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The Ugly Side of Solar Panels

Researchers are overly optimistic when they present the sustainability advantages of solar PV panels.

Image: Solar PV panels. Credit: Alseinau (CC BY-SA 4.0)
Image: Solar PV panels. Credit: Alseinau (CC BY-SA 4.0)
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Producing electricity from solar cells reduces air pollutants and greenhouse gases by about 90 percent in comparison to using conventional fossil fuel technologies, claims a study called “Emissions from Photovoltaic Life Cycles”, to be published this month in “Environmental Science & Technology”. Good news, it seems, until one reads the report itself. The researchers come up with a solid set of figures. However, they interpret them in a rather optimistic way. Some recalculations (skip this article if you get annoyed by numbers) produce striking conclusions.

Solar panels don’t come falling out of the sky – they have to be manufactured. Similar to computer chips, this is a dirty and energy-intensive process. First, raw materials have to be mined: quartz sand for silicon cells, metal ore for thin film cells. Next, these materials have to be treated, following different steps (in the case of silicon cells these are purification, crystallization and wafering). Finally, these upgraded materials have to be manufactured into solar cells, and assembled into modules. All these processes produce air pollution and heavy metal emissions, and they consume energy - which brings about more air pollution, heavy metal emissions and also greenhouse gases.

Energy mix

The ecological burden of energy use depends on the way electricity was generated. Therefore, the researchers bring into account 3 scenarios. One is based on the average European energy mix, another on the average American energy mix (which is about 45% more CO2-intensive). (Note: in this article, “CO2” stands for CO2-equivalents which means other greenhouse gases are included). A third scenario uses the figures of the recent “CrystalClear” European Commission project, which investigated the real energy mix used by 11 European and American silicon and PV module manufacturing factories. Since they use comparatively more gas and hydropower, this is the best case scenario. The researchers investigated 4 types of solar cells: multi-crystalline silicon (with an efficiency of 13%), mono-crystalline silicon (14%), ribbon silicon (11.5%), and thin-film cadmium telluride (9%).

The optimistic conclusions of the researchers are based on a life expectancy of 30 years and solar insolation in the Mediterranean

The scientists come up with figures concerning the amount of greenhouses gasses emitted per kilowatt-hour of electricity delivered by one square meter of solar cells. They do that for every type of cell and for the three different scenarios. Thin film solar cells get the best score with 20.5 grams of CO2 in the European energy mix and 25 grams of CO2 in the American energy mix. In spite of their lower efficiency, they are more eco-friendly because they need less material and no aluminium frame. In spite of their high efficiency, mono-crystalline silicon cells score worst, with 43 grams of CO2 in the EU, and 55 gram of CO2-equivalent in the US. All other types and scenarios fit between these two extremes.

Solar insolation

However, these conclusions are dependent on some assumptions, most importantly solar insolation (the amount of sunlight that the cells receive) and lifetime expectancy. For solar insolation, the researchers choose 1,700 kWh per m² per year, which is the average of sunlight in Southern Europe. For lifetime expectancy, they choose 30 years. From these variables, they calculate the total lifetime electricity generation of one square meter of solar cells. Next, they divide the amount of CO2 emitted for the production of one square meter of solar panels by this lifetime electricity generation – and that’s how they achieve their conclusions.

Surprisingly, the key data of the calculation (the amount of CO2 emitted per square meter of solar panels) are nowhere to found in the report

Surprisingly, the key data of the calculation (the amount of CO2 emitted per square meter of solar panels) are nowhere to found in the report. That’s remarkable, since these data are the most objective numbers available. Even so, they can be calculated by multiplying the obtained results (in gram CO2 emitted per kilowatt-hour of generated electricity) by the lifetime electricity generation. This calculation gives the amount of greenhouse gases emitted for the production of one square meter of solar panels, regardless of the assumptions on solar insolation and lifetime expectancy.

