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MIT Solar Towers Beat Solar Panels By Up To 20x

timothy posted more than 2 years ago | from the if-they-had-pants-they'd-have-been-beaten-off dept.

Technology 159

An anonymous reader writes "A team of MIT researchers has come up with a very different approach to solar collectors: building cubes and towers that extend solar cells upward in three-dimensional configurations. The results from the structures they've tested show power output ranging from double to more than 20 times that of fixed flat panels with the same base area (abstract, full pre-print). The biggest boosts in power were seen in the situations where improvements are most needed: in locations far from the equator, in winter months and on cloudier days."

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But... (-1)

Anonymous Coward | more than 2 years ago | (#39485739)

But can it beat my meat?

Re:But... (0)

stooo (2202012) | more than 2 years ago | (#39488169)

The problem of this approach is that it does not scale.
In real size photoelectric systems, the cells are in series. And this arrangement cannot cope with different angles, and partial panel shadows. The whole output of the string decreases to the weakest in the chain. Fail.

Picture... (5, Informative)

Anonymous Coward | more than 2 years ago | (#39485805)

Picture available here [extremetech.com] . It's a solar pancake!

Re:Picture... (3, Informative)

Firethorn (177587) | more than 2 years ago | (#39486823)

That's an interesting article, but I found the link about using an ion cannon [extremetech.com] to make cells 1/10th as thick at 1/2 the cost of cheap chinese cells to be potentially more revolutionary.

At this point we're not especially limited on space for solar installs. Our problem is that our collection systems aren't cheap enough.

Re:Picture... (4, Informative)

uigrad_2000 (398500) | more than 2 years ago | (#39487199)

The Ion cannon article was featured on Slashdot two weeks ago. [slashdot.org]

I think a better way to state it, would be to say that efficiency per square foot of ground used is not important, unless the cost of the cells come down.

Now that there is word of a new manufacturing process to reduce cost, two weeks later, we find an article about how to arrange low-cost cells.

Re:Picture... (3, Informative)

pla (258480) | more than 2 years ago | (#39487897)

At this point we're not especially limited on space for solar installs. Our problem is that our collection systems aren't cheap enough.

This. These 3d shapes give a better yield for a given footprint, but actually cost more.

Hey, If you can make individual flat panels cheaply enough, I'll pave half an acre with them for all I care about the "footprint". That said, I really don't understand why no major company has come up with mass produced smaller panels in a roofing-shingle form factor, but, entirely different topic.

Now, the part of this that does appeal to me involves the improved yield at high latitudes - But does that mean improved only against the footprint, or against the surface area? If the former, hey, cool, I live just far enough North that solar won't realistically pay back the investment given the present dominant efficiencies and prices; If the latter, then to repeat myself, just make 'em cheaper, I'll provide the space.

Solar shingles are available (2)

Medievalist (16032) | more than 2 years ago | (#39488439)

I really don't understand why no major company has come up with mass produced smaller panels in a roofing-shingle form factor, but, entirely different topic.

Solar shingles have been around for quite some time.

http://www.google.com/search?&q=solar+shingles [google.com]

If our conversation is going to follow the pattern of a typical slashdot discussion thread, you will now need to retroactively define the terms "major", "mass produced", and "smaller" in such a way that you can insist that I am not only wrong, but also a smelly hippy that likes Hitler.

Re:Picture... (1)

rrohbeck (944847) | more than 2 years ago | (#39488859)

Yield at high latitudes is not a big deal even for conventional solar arrays. Solar PV is huge in Germany (basically due to federally mandated feed-in tariffs for over a decade.)
Now consider that Berlin is at the latitude of South Hudson Bay.

Re:Picture... (4, Informative)

fast turtle (1118037) | more than 2 years ago | (#39488001)

Did you RTFA? I happened to do so having caught it a couple of days ago. The interesting element to this design is the early/late (dawn/dusk) power generation as the current method doesn't get enough solar incidence to generate anything until 3 hours after sunrise/3 hours before sunset. That's 6 hours of production that's being missed, which is why this design reaches 15-20x the generated power of conventional flat panels.

Re:Picture... (3, Informative)

icebike (68054) | more than 2 years ago | (#39488189)

Yeah, I read dud RTFA. It said:

While the cost of a given amount of energy generated by such 3-D modules exceeds that of ordinary flat panels, the expense is partially balanced by a much higher energy output for a given footprint, as well as much more uniform power output over the course of a day, over the seasons of the year, and in the face of blockage from clouds or shadows.

This suggests to me that there is no ROI on this method, or at least none that could not be more cheaply matched by simply tilting existing solar arrays [pureenergysolar.com] .

