Parking lot sunshades

[AutobahnSHO]

That's interesting about the % of power that would "disrupt" the grid.
I guess you could always store the sun power into batteries and have it discharge at a steady (smaller) rate into the national grid..

Gocougs is right about solar vs. fossil fuels-
Fossil fuels (coming from the SUN,) took thousands (millions?) of years to be produced. There's no way you can match that with solar cells.

EVENTUALLY the fossil fuels will run out, we'll be doing something like soylent green, riding on stationary bikes in our house with power generators on to power our lights and TVs...
(Unless the US finally figures out how to pitch nukyular powr to the public.....)

[S204STi]

I think that if you can make this little sub-panels cheap and modular so that you can easily repair them, and/or surface them with plexiglass or something similarly durable against impact per Middle Path's concern, and these could work.  A parking lot could then potentially make money off the electricity as well as the tenants; or alternatively offer free parking and let the solar panels pay for the whole thing over time.  That said, some improvements to the technology need to occur first, on many fronts.

[Galaxy]

Gocougs is right about solar vs. fossil fuels-
Fossil fuels (coming from the SUN,) took thousands (millions?) of years to be produced. There's no way you can match that with solar cells.

Very little of the energy got trapped in carbon fuels.

[Galaxy]

Given that solar and wind plants only are producing power 20-25% of the time, it should be rather obvious you can't count on them producing more the ~25% of the power grids power.

Two things:

It  is statistically close to impossible that solar power plants in Texas are going to be down at the same time as wind turbines in Kansas and tidal power plants in California. With 1 million volt transmission lines the line loss over long distances becomes a minor problem.

The amount of solar power available does not equal 100% it is in excess of 10,000%.  You only need a few percentage points to make enough electricity. In the few hours that solar systems  work they "gather" enough electricity to cover the time that they are off line. As I mentioned earlier liquified salt can be used to store the heat gathered from the sun to feed steam turbines at night. Plus in Africa Desertec can coount on having over 10 hours a day of generation capacity.

[Tave]

I've heard some EEs say that a switch to solar would require a paradigm shift in utility structuring. We'll be seeing more diffuse, decentralized systems and fewer common providers.

[Galaxy]

PJM is not a company, they are the regulators of the largest power grid in the world at roughly 150,000 gigawatts of generation and able to send out or pull in another 100,000 gigawatts from neighboring grids... it puts europes grid to shame. 

Actually it does not. If Wikipedia can be trusted PJM Interconnection delievered 700 TWh in 2008. In 2007 the European connected Network delievered 2607 TWh and in 2007 the Scandinavian countries where not yet conneccted.

[r0tor]

Actually it does not. If Wikipedia can be trusted PJM Interconnection delievered 700 TWh in 2008. In 2007 the European connected Network delievered 2607 TWh and in 2007 the Scandinavian countries where not yet conneccted.

all of europe is not under 1 regulator

To my knowledge, they hold the current world record of controlling 144,644 MW's in the summer of 2005

[r0tor]

also, if you want my honest opinion - the african desert project is more about getting people to invest about $500billion in a needy part of the world then anything.  Its technology is still not reliable after a good 40 years of development, the sheer mass of the thing means it won't be built for 30 more years, and doing the math you have 10 hours on average in a 24 hour period and then subtract out the effects from weather, dust storms, and dirt clouding up the lenses and your back to the same 25% operating capacity factor that is observed by any real current solar generating station.

[Galaxy]

all of europe is not under 1 regulator

Technically that is correct. Eventually we will get rid of the national regulators since each EU member having it?s own regulator is silly. My point was that (to my knowledge) the pan european grid with it?s ~400 million users is the largest interconnected grid. It would not surprise me in the least if the Chinese have something bigger. If they don?t now they certainly will soon.

[SVT666]

It wouldn't work in a snowbelt.

[GoCougs]

Prices for solar panels are coming down rapidly.

Nuclear power would be unaffordable if the government did not underwrite the insurance. No one would take the risk.

