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What if.. solar cells

What if.. solar cells

What if.. solar cells

(OP)
Currently solar cells cost around $4 per peak watt. 1 peak watt of cell gives you around 7 Wh per day of electricity on a good day, or 4 Wh if it is poor weather.

There are several technologies coming up in the next five years that could see solar cells dropping to around $1 per watt. In fact even now the price is driven by high unsatisfied demand rather than production costs. My house uses 1500*24 Wh per day, so I'd need 9000 peak W of cells, which is almost viable at first sight, given that my current bill is around $800 pa.

So, how would your field be affected by cheaper solar power?

Can YOU think of a good diurnal storage technology that we haven't seen yet?

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: What if.. solar cells

I just visited a neighbor's farm to view his wind turbine.  Enough to power his fram on most days (20 head dairy--not big, he's semi-retired).  The visit was part of a state-wide tour of alrenative energy.

It's amazing how much poltical resistance wind turbines are getting.  Neighbors don't want to see them.  "Spoils the view."  What a load of bull!  Farms don't exist for the sake of generating bucolic views, they are working enterprises.

RE: What if.. solar cells

We're already seeing solar powered instruments for remote locations, metering stations etc. I could see a compressor station where all the instruments and auxilary power was solar...

Seems to me that with the right cell efficiency that a solar powered car would be possible.

Really, wind power is just a form of solar as well... Wind has become pretty big in west Texas (where there are few people to complain about the view being spoiled.)

-The future's so bright I gotta wear shades!

RE: What if.. solar cells

(OP)
No, a solar powered car is never going to be practical, been there, done that, got the T shirt, won the world championship.

In order to get acceptable performance you have to optimise everything, including weight. This leaves you in a large expensive fragile slow single seater.

Much better to put the cells on your roof, and then charge the battery for your electric car up.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: What if.. solar cells

Wind turbines are probably the most effective use of solar power devised of so far. The comments about spoiling the view and killing a few birds will be a continuing argument. The real problem with wind generation is where it will take place which is mostly in the Great Plains where the wind is constant and land is easily available and cheap. The problem is transmission of the power to the places that need it. Line losses limits transmission distances. Power hungry industries may even relocate to areas of wind power and may even build their own generation capacity selling excess power onto the grid.

RE: What if.. solar cells

Solar panels are already very common in my industry - usually remote sites. They are, for the most part reliable. Their weakness is the total power available per square foot vs other solutions (eg TEGs). If there is low power consumption, they work well. If you need lots, then other alternatives may work better.

"Do not worry about your problems with mathematics, I assure you mine are far greater."   
Albert Einstein
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?

RE: What if.. solar cells

Next year Portugal is going to build the biggest Solar panel power station in the world. It will be located in Alentejo next to Spanish border.      

RE: What if.. solar cells

Wind farms in India exist as a cluster and are located only at favourable sites for the winds to give about 20 hours generation. The power generated is fed to the grid and the owner of the wind mill is allowed to draw the power or sell it to anyone.

As far as spoiling the beauty is concerned,its a treat to watch all the wind mills running. Next time I pass the area, I shall remember to take a few pictures and post it here.

RE: What if.. solar cells



"Solar cells and advanced fuel cells that can deliver up to 500 kW must be developed to power the craft. An aerodynamic design and a control system must be developed to help keep the airship steady amid the high winds at that altitude, without consuming excessive power. Another important factor is determining how the airship would react to changing temperatures as the sun rises and sets every day, heating and cooling the helium. Then there's the major challenge of finding materials for the airship's skin that are capable of withstanding the extreme ultraviolet radiation at such high altitudes for extended periods without becoming brittle."




To know more about this go to

http://www.defenseindustrydaily.com/2006/01/lockheed-wins-1492m-contract-for-high-altitude-airship-updated/index.php    

RE: What if.. solar cells

What we will need to make alt energy usefull is a
MEGA GRID
A massive HVDC power bus through linking the midwest to
the east as far as OHIO.

The purpose of this bus is twofold. First to average out
the availability of power because of weather patterns.
The wind is allways blowing somewhere right??
Also to deliver surplus to the hungry coastal areas.

Spurs off this MEGA GRID to the north and south with insure
it covers a very large geographic surface area to aid with
the weather averaging.

It will be extremely costly to build. Maybe even cost as
much as the Iraq war, but it should begin planning now.

There is no viable storage technology at present except
pumped resevoir water power that can even come close to
doing this averaging of power production for us. Hence the
need to spread out and connect the generation.