I don't discount the possibility that we are seeing another poorly written TFA, and that there is an eventual ROI. But the implication is that the generation of power early and power late in the day may never actually pay for the structures and maintenance needed to collect it, leaving you with zero net gain over a tilted array in northern latitudes.

Re:Picture... (0)

Anonymous Coward | more than 2 years ago | (#39489049)

There are some places where physically smaller panels may be useful even at a premium:
* satellite solar panels (particularly with the recent move towards electric propulsion)
* portable rechargers for camping
* battery chargers for yachts
* and solar-powered electric cars (http://www.worldsolarchallenge.org/)

Re:Picture... (1)

iamhassi (659463) | more than 2 years ago | (#39487547)

Picture available here [extremetech.com] . It's a solar pancake!

so if a solar pancake works, with the down facing solar panels and everything, what about stacking several cubes at their corners, like several of these [wikipedia.org] on top of each other? That way you don't have sections that are not facing sunlight like you do with the MIT solar pancake design since there's no solar panels on the side of the structure, [extremetech.com] with a cube balanced on a tip you'd have a sun facing panel at all times. Set-up would be a breeze too since you don't have to face it towards the sun like the MIT design.

Duh (1, Insightful)

The_mad_linguist (1019680) | more than 2 years ago | (#39485831)

Use 50 times as many solar cells, and OF COURSE you'll get more power out.

Re:Duh (0)

Anonymous Coward | more than 2 years ago | (#39485895)

Yeah and I don't see exactly how this is suppose to scale. If they're tall that means they will block light to the other cells in their shadow.

I mean it's not like they made the cell more efficient. The surface area is the same, just stacked vertically.

Re:Duh (1)

alphatel (1450715) | more than 2 years ago | (#39485983)

Yeah and I don't see exactly how this is suppose to scale. If they're tall that means they will block light to the other cells in their shadow.

I mean it's not like they made the cell more efficient. The surface area is the same, just stacked vertically.

This just in: increased surface area increases efficiency!

Re:Duh (1)

ILongForDarkness (1134931) | more than 2 years ago | (#39486265)

Haha. It is the three dimensional aspect i think. A ~2d panel only has a crossectional area proportional to the sin of the incident angle (and the panels are less efficient for oblique light too). Extending into 3D means the panels have approx the same crossectional area regardless of the suns angle in the sky. That said: way too much hardware involved. I have solar on my roof and on a clear day in the winter I get about 40% of the power as a clear day in the summer. But that only needs one panel. Getting 20X the panels to get that extra 60% of the power doesn't make sense to me. Just put the suckers on the ground with a tilt-able stand.

Re:Duh (1)

icebike (68054) | more than 2 years ago | (#39488331)

Getting 20X the panels to get that extra 60% of the power doesn't make sense to me. Just put the suckers on the ground with a tilt-able stand.

Exactly.
Or leave them on the roof with a tilt stand [pureenergysolar.com] .

Left unsaid in TFA is if these towers rotate to face the sun. Without that, you gain little except their ability to stack panels vertically, housing more panels per square foot. (At more cost). If space were a problem this might make sense, but it doesn't make it cost effective, which TFA itself admits.

Re:Duh (1)

ILongForDarkness (1134931) | more than 2 years ago | (#39488611)

Tilt stands on roofs are used more for people who don't have a sun facing roof though right? I suppose they might also get the angle of the panels closer to normal to the sun on average but you wouldn't be tracking the sun throughout the day right? Are they limited to areas with nice weather? The only panels I see around my area are low set to prevent wind/snow issues in the winter (80kph winds with 1m snow might not be so great for a panel on a tilt).

Re:Duh (0)

Anonymous Coward | more than 2 years ago | (#39486053)

So, in a process that surprises nobody, MIT has demonstrated that solar cells get more power when perpendicular to the angle of incoming light.

I suppose it's easier to hack the layout of the panels into some ugly modern art style than to make them less angle-dependant in the first place.
Still, just pay a little attention to your latitude and install them well and you can get most of this power boost that way. It will take more thought and planning than 'oh, just put 50 on the roof,' but most efficient work takes some planning.

Re:Duh (5, Interesting)

ILongForDarkness (1134931) | more than 2 years ago | (#39486161)

I agree about shadow effects. More comes into play though since more angles will be approximately normal to the panels more angles of light will still be in an effective region of the panel for collecting. In winter in the non-tropical regions the sun's maximum height can be pretty low in the sky giving you a very oblique angle to fixed panels against a roof (assuming a shallow slope on the roof). Making these suckers stick up means that the crossection exposed to the sun is larger even if the sun is lower in the sky.

That said two problems I see:

1) Roof top intallation will be weight. I have panels on my roof and they are about 100lb per sq yard. Stack twenty together and you'd be looking at 2000lb per sq yard. Not a good thing for the roof.

