Lion Kuntz
25th January 2007, 04:49
I know this forum is designed for, and populated by, people who are dealing with home-sized power issues, but Rob did post a greeting message when I signed up that posting message traffic can help him achieve his goal of getting 500 members into the forum.
I am always on the hunt for information and ideas for alternate power suitable for large projects, multi-story buildings with 100 living units, and downstairs public or commercial space. Your challenges are multiplied by a lot trying to crack this nut.
Now, I hope this isn't too far off-thread or off-topic, but I would like some review of possibilities.
First things first. I am pushing an idea, and my website has had 800,000 hits over 4 years, which started out from the assumption that BIPV (Building-Integrated PV) would be sufficient and affordable. Since I was starting from a blank piece of paper going into areas I didn't know if anybody had ever entered before me, there wasn't anywhere to go to get data handed on a silver platter.
I knew from long decades of experience that terraced buildings allow several roof deck layers to get light as patio decks, and that sloped shoulder buildings gave a smaller shadow profile onto neighbor's solar right-of-way then box shaped buildings.
I think we can all agree that it is un-neighborly to shade your neighbor's solar panels or even their building if you can design better.
42
I used some 3-D ray tracing software to make pictures of what the sun would do on these kind of buildings. I liked the results I saw. I expanded the concept further and further.
Ultimately I got way over my head, personally. Design of multi-megawatt 24-hour power supplies is nothing I had any real background for.
Now, four years into this, I think I know what has to happen.
Basically, PV must be incorporated into the building like never before in history, to the point that PV is actually created in the building as part of the whole utilities services of power, heat, cooling and cooking gas with H2-PV, meaning PV power stored as hydrogen for non-sun-production hours.
Conceptually it's easy: plug a PV bank module into a reversible fuel cell module, and voila! In reality there are all kinds of sticky technical details.
The sticky details are in the Balance of System, more than anywhere else, so that's why I picked this forum section to post.
I think the kind of issues involved could make for an interesting discussion going over months, but that's just what I think, and depends heavily on other people thinking so too.
The basic parameters of the problem are outlined in some sample chapers of an uncompleted e-book. See http://ecocity.us for details.
The typical city block that I paced off in several cities was around 2.5 acres, or the international land area unit of the hectare (10,000 square meters). Of course there are more blocks that vary from that idea, especial in subdivisions that favor cul-de-sacs, so that it's really nothing more than a starting place to begin thinking about it. If the people didn't object to shaded roofed-over outdoor patio decks, the theoretical maximum PV power from polycrystal comes out to 1.3 megawatts per peak sunny hour. In the sunny southwest people might prefer shaded decks, and they get 6 full peak hours without tracking.
As you can imagine, this is not your backyard DIY installation.
Is this anything people want to talk about in their spare time?
If it's not right for here, this forum, Rob will say so, but I have a couple of new forums that I just started where we could move it in that case.
The optimistic numbers are not achievable for several reasons, but even half that much energy, say 650 kilowatts/peakhour is still heavy duty to think about. It is more than enough to make PV through the Electromagnetic Casting furnace process. An EMC furnace process 30 kilograms of silicon per hour (best state-of-the-art) and uses 12 kW/kg for 360 kWhs per hour. It would take 67 days for one of those furnaces to cast the polycrystal silicon to roof the building. (Yes, I know there is more to it than just that.) :cool:
Still, think about it. One building makes an essential part of the PV in two months to equip a similar building. If the building shell was built and the power systems installed while the interiors were being finished out, the building could devote almost every watt of power to the PV operation before the people moved in. By the time the building was populated the PV system would have paid off it's debt for it's own initial PV system by producing PV grade polycrystal ingots of marketable value. The two months, or 67 days, was predicated on non-storage of energy. With storage and 24 hour operations the casting of 10,000 meters of PV grade net silicon is 17 days.
Rummaging around I came upon some expired patents that show a pathway this can happen:
* 4588571 - Filed Apr 19, 1984 - Heliotronic Forschungs-und Entwicklungsgesellschaft fur Solarzellen- Grundstoffe mbH - Process for the purification of silicon by the action of an acid
* 4457903 - Filed Mar 1, 1983 - Heliotronic Forshungs und Entwicklungsgesellschaft fur Solarzellen Grundstoffe mbH - Semicontinuous process for the production of pure silicon
* 4572812 - Method and apparatus for casting conductive and semiconductive materials
There is a ton of Balance-of-System issues before anything real could happen, but these are starting places to talk it out.
