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OwlFancier posted:Perhaps the complexity of their production does not outweigh the increase in efficiency except when transport costs are tens of thousands of dollars per pound? If you can make a detailed argument why necessarily that is and always will be the case, I'd be interested in hearing it. People also complain about the material cost/scarcity too. But I can say that the reason why the production cost is high is because they are a boutique product, and the boutique manufacturers can't afford the up-front costs needed to be more efficient and/or haven't been seriously motivated to improve their production efficiency. Regarding the material cost, you need way less III-V semi-conductor to be able to absorb all of the sunlight when compared to silicon, and the many orders of magnitude difference in scarcity of some of the III-V semi-conductors and silicon isn't super relevant because the availability of silicon isn't really a bottleneck of solar silicon production. Put another way, silicon could probably be 1000x more scarce, and it probably wouldn't affect the solar silicon price that much. Put in yet another way, you don't really need that much raw materials to make solar cells--they can be very thin.
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Dec 10, 2015 18:15
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silence_kit posted:I understand why space people will pay almost anything for a higher efficiency cell. What I don't understand, and no one has ever convinced me of this, is why the III-V cells necessarily must be high cost. I think that most of the high cost is just a consequence of the III-V semi-conductor electronics industry being a boutique electronics industry servicing customers who are willing to pay a lot of money for their products. Isn't manufacturing a multijunction cell always going to be more expensive than a single-junction cell, if nothing else due to the additional process steps required in fab? If you want multiple bandgaps, you need multiple dopants, multiple layers, tunnel junctions between the layers, which means a more complicated manufacture. I take no position on that having to be "high cost," but it seems likely that it's going to be high*er* cost than single-junction cells.
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Dec 10, 2015 18:23
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I mean perhaps it's a case of where there isn't a demand for exceptionally high grade solar panelling? Sort of in the same sense that you can make all knives out of very good quality spring steel or something but people will often prefer to pay for crappy stuff made out of compressed tin cans or whatever because they work well enough. I don't know, where's most of the market for solar panels at the moment? Who's buying them? Because if it's heavily weighted towards rooftop panels then the optimal panel is sort of determined by the roof-to-generation ratio. I believe there's laws prohibiting people from actually generating much power in their homes, so rooftop panels are limited to offsetting power usage during the day, which means you don't want better panels than you need to offset power usage. Certainly if storage were more available so people could make more use of rooftop generation then perhaps better panels may be more desirable, or if there were significant demand for commercial solar power stations using high end PV panels, but as it stands I can only suggest that perhaps current mid-range panels are perfectly functional for most applications so you're not likely to see a development of better ones until there is a need for them? I don't think anyone would argue that there's some fundamental law of physics which means that high output solar panels have to be expensive but I can certainly see where there would be a bit of a chicken/egg thing going on where mediocre panels are good enough so there is no demand to drive the mass production of better ones, so they stay expensive and people don't buy them.
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Dec 10, 2015 18:26
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In other news, Wendelstein 7-x achieved first plasma today, with Helium for the initial year of testing before moving on to Hydrogen. And it only cost 370 million euros.
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Dec 10, 2015 18:47
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I CANNOT EJACULATE WITHOUT SEEING NATIVE AMERICANS BRUTALISED!
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Phanatic posted:Isn't manufacturing a multijunction cell always going to be more expensive than a single-junction cell, if nothing else due to the additional process steps required in fab? If you want multiple bandgaps, you need multiple dopants, multiple layers, tunnel junctions between the layers, which means a more complicated manufacture. It all depends on how much those extra steps cost relative to all of the costs involved in solar electricity. If the cell manufacturing costs are dwarfed by all of the other stuff that goes into the price of electricity, it makes sense to pay more for more efficient cells, since higher efficiency cells reduce ALL of the costs that scale with area, and not just the cell manufacturing cost. A lot of people say that epitaxy (the technique used to make the multiple junctions in the tandem solar cell) is fundamentally expensive, but I see no reason why that has to be the case. Two confounding factors are that a lot of researchers who say this derive this opinion from buying custom epi-wafers and having to pay for an engineer to work out the growth recipe and verify it, significantly raising the wafer cost. Another one is that the industry that does a lot of hetero-epitaxy (opto-electronics, basically semiconductor lasers, photo detectors, and light-emitting diodes) likes to use very very thin layers and uses low growth rates. They are also much smaller area devices and so are less sensitive to production cost. Solar cells don't really need the quantum wells and so they can be grown at higher growth rates. silence_kit fucked around with this message at 00:08 on Dec 31, 2015 |
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Dec 10, 2015 18:57
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High quality UHV epitaxy to create single crystal films is sort of fundamentally expensive since the vacuum processes required do not lend themselves to high throughput. Low throughput + expensive equipment is not a recipe for low costs. But the mere process of depositing precisely controlled very thin films is not inherently expensive. The disks used in HDDs, for example, have dozens of coatings with thicknesses between 0.1 and 100 nanometers, and the overall production cost is in the neighborhood of ~$10 per square meter of substrate coated. If you want high quality single crystal films with very few defects, though, I don't think you could achieve costs like that.