But segregated solar is DOA without energy storage (batteries).

Nor would hydro if the government hadn't built the dams. (The point being the relatively low energy density of solar is its proverbial and perpetual Achilles heal.)

[Galaxy]

also, if you want my honest opinion - the african desert project is more about getting people to invest about $500billion in a needy part of the world then anything.  Its technology is still not reliable after a good 40 years of development, the sheer mass of the thing means it won't be built for 30 more years, and doing the math you have 10 hours on average in a 24 hour period and then subtract out the effects from weather, dust storms, and dirt clouding up the lenses and your back to the same 25% operating capacity factor that is observed by any real current solar generating station.

Being honest I see the biggest problem with Desertec being the somewhat iffy security situation in North Africa. I hate to say it but the best place may be Gaddafi?s little empire instead of the democracies like Egypt.

I think Africa can profit from this project, although there are already critical voices in Europe saying that with this project we are raping developing countries in the same way we do with oil and that in the end the average Touareg will not see a penny from this. They may be right.

In any case companies like Siemens, ABB, E ON, and Schott Solar are not charities. They obviously think this is a cash cow. Of course I do expect them to put their money where their mouth is. While some subsidies will be unavoidable they are going to have to invest $$$ $$$ $$$ $$$.

[GoCougs]

On average the total solar energy absorbed by the earth?s surface is 3,850,000 exajoules per year. That is almost twich as much as the estimated energy that can be harvested from coal, oil, natrual gas and uranium. Even if the estimates are off by 100, 200, 300% it does not matter.

The total energy expenditure of every insect on the planet is also immense, but we'd never use them to power our homes. (Meaning, energy density is the inherent barrier, not energy availability.)

Currently modern solar panels can convert around 150-200W per square meter, from solar energy measuring 1000W. That might not be very efficient but it means that most houses have a roof surface big enough to sustain them. While the systems do pay pay off within a few years the upfront costs that need to be payed at once are of course a problem.

On the best of sunny days; but what of moderate climates, or those subject to extreme periods of darkness, or just a hailstorm?

At best, and I'm being generous, it makes sense in the sunniest and calmest (i.e., no weather) of locations - such as the SW US, and only on a large scale.

[Morris Minor]

I took a quick look web site of the company that makes the solar panel parking lot sunshades.
http://envisionsolar.com/project-portfolio/

It looked to me like a good chunk of  their installations are showcases or are at public institutions. It would be better if this type of thing became a viable proposition in the for-profit world (grocery stores, office buidings, shopping malls etc).

The most logical use would be to use them to offset the power consumption of a building's cooling systems., which run the hardest in sunny weather.

[Tave]

On the best of sunny days; but what of moderate climates, or those subject to extreme periods of darkness, or just a hailstorm?

At best, and I'm being generous, it makes sense in the sunniest and calmest (i.e., no weather) of locations - such as the SW US, and only on a large scale.

The newer stuff is performing better and better in low-light environments.

[Raza]

The newer stuff is performing better and better in low-light environments.

False.  Solar power is not now, has not been before, and will never be viable.  Scientists are not even sure that the sun exists. 

[Onslaught]

False.  Solar power is not now, has not been before, and will never be viable.  Scientists are not even sure that the sun exists. 

Yes, when they try and look at it they go blind. So they have no way of being sure.

[Galaxy]

The total energy expenditure of every insect on the planet is also immense, but we'd never use them to power our homes. (Meaning, energy density is the inherent barrier, not energy availability.)

On the best of sunny days; but what of moderate climates, or those subject to extreme periods of darkness, or just a hailstorm?

At best, and I'm being generous, it makes sense in the sunniest and calmest (i.e., no weather) of locations - such as the SW US, and only on a large scale.

The average solar radiation, taking into account the angle at which the rays hit the earth and the fact that at any given time half the planet is in darkness is ~340W per sqaure meter. That does not take into account weather.

