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its easy to debunk this myth.

Let's just say, for the sake of argument, that it takes 100 units of energy to make a PV panel. Then according to this myth, the panel only ever produces, say, 90 units of energy. The manufacturer pays for the 100 units of energy + materials to make the PV, and then sells it to the consumer for a profit. The consumer who buys this product (at a price which already accounts for 100 units of energy) is able to save more money than was spent on the purchase with only 90 units of energy? This is clearly not possible.

Either, there is no monetary payback from PV panels, or the ER/EI is greater than 1. But both cannot be true simultaneously. And the data shows that ER/EI is, in fact, greater than 1.

Estimated times for energy payback, from various sources:
(pdf) "1 to 5 years
various sources for estimates, all 1 to 5 years
"in the worst case, 4 years"
"usually under 5"
"range from 1 to 4 years"

I disagree that nuclear power is a necessary risk or evil.

We have alternative energy technologies that in the long run cost less to construct and maintain while offering a higher ROI or return on investment. Putting all of our eggs in one basket probably isn't the best idea, so I feel strongly that diversification of energy technologies is necessary. Does that make me irrational? I don't think this debate needs to involve calling one side rational and the other something less than. What I will say is that nuclear energy is short sighted. Until we are capable of managing and securing the waste present globally and domestically, we should not be producing more. If we take the cost of waste and mismanagement into account, nuclear energy has been incredibly costly, in some respects the ability to measure its economic impact isn't even possible.

Mistakes haven't just occured in the technology's early years. From a purely economic perspective, I don't see this tech as a sound or green investment. The risks are far too great and history has shown us that it is not profitable. In addition the question remains: who is going to profit from the coming wave of non-nuclear sustainable energy infrastructure. The US has not lost its opportunity to reignite its industrial base providing these services and equipment globally, but Europe will soon outpace us.

If we want to ween ourselves from fossil fuels, we can do it with sources that are proving themselves in Europe today.

http://news.com.com/Home+wind+turbines+turn+fashio nable+in+Britain/2100-11392_3-6124730.html

http://news.bbc.co.uk/1/hi/scotland/3719868.stm

http://www.nrel.gov/

If you can, you might consider a hybrid system. In many areas of the country (such as here in central NJ), wind and solar complement each other well.

Solar works best in the peak summer months, but not as well given the shorter days and lower sun in winter. [Although there are also less leaves in winter and less water in the atmosphere, which helps since there's less blockage.] Sites like PVWatt http://rredc.nrel.gov/solar/calculators/PVWATTS/ve rsion1/US/code/pvwattsv1.cgi can help

Wind often works best in winter since wind speeds are higher during that time. Check the wind speed graphs of your local airport. http://www.city-data.com/city/Trenton-New-Jersey.h tml

What Steom is actually claiming is quite possible, but uninteresting. Steorn is making three claims for its technology:

1. The technology has a coefficient of performance greater than 100%.
2. The operation of the technology (i.e. the creation of energy) is not derived from the degradation of its component parts.
3. There is no identifiable environmental source of the energy (as might be witnessed by a cooling of ambient air temperature).

The coefficient of performance is not efficiency. It's the reciprocal of efficiency. Most refrigerators and heat pumps have a coefficient of performance greater than 100%. 200-350% is typical. The coefficient of performance of an ideal heat pump, and the efficiency of an ideal heat engine, both working between the same temperature difference, will have a product of 1.

So Steom can meet its claims with any off-the-shelf heat pump.

Since they talk about "magnetics" so much, they're probably fooling around with something exotic like a magneto-caloric heat pump. This is a cute idea that's been around for a while, requires very strong magnetic fields, is sometimes used for cyrogenic cooling, and has been considered for auto air conditioners. There are buzzword friendly papers like "Preparation of Superferromagnetic Lanthanide Nanoparticulate Magnetic Refrigerants" on the subject. If they've made that work, they may have something with product potential. Maybe. But it's not "free energy".

Water splitting microbes -
Check out here, here or here.