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Dec 10, 2015 21:07
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OwlFancier posted:I believe there's laws prohibiting people from actually generating much power in their homes, so rooftop panels are limited to offsetting power usage during the day, which means you don't want better panels than you need to offset power usage. Where did you get that idea from? To be honest there are cases where if you're putting a very large amount of power on the grid you become required to submit to increased regulatory scrutiny for safety reasons. But you can't make that much power on a typical middle class residential lot, even if you coated your yard and everything else with solar too - you'd need to have some manner of country estate with vast amounts of land given over to the solar panels, and probably to have spent many thousands of dollars to build it out.
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Dec 10, 2015 21:17
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Morbus posted:High quality UHV epitaxy to create single crystal films is sort of fundamentally expensive since the vacuum processes required do not lend themselves to high throughput. Low throughput + expensive equipment is not a recipe for low costs. But the mere process of depositing precisely controlled very thin films is not inherently expensive. The disks used in HDDs, for example, have dozens of coatings with thicknesses between 0.1 and 100 nanometers, and the overall production cost is in the neighborhood of ~$10 per square meter of substrate coated. If you want high quality single crystal films with very few defects, though, I don't think you could achieve costs like that. You don't need ultra high vacuum to achieve epitaxy. Chemical vapor deposition (CVD) techniques are the most economical techniques and are extremely popular and do not require high vacuum. I wouldn't fret about the cost of the CVD reactor if it has high enough throughput. That is how high volume manufacturers think.
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Dec 10, 2015 21:38
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fishmech posted:Where did you get that idea from? To be honest there are cases where if you're putting a very large amount of power on the grid you become required to submit to increased regulatory scrutiny for safety reasons. But you can't make that much power on a typical middle class residential lot, even if you coated your yard and everything else with solar too - you'd need to have some manner of country estate with vast amounts of land given over to the solar panels, and probably to have spent many thousands of dollars to build it out. Wasn't there some thing in the news a while back about some daft arses that covered their entire house in panels and ended up being classified as a power plant or something?
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Dec 10, 2015 21:41
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OwlFancier posted:Wasn't there some thing in the news a while back about some daft arses that covered their entire house in panels and ended up being classified as a power plant or something? If anything that was likely just because the utility wanted to pay them less for power produced or otherwise hadn't figured out a better way to handle someone generating more than the limit they could handle with installed hardware.
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Dec 10, 2015 22:02
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OwlFancier posted:Wasn't there some thing in the news a while back about some daft arses that covered their entire house in panels and ended up being classified as a power plant or something? That would have had to be quite a large house! Also if they were even covering the walls and such, then most of their capacity would never get sufficient sunlight to be useful. We stick to putting the panels on roofs, and facing towards where the sun is most often for a reason!
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Dec 10, 2015 22:05
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I have a hard time believing that a house got classified as a power plant when I'm sure there are businesses with greater generating capacity thanks to on-site backup generators. If it's true (which would be hosed up), I think either there's a regulation or policy (whether legal or corporate) that's been grossly unevenly applied, or someone was a real tinpot rear end in a top hat. That said, I do recall hearing about there being regulations governing home power generation when there's a grid outage - but my understanding is that that's intended to protect the lives of line workers who need to be able to trust that when they talk to the central office and are told the power is off for the line they're working on, it's not being quietly energized by someone who hosed up big time when they wired up their solar array.