2) Ground based panels: you can put the panels on stands that can be adjusted, heck they can be motorized so they can track the sun through the day AND through the seasons. So why exactly would you by ~20X more panels (at about 200 a pop) when a $50 motor per panel (guessing), or an adjustable stand that someone goes out and tilts every month or so can have the same affect?

Re:Duh (1)

j-beda (85386) | more than 2 years ago | (#39487169)

I agree about shadow effects. More comes into play though since more angles will be approximately normal to the panels more angles of light will still be in an effective region of the panel for collecting. In winter in the non-tropical regions the sun's maximum height can be pretty low in the sky giving you a very oblique angle to fixed panels against a roof (assuming a shallow slope on the roof). Making these suckers stick up means that the crossection exposed to the sun is larger even if the sun is lower in the sky.

That said two problems I see:

1) Roof top intallation will be weight. I have panels on my roof and they are about 100lb per sq yard. Stack twenty together and you'd be looking at 2000lb per sq yard. Not a good thing for the roof.

2) Ground based panels: you can put the panels on stands that can be adjusted, heck they can be motorized so they can track the sun through the day AND through the seasons. So why exactly would you by ~20X more panels (at about 200 a pop) when a $50 motor per panel (guessing), or an adjustable stand that someone goes out and tilts every month or so can have the same affect?

Those mostly parallel my thoughts when I first read the summary. On closer reflection though, I think the investigators do have a point. The cost of the whole solar system is starting to be dominated by the non-solar-cell components. As the cost of the cells drops, new designs become more attractive. Solar panel tracking involves more than just the addition of a motor - bearings, hinges, power, maintenance, etc. are all issues that you eliminate if you don't do sun tracking for example.

If you can mass produce solar systems in a factory and minimize the work needed to install them on site - you could end up with significant overall installed costs reductions. While the weight issues may be difficult to overcome, probably twenty levels of solar cells would not weigh twenty times the weight of a single solar panel system today. The light harvesting part of the panel is an almost insignificant part of the weight of a current solar panel.

Re:Duh (0)

Anonymous Coward | more than 2 years ago | (#39487445)

The cells are still the biggest part of any install, the only thing close is installation and this would make that worse.

The whole concept is retarded. 20x as good as what??? Obviously not the ~18% efficient panels that are most of the market now.

Re:Duh (2)

semi-extrinsic (1997002) | more than 2 years ago | (#39488223)

You don't even need a motor, you can construct the tracker movement like a huge swiss clock. Some cogs, pins, belts, and a ~50 kg weight that you pull up every morning. Virtually bullet-proof, perfect in third world countries where motors are likely to be cannibalized or break down and not get repaired. (Disclaimer: not my idea, I saw someone testing such a device last summer.)

Re:Duh (1)

ILongForDarkness (1134931) | more than 2 years ago | (#39488547)

Neat idea. You'd still need to be able to tilt up and down too to account for the suns position changing with the seasons but that is a much more simple solution I think (just get someone out there to give it a nudge every month or so). Ground based solar has it pros and cons: good you can track the sun so get a bunch more power but you are tying up what otherwise might have been useful land (or alternatively have them in the middle of nowhere and have a distribution problem). Rooftop solar is nice because it uses something in a way that doesn't prevent the land from being used and is by definition in proximity to a location where power is needed. But less efficient. What we really need is solar windmills :-)

Re:Duh (1, Insightful)

gurps_npc (621217) | more than 2 years ago | (#39485963)

Same number of cells, just different configuration.

Insightful is not earned.

Re:Duh (1)

Anonymous Coward | more than 2 years ago | (#39486057)

That is not correct. Re-read the article. They are trying to qualify output per area footprint. Per unit solar cell surface area, these designs are bunk. They are just relying on the excuse that cells are cheaper than a tracking system would be.

Re:Duh (3, Funny)

93 Escort Wagon (326346) | more than 2 years ago | (#39486165)

That is not correct. Re-read the article.

"Re-" read?

Re:Duh (1)

j-beda (85386) | more than 2 years ago | (#39487205)

That is not correct. Re-read the article. They are trying to qualify output per area footprint. Per unit solar cell surface area, these designs are bunk. They are just relying on the excuse that cells are cheaper than a tracking system would be.

"Excuse" sounds a bit pejorative. If it is cheaper to stack cells then to use a tracking system, why would one want to do the later?

Re:Duh (0)

Anonymous Coward | more than 2 years ago | (#39487027)

No, same footprint. That's not the same as surface area.

They're using this as justification:

"Even 10 years ago, this idea wouldnâ(TM)t have been economically justified because the modules cost so much," Grossman says. But now, he adds, "the cost for silicon cells is a fraction of the total cost, a trend that will continue downward in the near future." Currently, up to 65 percent of the cost of photovoltaic (PV) energy is associated with installation, permission for use of land and other components besides the cells themselves.

