9 ms·

Covering parking lots with solar panels

111 points by zonotope 12y ago

therealdrag0 12y ago
Putting solar panels in the road/parking-lot = bad idea. But putting them over seems like a good idea from my limited knowledge.
- reitzensteinm 12y ago
  Yeah, the problem with the hype for solar roadways is that this alternative exists. Even if it were a good idea (which it isn't), this would beat it every time in terms of maintenance, energy efficiency and cost. And frankly additional benefits, shade is better than LEDs. So even if the economics works, and it doesn't, it wouldn't make sense to start with solar roadways until the carparks are all done like this, and that's a long long way away.
  - transfire 12y ago
    You are not factoring in the added savings on asphalt. Asphalt roads are expensive. For example, the new I-4 expansion in Orlando will cost $2.3 billion for 21 miles of 4 added lanes. The reason solar roadways make economical sense is because it replaces the road itself and thus adsorbs the cost of the asphalt that would otherwise have to be used. Solar canopies only make sense for parking lots and only in hot regions.
    - maxerickson 12y ago
      That $2.3 billion figure is for a lot more than the road surface.
    - Florin_Andrei 12y ago
      But aren't solar panels vastly more expensive than mere asphalt, per unit of area?
      - raisedbyninjas 12y ago
        Why yes they are. You need more than just solar panels though. You'll need thick tempered glass, power inverters, monitoring and management systems, transformers and high voltage power lines. Once installed, your glass blocks will provide the ride comfort, noise, safety, of brick or cobblestone roads but less durable and more slippery.
        Florin_Andrei 12y ago
        I seem to remember that cobblestone roads were almost as slippery as ice whenever it rained. I grew up in a town that actually had cobblestone streets (long story, Europe).
    - ams6110 12y ago
      You almost certainly still need a concrete or asphalt road bed under the panels, no?
      - mikeyouse 12y ago
        Yes. The asphalt is probably the cheapest line-item in the $2.3B budget. Not sure what OP is on about..
    - deleted 12y ago
      [deleted]
    - stephen_g 12y ago
      If there are any materials you could choose to use that are vastly more expensive than asphalt, glass and solar panels are right up high on the list. The price of a solar roadway would be staggeringly higher than a regular one. (Currently, most of the cost of roads is labour, earthworks, concrete piling, steel structures, etc.). But solar roadways are ridiculous for another reason - first, putting a solar panel under a thick layer of glass will lower its efficiency greatly - because the thickness of the glass will reduce light transmissibility through it, making the panel far less efficient than a regular one on a roof etc... Secondly, the glass is really slippery, and the only way to fix that is by texturing it or coating it in something, both which will reduce transmissibility even more. Next, if you've ever dropped an ice-cream on the road and the picked it up again, you'll know that roads are ridiculously dirty. The dirt and grime will build up, just like regular roads, reducing the efficiency even more. Then, the cars driving over it will grind that dust into the glass, and any abarasive material will put tiny scratches in the panel - which over time will build up and again reduce efficiency further. Dave Jones from the Electronics Engineering Video Blog (EEVBlog) did some calculations in one of his videos - assuming optimal efficiency. Even then, a panel would not make enough electricity to pay itself back (can't remember the time period exactly - over 20 or 30 years? Or perhaps it was the estimated lifetime of a panel). But with all these extra losses, there is no way it would ever work without huge advances in solar technology and materials science.
  - mapt 12y ago
    You are 100% correct, but it begs an addition: Industrial-scale rural solar power would beat this every time in the same metrics. Land isn't a scarce element of solar power - and transmission is cheap.
freehunter 12y ago
A major Midwest software company near me has these over their visitor lot (their employee lot being underground), and has a huge farm of solar panels behind the building. I think it's a great idea. On the graph at the bottom, does anyone know why the estimation goes down after 2016, then only slightly rises in 2018? There has to be some reason why solar installs would take a major hit like that, but I didn't see it explained in the article.