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Dec 10, 2015 22:11
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I can't remember but I think it was somewhere in california and someone commented that it would be an absurd amount of panelling for home use. I can't remember what the regulation was but I think it was something about having potentially too much output into the grid or something? Not an actual federal law or anything, maybe some city ordnance or state law. Ah, found it, I think: http://www.nbclosangeles.com/news/local/Solar-Panel-Too-Much-Power-Energy-Retailer-323024971.html The idea seems to be that if you generate more power than you use, you classify as a commercial business and the energy company won't rebate you for it (you actually have to sell it yourself) and also there's a state limitation on power generation for a residence. Frustratingly the article doesn't give sources. OwlFancier fucked around with this message at 22:35 on Dec 10, 2015 |
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Dec 10, 2015 22:26
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QuarkJets posted:First, you're focusing on the efficiency of converting photons into electrons, and it's true that research on cutting-edge maximum efficiency panels does not meaningfully impact the end-cost of solar PV. I think that this is short-sighted; there are a million other ways in which research has benefitted the end-cost of residential PV. For instance, we have much more efficient microinverters and much more efficient silicon harvesting techniques than we did 20 years ago. These kinds of technologies (and others) have had a significant impact on the cost of residential PV. Depending on how broad your definition of "research" is, it is at some point difficult to discriminate between experience curve effects and research. To clarify the scope of my argument, I am saying that externally funded e.g. university research has not been a major contributor to the reduction in PV costs. To further focus the scope of my argument, I'm going to, for now anyway, focus on polycrystalline Si PV cells, since those are overwhelmingly the type being employed today due to very favorable cost/efficiency tradeoff. My points are as follows: 1. Conventional poly Si (and mono Si) photovoltaics are silicon pn junctions. The fundamental technology used to create these has not changed in decades. Today's best poly-Si cells have efficiencies of around 15-16%, and the best monocrystalline cells have efficiencies of around 20-25%. You can easily find examples of PVs being made in the 70's and certainly 80's with performance very close to this; you argue that, while technically true, these were (presumably expensive) research or space cells, and not mass market photovoltaics. This isn't the case. To the extent that efficiency gains have been made in silicon PV cells over the last few decades, most of it has been fairly mundane stuff like improvement in antireflective coatings, and even then the cumulative gains from all of this development has been in the neighborhood of a few percentage points vs. what was being made in the 70's. Rather than try to substantiate this with a 40 year history of PV development, I will just point out that a 30 year old poly-Si module (tested in 2015...), produced about 30 watts in direct sunlight, for a module that has 0.26m^2 effective area if you look up the datasheet: http://www.greenbuildingadvisor.com/blogs/dept/musings/testing-thirty-year-old-photovoltaic-module That's a ~12% efficiency for a mass market 1970's PV module, compared to maybe 16% today. For a 30 year old module which we would expect to have some degradation. 2. Since the mid 1970s (before which mass market solar wasn't really a thing), the price per watt of conventional PV has dropped by more than a factor of 100. To the extent that improvements have been made in the intrinsic peformance of PV modules, it is on the order of ~35%, e.g. 16 vs 12%, or 25 vs 18% (and this is being very generous), Therefore, of the cumulative 100000% drop in price, very little of this can be attributed to any improvements in PV performance, whether the result of academic research, corporate research, experience curve effects, or whatever. So, I stand by my statement that PV modules are basically 1970's technology. The intrinsic performance and operating characteristics of conventional photovoltaics have not changed appreciably since the 1970's, and they certainly have not changed in an amount even remotely commensurate with the reduction in $/Watt that has occurred in the same time span. Your analogy comparing 19th century car engines to day is not a good one. A modern car engine is laughably superior to one from the 1970's in almost every way, let alone a toy from the 19th century, and has substantial technological differences (computer control, combustion sensors, direct fuel injection, catalytic converters, variable timing...) Now, you also point out that I'm focusing on research efforts to developing new (more efficient or otherwise disruptive) PV technology, and attributing the cost reduction of old technology purely to experience curve, economy and scale, and other non-academic sources of improvement. You argue, that research spending has been an important factor in the process improvements and economic factors that have driven down costs so much. I disagree with this, although its a harder argument to make and a longer one so I will maybe leave it for a later post. I will quicky point out, though that -It is pretty clear that the dramatic reduction in costs is not due to revolutions in process technology, but mostly a direct effect of scaling up factory sizes. -There have not been any major process technology revolutions in e.g wafer/ingot manufacturing or metalization, which are the key material process costs for solar. Rather, price