Is it practical to generate all US power by solar PV?

[Salvador]

It's hard for me to follow you Jim especially with all those BTU's and stuff I'm not sure if it's the SI system or the older one that the US uses.

https://en.wikipedia.org/wiki/International_System_of_Units#/media/File:SI-metrication-world.png

P.S. I wonder if the American settlers so hated the imperialistic British empire then why did you kept their old measurement system.I think the SI system is easier , yes I know it's a biased opinion but still it feels easier, much like I would love the world to speak just one language and I have to admit English is the easiest for me , so many problems would go away and we could make progress faster.

As for the heat pump I got the main point , well you can always use a solar panel to be your " excitation" power source together with a few wind blades in case sun doesn't shine usually wind blows then.You can use that electricity to power your low power applications and leave the rest for the heat pumps motor and then the heat pump takes the high power applications replacing them with natural heat from earth.After all the most consuming electrical applications nowdays are the ones that have to produce heat , like electric heating, ovens and cooking stuff , water heaters etc.Basically everything with a large resistor inside.
Maybe it's not so much of a problem for you if you live in warm climate but where I live we still get winters , much different than the ones my grandmother used to recall so I can confirm climate is changing but they are still there so in winter almost 3/4 if not more of my bill go for heating.
And since I have an electrical water heater that part goes around the year.So basically most of my electricity bill is for heat.

I agree with what one of you said earlier that we must diversify the renewables , not because it's simpler no it's not , it's more complicated , also it's not cheaper but it's simply because with renewables you don't get enough power out to simply take one and leave it there , it's not a nuke plant that gets the job done for a middle sized city easily.So we must use many different alternatives that all give us the same end result.

P.S. when I write the word renewables the system puts a red line underneath the word but I checked and I think I'm writing it correctly so what's wrong with the red line ?
Could it be that physics forums software isn't friendly to renewables ? :D:D Whenever I write words like big nuclear plant or fossil fuels they aren't labeled red :D

 

[jim hardy]

(post 126)
Jim, your reference price includes installation, inverters, the works. I don't think $1 per W includes installation.

Yes, the dollar a watt was for just a panel , for DoItYourself-ers.

Bauncore i think said $1Au in his part of the world included installation.

As far as i can tell, the cited cost where i live includes your tax credits and gov't incentives, so up-front out of pocket cost is likely a lot higher. In Florida i inquired about a "free" solar system. Yeah, $6000 now to them and "You'll get it all back when you file your taxes" . Buyer beware.
old jim

 

[jim hardy]

It's hard for me to follow you Jim especially with all those BTU's and stuff I'm not sure if it's the SI system or the older one that the US uses.

Sorry for that

i hope i didnt drop a conversion factor someplace
A BTU is the heat to warm one pound of water by 1 degree F ...
so it's a unit of energy just like a joule.
in terms of F X D it's 778 foot pounds
which should be easy to convert to SI,
using estimates from our everyday experience
we know from a coffee can that a pound is 0.454kg,
and we remember from Physics class that 9.8 gets us from kg to Newtons (edit at standard gravity)...
Does a "Quarter Pounder" hamburger weigh around a Newton ? Maybe 1.1 Newtons ?

that's why Electrical Engineering is easy and Mechanical Engineering is difficult - our units are already metric, Volts Amps Ohms, Joules and Watts.
I always pitied Mechanical engineers for their Ohm's Law requires square roots and Reynolds numbers.

That's why long ago i latched on to these two memory aids
"A BTU per second is within 5% of a kilowatt"
and in power plants where we produce and track heat but sell it as electrical energy ,
" 3412.7 BTU's = 1kwh" is as basic as gravity.

from those memory aids and 2.54 cm to the inch one can figure out any other units

and that's what EER rating does for people, converts units
tells how many BTU's a heat pump moves per watt-hour. That's units of energy moved per unit of energy put in.
And you don't have to be a physicist to know 10 is so-so, twenty is great and 5 is terrible.

With so many units named after long gone scientists it is difficult to keep straight whether one is describing energy or power.
I understand your plight, been there and still stumble especially if I'm trying to hurry.