Guess, your guess is wrong.
Be a little less sarcastic next time.

it might be, except that isn't true about the solar cells.

http://www.nrel.gov/ncpv/energy_payback.html

That is an older reference, some newer techniques are even more efficient, and there's at least one solar "breeder' facility out there that uses solar PV to manufacture solar PV. One of the more unfortunate aspects of solar cell production is competition for silicon. Our society is choosing "spend it now, who gives a fuck about our future, our kids and grandkids can go screw themselves" frivolity like throw away obsolete graphics cards good for 6 months and throw away ipods obsolete every year and throw away cell phones obsolete every other month it appears and so on. Why, you just *must* upgrade to the next 5% better CPU and mother board combo because "work" demands it, or a videogame addiction, etc., and etc. If we had a slightly saner set of priorities solar PV would be a lot cheaper right (cheaper as in money and cheaper as in resources needed) now with the tech already developed.

But, slashdot group think is, it is much better to make billionaires into trillionaires, so by all means dis solar, support the corrupt (highly corrupt) overly expensive nuclear industry (despite solar being practical fusion power and actually more high tech than fission power and certainly deserving of MORE R and D than dirty fission power) never get any at all because "it's not cost effective yet", keep spreading that lie (that's been a lie for over 25 years now)that it costs more in energy than it ever will put out, and just complain about things while you improve your scores in the latest first person shooter.

Fission? Not enough uranium, unless you want to spread nuclear weapons technology around the world via fast breeder reactors.

Fusion? If anyone can ever get it to work, and what about all that dangerous radioactive tritium that's bound to leak out all the time?

Is anyone doing any research into quantum energy sources? What about tapping the Higgs field? Could there be a better way to utilize E=MC^2 than just making hot water to power a steam/turbine engine? There's got to be a better way to liberate the energy locked into normal matter. Who's looking into that?

NASA studied space based solar power in 1976 and again in 1995. They shelved it each time. Why? Why can't we tap the unimaginably huge amount of sun generated energy that's just wafting by between the Earth and the Moon? It's not a question of how- we know several ways how. It's a question of cost and politics. What technologies need to be improved, invented, or abandoned to make it cost competitive with coal? What politics can we get involved in? Are there even better solutions than solar power?

This company is apparently the spawn of TerraSun. They acknowledge this in the PDF mentioned above (http://www.nrel.gov/technologytransfer/entreprene urs/pdfs/prism_solar.pdf), slide 3 gives the company timeline and lists TerraSun.

The technology

I remember reading a report on wind a few years back saying that if the entire land surface of the earth was evenly coated with windmills (0.5 Km separation) we would meet approximately 20% of of our total power needs.

I'm sorry, but you're talking out of your ass. I can counter your report with several more credible reports that say covering the Dakotas, Nebraska, and Kansas completely with windmills would meet 100% of the United States energy needs, and that total wind potential globally exceeds global energy demand (cites here and here).

Nuclear is the most environmentally friendly way to go.

No, it's not. I'll concede that the designs of modern nuclear reactors and advances in fuel recycling have significantly decreased the negative environmental effects of nuclear energy, but not enough to declare it "the most environmentally friendly" energy source.

Energy efficiency and conservation should be the top priority of any sane energy policy, beginning with improvements in generation efficiency and transmission. 67% of the energy output of power plants is lost in conversion to electricity, and another 9% is lost in transmission and distribution (graph). Eliminating even a fraction of that loss could eliminate the need for new power plants for decades.

"It's solar power that has the problem you mention with panels not producing as much power as was required to build them."

That is completely wrong. I really wish people would stop spreading this lie, it comes up every time renewable energy is discussed. It might have been true 30-40 years ago, but certainly not anymore. For modern PV, the energy payback is generally 1-4 years. For panels that last 50+ years, that is a small tradeoff.