drops in, for example ingot prices are pretty demonstrably related to economies of scale and the move towards larger wafer sizes. -Examination of the literature indicates most PV research has not focused on process technology cost reductions. It has focused, as it should, on new PV technology or fundamental research. -Academic research, in general, is poorly suited to drive down process costs in mundane (e.g. non-disruptive) ways. The resources a university can allocate to the task are utterly dwarfed by what corporations can spend, and the incentives are not really there. Nobody doing PV research ever got tenure for writing a paper about how to get 10% better sputter target utilization in a metalization process. Note: I am not saying research into photovoltaics isn't important; it is! Very! I sincerely believe that there are disruptive technologies on the (far-ish) horizon that can significantly improve the efficiency of PV modules while also driving down costs very substantially. There are no fundamental reasons why, for example, a low cost reasonably efficient thin film solar technology cant be developed. And research institutions are well positioned to developing these things, at least initially, since they are not burdened by the need to make a profit this quarter. For the last 30 years, no disruptive solar cell technology has emerged to displace conventional Si photovoltaics, but that doesn't mean it never will. That is a pretty poo poo business proposition, but if we only investigated things that made good business plans we would be living in caves. Morbus fucked around with this message at 22:58 on Dec 10, 2015 |
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Dec 10, 2015 22:53
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Morbus posted:Note: I am not saying research into photovoltaics isn't important; it is! Very! I sincerely believe that there are disruptive technologies on the (far-ish) horizon that can significantly improve the efficiency of PV modules while also driving down costs very substantially. There are no fundamental reasons why, for example, a low cost reasonably efficient thin film solar technology cant be developed. And research institutions are well positioned to developing these things, at least initially, since they are not burdened by the need to make a profit this quarter. For the last 30 years, no disruptive solar cell technology has emerged to displace conventional Si photovoltaics, but that doesn't mean it never will. It doesn't make sense to me to research technologies that don't have a prayer of beating silicon in efficiency. Why go through all the trouble of building up production of an alternate technology so you can produce at lower cost, to achieve something that is functionally the same or worse than a silicon solar cell? That doesn't make sense to me, especially since the cell manufacturing cost isn't the biggest cost of solar electricity. If there is going to be a new solar cell technology, it has to be more efficient than silicon. silence_kit fucked around with this message at 23:48 on Dec 10, 2015 |
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Dec 10, 2015 23:45
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Farmer Crack-rear end posted:That said, I do recall hearing about there being regulations governing home power generation when there's a grid outage - but my understanding is that that's intended to protect the lives of line workers who need to be able to trust that when they talk to the central office and are told the power is off for the line they're working on, it's not being quietly energized by someone who hosed up big time when they wired up their solar array. Most home solar systems in the US will trip off if they lose grid connection and refuse to energize without one. Its like nuclear in that way. 
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Dec 11, 2015 01:14
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Morbus posted:The prevailing trends in cost per kWh are purely due to experience curve and economy of scale type effects, which are generic and expected for any industry when production volume increases greatly. Morbus posted:Depending on how broad your definition of "research" is, it is at some point difficult to discriminate between experience curve effects and research. To clarify the scope of my argument, I am saying that externally funded e.g. university research has not been a major contributor to the reduction in PV costs. This, and some other parts of your post, is you moving the goal posts from "research has had no effect" to "research has had some effect". You also continue talking about PV performance, so let me try and make my position extremely clear: I do not believe that research into PV performance has had a significant impact on the cost of residential PV. We both agree that PV research is important and has had benefits for residential solar power customers, and that's really the only point of contention that I wanted to address. A good discussion for all. You've suggested that you may want to write another post to address the idea that research efforts have been super important toward reducing solar PV costs, but I'd like to reiterate that no one in this thread is making that argument. My position is that research has had an effect on the price of residential PV, not that it's a driving force behind cost reduction: QuarkJets posted:I don't think that anyone is arguing that those gains, or any of the gains in the realm of solar power cost reduction, are largely research-driven. The argument is that none of those gains were research-driven, which is plainly false QuarkJets posted:I believe that economies of scale and experience are making a big impact, but it's laughable to suggest that none of the research conducted in the last 40 years has had any cost impact.
