Could solar panels ever be feasible?

[DC]

The other way in which solar technology could easily achieve parity is if it meets other requirements. Say we never get any better with efficiency or per-unit cost, but we make them robust and flexible enough to serve as roofing material -- waterproof, insulating, fire-resistant, etc. It'd become standard practice overnight.

No good engineer misses an opportunity to satisfy multiple requirements. When this will occur for solar, however, I can't guess, but I believe it will happen.

a very good point

 

[DC]

i see alot talking about efficiency.
incandescent lamps are very inefficient. when i remember correctly, 70% of energy is converted to heat and only 30% for light, and afaik it is still the most used one.
While we have alot more efficient Compact fluorescent lamps and my experiance so far is, they are even cheaper because tey dont brake as often as incandescent lamps.

i think the point that solar panels are only converting a part of the energy is actually not a real point.

 

[Confuseling]

Again, it really depends what you're doing with it. If you intend to blast it into space, a 1% reduction in efficiency could well be a showstopper. But if you can make it 20% of the cost and produce 20% of the power, it might well be useful to just print reams and reams of it and coat buildings (perhaps even roads) in it. At a certain point it has more to do with not minding if it gets broken, rather than efficiency.

 

[Cuddles]

Many many small power generation centres rather than very few big ones.

I think one big problem with these kind of discussions is that far too many people see this as a dichotomy. What we actually need is both. Distributed generation has some advantages and is a great idea for some purposes, but there are other things that really need large, centralised generation as well. And it's not just users who may find distributed generation less than ideal, there are many ways of generating power that benefit greatly from economies of scale, and are often not even possible on a small scale. Nuclear, geothermal and tidal power, for example, all need large, central facitilities, and are likely to be three of the major contributors to power in the future. Covering buildings in solar panels and wind turbines is a nice idea, but even if it turns out to be practical, it will never be the whole answer.

 

[Confuseling]

Additionally, if we manage to sort out room temperature superconduction, it ceases to matter where you make power to anywhere near the same extent...

 

[GreyICE]

i see alot talking about efficiency.
incandescent lamps are very inefficient. when i remember correctly, 70% of energy is converted to heat and only 30% for light, and afaik it is still the most used one.
While we have alot more efficient Compact fluorescent lamps and my experiance so far is, they are even cheaper because tey dont brake as often as incandescent lamps.

i think the point that solar panels are only converting a part of the energy is actually not a real point.

Well at least your math is consistently quite terrible.

Incandescents would rock if they were 30% efficient. If they were that good we could kick back and never worry about them. Hell, if they were that good, they'd nearly violate the laws of physics.

They're 4% efficient. Tops.

Gas Discharge occasionally push near 30%, but not often. Most of the florescent you buy for your home or 15% or less. Theoretical maximum efficiency on a white light source is ~35%, so if the light is white, it ain't better than that, and you can bet your bottom dollar it isn't meeting theoretical max.

 

[quarky]

I lived with pv electricity for many years. The alternatives happened to cost more where I lived. Great technology, yet also disspointing. The panels never put out the max rating. losses abound. Batteries were problematic. A light dusting of snow meant a blackout, unless I climbed the roof and swept it off.

But I loved the way that that power source made us hone in on our useage, through efficient appliances and behavior. The panels were good for 25 years. Not so for the batteries.

 

[Boran]

I agree with meeting halfway. If you live in a somewhat cold or hot climate insulation should be your first priority. Heating and cooling are major energy consumers and investing in insulation earns itself back on a way shorter term than solar panels at the moment.

 

[Kaylee]

@ the OP: I think the technology is here now. I don’t believe that New Jersey, USA is known for being a particularly sunny location, but some NJ home owners have installed solar panels to offset the majority of their monthly electricity bill. From a 3-year old Wall Street Journal article:

Tired of paying $140 a month in electric bills, Frank Corradi decided to do something about it. So last December, he had part of the roof on his four-bedroom colonial covered with solar panels.

Today his suburban Cedar Grove, N.J., home is a mini power station. Not only does it produce enough electricity to run the household, it also generates about $170 in cash roughly every six weeks for Mr. Corradi under a state program that rewards developers of clean energy. "That's a treasure sitting up there on my roof," says the 43-year-old financial analyst.

