dye sensitised thin film

[MdB]

but PLASTIC istead of silicon??

Currently, a plastic base is very much more "green" than a silicon base as an awfully large amount of energy goes into making and purifying the silicon. As most of our energy is currently generated from non renewables, a plastic base is far better.

The same thing applies to plastic bags / paper bags in supermarkets. It takes less oil to make a plastic bag than it does a paper bag due to the energy use in the manufacturing process so the plastic bag is currently "greener".

Once our energy supply is significantly produced by renewable sources this result changes.

 

[Nemesis]

The same thing applies to plastic bags / paper bags in supermarkets. It takes less oil to make a plastic bag than it does a paper bag due to the energy use in the manufacturing process so the plastic bag is currently "greener".

Not very green though when it come to an afterlife!

Those sort of costs need to be added on.

 

[MdB]

Not very green though when it come to an afterlife!

Those sort of costs need to be added on.

Absolutely though putting figures on some of these things is difficult.

Far too many carrier bags get manufactured annually and putting a compulsory price on them (like I think has been done in Ireland) to encourage reuse sounds like a very good idea.

The total environmental cost of an item was on the news a couple of days ago when they were talking about English tomatoes vs Spanish tomatoes and Dutch flowers vs Kenyan flowers. In both cases the items that travelled the furthest were argued to be the more environmentally friendly due to the total amount of energy used in their production. Interestingly, the comment was made that more energy was used to move them around the UK than was used in getting them from Spain / Kenya.

 

[Nemesis]

I note that T***o has recently introduced a new re-usable bag. Two sizes, the larger is 40 p not sure about the smaller. Has pockets inside for bottles.

I appreciate that there are probably 'greener' alternatives, I have no idea how 'green' these were to manufacture, nor indeed how easy recyling will be, but these are substantial items that with care should last a long time. Each time one is used T***o credits the shopper with a penny or some such too.

Hopefully, these will mean far fewer 'disposable' plastic carrier bags are used.

 

[Flyfisher]

The total environmental cost of an item was on the news a couple of days ago when they were talking about English tomatoes vs Spanish tomatoes and Dutch flowers vs Kenyan flowers.

I saw that report as well, which was generally to do with the lobbying to remove the 'organic' labelling of foodstuffs transported by air from abroad. An interesting statistic was that UK tomatoes require about 4x the energy of Spanish tomatoes due to their being grown in heated greenhouses. So much for 'food miles' as an accurate measure of 'carbon footprint'.

 

[biffvernon]

Being a Cambridge "alumnus", as they call us these days (grumpy-old-man hat on), I recently got the alumni e-bulletin they send out with lots of good-news links about the University's achievements. One of the news stories was this:
http://www.admin.cam.ac.uk:80/news/dp/2007100501

That's a rather odd 'news' item from Cambridge. Thin film solar technology is well advanced with large scale production facilities coming on stream in the USA, China, Germany and elsewhere. It will be a serious competitor for silicon wafer in the years to come.

Whether this leads to lower prices is another matter. There is enormous demand for solar panels. The price will probably stay high as the constraint on supply will be the speed at which new factories can be built and the people to run them trained. The price of enrergy, of all sorts, will remain closely linked to the price of oil for many years yet. And that means it can only go upwards.

 

[Penners]

Can integrated circuits also be printed on to plastic film instead of silicon? I'm thinking of computer processors and so on.

 

[MdB]

Can integrated circuits also be printed on to plastic film instead of silicon? I'm thinking of computer processors and so on.

Flexible circuit boards have been around for ages which are basically plastic with copper etched / electroformed onto them.

They normally don't have components directly fixed to them but I believe it is possible.

Transistors printed directly onto plastic is also possible:

This plastic substrate contains some 2,400 organic transistors, each about 1/4 millimeter long and as wide as a human hair.

But I don't know of any application which has made it out of the lab and into production.

 

[Mark]

I read of a scheme where (in the future) excess PV energy would be sent through a world wide grid from areas in sunlight to areas that were dark and as the world turned, would reverse. Possible in theory, I suppose. It's pretty sunny in Saudi Arabia, they could farm out PV electricity instead of oil. So much for energy independence.

There are large electricity pipes being built. Lots of fuss at the moment about the ligne TNT which will take power from French nuclear poer stations in the North all the way to spain. Keep an eye out for the Non-TNT signs as you drive through Normandy/Britany.

 

[biffvernon]

This side of La Manche we find cables work better than pipes for electricity.

 

[Penners]

The name TNT suggests to me that the electricity is going to be delivered to Spain by lorry. That's actually probably easier than delivering it down a pipe.

Besides which, I believe that piped electricity tends to leak out if you leave a socket switched on without a plug in it.

 

[alice]

Besides which, I believe that piped electricity tends to leak out if you leave a socket switched on without a plug in it.

I found that out the hard way when I tried to mop up an electric leak without a proper earthing system. Now I make sure all of my sockets are well plugged.