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Dec 11, 2015 06:07
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silence_kit posted:It doesn't make sense to me to research technologies that don't have a prayer of beating silicon in efficiency. Why go through all the trouble of building up production of an alternate technology so you can produce at lower cost, to achieve something that is functionally the same or worse than a silicon solar cell? That doesn't make sense to me, especially since the cell manufacturing cost isn't the biggest cost of solar electricity. If there is going to be a new solar cell technology, it has to be more efficient than silicon. Price/kW might be a really important quality for residential PV, but other designs might have requirements that silicon panels don't satisfy.
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Dec 11, 2015 06:13
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OwlFancier posted:I don't know, where's most of the market for solar panels at the moment? Who's buying them? Because if it's heavily weighted towards rooftop panels then the optimal panel is sort of determined by the roof-to-generation ratio. I believe there's laws prohibiting people from actually generating much power in their homes, so rooftop panels are limited to offsetting power usage during the day, which means you don't want better panels than you need to offset power usage.  The roof space for a standard residence far exceeds the necessary amount required to offset their own usage in the US. Different states have different methods of how they set things up though. For California, your electrical bill becomes annual and you are compensated for generation at the same rate you would be charged if you were using that electricity. Right now decentralized generation is highly beneficial overall as it is offsetting decentralized usage of daytime airconditioning usage, overall there is less transmission distance needed and so less transmission losses. In 2016 California's future rooftop solar generation compensation agreements will change because the amount generated by solar is going to soon be more than the increased daytime usage and would require a quick grid generation ramp-up as soon as the sun goes down. My preferred solution to this would be residential battery backup incentives that would smooth the ramp-up time and allow solar to continue to grow. OwlFancier posted:I can't remember but I think it was somewhere in california and someone commented that it would be an absurd amount of panelling for home use. The couple here did a power-purchase agreement, Solar City retained ownership of the panels after installation and were going to be taking over the electric account of the couple. The couple would then buy their power from Solar City at a significantly reduced rate. Solar City would then be eligible to make their money back by receiving the incentives as well as MACRS depreciation then selling power at a set rate per kWh to the homeowners for 10 to 25 years depending on the agreement. Solar City aimed to offset 100% of what the couple had historically generated then likely estimated that with the couple having just retired they would be home more, use more AC and so they would have increased usage so set a system for them to generate 128% of what they had historically used, the couple said they had no plans to increase usage. The electric company said that if Solar City was a corporation with an array over 110% of site usage with no plans to increase usage, then they were going to have to follow the regulations for energy retailers not residential/commercial generation rules. The couple were clearly high energy users, they could have legally connected a 30 panel system in the best region in the US for solar access. Had they promised to increase their electrical usage, they would have been allowed to turn the system on, or even if they had just given Solar City permission to remove 6 panels and refile the interconnection form. Residential grid-connected solar panels are for offsetting your own usage, not for selling to the grid, so if you are trying to set up a grid-connected system which generates more than 110% of what you use, you have to promise in writing that you plan to increase your usage. If you do not actually increase your usage, it is OK, you will just get credited at a lower rate for your excess generation. If you set up a grid-tied system where you generate more than 110% of your usage and also say in writing you do not intend to increase your usage, then the power company will assume you are intending to sell that excess generation and will require you to register as a retailer for that excess. fermun fucked around with this message at 10:00 on Dec 11, 2015 |
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Dec 11, 2015 09:58
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When in doubt, go for the comedy option.quote:During the Woodland Town Council meeting, one local man, Bobby Mann, said solar farms would suck up all the energy from the sun and businesses would not go to Woodland, the Roanoke-Chowan News Herald reported. I have no words.
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Dec 13, 2015 23:09
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See now that just doesn't make sense, solar panels eat sunlight so obviously they protect you from UV radiation.
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Dec 13, 2015 23:11
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I will not allow low carbon infiltration, low carbon subversion, and the international low carbon conspiracy to sap and impurify our precious solar irradiation.
