That same DVD stretched across a 24" widescreen monitor was abysmal. Features were blurry, faces looked a little smeared. I'd hate to think what it'd look like on a 50" TV.

Granted, you'd be sitting much further back for a 50" TV. But it all basically comes down to how many pixels are in a given area of your visual field. And as screens get larger and larger, you'll either need to sit farther and farther back (which kinda defeats the purpose of a big screen) or else increase the resolution. Otherwise the pixel size (pitch, I believe it's called?) will grow to unacceptable sizes.

I'm sure there'll be some sort of ceiling. When the screen gets large enough to fill an entire wall, I think whatever resolution adequately fills that up will be the limit

DVD is not only low res, also the bitrate is not very high and the codec (MPEG-2) is inferior to more modern codecs.

For me 1080p is huge. DVD to 1080p x264 has been for me a bigger leap than from VHS to DVD.

Yes well that seems to be a pretty (the) definite answer.

Pretty amazing though that something that looks perfect on a small monitor would look so bad on a large one. Perhaps that's also a drawback of LCD techonology as compared to CRT. DVD stems from the CRT era, but there were certainlty TV's bigger than 24".

Yeah, the LCDs are too exact. With CRT and its built in "blur filter" we were fine. With a LCD you'll have to squint to get the desired effect.

It's like how 128kbps MP3 sounds ok (or at least no different than the source) on a pair of $5 passive computer speakers, but when you hook up the thing to your decent sound system that is no longer the case.

Well, watching sports in HD, there is no going back. The NCAA and NFL in HD, you see so much more of the game.

I just bought a 46 inch Samsung 1080p LCD. It replaced a 14 year old interlaced TV someone gave us 4 years ago after we got married.

We generally watch the HD stations before we look to standard def ones. The Xbox 360 gaming is fantastic. It upscales DVD's and they look quite good.

I just don't feel that most people see the need to go Blu Ray. First, is cost. A DVD player can be had for less then $100, Blu Ray players are still very expensive. Also, the media itself is cheaper, you can get a new DVD usually for $15 vs $24 for a Blu Ray.

Second, I think upscaled DVDs are good enough for most people. While Blu Ray certainly has a better picture, that is not the big selling point to people apparently.

Third, I think downloads are going to be relevant very soon, eliminating the need for optical. Yes, we like the feeling of physically having the movie, but an on demand system that you can watch anything you want whenever you want AT A FAIR PRICE, would put the nail in the coffin of Blu Ray.