I can list 100's of references, but this one sums it up well.

http://www.nrel.gov/docs/fy04osti/35489.pdf

To quote the article:

"Indeed, researchers Dones and Frischknecht found that PV-systems fabrication and fossilfuel energy production have similar energy payback periods (including costs for mining, transportation, refining, and construction)."

Well, the H2 Prius can get projected 100 miles (Hydrogen ICE vehicle) & reality ~80 miles to a two-H2-canister tank!

In decades-long tests the fully-developed technology of single- and poly-crystal modules has shown to degrade at fairly steady rates of 0.5% to 1% per year. First-generation amorphous modules degraded faster, but there are so many new wrinkles and improvements in amorphous production that we can't draw any blanket generalizations for this module type.

The first thin films, made of copper sulfide, suffered from an electrochemical instability that led to degraded performance. Copper sulfide never became a commercially significant thin film. The second commercial thin film, amorphous silicon, suffers from a serious degradation associated with (of all things) exposure to light. Called the Staebler-Wronski Effect, it results in about a 20%-40% degradation unless checked by design modifications such as thinner intrinsic layers and the use of multijunctions.

The other side of the lake has more wind.

You are WAY off with your typical rush limbaugh sourced "payback" figures. here, have a look. That 10-20 year figure is from like 30 years ago, and people still keep quoting it, never bothering to actually go and look. Believe it or not, tech keeps advancing, even when you aren't looking.

I lived for a long time with pure solar power. You can easily run a normal house with a normal amount of electricity from what can be mounted on the roof, given a good open southern exposure in some place reasonably sunny, which is 3/4ths or more of the land mass of the US. And wind power is even cheaper if your locale supports it, which, again, is a huge area of the US, probably between 1/2 and 2/3rds of the land mass. And that is at todays prices and with todays tech, who knows what kilowatt hours will be costing you 5 years from now. They might rise enough to decrease "payback" figures by a significant amount, and if you go bu past historical cost data, you can just about bet your rate will be going up from your friendly electric company. Those tables and maps for solar and wind potential you can go google up yourself, easy enough to find, I found the "solar payback" site for you with ten seconds worth of search.

And yet they are wrong!

http://www.toolbase.org/tertiaryT.asp?DocumentID=3 216&CategoryID=949
"Paybacks vary widely, but you can expect a simple payback of 4 to 8 years on a well-designed and properly installed solar water heater."

http://www.nrel.gov/ncpv/energy_payback.html
"Paybacks for multicrystalline modules are 4 years for systems using recent technology"

There's a lot of BS flying on both sides of the debate, but the reality is that PV is a good solution for many problems.

Kyocera powers their entire solar panel plant on PV.

Yeah, there is nothing new about this, I think this is some kind of a slashvertisement. The technology that OTEC has been developing in this field is interesting. Hopefully it will ultimately pan out.

Here's where I have seen more about this technology before:

http://www.wired.com/wired/archive/13.06/craven.ht ml

http://www.nrel.gov/otec/

Enjoy :)

In order for peanuts to be an economically viable biodiesel fuel, the energy produced by biodiesel use has to be greater than the energy consumed to make the biodiesel.

EROEI (energy return) for biodiesel production through soybeans is currently roughly 3.2 to 1 according to a widely cited U.S. Department of Energy study, and it has nowhere to go but up as new vegetables are experimented with and the process is refined. Particularly, soy is thought to be far from ideal for producing biodiesel.

(Lets not even consider a shortage of farmland available for FOOD.)

The hunger problem isn't a food production problem as much as a distribution problem, as warlords and dictators manipulate food supply to control the people on their land. (Analogy is to air in Total Recall.) Besides, it's still possible to make biodiesel from used vegetable oils, letting McDonald's customers subsidize the oil that goes into biodiesel (and into the tank of diesel vehicles whose engines have been modded to run on straight vegetable oil).

the dollar is king.

You must mean "the euro dollar is king," as look at how much the dollar has fallen over the past five years.

Maybe YOU should get off your pessimistic ass and read a little more. Less than have a million acres of land could produce the equivalent of 10 BILLION gallons of oil.
http://www.nrel.gov/docs/legosti/fy98/24190.pdf
Biodiesel CAN scale, easily.

