Solar Collection Not Such a Big Pane....

[Ursa major]

This looks like a relatively simple way to increase solar cell productivity:

BBC NEWS | Technology | Solar dyes give a guiding light

[BookStop]

Good ole MIT does it again.

[Perpetual Man]

Very interesting. Perhaps another small step closer to a nice clean science fiction future

[chrispenycate]

A cheat.
A good cheat, and well worth doing, but it's not increasing the efficiency of the conversion any, only increasing the surface area which is collecting energy.
And it's only adapted for electricity generation, none of the higher efficiency uses of direct solar energy (mostly involving heating things)

And it doesn't help the real problem; storing the energy for use when needed. Perhaps good for a solar-powered air conditioner, though.

[Ursa major]

Originally Posted by chrispenycate

Perhaps good for a solar-powered air conditioner, though.

And why not: I'm sure I've read that some parts of the US spend far more on air conditioning than heating over a twelve month period.

[Dave]

In the 1970's my father was a salesman for Scotch Tint. You must have seen Scotch Tint before. It was invented by Gerald Berger while he was with 3M's industrial tape division in 1966. All those big shiny glass skyscrapers had it, and it effectively blocks 99% of the sun's ultraviolet rays, and about 79% of the heat.

It probably still is used, but I don't see Scotch Tint used anywhere like as much today, probably because it really looks naff from inside the building, especially when it starts to peel off the windows. This idea is fine, but I think this will suffer from the same problems - a tatty and cut-price image, and a more long term loss of dye from the windows.

My father has had an interesting career, he was also a salesman for Velvetex in the 1970's. That was a wall covering made from coating of fibres sprayed onto a resin painted on a wall. That didn't really catch on either. I think there were some health and safety issues with the fibres, and some problems with the speed the resin set. I really don't know as I was too young, but one trial was it's use as the hair on Action Man heads. I had Punk Action Men with purple and orange hair before Punk Rock had even been invented.

[Nik]

Possibly this stuff could be used to retro-fit double glazing and solar-thermal panels. Getting 'juice' from the panels, reducing heat-load on rooms, reducing sound penetration...

Um, technology may mature in time to replace current crop of double glazing in 15~~20 years...

[TheEndIsNigh]

Sadly the carbon footprint in replacing all those frames would wreak any advantages in old building. Still new build may have a chance though there would be a massive cable loom to hide and deal with which may make it too painful.

[Nik]

What, TEIN, you don't have your accessible windows wired for alarms ??

Seriously, a 'massive' cable loom is not necessary if you only want the juice to tickle your wireless widgets' eponymous wall-warts...

D'uh, I've got five (5) 6-way power strips under this desk, 5 vacant slots and only three of those accessible due wall-warts' overhangs...

I'm seriously considering a 12-Volt supply system for router, NAS boxes etc...

[Wiglaf]

Well now that with the electricity shortage and enraged citizens complaints they have finally rescinded the moratorium on looking at requests for permits to build renewable energy plants, I am not sure that we need to be sneaky about it and hide them in our windows. However, as tinted double-glazed glass is the standard in new construction, adding solar energy generation to them to power the lighting control system (dimmers, timers, light and motion sensors) that are required by law and to reduce draw on the grid at peak times* would probably be the next step.
* Ursa is right. Heating is done by natural gas as it is cheaper and more efficient than heating with electricity produced by burning natural gas. Peak demand is at midafternoon on weekdays during the warm months, July-September. We have avoided roving blackouts for the last few years but we have no excess capacity to spare. We are maxed-out.

[TheEndIsNigh]

Nik: Well first for old building. If you were to remove the glass, you know that very high carbon footprint material, just to replace it with more glass the comparison of carbon saved to carbon wasted I suspect would be negative.

For new build that replacement cost doesn't occur however the problem is that with the best will in the world the chances of the electronics and wiring required in the frame lasting twenty years is fairly low. If only from a fire safety point of view these devices would need to be inspected regularly (remember annual PAT testing etc those all cost carbon) Even assuming that the voltage produced will be required in 20 years. If you selected 24V there's no guarantee that voltage would be common in 20 years. This would mean either replacing the electronics, the window or both. OK you could add gadgets that step down the volts but now your adding carbon footprint to use a carbon saving device. The windows would have easily lasted for over 100 years. If the window needs to open that just adds to the problems. Even given all these unaccounted for extras this development has, the devices you are going to power aren't that numerous. OK suppose we could all have personal air conditioning plants on our desk. Now that's a device that costs in carbon which certainly will not last for the lifetime of the window will need to be disposed of and will be extremely inefficient compared to the building wide versions. WiFi device and the like are quite possibly a fad and wouldn't be any use at all if the energy crisis develops to the stage where the casual use of electricity becomes questionable.