- maxerickson 12y ago
  The source of the chart data is linked just above it. GTM Research forecasts that the market will continue to grow year-over-year until the drop-off in the federal ITC, peaking at 318 megawatts in 2016 The federal ITC is a tax credit.
mixedmath 12y ago
I'm not too aware of payback timeframes and maintenance costs of solar power. So I thought I would look into the Rutgers solar canopy. This led me to the news article at Rutgers discussing the project: http://news.rutgers.edu/news-releases/2011/04/rutgers-board-of-gov-20110405#.VMv_7VWJOuY http://news.rutgers.edu/news-releases/2011/04/rutgers-board-... The description largely matches this article in the Washington Post. It also mentions that it was a "40.8 million dollar project." I'm uncertain if this includes various tax breaks and incentives, but let's take it at face value. It also mentions that it will generate 1.2 million dollars per year in electricity. If we assume that electricity costs will stay perfectly constant and that maintenance costs are factored into the 40.8 million, this means the facility would pay for itself in 34 years. I do not actually expect maintenance to be included. I ask myself, how long does a solar panel actually last? It seems many tariffs and incentives are based on a 25 year life of a solar panel. The UK Centre for Alternative Technology has the following article: http://info.cat.org.uk/questions/pv/life-expectancy-solar-PV-panels http://info.cat.org.uk/questions/pv/life-expectancy-solar-PV... In it, they explain that a solar panel's output will go down by about 1% per year. The materials surrounding the electricity production will wear, yellow, or otherwise decay, but the power production seems largely unaffected for 30 or more years (aside from the 1% decrease each year, that is). On the flipside, energy costs are rising at much more than 1% a year. So in terms of raw energy pricing, and assuming that maintenance isn't too much of an issue, it seems like the Rutgers facility might "pay for itself" in 35 years. Of course, it isn't exactly a good fiscal decision to freeze $40 million dollars for 40 years. I have no idea how to quantify the benefits of shade for the cars. But overall I now have a basic understanding of why someone might build the Rutgers facility. It also seems likely that as energy costs rise, solar panels become less expensive and more efficient, then these canopies will make much more financial sense. It seems like it would take a lot for it to be a "good money investment" though.
- deleted 12y ago
  [deleted]
- saalweachter 12y ago
  I also have no idea how to quantify the benefits of shade for cars, but want to point out that they're non-negligible. Everything ages faster when exposed to sunlight and heat -- your paints will fade, the rubber bits will lose their flexibility and crack, your vinyl seats will slowly evaporate. There should be a measurable difference in how long a shaded car lasts versus an exposed car and a savings for taking better care of your car.
lifeisstillgood 12y ago
This strikes me as the perfect political investment. It passes the "new one on me" test, and it passes the "green is hip" test, and it would be a constant reminder of the politicians involved (ala Boris Bikes for Londoners). It also promises to kick start a maintenance industry and lower costs as stnadrds are formed. Overall I would expect this one to be subsidised and persued more hungrily than any offshore projects or windfarms
- dogwelder 12y ago
  In Europe and Asia, I'd expect so. In the States, fossil fuel interests have already mobilized their media campaign, pushing for new taxes to penalize local solar energy generation. They've had some victories and some losses, but as another poster mentioned, they don't have to win every battle - just enough to sow uncertainty on whether it'll be a good investment.
jmadsen 12y ago
Here in Japan, virtually ALL parking in lots is hourly metered. You get a ticket & if you spend money in the stores, they will credit you the price of the parking (making it cheap or free for actual paying customers) on the ticket. This is actually done for reasons of space - cities are crowded & and space for parking is at a premium. The result is that it is just considered normal. In the US, they have these massive lots that are spread out over an area often larger than the store itself. The obvious thing to do would charge for parking with the Japanese system, and use the proceeds to help offset the initial costs, just like with a toll highway or bridge. However, the "God-given Right to Free Parking" mentality would never allow it to work, and the local governments are too weak to try to impose it. Every city has a ring of malls outside of it not just for cheaper land, but to escape any form of regulations from the city itself. This is a "risky thing", and businesses don't like risk. It would take a very careful marketing campaign to be able to kickstart something like this. I doubt many places have the leadership required.