Premptively, let me make this very clear so we don't need to have the same discussion everytime biodiesel comes up.

First, biodiesel has a positive energy balance, to the tune of about 3.2 units out for every unit you put in. http://www.nrel.gov/docs/legosti/fy98/24089.pdf

Second, biodiesel is 78% carbon neutral with regard to greenhouse gas emissions (see previous pdf). That is because the majority of the carbon emitted when you burn a gallon of biodiesel was captured from the atmosphere when you grew the plant to make the vegetable oil. However, the methanol used to make the biodiesel (fatty acid methyl ester) is made from natural gas, at least in the US. You could make 100% renewable ethyl ester biodiesel from ethanol, or make methanol from landfill recovery biogas, but we don't currently.

Third, soy and corn oil are crummy crops to make biodiesel from. But that's where the lobbying money is right now. Other plants have much higher yields.
http://journeytoforever.org/biodiesel_yield.html

Forth, no, it isn't a question of "food or fuel"? We can do both! Whenever you hear that argument ask yourself whether the person is well meaning but misinformed, or as been happening recently, is part of astroturf campaign to preserve the status quo of the petroleum economy.

Want to try making some biodiesel yourself?
http://www.biodieselcommunity.org/howitsmade/

Already making biodiesel and want to show it off?
http://www.cafepress.com/RenewableWear

Exactly. If auto users had to pay the real cost of pollution and environmental impact, they would choose to purchase vehicles with better mileage and lower pollution. These taxes should specifically subsidize publicly-funded energy research, such as the National Research Energy Laboratory http://nrel.gov/ .

Just to reiterate, Watts are a dynamic measurement. Watt-hours is a static measurement. What you're really asking is how many Watts this design is able of producing.

That figure is most dependent upon location, average windspeed, and the size of the unit. You can use maps such as the Wind Resource Atlas of the US to determine available wind power in Watts/Meter^2. Multiply that figure by the area of the unit, in square Meters, and multiply by the unit's efficiency (40%), and you get average power output in Watts.

Just to have something to go by, as others have said, a small unit can put out around 100 Watts in average winds.

http://www.nrel.gov/ncpv_prm/pdfs/papers/54.pdf

It doesn't look like its just made-up.

The U.S. Department of Energy's National Renewable Energy Laboratory did a feasibility study on these types of floating turbine farms and found that they could be built using existing technology and provide electricity at approximately $0.05/kWh. The turbines studied did not include the battery storage and hydrogen production described in the article above.

A little known fact is that it takes more energy to manufacture a turbine...

It's little-known because it's NOT a fact. Got a source? Here's what you're looking for. For every $1 you spend building and installing a wind turbine, you'll get $6-$80 worth of energy out of it over a lifetime. Compare that to $7-$29 for coal, $11-$60 for nuclear, and, contrary to popular myth, $4-$12 for solar. Then there's the fact that the Dutch found it economical to build turbines for centuries, long before the massive increases in efficiency we've seen in the past 20 years. Also, have a look at the graph on page 18 of the August, 2005 issue of National Geographic...

Substituting 100% biodiesel (B100) for petroleum diesel in
buses reduces the life cycle consumption of petroleum by
95%. This benefit is proportionate with the blend level of
biodiesel used. When a 20% blend of biodiesel and
petroleum diesel (B20) is used as a substitute for petroleum
diesel in urban buses, the life cycle consumption of
petroleum drops 19%.

In our study, we found that the production processes for biodiesel and petroleum diesel are almost identical in their efficiency of converting a raw energy source (in this case, petroleum and soybean oil) into a fuel product.

Biodiesel yields 3.2 units of fuel product energy for every
unit of fossil energy consumed in its life cycle. The
production of B20 yields 0.98 units of fuel product energy
for every unit of fossil energy consumed.

By contrast, petroleum diesels life cycle yields only 0.83 units of fuel product energy per unit of fossil energy consumed.