The capacity of the main trunk line would have to be
50 Giga Watts.  Something like two cables 3 feet thick at
1 mega volt.  It will be an engineering feat to rival any
before. But it is necessary

RE: What if.. solar cells

Make them look like the wind mill in Netherland.  Dont they look good?  :)

RE: What if.. solar cells

Wind "farms" are an obvious solution: the crops underneath, and the guy driving the tractor and combine harvester, neither of them need any space beyond about 20' above grade, and farmers can always use a few extra bucks by producing yet another "crop" off their land.  So combining wind farms with crop farms is a sensible idea.  Anybody who complains about the view being spoiled should be taken on a tour of some coal-fired electrical generating plants sometime.  Big stacks and piles of coal aren't all that pretty either.

RE: What if.. solar cells

Currnet solar cell prices are being driven not only by the high demand, but by a shortage of the raw polysilicon which may continue to 2010 or 2011.

RE: What if.. solar cells

Comcokid,

What you say is true, although I have heard that we could start to see significant increases is silicon production by the end of '08.

But this only affects the single and poly crystal silicon solar cells, not thin film cells.  In fact, the high price of silicon is really driving investment in thin film PV at the moment.  Your guess is as good as mine as to whether that investment stays after silicon prices come down.  But CIGS, in particular, have been getting a ton of investment in the last year.  Look at Nanosolar in Palo Alto, they just built a 100 million dollar factory to produce CIGS cells.

RE: What if.. solar cells

BrunoPuntzJones - I posted the reply just after reading a article in EE Times, Oct 30, 2006 p12, "PolySi shortage could impact wafer costs".

The article states: "The tight polysilicon market could last two years longer than previously expected, possibly continuing to 2010 or 2011".

The article is available at www.eetimes.com, but you have to setup a login ID to view it.

RE: What if.. solar cells

Comcokid,

Thanks for the update.  Any mention of the reason for the additional delay?  

Anyways, that's good news for thin film PV.

RE: What if.. solar cells

BrunoPuntzJones - The article indicates:

A) IC grade wafers supplies are sufficient, but solar grade polysilicon has been in short supply for two years already, and demand is skyrocketing.

B) Projections had been that shortages would end in 2009 when polysilicon vendors such as Hemlock, MEMC, Mitsubishi Materilas, REC and Wacker added additional capacity, but the increasing demand is outstripping original projections.

C) Solar cell and module makers are having trouble keeping up with US demand.

OEMs are working at better power efficiencies while reducing panel costs. Some companies are developing thin-film arrays which use less polysilicon but are less efficient.

The article mentions Solarbuzz LLC, which I found at the website: www.solarbuzz.com

RE: What if.. solar cells

Solarbuzz is sort of an industry portal / marketing frim or something like that.  

It's true that the current thin film cells aren't as efficient as the older silicon technologies but they also have a lot of advantages, one being material costs.  And there are a lot of good ideas in the works for higher efficiency thin film cells.  So I don't see the efficiency of silicon cells defeating thin film cells.

It will come down to production costs, and, frankly,  the industry has been doing an abysmal job when it comes to the production side of things.  I have seen some signs of change, but I'm not convinced yet.  

RE: What if.. solar cells

If it comes down to $/Watt, efficiency (i.e. area) isn't an issue when there is so much desert area on this World.  Take a look at Lomborg's view on solar power. (I don't claim to agree with his conclusions, but the maths look interesting)

RE: What if.. solar cells

(OP)
My house has say 60 m^2 of roof space. So if these new cheap cells manage a lousy 10% efficiency, and one sun is about 1500W, that is a 9000W nominal panel.

Which oddly enough if you refer to my first post, is just what I need.

That and a load of batteries (or whatever).

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: What if.. solar cells

Greg:  if the cells double as roofing, and stay waterproof at least as long as 25 year shingles, you may have something.  Trouble is, most of those cells won't be pointed toward the sun unless your house has a very wonky roof.  And if they wear out before they pay back, it's a poor investment.  But if you tax fossil fuels to attribute their REAL costs of consumption to those who consume them, payback will be a lot faster.

I see the real problem with current solar cell technology to be their embodied energy.  Are they finally generating ten times the energy in their lifetime that they take to make, transport to site and install?  Then you can call solar a "green" technology- and not before.  Windmills, on the other hand, don't suffer from this problem- because they deal with a concentrated form of the solar energy rather than depending on the solar flux directly.

