Re: [Vo]:Problem with glare at Ivanpah CSP plant
Jed, Does it count as a kill if there is no evidence left? Ivanpah employees and OLE staff noticed that close to the periphery of the tower and within the reflected solar field area, streams of smoke arise when an object crosses the solar flux fields aimed at the tower. Ivanpah employees use the term 'streamers' to characterize this occurrence. When OLE staff visited the Ivanpah Solar plant, we observed many streamer events. It is claimed that these events represent the combustion of loose debris, or insects. Although some of the events are likely that, there were instances in which the amount of smoke produced by the ignition could only be explained by a larger flammable biomass such as a bird. Indeed, OLE staff observed birds entering the solar flux and igniting, consequently becoming a streamer. OLE staff observed an average of one streamer event every two minutes. It appeared that the streamer events occurred more frequently within the 'cloud' area adjacent to the tower. Therefore we hypothesize that the 'cloud' has a very high temperature that is igniting all material that traverses its field. On Thu, Apr 10, 2014 at 10:04 AM, Jed Rothwell jedrothw...@gmail.comwrote: See: http://www.renewableenergyworld.com/rea/news/article/2014/04/concentrating-solar-power-under-fire-glaring-planning-oversight-or-easily-remedied-issue QUOTES [Clifford Ho of Sandia National Laboratories’ Concentrating Solar Technologies Department says] “I believe some of the glare that’s being viewed is taking place when the heliostats are in a standby mode.” During peak daylight hours, it is common for a number of heliostat mirrors to be taken offline to prevent heliostats from directing more thermal energy to the turbine than it is capable of receiving. Ho said that during standby, these heliostats are focused on aim points next to the receiver, forming a ring of glare above the tower. According to Ho, the sunlight reflected from heliostats that are in standby mode could be having an exacerbating effect on the amount of reflection being emitted. In examining photos of the glare taken by passengers flying over the Ivanpah plant, Ho said it’s apparent to him the intense light is emanating from the heliostats not in use. “You can clearly see the difference between what’s just the diffuse reflection from the towers versus one or more heliostats that are in standby mode and reflecting light toward the observer.” Ho has performed helicopter surveys of heliostats in standby mode at Sandia National Laboratories’ National Solar Thermal Test Facility. “It’s bright,” he said, emphasizing that the Sandia CSP array is much smaller than that of Ivanpah. “When you’re close, it can be like looking into the sun.” . . . One possible solution, as suggested by Ho, is to reposition heliostats that are in standby mode so that they stand vertically — thus reflecting the glare toward the ground instead of upward. - Jed
Re: [Vo]:Problem with glare at Ivanpah CSP plant
ChemE Stewart cheme...@gmail.com wrote: Does it count as a kill if there is no evidence left? When OLE staff visited the Ivanpah Solar plant, we observed many streamer events. It is claimed that these events represent the combustion of loose debris, or insects. Although some of the events are likely that, there were instances in which the amount of smoke produced by the ignition could only be explained by a larger flammable biomass such as a bird. . . . That is distressing yet somehow hilarious, similar to Arthur Clarke's story about the referee who met that fate. - Jed
Re: [Vo]:Problem with glare at Ivanpah CSP plant
Humans are Cruel https://www.youtube.com/watch?v=zbkNDc_FoiU On Thu, Apr 17, 2014 at 9:47 AM, Jed Rothwell jedrothw...@gmail.com wrote: ChemE Stewart cheme...@gmail.com wrote: Does it count as a kill if there is no evidence left? When OLE staff visited the Ivanpah Solar plant, we observed many streamer events. It is claimed that these events represent the combustion of loose debris, or insects. Although some of the events are likely that, there were instances in which the amount of smoke produced by the ignition could only be explained by a larger flammable biomass such as a bird. . . . That is distressing yet somehow hilarious, similar to Arthur Clarke's story about the referee who met that fate. - Jed
Re: [Vo]:Problem with glare at Ivanpah CSP plant