Just a curosity question (I don't know much about the details of this process) but I was wondering if it might be more efficient to replace the battery component of a solar car with a fuel cell arrangement, and have any excess solar power available split water into hydrogen and oxygen? http://www.nrel.gov/hydrogen/proj_production_deliv ery.html#split I know batteries are a major source of weight issues, but I don't know how H2O splitting compares in terms of energy recovery to battery storage. Anybody happen to know if the tradeoff could be advantageous?

Doing the research for you... http://www.nrel.gov/ncpv/pvmenu.cgi?site+ncpv&idx= 3&body=faq.html Says 1 to 4 years ENERGY payback. Since the PV panels are warranted for 25 years, that certainly looks like a net positive to me. Research before you spout lies.

According to the National Center for Photovoltaics, only 7% of the surface area's of cities have to be photovoltaic to supply _all_ power.

Don't underestimate the power of the future solar rooftop.

Close to the bottom of the page, a conservative figure...

Also here in the first paragraph...from this estimate, 27 years x 365 days = 9,855 times as much energy as we currently use.

Also here, here, and here.

Bottom line is that solar is possible today if we can ever wean ourselves off of oil (and keep the oil dependent businesses from buying off congress). (a lot of tree hugging rhetoric here but they have a point none-the-less...search for "oil lobby" to find relevant comments)

Lie.

What I have see are numbers that make the whole proposition somewhat marginal without advances in genetics of algae.

To get an idea of what you are going to get out an optimal system (using Calchemy's Unicalc):

50$/barrel_oil; 50gm_algae/(m^2*day); .8gm_oil/cm^3; .6gm_prepressed_oil/gm_algae; .7gm_oil/gm_prepressed_oil?$/(acre*month)

= 1016.17 $/(acre*month)

Please check for any errors, but it appears that under optimal conditions, meaning a sunny desert with warm nights year round and algae production consistently at the height achieved by ASP during their 20 year study, using a species modified to produce optimal oil and a consistently high price for oil, one can get $1000 per acre per month.

We have $1000/month to make this realistic and to pay the rest of the expenses of the operation per acre.

A covering will eat into that $1000 in two ways:

1) Amortization (which has to be fast)
2) Solar flux reduction

Let's take out the solar flux from the covering first and say we lose 30% leaving us with $700 for the rest of the operation. Let's further say that we need half of that for expenses other than structure amortization, leaving us with $350. If we assume commercial lending rates of around 12% and zero amortization -- just debt service, we can afford $35,000 to cover an acre so with amortization it drops to sometning more like $10,000 to cover an acre.

Covering these ponds sounds problematic under optimal conditions, let alone constructing bioreactors -- and we haven't even gone to climates with less total solar flux.

Recalculating for volumetric production of oil:

50gm_dry_algae/(m^2*day); .8gm_oil/cm^3; .6gm_prepressed_oil/gm_dry_algae; .7gm_oil/gm_prepressed_oil?gal/(yard^2*month)

= 0.17636 gal/(yard^2*month)

What this says is that the best you can expect, under optimal species and growth conditions, of any algae-oil system that relies on the sun for its energy, is for each square yard of solar-exposed pond to produce just over a fifth of a gallon of pressed lipid oil each month -- which you must then process into biodiesel through the normal methods. If you find other energy sources you can feed to algae, you might beat this but algae are optimized to consume solar energy so you have to be very skeptical of any claims that exceed this productivity level and really find out where the energy is coming from and how the algae are metabolizing it.

Let me try to break down the parameters of the calculation:

50gm_dry_algae/(m^2*day)
This is the target productivity figure given by the National Renewable Energy Laboratory's review of the last 25 years of algae biodiesel work. It basically says for a given area, how much dry algae you should be able to get out of an _optimal_ system per day -- optimal climate, species, solar flux at pond surface, etc. If you can economically create these conditions in your "back yard" then you can get that level of productivity. Find the NREL's review at:
http://www.nrel.gov/docs/legosti/fy98/24190.pdf

.8gm_oil/cm^3;
This is the density, or specific gravity of diesel. Diesel isn't quite as dense as water. This probably should have been the density of lipid oil but I didn't have that figure handy.