$170 over 6 weeks prorates to $113.00 and change over 4 weeks. So, per the above Wall Street Journal article, Frank Corradi’s monthly electric bill drops from $140 to $27.00 a month because of his solar panels. ( ETA: Oops! I misread the article. This is partially because at a "green party" I went to over the summer, I met a contractor who designs systems just powerful enough to offset costs but not generate cash flow. IIRC, he did this to minimize the amount of cash the home owner would have to outlay for the system. But in the WSJ article, the home owner who was interviewed made a different choice.)

It’s an expensive project and for many homeowners part of what makes it feasible is whether they live in a state that offers grants and tax rebates, and also whether they live in state where loans are available to cover part of the home improvement project.

Mr. Corradi's project, which cost about $50,000, would have come at about twice that amount just a decade ago. In addition, various incentives covered more than two-thirds of his out-of-pocket costs. Incentives such as these are expanding quickly and are now available in more than 30 states, including California, New York and Texas, up from just four in 1999. (A list of states and incentives is at dsireusa.org.)

Another important consideration is whether local laws enable home generators to sell their electricity back to the local utility. Known as "net metering" clauses, such regulations are critical for someone who wants to install photovoltaic panels on their home (or, for that matter, any other form of electrical generator, such as a windmill). Not only does net metering enable a homeowner to sell excess power back to the utility, it also enables a homeowner to draw power from the utility at times when the solar panels aren't generating enough electricity. (Such as when it is dark outside.)

Thirty-nine states mandate net metering. But even some sunny states don't, including North Carolina, Missouri and Nebraska.

 

[mhaze]

...For common everyday electricity use (say, at least 30-40% homes) to contribute significantly (at least 40% of energy demand) to society? ....What say you?

No, most countries doing heavy solar/wind figure max alt. energy at 10-20% of demand due to grid issues.

 

[GreyICE]

No, most countries doing heavy solar/wind figure max alt. energy at 10-20% of demand due to grid issues.

Max current, max theoretical at some point in the future, maximum grid usage in Norway, whatever do you mean? Are these numbers as quality as the 30% efficient incandescent lightbulbs?

 

[Ashles]

I am awaiting the day when every suburb, neighbourhood, or even home has its own power generation that feeds into the grid. Diversification is the key. Many many small power generation centres rather than very few big ones. A friend of mine had an idea - a small wind turbine on the top of every street light, all feeding into the grid.

We have the technology today to start doing things like this. Why aren't we?

I think there are 2 discussions:
The energy production discussion - in which case I agree, the more sources of renewable energy the better
The ecological discussion - here I am more uncertain. Obviously solar panels and wind turbines do not grow on trees and do not last for ever. I have read conflicting details of what the net industrial impact is of building solar panels and wind turbines (and other such generators).
The industry involved in constructing, fitting and maintaining such devices is only worth it if they last long enough to output a net reduction in ecological impact.
As far as I am aware it is debatable whether we are there yet with wind turbines and we are almost certainly not with solar panels. But I am interested if this is not case.

 

[ponderingturtle]

You can electrolyse water. Or even heat it up. If you get a reservoir containing millions of litres of water, and heat it up by a degree or something, that's an incredible amount of energy, and will happily sit there waiting to be extracted again without causing any harm to its surroundings - or indeed whoever ultimately ends up drinking it.

You then are taking a major hit in efficiency.

One practical way of storing energy I heard of from sun was storing compressed steam during the day and using it to turn the turbines at night. Might not be practical, but at least it can in theory be pretty efficient.

 

[ponderingturtle]

You can electrolyse water. Or even heat it up. If you get a reservoir containing millions of litres of water, and heat it up by a degree or something, that's an incredible amount of energy, and will happily sit there waiting to be extracted again without causing any harm to its surroundings - or indeed whoever ultimately ends up drinking it.

You then are taking a major hit in efficiency.

One practical way of storing energy I heard of from sun was storing compressed steam during the day and using it to turn the turbines at night. Might not be practical, but at least it can in theory be pretty efficient.