2 to 20 flights

Once calculated, it’s not so suprising that the researchers choose not to write these figures down. In the best case scenario, one square meter of solar cells carries a burden of 75 kilograms of CO2. In the worst case scenario, that becomes 314 kilograms of CO2. With a solar insolation of 1,700 kWh/m²/yr an average household needs 8 to 10 square meters of solar panels, with a solar insolation of 900 kWh/m²/yr this becomes 16 to 20 square meters. Which means that the total CO2 debt of a solar installation is 600 to 3,140 kilograms of CO2 in sunny places, and 1,200 to 6,280 kilograms of CO2 in less sunny regions. These numbers equate to 2 to 20 flights Brussels-Lissabon (up and down, per passenger) - source CO2 emissions Boeing 747.

According to the researchers, producing the same amount of electricity by fossil fuel generates at least 10 times as much greenhouse gasses. Checking different sources, this claim is confirmed: 1 kilowatt-hour of electricity generated by fossil fuels indeed emits 10 times as much CO2 (around 450 grams of CO2 per kWh for gas and 850 for coal). Solar panels might be far from an ideal solution, but they are definitely a better choice compared to electricity generated by fossil fuels. At least if we follow the assumptions chosen by the researchers.

Northward

Logically, if we make the same calculations for a solar insolation of 900 kWh/m² (the yearly average in Western Europe and in the Northeast and Northwest USA), the results get worse. In the worst case scenario (US grid, mono-crystalline silicon), emissions rise to 104 gram CO2 per kilowatt-hour of solar generated electricity, which makes solar panels not 10 but only 4 times cleaner than gas.

If we combine this lower solar insolation with an expected lifetime of only 15 years, the worst case scenario becomes 207 grams of CO2 per kilowatt-hour – just 2 times better than gas. Agreed, this is the worst case scenario, and even in that case solar panels are still a better choice than fossil fuels. But it becomes quite hard to describe them as a “clean” source of fuel.

Life expectancy

The life expectancy chosen by the researchers is, well, just an expectation. It’s true that most manufacturers give warranties of 20 to 25 years, so technologically speaking a life expectancy of 30 years is not implausible. However, there are other than technological reasons that may lead to a significantly lower life expectancy. The scientists note that the environmental score of solar panels will improve, because they are becoming more efficient each year. (They also become thinner, so less energy is needed to make them). Most likely they will also become cheaper.

That means that in 15 to 20 years time, if the evolution in efficiency carries on the way it does now, a solar panel with an efficiency of 10 percent produced today will have to compete with cheaper solar panels that have efficiencies of about 20 percent. Moreover, and that’s a fact that the researchers are not taking into account, solar cells degrade in time. Typically, the warranty given by solar cell manufacturers covers just 80 percent of power output. All this means that it may make sense to substitute older panels with newer panels before they are 30 years old. Again, even in that case the ecological score will probably still be better than the one of fossil fuels, but the point is that the gap can become small.

Gadgets

For rooftop and ground-base installations, the eco-friendliness can be good or doubtful, depending on the solar insolation and the life expectancy. But if we consider solar panels mounted on gadgets like laptops or mobile phones, solar energy becomes a plainly bad idea. If we take a life expectancy of 3 years (already quite optimistic for most gadgets) and a solar insolation of 900 kWh/m² (quite optimistic too, since these things are not lying on a roof), the result is 1,038 gram CO2 per kWh in the worst case scenario (high-efficient mono-crystalline cells produced in the US). That means that it is better for the environment to power a gadget with electricity generated by coal, rather than by a solar panel.

Furthermore, none of these calculations takes into account the embodied energy and emissions of the energy storage, which is much larger still.

Now what?

All this does not mean that PV solar energy should not be promoted. For one thing, it’s much better using silicon wafers to make energy generating equipment instead of energy guzzling equipment (like computers, mobile phones and car electronics. But some facts have to be faced.