I was a circuit designer, starting with tubes, then transistors and then programmable gate arrays. Didn't break into gates until long after I wanted to. As a teen, was dabbling in relay logic, telescope design, astronomy, geology, theology, fossils... Now am into peak oil. Greatly recommend The Archdruid's Report. Ol' Bab (old Babcock - I coined this in my 40s, now look at me) PS Am glad you got to see my post: I haven't seen it yet. Maybe only you has seen it. On 4/10/2014 4:16 PM, Bob Cook wrote: OlBab-- What kind of engineer were you? Older Bob? - Original Message - *From:* David L Babcock mailto:olb...@gmail.com *To:* vortex-l@eskimo.com mailto:vortex-l@eskimo.com *Sent:* Thursday, April 10, 2014 1:55 PM *Subject:* Re: [Vo]:Problem with glare at Ivanpah CSP plant It is a little more complex. There is a distance from the (presumed flat) mirror such that the angular extent of the mirror is about the same as that of the sun (1/2 deg). From there out the intercepted flux decreases, by the square of the distance. From the birds view, at that distance it sees the whole sun fill the mirror. Any farther out the image is bigger than the mirror -only part of the sun is supplying heat. If the mirrors are curved, then each mirror will have a hot focal point, but not super hot: again it is limited by the angular extent of the sun and the mirror. A ideal mirror will project an image of the sun on the boiler (or bird, if at focus), and the intensity is that of sunlight multiplied by the square of the ratio of the two angular extents. Maybe 10 or 20 to 1? WAG here. As Bob points out, the nimbus effect strongly suggests that the designers were aware of a possible problem and made sure mirrors in standby don't all point at a single point, or even parallel. Ol' Bab, who was an engineer.
[Vo]:Problem with glare at Ivanpah CSP plant
See: http://www.renewableenergyworld.com/rea/news/article/2014/04/concentrating-solar-power-under-fire-glaring-planning-oversight-or-easily-remedied-issue QUOTES [Clifford Ho of Sandia National Laboratories' Concentrating Solar Technologies Department says] I believe some of the glare that's being viewed is taking place when the heliostats are in a standby mode. During peak daylight hours, it is common for a number of heliostat mirrors to be taken offline to prevent heliostats from directing more thermal energy to the turbine than it is capable of receiving. Ho said that during standby, these heliostats are focused on aim points next to the receiver, forming a ring of glare above the tower. According to Ho, the sunlight reflected from heliostats that are in standby mode could be having an exacerbating effect on the amount of reflection being emitted. In examining photos of the glare taken by passengers flying over the Ivanpah plant, Ho said it's apparent to him the intense light is emanating from the heliostats not in use. You can clearly see the difference between what's just the diffuse reflection from the towers versus one or more heliostats that are in standby mode and reflecting light toward the observer. Ho has performed helicopter surveys of heliostats in standby mode at Sandia National Laboratories' National Solar Thermal Test Facility. It's bright, he said, emphasizing that the Sandia CSP array is much smaller than that of Ivanpah. When you're close, it can be like looking into the sun. . . . One possible solution, as suggested by Ho, is to reposition heliostats that are in standby mode so that they stand vertically -- thus reflecting the glare toward the ground instead of upward. - Jed
Re: [Vo]:Problem with glare at Ivanpah CSP plant
What the Flux? 392 MW generated from steam turbine generators/30% Rankine Efficiency/85% heat transfer efficiency @ solar boiler/90% mirror efficiency = 1700 megawatts airborne flux, THAT IS A GOOD BIRD ZAPPER On Thu, Apr 10, 2014 at 10:04 AM, Jed Rothwell jedrothw...