I would like to direct your attention towards the Waldpolenz Solar Park in Germany. They use thin film panels that cover 110 hectares which generate ~40,000MWh per year. Keep in mind that Germany is not exactly an ideal place for solar energy with the rain, the fog, and the clouds.


Here is a map from the Desertec project. Note the surface area of the Sahara that they claim can power the earth. It might be optimistic but it does show the potential.

[r0tor]

I would like to direct your attention towards the Waldpolenz Solar Park in Germany. They use thin film panels that cover 110 hectares which generate ~40,000MWh per year. Keep in mind that Germany is not exactly an ideal place for solar energy with the rain, the fog, and the clouds.

the plant i work at runs only 20% of the time due to costs, takes up <10 acres of land (<4 hectacres), and generates ~1,500,000MWh per year..... and i don't even work at a "big" plant at ~1,000MW ouptut

For more perspective, the Waldpolenz station is 40MW.  40,000 MWh a year is the equivalent of it running at full output 1,000 hours a year out of a possible 8,760hrs a year which is about 11% of the time  ....

[Galaxy]

the plant i work at runs only 20% of the time due to costs, takes up <10 acres of land (<4 hectacres), and generates ~1,500,000MWh per year..... and i don't even work at a "big" plant at ~1,000MW ouptut

For more perspective, the Waldpolenz station is 40MW.  40,000 MWh a year is the equivalent of it running at full output 1,000 hours a year out of a possible 8,760hrs a year which is about 11% of the time  ....

Like I said keep in Mind the German weather. The sun surrenders to the clouds in November and only regains the upper hand in March, usually to suffer a fallback in April before summer starts in May. No wonder we have a reputation for being cold and unfriendly...

Under those circumstances I think the performance is Ok. The same plant in Africa would obviously blow it away. I do think that such large scale plants should mostly be built in more sunny places. I guess the companies want to have a few here as a kind of business card.

Decentralized solar power- home owners putting  a few square meters on the roof- is something that can be done in Germany and other less sun privliged places. Add it all up and you end up with one impressive superplant. However sun power from the Desert is where the future us at.

[3.0L V6]

I could see small scale solar setups on home roofs and whatnot in the southwest United States (Phoenix, LA) to function as a 'base load' aid - ie: power all the home electronics on standby, assist with A/C, but at a large scale, there's too many downsides to really make it cost effective.

[GoCougs]

The average solar radiation, taking into account the angle at which the rays hit the earth and the fact that at any given time half the planet is in darkness is ~340W per sqaure meter. That does not take into account weather.

I would like to direct your attention towards the Waldpolenz Solar Park in Germany. They use thin film panels that cover 110 hectares which generate ~40,000MWh per year. Keep in mind that Germany is not exactly an ideal place for solar energy with the rain, the fog, and the clouds.


Here is a map from the Desertec project. Note the surface area of the Sahara that they claim can power the earth. It might be optimistic but it does show the potential.

[snip pic]

My assertion is that it doesn't work it's that without the government pulling significant strings it'll never come into being on a grand scale. In other words, it is a viable replacement but not a viable substitute.

Solar is destined to go the way of wind power and ethanol; when the government bails on it (as it has in the US, especially ethanol), the market will bail on it as well.

[ChrisV]

I know what you meant, but you're just flat out wrong. The ROI on new solar panels is much shorter than 20 years.

Life-cycle energy balance studies for solar panels suggest an energy payback period ranging between 0.7 and 1.3 years on the low end (for super-efficient FLATCON panels incorporating fresnel lenses to focus the sunlight) to between 4 and 15.5 years for Si-Sc modules. mc-Si panels are worst at 25 years payback if one considers carbon emissions, but they're not representative of the total. Most types of solar panel can be energetically paid off in a couple years - maybe 10-20% of their total service lifetime.


I like having BP solar just a few miles away. I'm also looking into putting some panels on my house to help offset the cost of electricity running the AC in the summer. We've got houses here in MD that actually sell power back to the power company for much of the year.