So, yeah, assuming the cost of solar panels will continue to fall until it's below the cost of square footage to place them, then this will eventually become a better way to arrange panels.

Re:Duh (2)

The_mad_linguist (1019680) | more than 2 years ago | (#39487163)

No, they are using *significantly* more cells. Read the article. They're going by the ground footprint.

That is, the area of the earth that is being used by their solar cell array.

Let's say you have a tower ten feet high, covered in solar cells. Which is essentially what they have here. That tower is *obviously* going to have more surface area than just the amount of earth covered up by the base of the tower, since you're coating the sides as well as the top.

Re:Duh (2)

Fireking300 (1852630) | more than 2 years ago | (#39485969)

They managed to get more power out of the surface area they previously had. Sometimes you have to make do with a limited space.

Re:Duh (1)

Anonymous Coward | more than 2 years ago | (#39486253)

Surface area of the footprint, to be clear - not of the array. But the reasoning is likely as you describe. If you literally cannot spread out, you spread up. So in that respect, yes, you're increasing the efficiency of the acreage of land, but not of the array or panels themselves.

Re:Duh (1)

ceoyoyo (59147) | more than 2 years ago | (#39486113)

You read the part (in the SUMMARY) about where they were comparing collectors of equivalent area, right?

Re:Duh (1)

PIBM (588930) | more than 2 years ago | (#39486295)

same base area. I can have a more than 9000x improvement by using a (tiny) pole to install their new contraption!

Re:Duh (2)

IcyHando'Death (239387) | more than 2 years ago | (#39486387)

The summary accurately says the "same base area", i.e. footprint. This is not the panel area. The GP is underwhelmed with this announcement for good reason. This is not a breakthrough in efficiency in anything except the area required to erect the structure. It doesn't make better use of available light. It just captures more by reaching higher, making adjacent areas less valuable or even useless for further solar installations.

They suggest these towers and other configurations as useful for locations where available footprint is limited, such as urban areas. I dread the day when I start seeing such structures, erected by neighbours, looming over my fence and blocking out the sunlight to my patio, garden or my own solar collectors.

Re:Duh (1)

Imrik (148191) | more than 2 years ago | (#39487129)

If you have a fence you probably don't live in an urban area. This is more for installing on an apartment building or other tall structure than in a residential suburb.

Re:Duh (1)

djh2400 (1362925) | more than 2 years ago | (#39486205)

They also cast shadows by being raised in the air. This would effectively reduce the ground space which could be used for collecting energy. It would be interesting to see how much energy per unit of land-area is gained by using the towers vs their "2-dimensional" counterparts.

Re:Duh (1)

LordLimecat (1103839) | more than 2 years ago | (#39486987)

Theyre saying part of the increase is the fact that building vertical allows capturing more sunlight in seasons and hours when the sun is closer to the horizon. Normally those hours are colder because less sunlight is making it to the ground, due to the low angle of incidence; this mitigates some of that problem.

Its the sort of thing that seems obvious in retrospect.

Re:Duh (1)

pixelpusher220 (529617) | more than 2 years ago | (#39488047)

The problem is that this only works when these things are spaced out significantly. Which defeats the purpose of using vertical space instead of horizontal space.

Moreover, they posit that these work well at dawn/dusk. Only the outside cells works good, the rest are in shadow from the outside cell.

Or think of a city highrise landscape. You don't get any direct sun at dawn/dusk if there's something of equal height between you and the sun.

Re:Duh (1)

Maxo-Texas (864189) | more than 2 years ago | (#39488161)

A tall vertical structure is more subject to damage from extreme winds and flying objects.

Now, if it would automatically collapse flat to the ground when faced with high winds, that might mitigate the issue some.

Prior art... (3, Interesting)

msauve (701917) | more than 2 years ago | (#39485867)

So, MIT has basically recreated what a 7th grader has previously done [wattsupwiththat.com] .

Re:Prior art... (1)

mounthood (993037) | more than 2 years ago | (#39486059)

FTA:

A few other efforts — including even a middle-school science-fair project last year — have attempted 3-D arrangements of solar cells. But, Grossman says, “our study is different in nature, since it is the first to approach the problem with a systematic and predictive analysis.”

Re:Prior art... (3, Interesting)

msauve (701917) | more than 2 years ago | (#39486247)

So, the middle schooler had an idea, built it, then collected data. MIT modeled theirs first to predict behavior before building it. Meh. "Systematic and predictive analysis," that's just obfuscatory-speak.

Re:Prior art... (2)

Asic Eng (193332) | more than 2 years ago | (#39486473)

Being able to predict behavior and optimize the structure is what moves an idea from a proof of concept to something that could possibly be produced.