@gmail.comwrote: See: http://www.renewableenergyworld.com/rea/news/article/2014/04/concentrating-solar-power-under-fire-glaring-planning-oversight-or-easily-remedied-issue QUOTES [Clifford Ho of Sandia National Laboratories' Concentrating Solar Technologies Department says] I believe some of the glare that's being viewed is taking place when the heliostats are in a standby mode. During peak daylight hours, it is common for a number of heliostat mirrors to be taken offline to prevent heliostats from directing more thermal energy to the turbine than it is capable of receiving. Ho said that during standby, these heliostats are focused on aim points next to the receiver, forming a ring of glare above the tower. According to Ho, the sunlight reflected from heliostats that are in standby mode could be having an exacerbating effect on the amount of reflection being emitted. In examining photos of the glare taken by passengers flying over the Ivanpah plant, Ho said it's apparent to him the intense light is emanating from the heliostats not in use. You can clearly see the difference between what's just the diffuse reflection from the towers versus one or more heliostats that are in standby mode and reflecting light toward the observer. Ho has performed helicopter surveys of heliostats in standby mode at Sandia National Laboratories' National Solar Thermal Test Facility. It's bright, he said, emphasizing that the Sandia CSP array is much smaller than that of Ivanpah. When you're close, it can be like looking into the sun. . . . One possible solution, as suggested by Ho, is to reposition heliostats that are in standby mode so that they stand vertically -- thus reflecting the glare toward the ground instead of upward. - Jed
Re: [Vo]:Problem with glare at Ivanpah CSP plant
ChemE Stewart cheme...@gmail.com wrote: Efficiency/85% heat transfer efficiency @ solar boiler/90% mirror efficiency = 1700 megawatts airborne flux, THAT IS A GOOD BIRD ZAPPER Close to the tower it would be. When a bird flies a few meters away from the surface of one mirror, it is no different than flying in full sunlight or in sunlight reflected from glass or water. I do not know at what distance from the tower the beams of light join together to be brighter and hotter than ordinary sunlight. I expect birds would not approach the tower because it is so bright. Millions of birds are killed by smoke from coal plants, and steam from coal, gas and nuke plants. - Jed
Re: [Vo]:Problem with glare at Ivanpah CSP plant
In high winds, mirrors go to flat position and all of the flux goes incident and airborne. Ivanpah is a high wind area. http://www.nabsa.org On Thursday, April 10, 2014, Jed Rothwell jedrothw...@gmail.com wrote: ChemE Stewart cheme...@gmail.comjavascript:_e(%7B%7D,'cvml','cheme...@gmail.com'); wrote: Efficiency/85% heat transfer efficiency @ solar boiler/90% mirror efficiency = 1700 megawatts airborne flux, THAT IS A GOOD BIRD ZAPPER Close to the tower it would be. When a bird flies a few meters away from the surface of one mirror, it is no different than flying in full sunlight or in sunlight reflected from glass or water. I do not know at what distance from the tower the beams of light join together to be brighter and hotter than ordinary sunlight. I expect birds would not approach the tower because it is so bright. Millions of birds are killed by smoke from coal plants, and steam from coal, gas and nuke plants. - Jed
Re: [Vo]:Problem with glare at Ivanpah CSP plant
Bob Cook frobertc...@hotmail.com wrote: The mirrors would not be focused at one spot when idle. Also it is a good idea to reduce global warming by directing the light back into space instead into the ground. Since it is near an airport I think it would be better to aim for the ground. I wonder . . . could you focus them on the parking lot? That would make a good murder mystery. A jealous lover is the programmer in charge of the array. Her boyfriend parks his car, walks toward the building . . . He does not notice the mirrors turning toward him. He vanishes in a puff of smoke. The mirrors swing back. No trace of the program code or activity log is found. Arthur Clarke wrote two short stories along those lines. - Jed
Re: [Vo]:Problem with glare at Ivanpah CSP plant
Terry Blanton hohlr...@gmail.com wrote: In 1958, the science fiction author Arthur C. Clarke published A Slight Case of Sunstroke . . . In the story, a large number of hostile spectators aim reflective program covers at the unfortunate umpire, who collapses and dies from the concentrated solar energy focused where he stood. He doesn't just collapse and die. It takes place in South America. The stadium has thousands army troops in the audience. Halfway through the game, a whistle blows, and the troops all aim their reflective programs at the ref, who vanishes in a puff of smoke. The other story is about an astronomer who murders his wife by aiming a searchlight at her car as she is driving home along the edge of cliff, late at night. - Jed
Re: [Vo]:Problem with glare at Ivanpah CSP plant