- ams6110 12y ago
  The lots are privately owned by the malls, shopping centers, or stores. The "city" is in no position to impose paid parking on private property. Where parking is scarce, private parking is generally not free. Where parking is provided on public property (e.g. city streets) it is often metered, though certainly not always.
  - jmadsen 12y ago
    While they can't directly tell a mall "you have to charge", they can encourage it indirectly through zoning laws: For example, they can cap the footprint of parking lot space, leading to stores building parking garages or taking their own steps to minimize freeloaders through metering. That's just an off the top of my head example. Never say the govt "can't do something". The have power of eminent domain, as an example of how far they are able to go when the actual will is there to have something they want. Check out the history of the new Fenway Park for things they can do.
    - crisnoble 12y ago
forgotAgain 12y ago
Our local government has leased the rights to build solar panels over their parking lots to a private sector company. They've covered most lots at this time. The panels have all of the advantages outlined in the article. The only downside not mentioned was snow and ice falling from the overhead panels. At least one person has been hurt.
uptown 12y ago
Despite all the positives - not everybody is a fan of these. This is a battle being waged in Connecticut over solar carports: http://www.fairfieldcitizenonline.com/news/article/Neighbors-lawsuit-aims-to-pull-the-plug-on-6029470.php http://www.fairfieldcitizenonline.com/news/article/Neighbors...
- kalleboo 12y ago
  That sounds more like someone is sour over their own zoning permit being denied than any actual opposition to the panels themselves.
  - maxerickson 12y ago
    I think the panels might block the road visibility of his business (which I don't have a lot of sympathy for, but it's at least a less petty motivation).
phamilton 12y ago
Our local high school (bay area) has solar panels over the parking lot. Seems to be working out.
dba7dba 12y ago
This seems to be a much better option than setting up large solar farms in the middle of the CA desert. Parking lots are eyesores anyway so cover them up with solar panels. Why ruin pristine nature with solar panels.
- thrownaway2424 12y ago
  The difference is the deserts get serious insolation. Or put another way, the places with major sunshine do not also contain major cities. Another problem with cities is the structures shade the panels.
  - tracker1 12y ago
    Depends on the cities... here in the Phoenix area most of the buildings are only 1-2 stories.. and most of the larger parking lots don't get any shade from the buildings... There are several of these covered lots here in Phoenix, and more going up. A lot of places have covered parking anyway, so throwing solar panels on them isn't that much more cost in labor, and payoff in 8-12 years usually, with some profites for 5-15 after (at least from the costs of the past decade as a forcast).
  - dba7dba 12y ago
    There's hardly any 'desert' near major cities with skyscrapers. Maybe LA but still nothing like NY. IMO putting serious money into solar panels anywhere other than sun belt of US is waste of money.
_almosnow 12y ago
This is nice but this is also 99.99% of solar related energy "solutions". If we put <some solar tech> in <some place> we could generate enough energy to power <many things>; however it is still not cost-effective to do so.
- _almosnow 12y ago
  Yeah right... this is not true at all.
fernly 12y ago