If i made a mistake please point it out and i'll correct it.

old jim

 

[anorlunda]

I come from a place were all the basic infrastructure when it first arrived as technology in the first half of the 20th century was entirely built by special state run agencies.Everything from the biggest nuke plants to hydro to the last pole with three phases running into your house was entirely state controlled as it was seen as something strategically important and so not to be given to any private companies

I think you are confusing ownership with source of financing. If you go back and check the history of those government project you mention, I'm confident that you will find that they were largely financed with bond sales to private investors.

It was those private investors that I referred to in #118. They were not compelled to buy the bonds, and if they did not believe in the projects they would have put their money elsewhere.

In 1983, Washington Public Power System (WPPS which I pronounce as "whoops") defaulted on their municipal bonds for the Satsop Nuclear Power Plant. In the USA, that event changed forever the scrutiny given to government utility bonds. A portfolio manager could be guilty of malpractice if he invested private money in government bonds for an unsound project. It happens every day that proposed projects are canceled because they fail to attract sufficient financing. Those cancellations may make no news or are reported in an obscure item on page 22c of the newspaper.

I stand by what I said. Large scale electric infrastructure projects. public or private, require private money to finance them. The private investors have the final say over whether to invest their money or not.

There may be TVA or BPA employees reading this thread. Perhaps they could tell us if their organizations do or don't raise money selling bonds.

 

[IllyaKuryakin]

Quite simply, no, we can't produce all our power with PV. The reason is that the sun doesn't shine at night and there is no practical way to store enough power to get us though the night. The efficient combined cycle power plants or nuclear plants take days to start up, so they can't even be shut down during the day when the sun does shine and provide needed power at night. All PV can do is offset the "Peak" power plants that start up quickly to provide peak power demands during the day. That amounts to no more than 10% of total power production.

 

[nikkkom]

Quite simply, no, we can't produce all our power with PV. The reason is that the sun doesn't shine at night and there is no practical way to store enough power to get us though the night.

No, there are many ways to store energy. Some are in use even in todays power grid.

 

[IllyaKuryakin]

No, there are many ways to store energy. Some are in use even in todays power grid.

Yes, I agree, there are many ways to store energy, but none can cost effectively store the amount of energy needed to get us through the night. Sorry, that's just a fact. Do a bit of research into the matter as I have and I'm sure you will reach the same conclusion. Now, if you create a cost effective way to store vast amounts of electrical energy, not only will we be able to use PV to generate all our power, but you may become the worlds first multi-trillionaire. So, I'll be very nice to you, just in case you are successful :-)

 

[nikkkom]

Yes, I agree, there are many ways to store energy, but none can cost effectively store the amount of energy needed to get us through the night. Sorry, that's just a fact.

Cost-effectively? This thread's title is not "Can battery-backed energy storage be on par with current coal and gas plants?"

I am sure it would be more expensive. The question is whether it's practically possible (and I might add, without drastic measures such as diverting entire world's lithium production into batteries production for decades, or making electricity permanently x20 more expensive, or something like that).

Looks like it is possible. Many battery types exist, we are not limited to expensive lightweight ones. Sodium-Ion, good old Lead-Acid, Sodium-sulfur, Ni-Cd, Al-ion. New types of batteries are being looked at.

Even now people build huge batteries, such as 400MWh, and not because they are nuts and want to build something uneconomic. Evidently, it is _profitable_:
http://www.utilitydive.com/news/5-battery-energy-storage-projects-to-watch-in-2016/409624/

 

[bob012345]

In another PF thread it was proposed to build a centralized PV farm of 1000 gigawatts , which is the order of magnitude of US installed generating capacity. It'd cover 1/10 the area of New Mexico, Arizona and Nevada.

√ (10%of 896815 km^2) = 299.5 km per side, 186 miles per side, not far from the 150 stated earlier in the same thread.
Close enough for thought experiments.

You can't drive maintenance trucks over solar panels so the dimensions will expand to accommodate roadways.
Unless they're elevated to serve as rooftops with access from below.
Stormwater runoff from a 150 mile square rooftop will be a challenge, Phoenix area has been known to get 6 inches in a storm.
http://www.fcd.maricopa.gov/Weather/Rainfall/raininfo.aspx

It'd be interesting that's for sure.
Myself, i am far more afraid of huge storage batteries than of reactors. I wouldn't be go anywhere near them.