Re:Prior art... (0)

Anonymous Coward | more than 2 years ago | (#39486315)

Why the fuck would you link to Watts when he's just linking to slashdot? We don't need to drive pageviews to the site of some crackpot meteorology dropout.

Re:Prior art... (3, Insightful)

DerekLyons (302214) | more than 2 years ago | (#39486317)

Well, no. The 7th grader built a single physical model and made rough measurements of it's performance at a single location across a limited span of time. The MIT team built a computer model that can analyze any given configuration and simulate it's output across a wide variety of locations and wide span of time - including variations in seasonal weather patterns.

I'm not saying that what the 7th grader did wasn't cool - but he's built a pinebox derby car, while MIT has built a fully solar powered 55mph family sedan. Apples-to-oranges doesn't even *begin* to describe the differences, not only of degree but of kind, between the projects.

Re:Prior art... (3, Informative)

mutube (981006) | more than 2 years ago | (#39486419)

According to this Wired article [wired.com] the 7th graders work has been 'debunked' (or rather disproven) due to not actually testing power output but rather the 'open voltage on the circuit'. Unfortunately both the links in the Wired article point to Google webcache results that have expired so it's not possible to verify.

Link (2)

mutube (981006) | more than 2 years ago | (#39486525)

Bad form to reply to oneself, but I found the discussion of the methods I believe the article was referencing in this comment on the Watts Up With That article [wattsupwiththat.com] .

Re:Prior art... (2)

Endo13 (1000782) | more than 2 years ago | (#39486679)

Re:Prior art... (3, Informative)

Endo13 (1000782) | more than 2 years ago | (#39486953)

Apologies. Reread the GP post and realized the above links don't really deal with what he was getting at.

Here's one that's a bit more helpful, but still doesn't have all the details. It appears all the sites and cached pages are gone.
http://www.treehugger.com/clean-technology/blog-debunks-13-year-olds-solar-power-breakthrough.html [treehugger.com]

Re:Prior art... (1)

treeves (963993) | more than 2 years ago | (#39486931)

OK, that is very cool. Impressive. Need more 7th graders like that.

Big surprise (2)

O('_')O_Bush (1162487) | more than 2 years ago | (#39485877)

Big surprise that structures in volumetric configurations ended up being more efficient at gathering energy... considering plants have known this since they left the seas hundreds of millions of years ago.

Re:Big surprise (2)

demonbug (309515) | more than 2 years ago | (#39486089)

Big surprise that structures in volumetric configurations ended up being more efficient at gathering energy... considering plants have known this since they left the seas hundreds of millions of years ago.

Are you suggesting that lichen is not the evolutionary pinnacle of plant evolution? Oh sure, maybe your fancy trees produce more nutrients per unit land area, but AT WHAT COST?

paper link (4, Informative)

Trepidity (597) | more than 2 years ago | (#39485881)

As seems depressingly common in science journalism, they vaguely mentioned the existence of a paper, but don't actually give the title or (dare we hope) a hyperlink to the paper. At least they did mention the name of the journal it was published in.

In any case, the paper is "Solar energy generation in three dimensions." If you're at a university with a subscription the official version (not open-access) is here [rsc.org] . There is also an open-access preprint version at the arXiv [arxiv.org] .

Re:paper link (1)

Soulskill (1459) | more than 2 years ago | (#39486507)

Thanks, I'll add this to the summary.

But much harder to set up (5, Interesting)

Hentes (2461350) | more than 2 years ago | (#39485911)

Most people use solar panels because they can be comfortably put on rooftops. If someone has enough room for these 3D structures they could just install a Sun tracking system that's even more efficient.

Re:But much harder to set up (1)

JoeMerchant (803320) | more than 2 years ago | (#39486355)

And, what do your neighbors think about you shading their solar panels?

Re:But much harder to set up (3, Insightful)

DerekLyons (302214) | more than 2 years ago | (#39486401)

If someone has enough room for these 3D structures they could just install a Sun tracking system that's even more efficient.

Under conditions where you can see the sun - that's true. But the point of TFA is that these 3D structures are more efficient *in situations where sun trackers aren't more efficient*.

Conditions exactly like those currently outside my window - where the sky is nearly uniformly bright but you cannot see the sun at all due to the clouds. Conditions that are fairly common here in the Pacific Northwest.

Re:But much harder to set up (1)

jschen (1249578) | more than 2 years ago | (#39487463)

You don't need to see the sun to track it. Its location is predictable, so you only need to know your current location (easily determined by GPS at installation) and the current date and time.

Re:But much harder to set up (0)

DerekLyons (302214) | more than 2 years ago | (#39488455)

What part of "when you can't see the sun" and "the sky is uniformly bright" did you find so hard to understand? A sun tracker is not more efficient when there is no "brighter than average" spot in the sky to track.