.6gm_prepressed_oil/gm_dry_algae;
The _highest_ oil content, of oil-producing algae reported by the National Renewable Energy Laboratory's review, was 60%. This presumes algae grown under their high rate goal of 50gm_dry_algae/(m^2*day) but this growth rate has yet to be achieved with this high, 60% oil content (to the best of my current reading of the NREL report).

.7gm_oil/gm_prepressed_oil
This is a fairly optimistic 70% fig

Never been made to work though...

My father just finished building a house in Ky. of all places that uses a geothermal heat pump to reduce costs of heating/cooling. While he does not see 90% efficiency, he does see around 40-50% efficiency; a substantial savings in a house 4100 square feet in size. To put that in perspective, his heating/cooling costs are very close to mine while my house is about 1/3 the size of his -- 1400 square feet. The theories behind the ocean water pumps and his heat pump are very similar. You can find out more here.

http://rredc.nrel.gov/solar/old_data/nsrdb/redbook /sum2/23183.txt

(Why is /. mangling this URL, at least in preview?!?) I double-checked, but it appears that these figures are indeed in kWh/m^2/day.

"I've read that it costs $8000 (of course in US dollars, you godless heathen!) to replace the batteries for electric and hybrid cars. And furthermore, they need to be replaced every three years. "

Err... NO...

First, Toyota warrants the expensive nickel-metal hydride (NiMH) Prius batteries for 10 years and 100,000 miles (160,930 km), and Honda warrants the batteries on the Civic Hybrid for eight years and 80,000 miles (128,744 km). Note: In California, there is no millage limit. For the most part Hybrids limit the State of Charge of the NiMH Battery pack which extends life cycle considerably. And a very good reason why they can offer these long warranties without losing their shirt.

Second.. the NiMH hybrid battery packs aren't all that big.. around a 100 lbs. You could build a replacement NiMH pack for about a dollar per watt or around 1500$. As volume ramps up, one should expect the price of the components to drop even further.

Solar cells take almost as much energy to make as they put out over their lifetime.

• Multicrystalline: 3.7 years
• Thin film: 3.0 years
• Multicrystalline, anticipated: 2.1 years
• Thin film, anticipated: 1.1 years

Those figures you're looking at are per day. See here for an excellent set of maps.

Biodiesel has been energy-positive for quite some time now. It doesn't yet allow for making a profit, though, at least not with U.S. fuel prices. Maybe in europe. Check out "Energy Balance/Life Cycle Inventory for Ethanol, Biodiesel and Petroleum Fuels". Specifically, "the energy yield of biodiesel is (3.2/0.83) 280 percent greater than petroleum diesel fuel". You could also read the cited paper, "Life Cycle Inventory of Biodiesel and Petroleum Diesel for Use in an Urban Bus". (PDF) The significant paragraph follows:

Energy Balance. Biodiesel and petroleum diesel have very similar energy efficiencies. The base case model estimates life cycle energy efficiencies of 80.55% for biodiesel versus 83.28% for petroleum diesel. The lower efficiency for biodiesel reflects slightly higher process energy requirements for converting the energy contained in soybean oil to fuel. In terms of effective use of fossil energy resources, biodiesel yields around 3.2 units of fuel product energy for every unit of fossil energy consumed in the life cycle. By contrast, petroleum diesel's life cycle yields only 0.83 units of fuel product energy per unit of fossil energy consumed. Such measures confirm the "renewable" nature of biodiesel. The life cycle for B20 has a proportionately lower fossil energy ratio (0.98 units of fuel product energy for every unit of fossil energy consumed). B20's fossil energy ratio reflects the impact of adding petroleum diesel into the blend.

In other words; biodiesel has very slightly lower energy density but far superior return as compared to normal diesel. The PDF also describes emissions, which are better on biodiesel.