Maybe @anorlunda will assess the practicality of moving so much power over so much distance.

The answer is no. It is not practical nor wise to embark on such a massive project which assumes natural solar is the best and only solution, which it is not. Encourage development with tax policy and let the markets decide how to provide power.

 

[mheslep]

...
The question is whether it's practically possible (and I might add, without drastic measures such as diverting entire world's lithium production into batteries production for decades, or making electricity permanently x20 more expensive, or something like that).

Looks like it is possible. Many battery types exist, we are not limited to expensive lightweight ones. Sodium-Ion, good old Lead-Acid, Sodium-sulfur, Ni-Cd, Al-ion. New types of batteries are being looked at.
...

An all solar US is *not* practically possible using only battery backup, for exactly the reason you suggest (at least). This limitation has been addressed earlier in the thread. There is not enough lead, not enough lithium produced in this world to build the hundreds of TWh required, nevermind replacing it every half dozen years or so. Basic assumptions and facts: 336 billion kWh of storage required with 15 kg of Pb per kWh is 5 billion tons of Pb. Global reserves of Pb are 80 *million* tons.

http://physics.ucsd.edu/do-the-math/2011/08/nation-sized-battery/

This calculation on storage is not really necessary, and the order of magnitude mismatch somewhat predictable, if one looks first at the enormous size of existing coal, gas, and oil production, just the volume and mass of hydrocarbon. Or, see the scope of world's existing hydroelectric dam capacity, though it supplies only a dozen percent or so the world's electric power.

 

[Salvador]

FFS , my long written and carefully edited last post to answer anorlundas assumption is deleted because the rulers of PF hate it :DOk well , nikkkom I don't understand your stance on ecology quite frankly , you seem to dislike nuclear power plants for being dangerous and some points you use for proof are actually rather slippery if not outright wrong , but when it comes to making thousands of tons of batteries for a energy storage system that atleast at current technology is simply no practical you then are ok with that.
To my mind batteries are some of the nastiest and toxic products in all of electronics , quite frankly a piece of an old turbine that has been in a nuke plant and has some small radioisotope residue on it is to my mind a million times cleaner than a trailer load of li-oh batteries.
All the energy used and toxic gasses produced at making them and then after a few years of intensive use one must recycle them , recycling probably being the hardest part , my friend works at a local recycling center near my town , even though it's small and they don't recycle the very basics they just prepare and split up the parts so that they can then be further refined at their destination and even then that smell in the air is one thing I will remember for a long time.

I think we are already deep under water in terms of how many small devices all rely on batteries , to think that we could also use them for massive mega amp energy storage I don't know seems crazy.Also as much as I know batteries like light loads under heavy constant loads they tend to fail faster and something go with a bang.

Flywheel in a vacuum could be an interesting thing but I assume it's energy density is just not big enough or the mechanical engineering and amount of metal would be over the top probably.

 

[Snerdguy]

There are two ways to look at it. Is it possible? Could it be done? Yes, I think it is technologically possible. But, certain things would have to happen. For one, Photo voltaic cells have to highly efficient, cheap enough and reliable which I think is doable. Secondly, we need to make some scientific breakthroughs with superconductors so that the energy can be distributed efficiently. That's because, to make a working system, it needs to be global so that there will solar energy available twenty-four hours a day.

The biggest problem is that, in order to provide energy just from photo voltaic cells, we would need global cooperation. All countries would need to work together so that everybody can tap into solar energy. That's not looking very likely for the foreseeable future. There's just too much inequality in the world right now. We have to over come that in order to use our resources wisely and if we ever want to have Star Trek sized achievements like interplanetary travel.

 

[Salvador]

You are correct about the "working together" which can help the civilization to achieve greater goals faster but as you know, not all people from the whole population are smart enough , capable enough or willing enough and some are plain idiots , some are criminals some are lazy , it's the choices we make that makes this world the way it is so let's look at this from the way it is.

Also as for the way it is science is the way it is and if I'm not mistaken which I hope you will kindly correct , superconductors require energy input to keep them superconducting because eventually heat will reach inside and destroy that state , not to mention the complexity of such technology , I have heard talks about superconductors uses for energy transmission but i think it's not practical atleast not now and I doubt also about the future.
HVDC line loss is already low enough even with our current switching substations , superconducting cables would really mean star trek level talking in this thread, not that I'm against it it's just that Stanley Kubrick will roll over in his grave , peace be with him he was a great director.