Re:But much harder to set up (0)

Anonymous Coward | more than 2 years ago | (#39488833)

The point isn't that the sun is untrackable, it's that it's useless to do so since most of the light is scattered and thus not coming mostly from a single direction.

Re:But much harder to set up (2, Interesting)

Anonymous Coward | more than 2 years ago | (#39486427)

A tracker means moving parts, though; this arrangement might be cheaper and more reliable.

Costs more (2, Insightful)

AdrianKemp (1988748) | more than 2 years ago | (#39485949)

The cost/watt is higher, this is DOA I dare say.

They're simultaneously saying that it's most beneficial for northern/southern areas where daylight is diminished and that it's a more compact arrangement of cells.

Those two don't go together well... Most northern and southern areas have very large open areas due to having low overall population density.

Cost/Watt is all that matters in most areas for solar panels, Watt/weight in the rest. I can't see this being of use except in powering small devices

Re:Costs more (1)

Lehk228 (705449) | more than 2 years ago | (#39486125)

not much use right now, but possible future development of cheap / low embodied carbon / low usage of rare and toxic solar collectors with a lower collection rate could benefit from this greatly

Re:Costs more (3, Informative)

chudnall (514856) | more than 2 years ago | (#39486155)

The time is ripe for such an innovation, Grossman adds, because solar cells have become less expensive than accompanying support structures, wiring and installation. As the cost of the cells themselves continues to decline more quickly than these other costs, they say, the advantages of 3-D systems will grow accordingly.

“Even 10 years ago, this idea wouldn’t have been economically justified because the modules cost so much,” Grossman says. But now, he adds, “the cost for silicon cells is a fraction of the total cost, a trend that will continue downward in the near future.” Currently, up to 65 percent of the cost of photovoltaic (PV) energy is associated with installation, permission for use of land and other components besides the cells themselves.

Re:Costs more (1)

a-zA-Z0-9$_.+!*'(),x (1468865) | more than 2 years ago | (#39487895)

Just quoting from the article gets a score of 4????

Northern locations (1)

freeze128 (544774) | more than 2 years ago | (#39486259)

With the zigzag tower configuration, it's just more nooks and crannies for snow to collect in and block even more sunlight.

I'll wait for Zero Point Energy.

Re:Costs more (1)

ILongForDarkness (1134931) | more than 2 years ago | (#39486459)

Umm, no southern isn't southern US southern is south of the equator. While I'll give it to you that there are less people in the southern hemisphere there still is ~800M people and the land mass is much smaller (less than half), and about 20% of that is Antarctica (which presumably wouldn't be solar accessible anyways because it is in the polar region), so more dense than you'd expect I think. But still less than the northern hemisphere of course and they probably would just tear down some more rainforest rather than spend a stupidly large amount per sqm of solar panels.

Re:Costs more (0)

Anonymous Coward | more than 2 years ago | (#39486969)

Most northern and southern areas have very large open areas due to having low overall population density.

Because there are no cities or city lots in which to put solar panels in the northern/southern regions, amirite? HERP DERP DURR DURR

Re:Costs more (1)

AdrianKemp (1988748) | more than 2 years ago | (#39488581)

Yes, you are a moron.

misleading (5, Insightful)

demonbug (309515) | more than 2 years ago | (#39486021)

20x output (compared to a flat panel with the same footprint).

Not really news. This is like excitedly proclaiming that a 20 story building has nearly 20 times the floorspace of a single story building with the same footprint. Uh, no shit? (Or that a 20 story building receives more insolation than a 1-story building; hmm, you think maybe it has a lot more surface area?) I also like that they hand-wave away the fact that it costs significantly more per unit output by saying that cells are getting cheaper. Great.

Not that there aren't uses - it absolutely makes sense to go this route where you have limited footprint space - but it just doesn't seem at all revolutionary. I guess if you tack the letters M-I-T onto a press release it instantly becomes newsworthy.

Re:misleading (0)

Anonymous Coward | more than 2 years ago | (#39486169)

here, here.

Re:misleading (1)

ILongForDarkness (1134931) | more than 2 years ago | (#39486535)

Just goes to show you while Boston has Harvard, MIT and other good schools there are still dumb ideas in the city and in those schools :-) I guess stupidity obeys diffusion too :-)

Re:misleading (1)

Guspaz (556486) | more than 2 years ago | (#39487167)

By the same example, if I take a photovoltaic panel that measures 100x100x1 centimetres, and I turn it on its side, causing it to capture only, say, 50% as much energy, by their measurement (power produced versus base size) I've just increased my efficiency by 5000x... Even though I just took the panel and turned it on its side.

Yeah, I can see it being useful in some places, but there's nothing revolutionary here. It's just a novel way of mounting the existing panels.