[chrispenycate]

Steel is inherently large carbon footprint, concrete enormous. Both of these are unavoidable, to do with the substances themselves. Glass takes energy, but does not involve much carbon. If that energy were available from alternative sources (Fusion power? Tide power, if you can organise a batch process) glass is pretty good, and very recyclable.
Furthermore, it equires fairly frequent replacement anyway, so windows do not require major structural work to change.

Voltage and current modifications are cheap, efficient and widely available. Stepping up the twelve or twenty-four volts from your cells to 110 or 220 volts is child's play nowadays (though getting it to 50/60 Hertz rather than 100kHz ± is a little more complicated, it could be done)
Why should distributed heat pumps be less efficient than massive ones? Along with giving individual control over climate conditions (the argument for hotel room units; you can cool or not, assuming you can do something else with the energy while you're not cooling) and you don't have to transport huge quantities of cold air from the cooling plant to the individual spaces.

Somebody who sits behind his computer, even on wifi, is using less energy than if he drove his car to the cinema, and even the electronic projectors there are using a fraction of the energy of the carbon arcs of my youth. Even going out for a walk, he is generating carbon dioxide - organisms aren't all that efficient, either.

Electronics and communications technology, while not energy neutral by any means, have made a lot of carbon wasteful physical displacement inessential.
Now, to convince ehe still increasing population of airline passengers that virtual reality is every bit as good…

[BookStop]

Originally Posted by chrispenycate

Somebody who sits behind his computer, even on wifi, is using less energy than if he drove his car to the cinema, and even the electronic projectors there are using a fraction of the energy of the carbon arcs of my youth. Even going out for a walk, he is generating carbon dioxide - organisms aren't all that efficient, either.

Electronics and communications technology, while not energy neutral by any means, have made a lot of carbon wasteful physical displacement inessential.
Now, to convince ehe still increasing population of airline passengers that virtual reality is every bit as good…

Validation at last!

[TheEndIsNigh]

hi Chris: Glass recycling is a pain to the manufacturers. They loose control on product quality and material consistency. They also need a higher temperature to burn of the impurities or they have to clean the recycled raw product to avoid this. The temperature and energy required to melt glass or sand isn't that much greater. The only reason they recycle glass is because there is legislation saying they have to. We don't even need to discuss the energy used in transporting it back to the few glass manufacturers available to do it. Whereas there is always a local dump and the truck is going there anyway.

I have posted this before in another thread but here goes.:-
I once followed a large (20+ tons) truck eight miles down a side road off the German autobahn system. It stopped at a small shop in a village and the driver got out and placed 2 small crates of empty bottles on the truck. He then turned round and went the eight miles back to the Autobahn to come off at the next exit etc. Now he didn't deliver any replacements he only collected the empties. That presumably is what he does everyday a complete waste of energy and carbon. But hey the Germans have excellent recycling figures there're the best but at what 'cost'.

I have seen the waste product due to recycling in glass factories and they really do mean recycled. As for replacing the glass in the first place I have a houses in my area where the windows are 100 years old (1905) they still allow the light in and will do for the next 100 years. No electronic gadgets to go wrong no wiring to replace.

Energy conversion techniques do exist though efficiency is appalling to go up to 250 Volts and then invert it to 50 Hz would not only be an expensive piece of kit on every windowsill but also give the very heat we would be removing in it's use.

So on the one hand we have a window. On the other we have a glass coated with a dye that will enable a solar panel to convert light into power which we will feed to a device that converts this power for use in some device.

We don't know the footprint of the dye or it's environmental impact or the cost of the plant to manufacture it. The solar panel is not free again we don't know the footprint or the environmental costs of this process. The device will also have its impact on the environment and all these extras will have an expected lifetime in years certainly not decades as is the case with the glass on it's own. Lets leave windows to do what they are good at letting in light and leave the gadgets bells and whistle to pollute the world in there own right. That way when the fad wears of we will still have the window doing what it always does.

[Wiglaf]

I'm thinking that it could become a requirement on new construction or on remodels where the exterior glass is replaced. You have to put in double-pane windows anyway and what solar you don't use is bought by the power company in the form of a deduction on your bill so why not? Here they are tightening up building codes for conservation not only because of global warming but because with the lack of infrastructure and resources we are expected to exceed our water and electricity capacity within a few years. With the return of roving blackouts looming, water prices expected to triple this year, and the resevoirs that supply water to Southern California, Nevada, and Arizona projected to run dry by 2012, they have been regularly looking at the Uniform Building Code for changes that could increase conservation.