 

[OmCheeto]

I think the calculator let's you adjust tilt of the panels. it set mine at 20 degrees,

Me too.

I don't know whether that's off vertical or off horizontal...

Off horizontal.

and whether it's a simple default or some function of the local 35° latitude it used for local irradiance.
Might you try tilting for perpendicular to sun around winter solstice and see if winter output gets any better ?
Optimize for winter , accept a little less in summer when you don't need it ?

I'll probably experiment with tilts too, after some more cement work in the yard...

Good idea:

Om's system
4 kilowatt system
kWh generated per month
tilt ->_0°____20°___45°___90°
Jul___612___597___568___291
Dec___95___145___155___144​

Now everyone's situation is different, so my system won't work for you, and yours won't work for me.
But my idea was to have a mixed system.
Installing a vertical thermal collection system on the the south face of my house, I can generate 756 kWh for the month of December.
I checked the data for my energy use over the last year and have determined that my heating requirements are 700 kWh/month, for the winter months.

My lowest summer energy consumption over the last 25 years was last October, where I used 303 kWh for the month.
I checked my refrigerator, and it is rated at 790 watts. My guess is that it accounts for most of my summer electric bill.
Now, for a not small cost, I can pick up a refrigerator that uses 1/10th that amount. (Sunfrost RF19, $3500, 31 kWh/month)
So I'm thinking I could get away with only a 100 kWh/month solar voltaic system(1000 watts, $5000 professionally installed, $1000 if I do it), along with the 756 kWh solar thermal system (DIY construction and installation: $2000).

Now some people might claim that I've forgotten about the 7 day battery.
Not really.
I found a 2000 gallon swimming pool, for $59, that will fit in the crawl space of my house.
I've determined that if I heat it up to 190°F, it can store enough thermal energy to last me about 3 weeks.
So that far exceeds my thermal requirements.

Tesla's Powerwall stores 6.4 kWh, so that's only good for two days.
hmmmm...
I hear the Tesla Model 3 will have a 60 kWh battery. That would keep my food cold for 20 days.
And I'll probably have to hack into it to extract the energy.

U of Florida did research on thermal collectors forty-five years ago
and concluded a DIY'ers can't beat flat plate collector with intimate contact between plate and tubes.
They used copper sheet with copper pipes soldered to it on 12" centers
because the average home handyman can solder copper but he can't weld aluminum.
4 X 12 feet makes plenty of hot water for a family of four in Florida.
Does it ever freeze where you live?

[edit]
According to this website, 26 days a year.

Month___<=32°F___40°F
January_____8______24
February___6_______20
March______3______18
...
November__2______14
December__8______26
Year_______26_____118​

If not , consider replacing your water heater with a flat plate collector & elevated tank for thermosiphon .
View attachment 100130

Zero moving parts, zero maintenance.
Doesn't make kilowatts but displaces them with zero complexity. No electronics.
At a conservative 100kwh/month for two people(most water heater estimates are twice that see https://www.keysenergy.com/appliances.php )
and 15cents/kwh = $15/month
a thousand dollar homebuilt would pay back in 5.5 years vs ten for PV

this is not a hijack - a kwh saved is 3412 BTU's earned.
Save that beautiful electrical energy for more noble things than heating water - like posting on PF.

old jim

I have lots of bilge pumps. I ain't afraid of no movin' parts!

 

[jim hardy]

I have lots of bilge pumps. I ain't afraid of no movin' parts!

IN THAT CASE
you don't have to use thermosiphon, meaning your thermal collector panel can be mounted above the hot water storage tank.
Running a DC circulation pump from a pv panel built into the collector would save running conduit and housepower to it...
Just install a flapper valve to prevent nighttime thermosiphoning of hot water back up to the collector , for your BTU's will re-radiate back into outer space...
...unless you electroplate the whole collector with blackened nickel and that's another story...
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19770013623.pdf

old jim

 

[Snerdguy]

You are correct about the "working together" which can help the civilization to achieve greater goals faster but as you know, not all people from the whole population are smart enough , capable enough or willing enough and some are plain idiots , some are criminals some are lazy , it's the choices we make that makes this world the way it is so let's look at this from the way it is.