Saw some articles recently about people trying to mimic biological photosynthesis as a means to generate/store solar energy, ie. using chemical photosensitizers.  What they neglect to mention is sensitizer degradation.  Unlike a tree, any device we build won't be able to make its own sensitizer to replace the amount that the sun de-activates, bleaches or otherwise destroys.  The sun is tough on chromophores long-term.  If the sensitizer costs more to replace than the energy you produce is worth, you don't have a process.  Evolution has come up with a pretty good system- mind you, it had a couple hundred million years to do it.

RE: What if.. solar cells

Maybe offshore Wind farms would be better.

http://en.wikipedia.org/wiki/Image:DanishWindTurbines.jpg

The neighbours won't be bothered by noise pollution.
Birds are far less likely to fly into the blades ... except for Seagulls and Cormorants ... and that would be a good thing anyway.
Doesn't take away from useable property and gets away from the NIMBY element.

Maybe they could also double up with wave power.

cheers

RE: What if.. solar cells

Maybe oil companies could improve their green image by siting wind turbines on their offshore rigs?

RE: What if.. solar cells

Oil companies have to have a "green image" before they they can improve it!!!

cheers

RE: What if.. solar cells

GregLocock

I found this stuff that could be useful for you to solar energize your house

“A "typical home" in America can use either electricity or gas to provide heat -- heat for the house, the hot water, the clothes dryer and the stove/oven. If you were to power a house with solar electricity, you would certainly use gas appliances because solar electricity is so expensive. This means that what you would be powering with solar electricity are things like the refrigerator, the lights, the computer, the TV, stereo equipment, motors in things like furnace fans and the washer, etc. Let's say that all of those things average out to 600 watts on average. Over the course of 24 hours, you need 600 watts * 24 hours = 14,400 watt-hours per day.
From our calculations and assumptions above, we know that a solar panel can generate 70 milliwatts per square inch * 5 hours = 350 milliwatt hours per day. Therefore you need about 41,000 square inches of solar panel for the house. That's a solar panel that measures about 285 square feet (about 26 square meters). That would cost around $16,000 right now. Then, because the sun only shines part of the time, you would need to purchase a battery bank, an inverter, etc., and that often doubles the cost of the installation.
If you want to have a small room air conditioner in your bedroom, double everything.”

About your statement “solar powered car is never going to be practical” definitely you don’t like to be outrun by a snail.




RE: What if.. solar cells

Somptingguy,

That is already being done. Shell for instance has a large wind energy business and is siteing windfarms on off shore locations, including old platforms.

-The future's so bright I gotta wear shades!

RE: What if.. solar cells

Corblimey,

Don't count on off shore stopping Nimbys.  Just ask Teddy Kennedy about the one planned off the north east coast of the US.

RE: What if.. solar cells

For the past few year Shell has been active in the Alternate energy resources arena. They have been conducting a few school programs too.

RE: What if.. solar cells

I have wondered what the environmental consequences of harvesting the wind are. What climate effects would there be is we took 75% of the energy out of winds that come on-shore? Will there be "wind rights" issues like there are "water rights" issues?

RE: What if.. solar cells

I think I've posted this before, I think SMS asked a similar question.  

My initial thought would be that a few thousand wind turbines wouldn't take any more energy out of the wind than the millions of trees that used to cover much of the worlds land area.

That's not to say it shouldn't be investigated but while one turbine probably takes more energy than 1 tree I doubt there'll ever be as many turbines as there were trees.

Plus I live out in the Mojave Desert and have stood down wind from vast swathes of turbines in the Mojave/Tehachapie area and believe me if they've taken 75% of the energy out then Bakersfield on the far side of the turbines would have been flattened by hurricane force winds.

RE: What if.. solar cells

(OP)
Well, to get back on my hobbyhorse, burning ANY hydrocarbon in a stationary installation is daft. Hydrocarbons are uniquely portable sources of energy, we should be preserving them for use in transport etc, not burning them to heat water up at home. Gas, in cars, works really well. It is a high octane fuel, and burns very nicely. In aircraft it would not be quite as good, for a whole bunch of reasons.

Having said that, I am a hypocrite on this. My house is ALL electric, and my hot water is warmed by off-peak electricity. Ultimately (in Australia) that means my hot water is coal-fired, inefficiently. That is, the coal is burnt in a very high efficiency boiler, turned into electricity fairly efficiently, transmitted to me, somewhat efficiently, and then used to heat water fairly efficiently. I have a strong suspiscion that this is inefficient compared with a domestic coal fired boiler. But at current prices, why wouldn't I do it this way?