First, solar cells are far from a zero emission technology. Two: solar panels can be a doubtful choice in less sunny regions. Three: solar panels mounted on gadgets are completely insane. Four: solar cells should be recycled. Five: some law or incentive should be introduced to guarantee a life expectancy of 30 years. And if possible, solar thermal power should have priority over solar PV power, because it depends on technology that is less energy intensive to produce.

A better strategy would be to use already available solar panels to produce more solar panels

It should be realized that solar panels first raise the amount of greenhouse gasses before they help lowering them. If the world would embark on a giant deployment of solar energy, the first result would be massive amounts of extra greenhouse gasses, due to the production of the cells.

A better strategy would be to use already available solar panels to produce more solar panels. The scientists calculated that the ecological burden of solar panels can be halved if 100 percent of energy in the factories would be delivered by solar energy.

I did not do the calculations for air pollution and heavy metals, but since these are mainly produced by energy use for production, the conclusions must be similar.

Updates

Solar photovoltaic (PV) systems and their manufacturing become more efficient over time, so you would expect that the situation has improved since 2008. However, things got worse. This is largely due to the relocation of manufacturing to China, where the electric grid is twice as carbon-intensive and 50% less energy efficient. Relocation can also lead to positive results. If we would produce solar panels in countries with low carbon grids, and install them in countries with high solar insolation and carbon-intensive grids, the potential of solar panels would be huge. We have to rethink the way we use and produce solar energy systems on a global scale. Read more: How sustainable is PV solar power? (April 2015).

In today’s solar photovoltaic systems, direct current power coming from solar panels is converted to alternating current power, making it compatible with a building’s electrical distribution. Because many modern devices operate internally on direct current (DC), alternating current (AC) electricity is then converted back to DC electricity by the adapter of each device. This double energy conversion, which generates up to 30% of energy losses, can be eliminated if the building’s electrical distribution is converted to DC. Directly coupling DC power sources with DC loads can result in a significantly cheaper and more sustainable solar system. However, some important conditions need to be met in order to achieve this goal. Read more: Slow Electricity: The Return of DC Power? (April 2016).

The typical solar PV power installation requires lots of energy to produce it, access to a private roof, and a big budget. However, wouldn’t it be possible to get around these obstacles by installing small solar panels on window sills and balconies, connected to a low-voltage direct current (DC) distribution network? To put this theory to the test, I decided to power Low-tech Magazine’s home office in Spain with solar energy, and write my articles off the grid. Read more: How to Get Your Apartment Off the Grid (May 2016)

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JuandeSant

Very interesting article indeed… Even when “The ugly side of solar panels” is maybe a little extreme, it is true that the carbon footprint of manufacturing any piece of technology cannot be neglected.

Maybe I’ve skipped over some section, because even when I think I understand the logic for no solar panels in gadgets (low efficiency of small panels, while manufacturing cost increases per square cm), maybe it should be more explicitly expressed.

Kris De Decker

@ Dana Curtis (#96)

Everyone is welcome to read Low-tech Magazine. If I’m preaching outside my church, all the better. If they use my article to support their views, they will have to refer to it, and if they refer to it, their supporters will be confronted with facts and opinions that will surprise them.

Martin Cleaver

That’s not the only “ugly side” so solar panels. I am a great believer in the benefits of solar energy and other alternatives to oil, but a recent journey through Southern Germany made me think. Many picturesque old villages around the Bodensee are now defaced by huge shiney dark-blue panels. Whole farmhouses have been hidden behind them. Surely someone could pay a little attention to the aestetics of things. Just because it’s “Good for the Earth” doesn’t excuse “Bad Taste”. Please will someone look into alternatives? Say - slate grey, terracotta bronze?