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Dec 13, 2015 23:15
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OwlFancier posted:See now that just doesn't make sense, solar panels eat sunlight so obviously they protect you from UV radiation. Solar panels soak up sunlight and amplifies UV. Ever wonder why areas with solar panels are hotter than areas without? The panels are frying everything around them. Every year around spring solar farms ramp up production of electricity and emit toxic radiation and the temps go up. Every year. The drought in California is more and larger solar farms baking the whole state. Germany built organic solar farms so they're ok.
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Dec 13, 2015 23:30
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I don't get why residential solar is still a custom-sized array of hand-installed individual panels. There should just be a standard ~4kw rig that can be hoisted up, bolted on, and tied in in an hour. Want to out-do the jones or have an electric car? Fine slap on two. It needs to be less like getting a bathroom renovated and more like buying a consumer product from ikea or apple. v I bet the mobile/manufactured 'doublewide' market and the urban 25x100ft lot market are plenty to get going. as long as it was somewhat adjustable that'd still probably cover half or more of the stick-frame/"custom" market. StabbinHobo fucked around with this message at 05:59 on Dec 14, 2015 |
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Dec 14, 2015 05:04
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Because every roof is the same geometry and can take exactly the same load at exactly the same points?
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Dec 14, 2015 05:11
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StabbinHobo posted:I don't get why residential solar is still a custom-sized array of hand-installed individual panels. There should just be a standard ~4kw rig that can be hoisted up, bolted on, and tied in in an hour. Want to out-do the jones or have an electric car? Fine slap on two. The kind of thing that you're describing already exists, I know of at least one UK company and two US companies that use standardized roof mounting systems that are versatile enough to handle most roofs with a variety of panel configurations. But even if you simplify the mounting job, it still takes a lot of skill and effort to install it correctly; that would be true even if every roof in the world was identical.
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Dec 14, 2015 11:40
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...and some people still get hosed over because their roof is slightly weird and Solar City won't touch it. No I'm not bitter. 
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Dec 16, 2015 20:46
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StabbinHobo posted:I don't get why residential solar is still a custom-sized array of hand-installed individual panels. There should just be a standard ~4kw rig that can be hoisted up, bolted on, and tied in in an hour. Want to out-do the jones or have an electric car? Fine slap on two. It is basically this but 1kw standard size so that they can be more flexible. Generally it takes a lot longer for the system to get approved once installed than for the system to be physically installed. But I also prefer a grid where this poo poo is inspected before being tied in.
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Dec 16, 2015 21:00
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The federal budget deal which is expected to be voted on tomorrow includes an extension of and rampdown of the solar ITC. If the bill passes, residential solar will still have a 30% tax credit through the end of 2019, a stepdown to 26% for 2020, and 22% for 2021. It is set to expire after that, but that does provide 5 more years of stability for residential solar.
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Dec 17, 2015 03:41
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Anyone here familiar with piezoelectric generators, because theres gonna be a test program of using them on roads? While this seems like a more suitable way to make a "green road" I'm just apprehensive that itll be able to withstand the rigors of road traffic, and almost certainly wont be able to handle trucks. Also how much would they generate in ideal conditions?Energy Harvesting Journal posted:Researchers at The University of Texas at San Antonio (UTSA) and the Texas A&M Transportation Institute (TTI) have been awarded a $1.32 million contract from the Texas Department of Transportation (TxDOT) as part of the jointly funded Federal Highway Administration's state research program. Its premise is to design and develop a system to harvest energy created by the movement of vehicles along the state's roadways and convert it into low-cost renewable electric power. The system also would allow TxDOT to continuously monitor the health of roadways to improve traveler safety.
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Dec 17, 2015 04:30
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fermun posted:The federal budget deal which is expected to be voted on tomorrow includes an extension of and rampdown of the solar ITC. If the bill passes, residential solar will still have a 30% tax credit through the end of 2019, a stepdown to 26% for 2020, and 22% for 2021. It is set to expire after that, but that does provide 5 more years of stability for residential solar. Under the current program, do you receive ongoing tax rebates or is it a year of install thing?