Yes you need to replace them sometime after 20+ years. In order to curb this waste people are working on organic solar panels to both bring down the cost of solar and reduce the environmental impact that the panels have when thrown away.

There are much better ways of storing the energy than using battery banks, especially when you don't have to carry the storage around (think cars). Many places hydro-electric power and solar cells could be run togehther very efficiently. Shut down turbines and save water in the reservoire when there is much sun, restart them at night.

Waves are cool, but don't forget ... OTEC (Ocean Thermal Energy Conversion)

My father was a primary designer on this, so I had the "real scoop" on what was going on there in real time, it was real exciting stuff back then!

Mini-OTEC, 1979

In 1979, the first successful at-sea, closed-cycle OTEC operation in the world was conducted aboard the Mini-OTEC, a converted Navy barge operating in waters off Keahole Point.

This plant operated for three months, from August-October 1979, and generated approximately 50 kilowatts of gross power with net power ranging from 10-17 kilowatts.

Its turbine generator produced a gross output of up to 55 kW. About 40 kW were required to pump up 2,700 gallons/min of 42F water from 2200-ft depth through a 24-in diameter polyethylene pipe and an additional 2,700 gallons/min of 79F surface water, leaving a maximum net power output of 15 kW.

This was a joint effort by the State of Hawaii and a private industrial partner.

More linkage: NREL's OTEC site

Google

http://www.nrel.gov/docs/fy04osti/35489.pdf

They even have their sources in it.

Conventional cells are currently at 3 to 4 years payback according to this DOE FAQ.

I did some research work when I was a physics student, and I took data for a bunch of researchers at the National Renewable Energy Labs back in the mid-nineties. My specific project was working with a new CdTe based thin-film material to be used in solar cells. It was so easy to deposit on glass substrates that we referred to it as "painting the glass." This made it very easy to mass produce.

However, the new material mentioned in TFA is very different from that. The material I worked with only derived energy from visible light - this material works in the IR bands, and I find that even more interesting as it's vastly under-explored. I'm not so sure about his "weaving it into fabrics" idea, but for sure it will help boost traditional solar cell (PV) gain.

Energy Payback.

Energy Payback.

Second, and far more fundamental, *it takes far more energy to make a solar cell than it can ever possibly collect*.

While this rumor has been circulating for a number of years, it is not even remotely true. Depending on what PV technology is used and specifics of geography and geometry, it takes anywhere from 6 months to about 8 years for a solar panel to produce the energy required to make it. This is very well established. The panels themselves have expected lifetimes of 20-30 years.

The cell degrades before it ever breaks even.

Not only does the cell not degrade before it produces the energy required to make it, it lasts so long that its lifetime is essentially unknown. Other materials in the PV module degrade, but as I said, expected module lifetimes are 20-30 years; in fact, manufacturer warranties are generally in the 20-25 year range.

Second, and far more fundamental, *it takes far more energy to make a solar cell than it can ever possibly collect*.

While this rumor has been circulating for a number of years, it is not even remotely true. Depending on what PV technology is used and specifics of geography and geometry, it takes anywhere from 6 months to about 8 years for a solar panel to produce the energy required to make it. This is very well established. The panels themselves have expected lifetimes of 20-30 years.

The cell degrades before it ever breaks even.

Not only does the cell not degrade before it produces the energy required to make it, it lasts so long that its lifetime is essentially unknown. Other materials in the PV module degrade, but as I said, expected module lifetimes are 20-30 years; in fact, manufacturer warranties are generally in the 20-25 year range.

Get your facts straight; Google all you want for other studies, but I like the one at
NREL.

There's about a dozen others saying about the same thing; energy payback within about 4 years, production lifetime of about 25. And no reputable study saying they don't make their energy back in their lifetime....

Almost. The taxes should be even higher, and we should fully fund national research labs like NREL. IMHO, alternative energy research is right at the top of the list that we should publicly find, right along with virus research.