Also as for the way it is science is the way it is and if I'm not mistaken which I hope you will kindly correct , superconductors require energy input to keep them superconducting because eventually heat will reach inside and destroy that state , not to mention the complexity of such technology , I have heard talks about superconductors uses for energy transmission but i think it's not practical atleast not now and I doubt also about the future.
HVDC line loss is already low enough even with our current switching substations , superconducting cables would really mean star trek level talking in this thread, not that I'm against it it's just that Stanley Kubrick will roll over in his grave , peace be with him he was a great director.

After I tried to explain it in detail, I found an article that explains it better than I can...with photos even. http://www.extremetech.com/extreme/...es-the-way-for-billions-of-dollars-in-savings

 

[OmCheeto]

IN THAT CASE
you don't have to use thermosiphon, meaning your thermal collector panel can be mounted above the hot water storage tank.
Running a DC circulation pump from a pv panel built into the collector would save running conduit and housepower to it...
Just install a flapper valve to prevent nighttime thermosiphoning of hot water back up to the collector , for your BTU's will re-radiate back into outer space...
...unless you electroplate the whole collector with blackened nickel and that's another story...
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19770013623.pdf
View attachment 100219

old jim

Nickel plating! Perhaps you aren't aware of my budget for these types of experiments.

solar thermal collector hardware costs

$11.98 1/2 in. x 100 ft. Distribution Tubing for Drip Irrigation (thermal collection)
$9.99 1/2 in. thick, 4 ft x 8 ft aluminum backed styrofoam (insulation & reflection)
$70.00 2 x 2 ft x 8 ft x 1/4 inch polycarbonate thermal sheets (so everything doesn't freeze at night)
$10.00 wood frame (holds everything together without duct tape)
$0.00 5 x bilge pumps (5 boats, 5 bilge pumps)
$0.00 3 x 50 watt solar panels (dad bought them back around 1990, for probably $500/panel. He died in 2005. I got em)​

I balked at the $70 for the polycarbonate insulation, but knew it wouldn't work without it.
But then, when December rolled around, I knew this was one of the stupidest scientific investments I'd ever made...

View from my front porch in the middle of winter:

Those are all my neighbor's non-deciduous trees, so I really don't have much say in the matter...​

But it made my sister happy, and that's worth a lot.
And I think I can pawn off the panel to one of my friends, in exchange for boat rides.
She has a new houseboat, with a huge deck, and all of us, um, huge fans of summer, have been trying to talk her into installing a hot tub.

"It's going to cost a fortune to heat that thing!"
"Not with a "free!", OmCheeto solar water heater it isn't".

 

[Mark Harder]

Yes, putting all that capacity in one geographic area seems foolhardy. What if it were distributed, as some have suggested, on rooftops? How many homes would be required to serve our total need? If every home devoted 25 m² to solar cells, and 897,000 km² = 8.97*10¹² m²was required, that's over 35 Billion homes, no? Methinks we should be thinking of consuming less. That's our eventual fate anyway.

As for the problem of storage of excess power, could it be used to hydrolyze water, store the water for times of excess demand and use it as fuel for fuel cells or generators driven by internal combustion on site? Locating the plants in a remote desert is out of the question, but what if they were built near existing hydroelectric projects? A reservoir provides a ready supply of water and a natural container for waste water. But then I haven't estimated the quantity of water required...

 

[nikkkom]

Photo voltaic cells have to highly efficient, cheap enough and reliable which I think is doable.

It is not "doable". It is DONE. We have cheap 20% efficient solar panels.

 

[nikkkom]

An all solar US is *not* practically possible using only battery backup, for exactly the reason you suggest (at least). This limitation has been addressed earlier in the thread. There is not enough lead, not enough lithium produced in this world to build the hundreds of TWh required, nevermind replacing it every half dozen years or so. Basic assumptions and facts: 336 billion kWh of storage required with 15 kg of Pb per kWh is 5 billion tons of Pb. Global reserves of Pb are 80 *million* tons.