Ever since I first saw one of these -- several years ago, near the Googleplex [1] -- I have had this idea for a real-estate venture. You're welcome to take it on, because I'll never get around to it. Step 1, go into AZ, somewhere not too far from Phoenix or Tucson, buy some cheap desert land near a freeway exit. Step 2, grade the land and gravel it, never mind asphalt, no need. Step 3, good high security fence around. Step 4, Put up solar panels like these, but raised good and high, 20ft clearance under. Step 5, advertise "Shaded RV Storage". Charge people a good rate for storing their RVs where they will not be so horribly sun-damaged, as many RVs are damaged by long-term sun exposure. Meanwhile selling power to the utility. And, bonus, put gutters along the lower edge of the tilted panels, leading to a buried cistern, collect rainwater water for pretty landscaping and for washing RVs (for a fee, your RV will be all sparkly clean when you come pick it up). Yer welcome. [1] Street view https://goo.gl/maps/2T8mZ https://goo.gl/maps/2T8mZ
- kenrikm 12y ago
  Feasible? https://www.youtube.com/watch?v=HOZBrHqTJk4 https://www.youtube.com/watch?v=HOZBrHqTJk4
  - tracker1 12y ago
    In the gp's post, he's talking about above ground mounting, similar to rooftop, and more like the parking lot coverage in tfa... in this case it's actually about a break even for the solar in 8-12 years usually... (feel good qualities not withstanding)... that covers the electrical usage for the lot's residents, at the very least. Assuming you are charging for the electricity... you are still making the lot rent, and on top of that, you can charge more for being a "green" lot (if the organic food market is any indication), which means you can charge over 20-30% more than standard lots... so your break even on investment is about 8-12 years, but you'll be making 20-30% more on the lot rent, which means you'll probably break even much sooner, and see a close to pure profit for 8-10 years after the investment paid for itself. It's not a bad system... this also doesn't account for states like Arizona and California that offer tax breaks and incentives for solar initiatives like this one.
- baddox 12y ago
the8472 12y ago
> Asphalt and concrete absorb the sun’s energy, retaining heat — and contributing to the “urban heat island effect,” in which cities are hotter than the surrounding areas. If the solar cells were coated with some layer that reflects all the photons that can't be harvested for electricity that might mitigate that problem even further Or maybe they already are?
- benplumley 12y ago
  - All heat not reflected is absorbed. - Solar panels operate more efficiently at lower temperatures. [1] Based on these facts, I'd venture to guess that your idea is already being worked on. [1] http://homeguides.sfgate.com/effects-temperature-solar-panel-power-production-79764.html http://homeguides.sfgate.com/effects-temperature-solar-panel...
- baq 12y ago
  most are black because that's what absorbs photons. asphalt happens to be black, but it converts 100% of captured energy into heat, whereas PV systems decrease that value to 95-50% (source: http://en.wikipedia.org/wiki/Solar_cell_efficiency#mediaviewer/File:PVeff(rev141208).jpg http://en.wikipedia.org/wiki/Solar_cell_efficiency#mediaview...)
  - the8472 12y ago
    They're black in visible light. But as far as I know they cannot harvest IR photons. So it would probably be useful if they reflected IR. Although I don't know if it's better for them to be reflective or black in the IR window where where atmosphere is transparent. Black makes for good emitters too and that way they could shed heat into space. If we could arbitrarily designed reflectivity vs. transparency it would probably be transparent in visible, reflective in IR, black in the IR window
stretchwithme 12y ago
I sure hope such investments have enough time to make their money back. I expect robotic cars to do away with the need to own personal cars. Shared by many people, a robotic cab will spend a lot less time sitting around and many parking lots will disappear.
rottyguy 12y ago
I was in Qatar this summer and noticed them. Anyone know how long this has been installed there? http://www.qf.org.qa/content/the-foundation/issue-68/qatars-new-energy-horizons http://www.qf.org.qa/content/the-foundation/issue-68/qatars-... QF’s solar project has also brought parking lot shades covered in solar panels to Education City – the first in Qatar – and achieved the first agreement to be signed by Qatar General Electricity and Water Corporation (KAHRAMAA) that accepts a private commercial energy project’s connection to Qatar’s central power grid. looks like the following company has been providing this type of construction since, at least, 2012 when this article was published (the company looks like it's been around since 2006). http://envisionsolar.com/press-releases/envision-solar-announces-business-development-initiatives-in-united-arab-emirates-qatar-and-spain/ http://envisionsolar.com/press-releases/envision-solar-annou...