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: What if.. solar cells

Greg,

The answer in the US to your question, "Why burn any hydrocarbon in a stationary installation?" is ... because that's what the environmental movement wants us to do.

Leading up to the 1970s, much of the electric power not produced by hyrdoelectric means was produced by burning coal, heating water, running a turbine to turn a generator.  Nuclear power was on the rise but environmentalists were convinced we would either blow ourselves up or live in a world of background radiation cause we didn't know how to dispose of the spent fuel rods.

At the same time, they discovered acid rain, a low acidic impurity in the atmosphere due to carbon release at coal fired plants eventually causing the formation of carbonic acid, in very low concentrations.

The environmental movement was able to shut down the development of nuclear power technology and insist that all coal fired plants be converted to oil fired plants which burned cleaner.

I agree, we should wake up and recognize gasoline and deisel should be used for ground transportation.  Grades of petroleum that can not be used for transportaiton fuel should be used for other well suited purposes and we whould generate our power without petroleum when we can.  If all the government regulations were eliminated that interfered with the proper allocation of resources, I wonder what the market solution would be?

RE: What if.. solar cells

Dinosaur:  if the cost assigned to atmospheric discharges was zero, and government regulation were removed, the "free market" solution would be to burn the cheapest coal you could find.  Or to burn hazardous waste or garbage.

There's a role for regulation and for taxation:  the market doesn't price stuff properly, especially in situations where one person's consumption results in costs for others.

RE: What if.. solar cells

agreed Molten, look at China.

A close second would be neclear if we didn't have all the regulations, look at Europe.

RE: What if.. solar cells

Of course, reducing consumption will minimise the amount of solar cell area required.  More efficient lighting, heating, etc are currently available with future improvements likely.  Hot wire vs LED lighting anyone?

RE: What if.. solar cells

I agree that there is a role for government regulation.  For example, I work in transportation infrastructure (e.g. a highway department), and I believe speed limits need to be established and enforced.  Many folks think that is an unnecessary encroachment into their freedom.  In this free country, they have a right to their opinion even when it is wrong.

Likewise, I believe there are limits in polution that need to be established.  My problem is that there are severe government restrictions in some aspects of energy that do not apply to other areas.  This is an area where politics severely interferes with the proper allocation of resources.

For my part, I am outraged that China polutes the way it does while the environmental movement makes little to no fuss over their behavior.  Likewise, the European community that uses a large amount of nuclear power and permits their automobiles to generate much more polution than US automakers are permitted in this country, points the finger at the US as the principle player in global polution problems.  Environmental outrage directed at the US is dishonest given these facts.

If we could play by European rules, we would have much more nuclear power, reducing polution and the strain on global petroleum assets.  When I ask for governmental regulatiions to be lifted in order to permit the proper allocation of resources, I am speaking of the arbitrary rules that have shut down the nuclear power industry, and other capricious rules that permit poluting by some folks but restrict poluting by others.  Level the playing field and let engineers figure out where the resources should be used.

Dave, do you have a figure on lumens/watt on LED- incandescent-florsecent lights?  I'd like to know how those compare.  They are using a lot of LED matrix signal lights in my area now.  I like them because they are redundant.  I suspect they are also efficient.  I just don't know to what degree.

RE: What if.. solar cells

LED lights?  Can't give you any real numbers, but they have transformed the bicycle lighting industry.  Rear, red lights have been available for a few years and only need one set of batteries for the whole Winter.  Practical white lights came out over the last couple of years and are looking similar - my old "hot wire" front took 6 (!) batteries and lasted a week or so.  My new LED takes 4 and just keeps going on and on.

RE: What if.. solar cells

(OP)
" Likewise, the European community that uses a large amount of nuclear power and permits their automobiles to generate much more polution than US automakers are permitted in this country, points the finger at the US as the principle player in global polution problems. "

Oh, have you got figures for the pollution emitted by European and USAn automobiles? I am intrigued by your claim.

Also, what are the relative contributions to global pollution?

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

RE: What if.. solar cells

Quote:

Likewise, the European community that uses a large amount of nuclear power and permits their automobiles to generate much more polution than US automakers are permitted in this country

Dinosaur, I'm with Greg.  I'd be interested to know on what basis you make your claim to see if I'm wrong.

Based on my limited experience I'd say the average mpg for vehicles in most of Europe is a lot higher than for the US.  Less SUVs and a lot more small (sub compact) cars.

http://www.cemt.org/online/council/2000/CM0006Fe.pdf does show slightly lower emission standards in the US from around 2005 for NOx and particulates.