[GoCougs]

I could see small scale solar setups on home roofs and whatnot in the southwest United States (Phoenix, LA) to function as a 'base load' aid - ie: power all the home electronics on standby, assist with A/C, but at a large scale, there's too many downsides to really make it cost effective.

But now you have purchase, maintenance and replacement costs of two disparate systems (i.e., you lose out on economies of scale).

[ChrisV]

http://www.oregon.gov/ODOT/HWY/OIPP/docs/solar_panel_lifecycle.pdf

[ChrisV]

figuring 8% panel efficiency. Now split those areas up into much smaller localized installations..

Hehehe....We should stop paying midwest farmers to harvest crops we can't use, and pay them to harvest sunlight that we can use...

Now, it'll never happen due to politics and the reality of production. Plus having numerous different sources of energy is good so that you don't put all your eggs in one basket, but it does point out how feasable it could be.

[Morris Minor]

What will you do when the Africans hold the power plants to ransom? It really is better no to rely on Third World countries for anything important. We've learned that the hard way with getting oil out of the Middle East. Do you really want North African Islamists having control of your electricity supply?

[ChrisV]

What will you do when the Africans hold the power plants to ransom? It really is better no to rely on Third World countries for anything important. We've learned that the hard way with getting oil out of the Middle East. Do you really want North African Islamists having control of your electricity supply?

They'd have control of their OWN electric supply, not ours.

Think about this solution...

We pay midwest farmers subsidies to NOT grow crops on their land, or grow crops we don't need. What if we paid them subsidies to have solar farms to generate something we CAN use? The 1000 square miles that is projected to provide us with enough power is a 10x100 mile area. That could be spread out over a lot of farm acreage that is currently being paid to NOT grow crops...

And if you add in local generation for businesses and townships around the country, that midwest or southwest basin surface area could be reduced even further. Compare that dot with the breadbasket area of the US. It's really not that big, especially broken up into manageable chunks and spread out over thousands of rooftops and , say, parking lots...

Now add this info:

http://digitaljournal.com/article/160431

Researchers in New Zealand develop natural dye sensitized Solar cells that generates more energy from the Sun and costs one tenth of Silicon Solar cells.

The solar cells are made with Titanium dioxide rather than expensive silicon cells, and these solar cells are dyed with synthetic dyes made from simple organic compound. One green dye is the syntheticchlorophyll derived from the light harvesting pigment plants use for photosynthesis. So these Green colored solar cells mimic nature and harness the sun energy and cost one tenth of existing silicon based solar cells.

The Green Solar cells also generate more energy under low light conditions, a 10 x 10 cm green solar cell can generate enough electricity to run a small fan under low light and thus can be used even under cloudy conditions. These dyes can be incorporated into the windows, trap the sun energy and can then be used to generate electricity. These green solar cells are environmentally friendly since they are based on titanium dioxide which are renewable and non-toxic

These are basically Gratzel cells.

In Gratzel cells particles of TiO2, coated with a dye that absorbs at a wide range of wavelengths given off by sunlight, are placed between two electrodes in an electrolyte solution containing iodine ions. The cells generate electricity when the energy captured by the dye makes the electrons in the dye molecules jump from one orbital to another. The electrons then jump onto the TiO2 particles and diffuse towards one electrode, while the iodine ions carry electrons from the other electron to regenerate the dye.

[ChrisV]

Also, what if we could replace the tops of sidewalks with these (and base them off of the aforementioned Gratzel cells instead of silicon, so they work better in low light, cost less, and make more power than silicon):



http://www.popsci.com/scitech/article/2009-08/solar-panels-built-roads-could-be-future-energy

Instead of roads, though...

[GoCougs]

What will you do when the Africans hold the power plants to ransom? It really is better no to rely on Third World countries for anything important. We've learned that the hard way with getting oil out of the Middle East. Do you really want North African Islamists having control of your electricity supply?

Precisely - it smacks of the very worst of statism.

We do not want governments on any level; world, region, national or state; to be in charge of energy production and distribution.