Just plastering our world full of ugly blue sheets is not the answer. :(

Martin

Frank Schanzenbächer

“Style remains a matter of taste”. I am German, and I know the are around Bodensee. Its one of the most beautiful places in Germany. I do not see the solar panels as an disadvantage, in terms of messing up the scenery. I rather see it as an advance in time. Want to have some wood/clay/tarsheet tiles to absorb or reflect the light, or to use it wisely to regain the energy? Mr. Cleaver, its your brain playing a trick on you. What you consider nice, might appear dirty to others. Apart from that, there are other type of solar panels coming up. Translucent ones as brown/red and black are available. Only a matter of time.

The article seems quite one sided. Comparing the “worst case solar scenario” (old panels, bad location, little use) to best case gas. And still points out that it would only be twice as little CO2. Trying to write good things to be bad. Imagine a car would produce 50g of CO2 instead of 100g, by giving the same distance and power of engine… It would be a breaker…

Soren

Before jumping to the conclusion that gadgets should be “powered by electricity from coal,” I think one needs to examine the CO2 costs of the *batteries* almost all gadgets use to store power. And the often-inefficient transformers that are used to charge those batteries. For a desktop calculator, at least, the PV modules are often *in place* of batteries. If other devices can have smaller batteries by adding solar panels for more frequent recharging, the CO2 cost might go down … probably not enough to pay itself back in the three-year lifespan of the device, but perhaps bringing it out of the “insane” level.

Maybe most gadgets with PV have the same size batteries as if they had no PV, but to assume that you can attach a coal plant directly to your cellphone (or even to a land line telephone, which has lots of batteries at the telco) seems like jumping to conclusions too quickly.

I don’t have PV on my house yet … first has been a reduction to 60 kWh/mo of electricity, now is installing a 1.6 GPM shower head, and next will be a solar thermal collector to heat the house and water (I still consume at least 10 therms of gas each month in the cooler months).

Joe

Its great to see both sides of an arguement. I generally agree with the conclusions, but I think we should consider the longer term future and not focus so much on current limitations of what is still a relatively immature technology.

As with any new technology, PV will become more efficient, cheaper and cleaner to produce. In order for this to happen we (Governments / NGOs / Individuals) need to invest more time and money into making PV viable, e.g. through regulations, technical standards, R&D, manufacturing processes and generating consumer demand.

As more electricity is generated from PV (and other renewable sources), the manufacturing of such technology will become less carbon-intensive.

In terms of using PV for gadgets, I agree its difficult to justify over such a short life expactancy. However, this will change as manufacturing costs / carbon emissions decrease and efficiencies increase. I do have a problem with the manufacturers of these gadgets as they intentionally design their products to last such short periods - this is where regulations should be put in place for increasing life expectacy and making the manufacturers responsible for the disposal of ‘old’ products.

david_42

Having followed the solar industry for over 40 years, I’ll make a few observations. First, solar thermal for large installations is 2-3 times as efficient as photovoltaics AND uses far less materials. It is also very easy to build energy storage into thermal systems. Second, there is a class of gadgets where photovoltaics is just about perfect. Those are remote sensing and sparsely populated operations. The solar panel/cell phone/gell battery kiosk for emergancy phones is a good example of the latter. Installing them along I5 in California cost 1/4 as much as a wired system and that included building the cell towers and relays.

In the middle ground, powering homes and businesses, the cost effectiveness of solar depends strongly on the ability to push excess power back into the grid. Home power loads are seriously out of sync with supply. My peak loads are at night in mid-winter. At noon in the summer, I need almost nothing.

A concerned Reader

http://pubs.acs.org/cgi-bin/sample.cgi/esthag/asap/html/es071763q.html

“… Overall, all PV technologies generate far less life-cycle air emissions per GWh than conventional fossil-fuel-based electricity generation technologies. At least 89% of air emissions associated with electricity generation could be prevented if electricity from photovoltaics displaces electricity from the grid.”

Andy Simpson

I think that you should check your calculations. They looked a bit suspect to me because the amount of energy used to make the panels would cost more than the wholesale price of panels. So I checked:

Looking at the best case scenario, you say that a square metre of solar panel will cause 7,527 kg of emissions, given an emission intensity of 20.5 g/Kwh. That implies that the panel generates 7,527/0.0205 Kwh over its 30 year life time (the 30 years comes from the study).

