The Stall of Technology

[TR]

TR I assume you are talking about batteries? it's just as canis said some technology progresses fast others slow. Batteries are very much in the slow bracket. Batteries have changed very little since the lead acid versions. You talk of small mobile ones yet the battery life is still shit, most of the extra life is from more efficient screens etc.

Really? The energy density of batteries has increased by an order of magnitude over the last two decades, and will in all likelihood continue to grow more in the future. Without this advance electric powered cars (beyond golf carts) would be completely unviable due to weight constraints.

At the same time recharge rates have been going down at a spectacular rate.

Hydrogen seems like an easy simply way of transporting potential energy.

I don't see the unstable argument being relevant. Its just a design process to make the storage safe. Petrol isn't exactly a safe liquid yet we are all happy to drive very fast with a big tank full of the stuff, because the tanks are 'safe'

Hydrogen also comes with a lot of disadvantages. A lot of these are similar to the current disadvantages of LPG, including:
* Low energy per volume means the need for a very large tank.
* The tank needs to be kept under high pressure, meaning increased risk in a collision
* Extremely flammable (much more so than petrol, not to speak of diesel)

On top of that come:
* Not very efficient to produce.
* Cost of transport

I am not saying that hydrogen won't make it as a technology. However, with the advancements being made in battery technology it is far from obvious to me that it will be the only game in town. We may will see that for urban traffic, batteries stay the energy carrier of choice.

 

[TR]

I might have mentioned this before but I believe liquified air could be an excellent power source. Imagine you put solar panles up in countries in the Middle East and use the electricity generated to compress and liquify air. Once the air is liquid it can then be shipped, in a similar way to liquified petroleum gas currently is.

Once you get it to where you want to use it you can expand the air back to a gas and use it to run turbines to generate electricity, in the same way power stations currently use steam. I'm not sure whether you could use it to power a car, maybe to run turbines to generate electricity for motors.

How does this compare to other methods of transporting that energy in terms of efficiency?
e.g.
*running a high voltage powerline from the Sahara to here?
*Using the electricity to make hydrogen from water and use that in a hydrogen cell at the point of use?

 

[FB]

Here's a link to help explain things far better than I can: Liquid Air Energy Storage (LAES) | Energy Storage Association

And here's a company doing it: Highview Power

This is what they are doing in Norway, a country which has an excess of electricity and, I believe, does burn fossil fuels in any large amounts for electricity production.

 

[TR]

From that link, it appears the technology is mainly used for recycling "waste" energy excesses. In such a situation any energy you can store for later use is profit, hence the actually efficiency of this may be fairly low. There is also no talk of transporting energy in this form. This suggest that the energy store per unit volume and/or unit mass is probably not particularly high.

The main advantage of this type of technology seems to be that it has a quick response time, hence its is ideal for levelling out peaks and dips in electricity supply/demand. It is therefore great as a supplement to wind and solar energy production (which does not necessarily peak at the same time as demand).

 

[FB]

Haven't had a chance to look at this in any detail but the Institute of Mechanical Engineers has set up a working group to look at this: The Liquid Air Energy Network :: Home

 

[FB]

Following on from that I found information about the Dearman engine which uses liquid nitrogen.

Sainbury are trialing this on the cooling systems of their refrigerated trucks. Looks pretty cool but I'm not sure how efficient it is.

Home

 

[Speshal]

I've always maintained that the stall in technology has been down to the limiting factors around current battery technology.

Lo and behold, just yesterday I read an article about how a researcher was dicking around in the lab one day (technical terminology non withstanding) and discovered that if they coated gold nanofilaments in a gel instead of a liquid a n battery could withstand 200,000-300,000 charging cycles with no loss of performance compared to the current (no pun intended) battery life of around 3000-5000 charging cycles. Couple that with an advance in grapheme battery technology that can charge a battery from flat to full in seconds then we may well see great leaps forward fairly soon.

I shall edit this when I can find the link.

*Edited - link

Researchers Accidentally Make Batteries Last 400 Times Longer

 

[Bill Boddy]

Ah, gold batteries for the rich, nickel ones for the poor.

 

[Speshal]

Ah, gold batteries for the rich, nickel ones for the poor.

Ah, I thought someone might have noticed that, however, you'll only ever need one of them.

 

[Titch]

Is liquified air something like water ?

 

[FB]

It's air that's super cooled to -196C Titch so that it's a liquid.

 

[Greenlantern101]

Can we talk about scram jets, or rather the lack of them.

 

[Titch]

If you like Greenlantern101 , whatever floats your boat.

What IS a scram jet ?

 

[Greenlantern101]

Well the theory has been around for decades yet we still have feck all in reality.
Basically it is a jet engine that works at extreme speeds. Specifically in excess of mach 4.5
The main problem with extreme speed jet / scram / ram engines is the air flow literally blows the flame out. Scram jets slow the air before burning, allowing 'extreme' speed flying .

When I say extreme I mean it. The air friction literally melts the airplane if you get it wrong.

X-planes in the 70's reach mach 3 with 'rocket power'
X-43a in 2004 was the first 'thrust producing' scramjet super sonic aircraft, it reached scram jet speed using rockets then enganged the scramjet. and accelerated 'away' from the rocket acheiving 6.8 mach. (concrorde did mach 2)

The X43b, x43 c and x43d are so top secret there is only projections and speculation. Is is thought the x43d exists and can get to mach 15. But who knows. at that speed a plane could circle the globe in just over 3 and a half hours.

It's clearly beyond complex, current thinking is an engine that can 'change configuration'. Normal jet to mach 2.5 ram jet to 4.5 then scram jet to speeds beyond.

Rocket scientists are pussies. Scram jets scientists are the real deal.

1970-2016 still not mainstream.

 

[Bill Boddy]

Are they practical for going out to buy the groceries?

 

[FB]

Maybe...

 

[Bill Boddy]

And just where do I sit? It's normally next to the driver.

 

[Ojir Mc Kenny]

Toyota are putting a Hydrogen car into production. Link.

old link, but it does help alot for newbie

 

[gethinceri]

Damn, thought this thread was a link to a shop.

 

[McZiderRed]

It was, but it was one of those links which disappears when you want it. You know, like those local corner shops that promises to provide a cheap link to a handy well-known brand for years, but disappears when you need it. Bastards...