Re:misleading (0)

Anonymous Coward | more than 2 years ago | (#39487243)

Try doing your math again. It would be 50x times as efficient (not "increased my efficiency by 5000x or even the more appropriate to your thinking "increased my efficiency by 4999x".

Re:misleading (1)

Guspaz (556486) | more than 2 years ago | (#39488641)

Sorry, you're right. Neglected to include the second dimension of the rotated panel. It doesn't change my point, though. 50x efficiency by turning the panel on its side. Which is a bit silly.

Bad title (0)

Anonymous Coward | more than 2 years ago | (#39486063)

Solar Towers are actually pretty well defined.. nor is this a Solar Power Tower, nor a Solar Furnance, or anything else.. this is just a stack of Solar Panels..

wind loading? (1)

captain_nifty (132748) | more than 2 years ago | (#39486071)

looking at their configuration all I think of is how much of a mess it will make when it blows of my roof. there's a reason people install panels flat to their roofs. not to mention the added weight and live load reaking havoc on a standard truss roof not designed for that load configuration.

Re:wind loading? (2)

sandytaru (1158959) | more than 2 years ago | (#39486257)

Ooh, now there's a configuration for you. Solar panels strapped onto the blades of a wind turbine.

It's called a TREE. (1)

EliSowash (2532508) | more than 2 years ago | (#39486099)

Someone figured out a long time ago how to build the optimal structure for turning sunlight into energy. The next step is to figure out how to get these solar arrays to utilize their own power generation to improve their performance. To grow....

Non-news (0)

Anonymous Coward | more than 2 years ago | (#39486153)

This is like saying "OMG, new invention allows many people to live on the same plot of land while still having their own space and most of the privacy they would have if they all owned their own houses... it's called... an APARTMENT BUILDING!!!"

This does not constitute news. This will not revolutionize shit. You want efficiency? Build a transparent plastic radome, (a geodesic dome transparent at the wavelength you're interested in collecting) and put a parabaloid dish inside, focus the sun's energy to the highest degree your energy collecting material of choice can tolerate, and place that where the subreflector would go, or use a Cassegrainian or pseudo (offset) Cassegranian system, with a proper subreflector, and auto-track the sun. Automatic tracking is almost trivially easy, but if you don't want to do that, you can always use math and solar astronomy to point the dish where you know the sun is going to be. The druids did it, surely we can... and that's more efficient use of PV cells (or whatever) than building a wavy-looking tower out of them.

By the way, if you don't want to move the collector, you can always create a mirror array that will track the sun, and use the array's clever layout of cells to ensure the energy always hits the stationary, ground-mounted collector, in the event you're using water instead of PV, and it turns out to be heavy.

Anyway, this is not news, please stop pretending it is.

Who killed the effecient solar array? (3, Insightful)

TraumaFox (1667643) | more than 2 years ago | (#39486163)

Quick, someone alert all of the major energy companies so they can buy up the patents and sit on them for eternity!

Re:Who killed the effecient solar array? (1)

Billy the Mountain (225541) | more than 2 years ago | (#39488825)

Citation needed

Mirrors + Molten Salt (0)

Anonymous Coward | more than 2 years ago | (#39486223)

For large scale solar to electric, the best setup is a big array of mirrors bouncing light up to a tower filled with molten salt. Excess amounts of molten salt can be stored underground. The salt is stored at very high temperatures, way above the boiling point of water. Then that heat is used to boil water and generate electricity 24 hours a day, it keeps running all night, and even for 3 or 4 cloudy days. All the technology is invented and tested. People just need to build the things out in the American southwest and start generating electricity already!

on the same size base? (1)

roberthead (932434) | more than 2 years ago | (#39486323)

In other news, a high rise building holds more people than a one story house!

Re:on the same size base? (1)

janimal (172428) | more than 2 years ago | (#39487039)

My thought exactly... the wording is similar too. eerie.

fucfk a Ho8o (-1)

Anonymous Coward | more than 2 years ago | (#39486369)

FreeBSD's Lizard - In other haapiness Another Rival distribution, int0 a sling unless

I like em.. (1)

CFBMoo1 (157453) | more than 2 years ago | (#39486457)

I live against a hill with a small wooded area. My front property is open and there's a space I could put a tower like this where the sun will hit it better then on my roof.

Dumb x 20 (0)

Anonymous Coward | more than 2 years ago | (#39486461)

Of course it will produce more power for the same base area since there are more solar cells. Sadly it doesn't improve solar cell efficiency at all. It is more like curlers (the kind worn in a woman's hair) for a house (IMHO). I wonder how it compares with the same number of solar cells in a sun tracker setup?