Why would you use Pb batteries for this? Nickel-iron ones, for example, are cheaper, and they last 30-50 years. They are heavier, yes, but for stationary batteries it is not critical.

 

[nikkkom]

To my mind batteries are some of the nastiest and toxic products in all of electronics , quite frankly a piece of an old turbine that has been in a nuke plant and has some small radioisotope residue on it is to my mind a million times cleaner than a trailer load of li-oh batteries.

I don't know what "oh" is, but Li is not a right material to build stationary large-capacity batteries. Too expensive.

 

[nikkkom]

In an Hour for 1sq.mt solar panel will generate around 200W,
so for 5 hours/day will generate 1000W or 1KW/day,

Your units are off. Watts are power, not energy. W is Joule/second, so KW/day is nonsense.

1 sq.m. of 20% efficient solar panel generates some 30 Watts daily average in a sunny, southern US state.

for 10m wide road, it will generate 10KW/day,
for 1KM long road, it will generate 1000*10 = 10,000KW/day or 10MW/day,

1km x 10m road is 10000 m^2, so you may hope to generate 300kW daily average from it. You'd need 3333 km of such roads to generate one gigawatt of power (roughly equal to one todays powerplant).

 

[Salvador]

whoever here said about the superconducting lines I think we are still far away from them because that article that was given doesn't tell the story about how much energy will be lost maintaining the liquid nitrogen running through the cable.
So for a nationwide grid one must then count the losses and the extra complexity and materials for a current superconducting technology VS HVDC for example, surely a tough task to calculate here so I will just leave it at that.

 

[jim hardy]

it'll generate around 3050 MW per KM per Year

I know nothing about electric rates or costs of capital and labor in India.
In US, to wholesale that power at even $50 a megawatt-hour
https://www.eia.gov/electricity/monthly/update/wholesale_markets.cfm

3050 mwh/yr is $152,500 a year.
Can you finance, build and maintain it for that ?
I think instead your politicians will do what politicians in Florida and Colorado did -
install license plate cameras and have the computers send everybody who drives past one a bill for about ten bucks.

 

[jim hardy]

I did my calculation as per google search for solar power output per day,

i think the complaint is that you(and the author of that solar roadway article) confused power (kw) with energy(kwh)

that wipes out credibility even if the arithmetic is right , because the physics is wrong.

Sadly journalists do not have to know a thing about science and shouldn't write about it if they don't.
That author and his editor did their publication a disservice, their inattention to that detail got them dismissed as enviro-babblers.

I checked your and Nikkom's numbers . You only disagree by your 1000 vs nikkom's 720 watt-hours per square meter per day.

old jim

 

[nikkkom]

I did my calculation as per google search for solar power output per day, below are some of the links, kindly check,

http://www.theecoexperts.co.uk/how-much-electricity-can-i-generate-solar-panels
"The standard solar panel has an input rate of around 1000 Watts per square meter, however on the solar panels available at present you will only gain roughly 15-20% efficiency at best. Therefore if your solar panel was 1 square meter in size, then it would likely only produce around 150-200W in good sunlight."
For example: 2 square meter panel x 1000 = 2000 x 0.20 (20% efficiency panel) = 400. 400 x 5 hours of sun hours = 2000 Watt hours per day.

https://livingonsolarpower.wordpress.com/2013/03/23/basic-solar-energy-math/
Under clear skies and good sunshine each square meter is receiving about 1000 watts of solar energy. At typical 15% panel efficiency, a 1 sq m area will generate 150 watts of power.

Which is roughly equal to what I said. ~30W of power from 1 m^2, when you average it over 24 hours.

 

[nikkkom]

yes there maybe plenty of land available but i try to reuse the existing land more efficiently,

Whereas what should be done is to use *money* more efficiently. You need to economize a resource only if it is scarce. In Japan, land is a scarce resource. Not in US.

transmission losses will also be less as compared to installing solar panels in remote areas & bringing that power to city

Calculate the savings. You may find out that they are unimportant.

maintenance cost for roads will also reduced

I seriously doubt that.

 

[Baluncore]

+ maintenance cost for roads will also reduced, as now there will be 24x7 shade over roads.