111 points by zonotope 12y ago

Putting solar panels in the road/parking-lot = bad idea. But putting them over seems like a good idea from my limited knowledge.

reitzensteinm 12y ago
Yeah, the problem with the hype for solar roadways is that this alternative exists. Even if it were a good idea (which it isn't), this would beat it every time in terms of maintenance, energy efficiency and cost. And frankly additional benefits, shade is better than LEDs. So even if the economics works, and it doesn't, it wouldn't make sense to start with solar roadways until the carparks are all done like this, and that's a long long way away.
- transfire 12y ago
  You are not factoring in the added savings on asphalt. Asphalt roads are expensive. For example, the new I-4 expansion in Orlando will cost $2.3 billion for 21 miles of 4 added lanes. The reason solar roadways make economical sense is because it replaces the road itself and thus adsorbs the cost of the asphalt that would otherwise have to be used. Solar canopies only make sense for parking lots and only in hot regions.
  - maxerickson 12y ago
    That $2.3 billion figure is for a lot more than the road surface.
  - Florin_Andrei 12y ago
    But aren't solar panels vastly more expensive than mere asphalt, per unit of area?
    - raisedbyninjas 12y ago
      Why yes they are. You need more than just solar panels though. You'll need thick tempered glass, power inverters, monitoring and management systems, transformers and high voltage power lines. Once installed, your glass blocks will provide the ride comfort, noise, safety, of brick or cobblestone roads but less durable and more slippery.
      - Florin_Andrei 12y ago
        I seem to remember that cobblestone roads were almost as slippery as ice whenever it rained. I grew up in a town that actually had cobblestone streets (long story, Europe).
  - ams6110 12y ago
    You almost certainly still need a concrete or asphalt road bed under the panels, no?
    - mikeyouse 12y ago
      Yes. The asphalt is probably the cheapest line-item in the $2.3B budget. Not sure what OP is on about..
  - deleted 12y ago
    [deleted]
  - stephen_g 12y ago
    If there are any materials you could choose to use that are vastly more expensive than asphalt, glass and solar panels are right up high on the list. The price of a solar roadway would be staggeringly higher than a regular one. (Currently, most of the cost of roads is labour, earthworks, concrete piling, steel structures, etc.). But solar roadways are ridiculous for another reason - first, putting a solar panel under a thick layer of glass will lower its efficiency greatly - because the thickness of the glass will reduce light transmissibility through it, making the panel far less efficient than a regular one on a roof etc... Secondly, the glass is really slippery, and the only way to fix that is by texturing it or coating it in something, both which will reduce transmissibility even more. Next, if you've ever dropped an ice-cream on the road and the picked it up again, you'll know that roads are ridiculously dirty. The dirt and grime will build up, just like regular roads, reducing the efficiency even more. Then, the cars driving over it will grind that dust into the glass, and any abarasive material will put tiny scratches in the panel - which over time will build up and again reduce efficiency further. Dave Jones from the Electronics Engineering Video Blog (EEVBlog) did some calculations in one of his videos - assuming optimal efficiency. Even then, a panel would not make enough electricity to pay itself back (can't remember the time period exactly - over 20 or 30 years? Or perhaps it was the estimated lifetime of a panel). But with all these extra losses, there is no way it would ever work without huge advances in solar technology and materials science.
- mapt 12y ago
  You are 100% correct, but it begs an addition: Industrial-scale rural solar power would beat this every time in the same metrics. Land isn't a scarce element of solar power - and transmission is cheap.

freehunter 12y ago

A major Midwest software company near me has these over their visitor lot (their employee lot being underground), and has a huge farm of solar panels behind the building. I think it's a great idea. On the graph at the bottom, does anyone know why the estimation goes down after 2016, then only slightly rises in 2018? There has to be some reason why solar installs would take a major hit like that, but I didn't see it explained in the article.