I am always on the hunt for information and ideas for alternate power suitable for large projects, multi-story buildings with 100 living units, and downstairs public or commercial space. Your challenges are multiplied by a lot trying to crack this nut.
Now, I hope this isn't too far off-thread or off-topic, but I would like some review of possibilities.
First things first. I am pushing an idea, and my website has had 800,000 hits over 4 years, which started out from the assumption that BIPV (Building-Integrated PV) would be sufficient and affordable. Since I was starting from a blank piece of paper going into areas I didn't know if anybody had ever entered before me, there wasn't anywhere to go to get data handed on a silver platter.
I knew from long decades of experience that terraced buildings allow several roof deck layers to get light as patio decks, and that sloped shoulder buildings gave a smaller shadow profile onto neighbor's solar right-of-way then box shaped buildings.
I think we can all agree that it is un-neighborly to shade your neighbor's solar panels or even their building if you can design better.
42
I used some 3-D ray tracing software to make pictures of what the sun would do on these kind of buildings. I liked the results I saw. I expanded the concept further and further.
Ultimately I got way over my head, personally. Design of multi-megawatt 24-hour power supplies is nothing I had any real background for.
Now, four years into this, I think I know what has to happen.
Basically, PV must be incorporated into the building like never before in history, to the point that PV is actually created in the building as part of the whole utilities services of power, heat, cooling and cooking gas with H2-PV, meaning PV power stored as hydrogen for non-sun-production hours.
Conceptually it's easy: plug a PV bank module into a reversible fuel cell module, and voila! In reality there are all kinds of sticky technical details.
The sticky details are in the Balance of System, more than anywhere else, so that's why I picked this forum section to post.
I think the kind of issues involved could make for an interesting discussion going over months, but that's just what I think, and depends heavily on other people thinking so too.
The basic parameters of the problem are outlined in some sample chapers of an uncompleted e-book. See http://ecocity.us for details.
The typical city block that I paced off in several cities was around 2.5 acres, or the international land area unit of the hectare (10,000 square meters). Of course there are more blocks that vary from that idea, especial in subdivisions that favor cul-de-sacs, so that it's really nothing more than a starting place to begin thinking about it. If the people didn't object to shaded roofed-over outdoor patio decks, the theoretical maximum PV power from polycrystal comes out to 1.3 megawatts per peak sunny hour. In the sunny southwest people might prefer shaded decks, and they get 6 full peak hours without tracking.
As you can imagine, this is not your backyard DIY installation.
Is this anything people want to talk about in their spare time?
If it's not right for here, this forum, Rob will say so, but I have a couple of new forums that I just started where we could move it in that case.
The optimistic numbers are not achievable for several reasons, but even half that much energy, say 650 kilowatts/peakhour is still heavy duty to think about. It is more than enough to make PV through the Electromagnetic Casting furnace process. An EMC furnace process 30 kilograms of silicon per hour (best state-of-the-art) and uses 12 kW/kg for 360 kWhs per hour. It would take 67 days for one of those furnaces to cast the polycrystal silicon to roof the building. (Yes, I know there is more to it than just that.) :cool:
Still, think about it. One building makes an essential part of the PV in two months to equip a similar building. If the building shell was built and the power systems installed while the interiors were being finished out, the building could devote almost every watt of power to the PV operation before the people moved in. By the time the building was populated the PV system would have paid off it's debt for it's own initial PV system by producing PV grade polycrystal ingots of marketable value. The two months, or 67 days, was predicated on non-storage of energy. With storage and 24 hour operations the casting of 10,000 meters of PV grade net silicon is 17 days.
Rummaging around I came upon some expired patents that show a pathway this can happen:
* 4588571 - Filed Apr 19, 1984 - Heliotronic Forschungs-und Entwicklungsgesellschaft fur Solarzellen- Grundstoffe mbH - Process for the purification of silicon by the action of an acid
* 4457903 - Filed Mar 1, 1983 - Heliotronic Forshungs und Entwicklungsgesellschaft fur Solarzellen Grundstoffe mbH - Semicontinuous process for the production of pure silicon
* 4572812 - Method and apparatus for casting conductive and semiconductive materials
There is a ton of Balance-of-System issues before anything real could happen, but these are starting places to talk it out.