That will be a problem. The sunshine on the black bitumen heals the cracks that form. If it is always in shade you will need to change the composition of the road material to a softer material blend.
Take a look in a car park where there are wide white arrows painted on the road surface. Do you notice cracks formed in the surface where the white paint keeps it cool, but no cracks where it is black because it can heat, flow and so heal?

erashish14, are you the author of those web sites ?

 

[Salvador]

erashish14, are you the author of those web sites ?

That's Baluncore being funny :DOverall why don't we forget about the solar panel roads , they are even if possible not practical due to the simple fact that a road is under heavy stress from traffic and needs to be built on materials that last.The maintenance just would not be worth it.
Although maybe this idea could be used in cities in large car parks for example or in other areas were the speeds is low and stresses are low.
Just think about the load a typical highway sees you really think it would be practical to have some fragile solar panel semiconductor or whatnot material lying beneath the surface and the surface then would have to be anything other than bitumen or concrete because those two would kill all the sunlight coming through.

 

[jim hardy]

The utility electricity sector in India had an installed capacity of 298 GW as of 31 March 2016.[1][2] Renewable Power plants constituted 28% of total installed capacity and Non-Renewable Power Plants constituted the remaining 72%.

https://en.wikipedia.org/wiki/Electricity_sector_in_India

At 300 kilowatts per KM
to get 10% of total capacity by covering roads
you'd need to cover 298E9 / 300E3 = 993,333 km

. As of 2011, 54 percent – about 2.53 million kilometres – of Indian roads were paved.[2][3]

https://en.wikipedia.org/wiki/Indian_road_network
so you have enough roads for 10 or 20 percent. 993,333 km out of 2.53 million km = 39% .

 

[OmCheeto]

3050 MW per KM per Year

I think they must have their dimensions confused. That idea is a joke.
That amount of advertising space will depreciate the value of all advertising space.

I think that's supposed to be 3050 MWh per km per year.
I calculated it for my neighborhood and came up with 1027 MWh per km per year. (I measured the width of my roadway in front of my house yesterday at 20 feet)

But like solar surface roadways, I don't consider elevated solar roadway covers economically feasible.
Around here, they'd need to be designed to withstand sustained winds of 60 mph, and gusts of 120 mph.

...at Portland, Oregon's major metropolitan area, measured wind gusts reached 116 miles per hour (187 km/h) [ref]
​

And that person really needs an editor.

On the same Road, we can collect around 9,75,360[sic] Liters of Rain Water per KM, with 100mm of Rainfall (Average Rainfall in INDIA) & if we consider 700 Liters of Water for an Average Family...​

I'm pretty sure that's supposed to be 975,360 liters, as that yields a roadway width of 9.75 m (or 32 feet, for us yanks.)

 

[mheslep]

Why would you use Pb batteries for this? Nickel-iron ones, for example, are cheaper, and they last 30-50 years. They are heavier, yes, but for stationary batteries it is not critical.

Me? Pb acid is the most common rechargeable battery in the world today by kWh produced and for good reason. It's cheap and tough. The long life you cite for nickle iron is for stand by or shelf life, not the daily cycles required to back up solar. At that rate of use, any solid battery has at most a dozen years of life.

 

[nikkkom]

Me? Pb acid is the most common rechargeable battery in the world today by kWh produced and for good reason. It's cheap and tough.

And about two times lighter than Ni-Fe, for the same capacity. That's important in a car, and I guess one of the reasons why Pb batteries, not Ni-Fe, are used in cars.

For stationary applications, weight is not critical.

 

[mheslep]

And about two times lighter than Ni-Fe, for the same capacity. That's important in a car, and I guess one of the reasons why Pb batteries, not Ni-Fe, are used in cars.

For stationary applications, weight is not critical.

Right, solar backup need not be mobile, but mass matters for shipping and (frequent) replacement, especially when the mass is on the order a couple of mountains. There is no practical route at present to battery back up of a single large (GW) power plant for a week, nevermind an all solar US, not with batteries of kind.

 

[Baluncore]

"erashish14, are you the author of those web sites ?"

That's Baluncore being funny :D

No Salvador, it is a serious question. Both erashish14 and the site made many of the same mistakes.
I still wait for an answer from erashish14.

[edit] Now all erashish14's posts have disappeared from this thread. I guess that answers my question.