maxerickson 12y ago
The source of the chart data is linked just above it. GTM Research forecasts that the market will continue to grow year-over-year until the drop-off in the federal ITC, peaking at 318 megawatts in 2016 The federal ITC is a tax credit.

mixedmath 12y ago

I'm not too aware of payback timeframes and maintenance costs of solar power. So I thought I would look into the Rutgers solar canopy. This led me to the news article at Rutgers discussing the project: http://news.rutgers.edu/news-releases/2011/04/rutgers-board-of-gov-20110405#.VMv_7VWJOuY http://news.rutgers.edu/news-releases/2011/04/rutgers-board-... The description largely matches this article in the Washington Post. It also mentions that it was a "40.8 million dollar project." I'm uncertain if this includes various tax breaks and incentives, but let's take it at face value. It also mentions that it will generate 1.2 million dollars per year in electricity. If we assume that electricity costs will stay perfectly constant and that maintenance costs are factored into the 40.8 million, this means the facility would pay for itself in 34 years. I do not actually expect maintenance to be included. I ask myself, how long does a solar panel actually last? It seems many tariffs and incentives are based on a 25 year life of a solar panel. The UK Centre for Alternative Technology has the following article: http://info.cat.org.uk/questions/pv/life-expectancy-solar-PV-panels http://info.cat.org.uk/questions/pv/life-expectancy-solar-PV... In it, they explain that a solar panel's output will go down by about 1% per year. The materials surrounding the electricity production will wear, yellow, or otherwise decay, but the power production seems largely unaffected for 30 or more years (aside from the 1% decrease each year, that is). On the flipside, energy costs are rising at much more than 1% a year. So in terms of raw energy pricing, and assuming that maintenance isn't too much of an issue, it seems like the Rutgers facility might "pay for itself" in 35 years. Of course, it isn't exactly a good fiscal decision to freeze $40 million dollars for 40 years. I have no idea how to quantify the benefits of shade for the cars. But overall I now have a basic understanding of why someone might build the Rutgers facility. It also seems likely that as energy costs rise, solar panels become less expensive and more efficient, then these canopies will make much more financial sense. It seems like it would take a lot for it to be a "good money investment" though.

deleted 12y ago
[deleted]
saalweachter 12y ago
I also have no idea how to quantify the benefits of shade for cars, but want to point out that they're non-negligible. Everything ages faster when exposed to sunlight and heat -- your paints will fade, the rubber bits will lose their flexibility and crack, your vinyl seats will slowly evaporate. There should be a measurable difference in how long a shaded car lasts versus an exposed car and a savings for taking better care of your car.

lifeisstillgood 12y ago

This strikes me as the perfect political investment. It passes the "new one on me" test, and it passes the "green is hip" test, and it would be a constant reminder of the politicians involved (ala Boris Bikes for Londoners). It also promises to kick start a maintenance industry and lower costs as stnadrds are formed. Overall I would expect this one to be subsidised and persued more hungrily than any offshore projects or windfarms

dogwelder 12y ago
In Europe and Asia, I'd expect so. In the States, fossil fuel interests have already mobilized their media campaign, pushing for new taxes to penalize local solar energy generation. They've had some victories and some losses, but as another poster mentioned, they don't have to win every battle - just enough to sow uncertainty on whether it'll be a good investment.

jmadsen 12y ago

Here in Japan, virtually ALL parking in lots is hourly metered. You get a ticket & if you spend money in the stores, they will credit you the price of the parking (making it cheap or free for actual paying customers) on the ticket. This is actually done for reasons of space - cities are crowded & and space for parking is at a premium. The result is that it is just considered normal. In the US, they have these massive lots that are spread out over an area often larger than the store itself. The obvious thing to do would charge for parking with the Japanese system, and use the proceeds to help offset the initial costs, just like with a toll highway or bridge. However, the "God-given Right to Free Parking" mentality would never allow it to work, and the local governments are too weak to try to impose it. Every city has a ring of malls outside of it not just for cheaper land, but to escape any form of regulations from the city itself. This is a "risky thing", and businesses don't like risk. It would take a very careful marketing campaign to be able to kickstart something like this. I doubt many places have the leadership required.