I couldn’t find anything definite for comparative average mpg between the US & Europe but strongly suspect Europe is somewhat lower.  

http://en.wikipedia.org/wiki/Fuel_efficiency
http://en.wikipedia.org/wiki/Fuel_economy_in_automobiles

The second link does give

Quote:

The average fuel efficiency of European cars is over 40 mpg, of Japanese cars 45mpg, and North American cars 20.4 mpg
allthough it doesn’t cite a reference It sounds a reasonable estimate.

Also on the nuclear power front, yes France uses a lot but I don't think the rest of Europe is particularly high and doubt the French tip the balance that far.  

http://en.wikipedia.org/wiki/Nuclear_energy_policy

I suspect the % of European energy from nuclear is a little higher than the US but not by as much as you imply.  Interestingly the US is the largest producer of Nuclear power though it is only around 20% of its total electrical consumption.

RE: What if.. solar cells

KENAT and Greg,

This is why I have the opinion that European Cars don't meet our emmision standards ...

Imported motor vehicles are subject to safety standards under the Motor Vehicle Safety Act of 1966, revised under the Imported Vehicle Safety Compliance Act of 1988; to bumper standards under the Motor Vehicle Information and Cost Savings Act of 1972, which became effective in 1978; and to air pollution control standards under the Clean Air Act of 1968, as amended in 1977 and 1990. Most vehicles manufactured abroad that conform with U.S. safety, bumper, and emission standards are exported expressly for sale in the United States; therefore, it is unlikely that a vehicle obtained abroad meets all relevant standards. Be skeptical of claims by a foreign dealer or other seller that a vehicle meets these standards or can readily be brought into compliance. Nonconforming vehicles entering the United States must be brought into compliance, exported, or destroyed.

Note the emissions control standards.  I have been told more than a few times that you can't just drive a European car in this country because it doesn't meet out emission control standards.  Once you make it meet our standards, it is essentially a US car.  We have been meeting this air quality standard since the late 1960s.  That's why I say I want them to come up to our standards before they have anything to say about us.

RE: What if.. solar cells

Your statement was:

Quote:


Likewise, the European community that ..... permits their automobiles to generate much more polution than US automakers are permitted in this country

For certain emmisions, as I stated in my post, the US has lower limits.  However, the average european mpg is around double that of US vehicles.  So for CO2 and water vapour I assume the average euro vehicle is correspondingly lower per mile.  Obviously not everyone considers CO2 & water vapour pollutants but certainly reduced fuel use does have an impact on the environment.

Quote:

If we could play by European rules, we would have much more nuclear power, reducing polution and the strain on global petroleum assets.

Or you could just drive vehicles with European/Japanese levels of efficiency and reduce the strain on petroleum that way.

So you feel europeans should meet your emission standards for certain specific chemicals before they say anything about you, while europeans probably feel you should meet their levels of fuel efficiency before you impune them.

RE: What if.. solar cells

and so we have strayed from the OP to a trans-atlantic slugfest

RE: What if.. solar cells

Except that I'm not impuning anyone.  I'm defending the US from unwarrented character attacks.

Comparing US and European cars on MPG is once again comparing apples to oranges.  The US does not have the population density of Europe and that is the basis for many differences between US and European culture.  My European friends living in the US are quite happy with most things american.  My British friend, in particular, is more upset with the folks who don't notice the light has changed to green.  He drives a bigger car than I do though.

RE: What if.. solar cells

... maybe given the lower population density, the US could cover the spare land with solar cells.  Large parts of it are unpopulated and get lots of sunlight.  I would have thought that Nebraska & Colorado could power the whole country.  (just trying to steer the thread back to the OP).  Australia could power the whole World.

RE: What if.. solar cells

(OP)
Dinosaur, numbers, not opinions.

Back on topic.

There are various proposals for photoelectric power stations. At the moment they are a pretty expensive option, something like 4 times as expensive per kWh as coal powered stations. But, if the price of cells drops, that suddenly looks like a good idea. Somebody has conned the Victrian government into subsidising a fairly large PV station.

Here's another one. The peak load on the electricity grid is typically on hot afternoons when everybody switches their A/C on. So, if cells dropped a fair bit in price, why not power A/C from local solar cells? When the sun is shining is when you need the AC. Peak load electricity is the most expensive, and is typically from gas turbines, so even though this is not a great way of using the cells (much better to install a proper domestic PV plant) it may be more cost effective.

Cheers

Greg Locock

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.

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