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Dec 17, 2015 04:43
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Communist Zombie posted:Anyone here familiar with piezoelectric generators, because theres gonna be a test program of using them on roads? While this seems like a more suitable way to make a "green road" I'm just apprehensive that itll be able to withstand the rigors of road traffic, and almost certainly wont be able to handle trucks. Also how much would they generate in ideal conditions? Just based on road wear patterns and levels (and the higher the expected energy return, the worse it'll be!), it's probably a boondoggle - but I certainly don't mind TTI getting some boondoggle money.
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Dec 17, 2015 04:52
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fishmech posted:Under the current program, do you receive ongoing tax rebates or is it a year of install thing? Year of install thing, however any unclaimed credit can be carried forward and back if your tax liability is too small, the rule is 1 year carryback and 20 years carryforward. It was not fully clear what was going to be possible with the carryforward if the 30% ITC had just ended, the carryforward is allowed for up to 20 years but also wording implies it being used while the 30% ITC is still around. The IRS hadn't announced a clarification on that. If your total tax liability were $1,500 per year and you had installed a $15,000 solar array, you could spread your $4,500 ITC over 3 years to claim the full $4,500.
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Dec 17, 2015 06:35
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GreyjoyBastard posted:Just based on road wear patterns and levels (and the higher the expected energy return, the worse it'll be!), it's probably a boondoggle - but I certainly don't mind TTI getting some boondoggle money. Not to mention from a physics standpoint. The cars and trucks are expending energy to move themselves down the road. If you're extracting energy from that process, you're fundamentally extracting it from the engines of the cars and trucks, so they have to burn a tiny bit more gas. So what's the benefit? How is this "clean"?
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Dec 17, 2015 16:39
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Phanatic posted:Not to mention from a physics standpoint. The cars and trucks are expending energy to move themselves down the road. If you're extracting energy from that process, you're fundamentally extracting it from the engines of the cars and trucks, so they have to burn a tiny bit more gas. So what's the benefit? How is this "clean"? Yeah, a lot of people don't understand this. Free energy ain't free.
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Dec 17, 2015 16:47
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Phanatic posted:Not to mention from a physics standpoint. The cars and trucks are expending energy to move themselves down the road. If you're extracting energy from that process, you're fundamentally extracting it from the engines of the cars and trucks, so they have to burn a tiny bit more gas. So what's the benefit? How is this "clean"? What I'm reading on it (here, for example) is that the compression/rebound in the asphalt is almost entirely lost as friction within the roadway and not restored to the car. Thus the piezo crystals are able to extract some of that energy that would otherwise be lost. The question seems to be whether or not the amount of energy actually extracted is worth the cost and complexity of the system overall.
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Dec 17, 2015 17:02
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I doubt the energy extracted is worthwhile or the true point of the system. From the sounds of it they're using "Green energy production" as a way to get funding. The real purpose and use would be to put the devices across lanes to get better traffic data.
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Dec 17, 2015 17:18
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This sounds like it's on the same level of the solar road. IIRC this might be okay for foot traffic maybe? Another idea I heard over the years is wind stuff near the road. The worst ideas are the wind stuff on cars and car/road magnet combos.
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Dec 17, 2015 20:35
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Ok here's my idea. We use solar roads to turn roads into moving sidewalks, the movement of the sidewalk is hooked up to generators that pump water up a dam to be stored and used to make hydrogen to power the cars. Just make it green all the way down, it will work.
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Dec 17, 2015 20:51
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PhazonLink posted:This sounds like it's on the same level of the solar road. IIRC this might be okay for foot traffic maybe? Another idea I heard over the years is wind stuff near the road. nah Solar Roadways is an insane, unworkable idea for a very long list of reasons. This is much simpler and might have some real world applications. Collecting sensor data in remote locations without having to run cables out there could be useful. Powering lamps and signs seems far fetched but we really have no numbers to work with so.... In 2008 a plucky Israeli company was doing the same thing and was expecting "400 kilowatts from a 1-kilometre stretch of dual carriageway". We may safely assume that's a bullshit number from a company trying to sell their tech - it's probably closer to 2-300 kilowatts, if that. It then depends on what it costs to deploy vs. running a cable + regular electricity. Another thing to note is that it would be an intermittent source of electricity following traffic patterns so it would have limited applications.
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Dec 17, 2015 21:11
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