ams6110 12y ago
The lots are privately owned by the malls, shopping centers, or stores. The "city" is in no position to impose paid parking on private property. Where parking is scarce, private parking is generally not free. Where parking is provided on public property (e.g. city streets) it is often metered, though certainly not always.
- jmadsen 12y ago
  While they can't directly tell a mall "you have to charge", they can encourage it indirectly through zoning laws: For example, they can cap the footprint of parking lot space, leading to stores building parking garages or taking their own steps to minimize freeloaders through metering. That's just an off the top of my head example. Never say the govt "can't do something". The have power of eminent domain, as an example of how far they are able to go when the actual will is there to have something they want. Check out the history of the new Fenway Park for things they can do.
  - crisnoble 12y ago

forgotAgain 12y ago

Our local government has leased the rights to build solar panels over their parking lots to a private sector company. They've covered most lots at this time. The panels have all of the advantages outlined in the article. The only downside not mentioned was snow and ice falling from the overhead panels. At least one person has been hurt.

uptown 12y ago

Despite all the positives - not everybody is a fan of these. This is a battle being waged in Connecticut over solar carports: http://www.fairfieldcitizenonline.com/news/article/Neighbors-lawsuit-aims-to-pull-the-plug-on-6029470.php http://www.fairfieldcitizenonline.com/news/article/Neighbors...

kalleboo 12y ago
That sounds more like someone is sour over their own zoning permit being denied than any actual opposition to the panels themselves.
- maxerickson 12y ago
  I think the panels might block the road visibility of his business (which I don't have a lot of sympathy for, but it's at least a less petty motivation).

phamilton 12y ago

Our local high school (bay area) has solar panels over the parking lot. Seems to be working out.

dba7dba 12y ago

This seems to be a much better option than setting up large solar farms in the middle of the CA desert. Parking lots are eyesores anyway so cover them up with solar panels. Why ruin pristine nature with solar panels.

thrownaway2424 12y ago
The difference is the deserts get serious insolation. Or put another way, the places with major sunshine do not also contain major cities. Another problem with cities is the structures shade the panels.
- tracker1 12y ago
  Depends on the cities... here in the Phoenix area most of the buildings are only 1-2 stories.. and most of the larger parking lots don't get any shade from the buildings... There are several of these covered lots here in Phoenix, and more going up. A lot of places have covered parking anyway, so throwing solar panels on them isn't that much more cost in labor, and payoff in 8-12 years usually, with some profites for 5-15 after (at least from the costs of the past decade as a forcast).
- dba7dba 12y ago
  There's hardly any 'desert' near major cities with skyscrapers. Maybe LA but still nothing like NY. IMO putting serious money into solar panels anywhere other than sun belt of US is waste of money.

_almosnow 12y ago

This is nice but this is also 99.99% of solar related energy "solutions". If we put <some solar tech> in <some place> we could generate enough energy to power <many things>; however it is still not cost-effective to do so.

_almosnow 12y ago
Yeah right... this is not true at all.

fernly 12y ago

Ever since I first saw one of these -- several years ago, near the Googleplex [1] -- I have had this idea for a real-estate venture. You're welcome to take it on, because I'll never get around to it. Step 1, go into AZ, somewhere not too far from Phoenix or Tucson, buy some cheap desert land near a freeway exit. Step 2, grade the land and gravel it, never mind asphalt, no need. Step 3, good high security fence around. Step 4, Put up solar panels like these, but raised good and high, 20ft clearance under. Step 5, advertise "Shaded RV Storage". Charge people a good rate for storing their RVs where they will not be so horribly sun-damaged, as many RVs are damaged by long-term sun exposure. Meanwhile selling power to the utility. And, bonus, put gutters along the lower edge of the tilted panels, leading to a buried cistern, collect rainwater water for pretty landscaping and for washing RVs (for a fee, your RV will be all sparkly clean when you come pick it up). Yer welcome. [1] Street view https://goo.gl/maps/2T8mZ https://goo.gl/maps/2T8mZ