Good...but not enough (1)

Oceanplexian (807998) | more than 2 years ago | (#39486529)

You're still limited by physics, and ultimately even with an advanced 3D layout only so much sunlight hit's every square meter. Even if we could magically capture 100% efficiency it will never touch other forms of power generation for the same density, and will require large tracts of land for the same effect.

This is pretty neat, but a far cry from ever solving our energy crisis.

Re:Good...but not enough (1)

TheSync (5291) | more than 2 years ago | (#39487031)

You are correct that the earth receives only so much sunlight per square meter. These towers are only absorbing light that would otherwise not hit the roof - it might otherwise go into the street (where solar panels are not practical) or could be shading your neighbor's roof (where solar panels could be practical).

Re:Good...but not enough (1)

Captain Hook (923766) | more than 2 years ago | (#39489055)

it might otherwise go into the street (where solar panels are not practical)

Run a network of narrow tubes just below the surface of the road, pump water through them to draw off the heat absorbed from the sun to a heat pump of some sort to power a generator.

While I agree you might not want to do that on a major road, nothing to stop you laying it into a car park.

Re:Good...but not enough (2)

a-zA-Z0-9$_.+!*'(),x (1468865) | more than 2 years ago | (#39487941)

Actually, we get 1,000 watts from sunlight per square metre, so it would take a very minor portion of the earth's landmass to power our civilisation.

Follow nature (0)

Anonymous Coward | more than 2 years ago | (#39486875)

Tree designs, especially those requiring vast amounts of sunlight for photosynthesis, as opposed to say conifers, would seem to make a logical design template here.

Is anyone testing anything like this?

Possible uses. (0)

Anonymous Coward | more than 2 years ago | (#39486883)

The article is a bit obtuse about where its coming from, these configurations don't make the panels themselves more efficient but instead are much more standardized and have a greater energy density per unit of land/roof they take up. There are definite applications, while your cost per panel watt goes up (because you need more panels) these configurations, mass produced, could bring down installation costs considerably. Instead of having to have a roofing crew come outspend a whole day custom installing the panels on your roof, two guys stop by on one day, pour a base and run some conduit. A week later another guy or two come with the solar package, bolt it down and connect it to the base, and expand it. 8-12 hours and 6 guys reduced to 2-3 guys and 3 hours. I like the idea of the car charging stations as well, no cabling, no customized mounts, just drive up to one of these things, grab the cord and plug it into your vehicle.

Energy From Trash! (1)

Billy the Mountain (225541) | more than 2 years ago | (#39486945)

I affixed high-efficiency monocrystalline silicon PV cells to the aluminum cans and used pizza boxes strewn about in my yard and now my trash is generating electricity! Electricity from trash, wow!

Illegal because of "solar access" laws (1)

michaelmalak (91262) | more than 2 years ago | (#39486977)

In the place where this would presumably be most useful, where horizontal space is at more of a premium than vertical space, it could well be illegal due to solar access [sunschools.org] laws. Here in Denver, it has led to some odd-looking asymetric second-stories when they are added to existing bungalows -- where, say, the left half of the A-shaped roof has a shallow or near-flat slope and the right half has a steep pitch.

I'm scratching my head here (1)

Khashishi (775369) | more than 2 years ago | (#39487335)

Is there some interesting physics going on, or is this just taping a bunch of cells vertically to intercept more light at a low incidence angle? Surely,that can't be all there is to it, right?

See next post: Dysfunction In Modern Science? (1)

bussdriver (620565) | more than 2 years ago | (#39488493)

Am I the only one thinking of the next posting "Dysfunction In Modern Science?" on /. today right after this one?

Or the one a while back about a child who made a TREE with solar leaves that performed better but it turned out he had it all wrong and the media hyped the BS?

For me, in winter I have a 78 degree perpendicular with the sun-- that is nearly vertical in which case a bunch of staggered 45/-45 degree panels would work and the lower ones would get a lot of sun considering they are supposed to work fine with 10 degrees off center and the snow would reflect light towards them as well....

Problem is the sun is near 0 degrees in the summer. so half the panels would get jack.

CIGS panels handle diffuse light better; get those cheaper as many of us have more of a 2/3 cloudy year. Or IR light since most the IR light is not impacted by clouds. Or various coatings I've read about that keep more light from bouncing off the panels...

Or how about a small scale low pressure steam turbine? heat still beats out PV by a huge factor if you can extract energy from it effectively enough you can beat PV not to mention that heat storage works better than batteries.

Orientation is not so important (1)

dak664 (1992350) | more than 2 years ago | (#39488995)

Oriented or tracking panels produce only around 20-30% more energy than flat horizontal panels, when averaged over a year over most of the USA. This because much of the insolation is diffuse. NREL has maps that show the measurements at http://rredc.nrel.gov/solar/old_data/nsrdb/1961-1990/redbook/atlas/ [nrel.gov]

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