It is a little more complex. There is a distance from the (presumed flat) mirror such that the angular extent of the mirror is about the same as that of the sun (1/2 deg). From there out the intercepted flux decreases, by the square of the distance. From the birds view, at that distance it sees the whole sun fill the mirror. Any farther out the image is bigger than the mirror -only part of the sun is supplying heat. If the mirrors are curved, then each mirror will have a hot focal point, but not super hot: again it is limited by the angular extent of the sun and the mirror. A ideal mirror will project an image of the sun on the boiler (or bird, if at focus), and the intensity is that of sunlight multiplied by the square of the ratio of the two angular extents. Maybe 10 or 20 to 1? WAG here. As Bob points out, the nimbus effect strongly suggests that the designers were aware of a possible problem and made sure mirrors in standby don't all point at a single point, or even parallel. Ol' Bab, who was an engineer. On 4/10/2014 11:06 AM, Bob Cook wrote: The mirrors would not be focused at one spot when idle. Also it is a good idea to reduce global warming by directing the light back into space instead into the ground. - Original Message - *From:* Jed Rothwell mailto:jedrothw...@gmail.com *To:* vortex-l@eskimo.com mailto:vortex-l@eskimo.com *Sent:* Thursday, April 10, 2014 7:59 AM *Subject:* Re: [Vo]:Problem with glare at Ivanpah CSP plant ChemE Stewart cheme...@gmail.com mailto:cheme...@gmail.com wrote: Efficiency/85% heat transfer efficiency @ solar boiler/90% mirror efficiency = 1700 megawatts airborne flux, THAT IS A GOOD BIRD ZAPPER Close to the tower it would be. When a bird flies a few meters away from the surface of one mirror, it is no different than flying in full sunlight or in sunlight reflected from glass or water. I do not know at what distance from the tower the beams of light join together to be brighter and hotter than ordinary sunlight. I expect birds would not approach the tower because it is so bright. Millions of birds are killed by smoke from coal plants, and steam from coal, gas and nuke plants. - Jed
Re: [Vo]:Problem with glare at Ivanpah CSP plant
OlBab-- What kind of engineer were you? Older Bob? - Original Message - From: David L Babcock To: vortex-l@eskimo.com Sent: Thursday, April 10, 2014 1:55 PM Subject: Re: [Vo]:Problem with glare at Ivanpah CSP plant It is a little more complex. There is a distance from the (presumed flat) mirror such that the angular extent of the mirror is about the same as that of the sun (1/2 deg). From there out the intercepted flux decreases, by the square of the distance. From the birds view, at that distance it sees the whole sun fill the mirror. Any farther out the image is bigger than the mirror -only part of the sun is supplying heat. If the mirrors are curved, then each mirror will have a hot focal point, but not super hot: again it is limited by the angular extent of the sun and the mirror. A ideal mirror will project an image of the sun on the boiler (or bird, if at focus), and the intensity is that of sunlight multiplied by the square of the ratio of the two angular extents. Maybe 10 or 20 to 1? WAG here. As Bob points out, the nimbus effect strongly suggests that the designers were aware of a possible problem and made sure mirrors in standby don't all point at a single point, or even parallel. Ol' Bab, who was an engineer. On 4/10/2014 11:06 AM, Bob Cook wrote: The mirrors would not be focused at one spot when idle. Also it is a good idea to reduce global warming by directing the light back into space instead into the ground. - Original Message - From: Jed Rothwell To: vortex-l@eskimo.com Sent: Thursday, April 10, 2014 7:59 AM Subject: Re: [Vo]:Problem with glare at Ivanpah CSP plant ChemE Stewart cheme...@gmail.com wrote: Efficiency/85% heat transfer efficiency @ solar boiler/90% mirror efficiency = 1700 megawatts airborne flux, THAT IS A GOOD BIRD ZAPPER Close to the tower it would be. When a bird flies a few meters away from the surface of one mirror, it is no different than flying in full sunlight or in sunlight reflected from glass or water. I do not know at what distance from the tower the beams of light join together to be brighter and hotter than ordinary sunlight. I expect birds would not approach the tower because it is so bright. Millions of birds are killed by smoke from coal plants, and steam from coal, gas and nuke plants. - Jed