kenrikm 12y ago
Feasible? https://www.youtube.com/watch?v=HOZBrHqTJk4 https://www.youtube.com/watch?v=HOZBrHqTJk4
- tracker1 12y ago
  In the gp's post, he's talking about above ground mounting, similar to rooftop, and more like the parking lot coverage in tfa... in this case it's actually about a break even for the solar in 8-12 years usually... (feel good qualities not withstanding)... that covers the electrical usage for the lot's residents, at the very least. Assuming you are charging for the electricity... you are still making the lot rent, and on top of that, you can charge more for being a "green" lot (if the organic food market is any indication), which means you can charge over 20-30% more than standard lots... so your break even on investment is about 8-12 years, but you'll be making 20-30% more on the lot rent, which means you'll probably break even much sooner, and see a close to pure profit for 8-10 years after the investment paid for itself. It's not a bad system... this also doesn't account for states like Arizona and California that offer tax breaks and incentives for solar initiatives like this one.
baddox 12y ago

the8472 12y ago

> Asphalt and concrete absorb the sun’s energy, retaining heat — and contributing to the “urban heat island effect,” in which cities are hotter than the surrounding areas. If the solar cells were coated with some layer that reflects all the photons that can't be harvested for electricity that might mitigate that problem even further Or maybe they already are?

benplumley 12y ago
- All heat not reflected is absorbed. - Solar panels operate more efficiently at lower temperatures. [1] Based on these facts, I'd venture to guess that your idea is already being worked on. [1] http://homeguides.sfgate.com/effects-temperature-solar-panel-power-production-79764.html http://homeguides.sfgate.com/effects-temperature-solar-panel...
baq 12y ago
most are black because that's what absorbs photons. asphalt happens to be black, but it converts 100% of captured energy into heat, whereas PV systems decrease that value to 95-50% (source: http://en.wikipedia.org/wiki/Solar_cell_efficiency#mediaviewer/File:PVeff(rev141208).jpg http://en.wikipedia.org/wiki/Solar_cell_efficiency#mediaview...)
- the8472 12y ago
  They're black in visible light. But as far as I know they cannot harvest IR photons. So it would probably be useful if they reflected IR. Although I don't know if it's better for them to be reflective or black in the IR window where where atmosphere is transparent. Black makes for good emitters too and that way they could shed heat into space. If we could arbitrarily designed reflectivity vs. transparency it would probably be transparent in visible, reflective in IR, black in the IR window

stretchwithme 12y ago

I sure hope such investments have enough time to make their money back. I expect robotic cars to do away with the need to own personal cars. Shared by many people, a robotic cab will spend a lot less time sitting around and many parking lots will disappear.

rottyguy 12y ago

I was in Qatar this summer and noticed them. Anyone know how long this has been installed there? http://www.qf.org.qa/content/the-foundation/issue-68/qatars-new-energy-horizons http://www.qf.org.qa/content/the-foundation/issue-68/qatars-... QF’s solar project has also brought parking lot shades covered in solar panels to Education City – the first in Qatar – and achieved the first agreement to be signed by Qatar General Electricity and Water Corporation (KAHRAMAA) that accepts a private commercial energy project’s connection to Qatar’s central power grid. looks like the following company has been providing this type of construction since, at least, 2012 when this article was published (the company looks like it's been around since 2006). http://envisionsolar.com/press-releases/envision-solar-announces-business-development-initiatives-in-united-arab-emirates-qatar-and-spain/ http://envisionsolar.com/press-releases/envision-solar-annou...