 

[Kaylee]

I don’t believe that New Jersey, USA is known for being a particularly sunny location, but some NJ home owners have installed solar panels to offset the majority of their monthly electricity bill. From a 3-year old Wall Street Journal article:

I lived with pv electricity for many years. The alternatives happened to cost more where I lived. Great technology, yet also disspointing. The panels never put out the max rating. losses abound. Batteries were problematic. A light dusting of snow meant a blackout, unless I climbed the roof and swept it off.

Sounds like there would be a demand for roof wipers! (sort of like wind shield wipers, but larger)

But I loved the way that that power source made us hone in on our useage, through efficient appliances and behavior. The panels were good for 25 years. Not so for the batteries.

No, most countries doing heavy solar/wind figure max alt. energy at 10-20% of demand due to grid issues.

I think there are 2 discussions:
The ecological discussion - here I am more uncertain. Obviously solar panels and wind turbines do not grow on trees and do not last for ever. I have read conflicting details of what the net industrial impact is of building solar panels and wind turbines (and other such generators).
The industry involved in constructing, fitting and maintaining such devices is only worth it if they last long enough to output a net reduction in ecological impact.
As far as I am aware it is debatable whether we are there yet with wind turbines and we are almost certainly not with solar panels. But I am interested if this is not case.

This seems to contradict Mr. Corradi's results as quoted above where his solar panels produce enough electricity to cover all of his home electrical needs AND give him a monthly income of $113.00 (170*4/6).

What’s the probable explanation? Is he being overpaid by the utility company? Did the reporter just get the wrong facts? Is the reporter not taking into account the amount of energy needed to produce the panels? Or are NJ utility companies using a different system that is more efficient? Have batteries that store energy from pv sources improved since the ones quarky used? Or other possibilities?

Just curious as I’m not an engineer.

 

[GreyICE]

Sounds like there would be a demand for roof wipers! (sort of like wind shield wipers, but larger)

Compressed air would do the trick for a light dusting, for a very heavy load, mechanical movement would be necessary.

This seems to contradict Mr. Corradi's results as quoted above where his solar panels produce enough electricity to cover all of his home electrical needs AND give him a monthly income of $113.00 (170*4/6).

What’s the probable explanation? Is he being overpaid by the utility company? Did the reporter just get the wrong facts? Is the reporter not taking into account the amount of energy needed to produce the panels? Or are NJ utility companies using a different system that is more efficient? Have batteries that store energy from pv sources improved since the ones quarky used? Or other possibilities?

Just curious as I’m not an engineer.

Reality always trumps theory. If the theory is not predicting the reality, the theory is incomplete, incorrect, or in the case of Mhaze's "statistics" non-existent.

 

[Confuseling]

To be fair though, there are an awful lot of variables. And it's true to say that the present power grid is designed more or less as a 'hub and spoke' system of centralised production and trunk distribution, where microgeneration would be distributed, and look almost totally different. Patching microgeneration into the present system can be awkward, because the infrastructure is far from ideal - but the plus side is that means if we're serious about it, there are probably major efficiency gains to be made.

 

[linusrichard]

You know the answer to this: money.

Who is going to finance the initial installation? Your government? (hollow laugh)
Your local power company? Only if they can meter it and charge you for it.

Why couldn't they meter it and charge you for it? They could lease your roof for a small fee, put on their own solar panels, and then add the power to their grid, and sell it.

 

[Kaylee]

Why couldn't they meter it and charge you for it? They could lease your roof for a small fee, put on their own solar panels, and then add the power to their grid, and sell it.

Interesting. Sort of like during the 1960s when Ma Bell owned the telephones in your home and charge you a monthly rent for them.

 

[Kaylee]

Compressed air would do the trick for a light dusting, for a very heavy load, mechanical movement would be necessary.

Cool. Probably also good for removing autumn leaves.

Reality always trumps theory. If the theory is not predicting the reality, the theory is incomplete, incorrect, or in the case of Mhaze's "statistics" non-existent.

Well the reality, according to the WSJ in 2005, was that solar panel installations were growing -- so I would have to assume that at least some home owners found it worthwhile. The same article also mentioned net metering in 39 of the 50 states -- so, presumably at least some utility companies installed the hardware to allow for microgeneration of electricity to be shared in the grid.