7,527/0.0205 Kwh = 367,170 over 30 years.

That’s 367,170/30 = 12,239 Kwh/ year - not bad, but sadly not possible given a solar intensity of 1700 Kwh/year.

jim

Rushing through the article, I reflect on the idea that solar cells might become dramatically cheaper to produce in a few decades due to materials research and production technologies. Solar cells tend to diminish output over time, but still can be productive with a fractional output. They might be useful for hundreds of years if sufficient real-estate exists to recycle them as low-yield units where possible. Design technologies already exist that greatly extend the output of cells, by external focusing of sunlight on cells and the use of susbstrate cooling systems. I remember a member of my computer club some thirty years ago who went on to wealth and fame in part for his self-focusing cell systems that achieved a record for output for given parameters (Midway Labs, 1980’s). Unfortunately, Paul Collard did not fully appreciate the importance of cooling systems to preempt premature aging and his systems succumbed to declining output in only a year or two. However, new experimental systems are promising. Don’t write them off completely. You might be disappointed.

Lots of research:

http://www.redrok.com/main.htm

Ron Swenson

Would I trust any conclusions drawn by someone who blithely makes a mistake of 2 orders of magnitude? (That said, I do appreciate that you fessed up!)

I would prefer to resort to the conclusion of the folks who wrote the original article on which this opinion piece is based:

“At least 89% of air emissions associated with electricity generation could be prevented if electricity from photovoltaics displaces electricity from the grid.” See http://pubs.acs.org/cgi-bin/abstract.cgi/esthag/asap/abs/es071763q.html

BCL

Actually, having worked in the semiconductor industry, I was happy to see somebody perform this analysis. I always wondered if the energy going into producing those solar panals was more than what came out. I was actually worried that they might take more energy to make them than they produce! Fortunately this turned out not to be the case but there are other concerns. Manufacturing of the panels does use huge amounts of water (this depends on the specific process used to make the panels, but it could be as high as a 1000 gallons per sq. ft. Also, there are a host of toxic chemicals used in the proces as well which might make solar less attractive. Of couse, non VC based systems are much better over all.

Vasilis Fthenakis

Kris De Decker exhibits great ignorance about PV technology and life cycle impacts with his comments. The study in ES&T that he cites, undertook year-long independent expert peer reviews before it was accepted for publication by this most prestigious journal. Just a couple of remarks to some of his points that deserve an answer. Degradation losses of 0.5% to 1% /yr are included in our studies; the low number is confirmed by utility (e.g., TEP, AZ) records and the utility posts on the web daily perfomance of their biggest plant Springerville). The numbers of gCO2/kWh that De Decker (is this a real name?) demonizes us for not showing!! are intermiadiate numbers in a LCA. The final numbers with which PV can be compared with nuclear and fossil are g CO2/kWh. The former can easily be backcalculated from the later.

His assumptions about 3 yr life expectancies are rediculous. PV flat modules have confirmed lifes of 30 yrs and their structures can well last 60 yrs, but consevatively, we used 30 yrs for both.

Dr. Vasilis Fthenakis

Brookhaven National Lab and Columbia University

DC Power Systems

you must be paid by the Oil industry.

you are spreading lies.

Jay Draiman

Renewable Energy Manufactures/suppliers should use their own product to manufacture.

The manufacturers’ of Solar Panels and other forms of renewable energy with related support products manufactures/suppliers - should have at least the decency to practice what they preach what they market to the public.

That would be the best marketing approach I can think off.

If they believe in the product, they should utilize it to its fullest potential.

It will give the manufacturer the actual experience of utilizing the product on a daily basis, view and experience any improvements that are needed, implement the improvements and capitalize on that improvement to improve the product and its performance.

This will instill confidence in the public to purchase the product.

Jay Draiman, Energy Analyst

Jerry

While this article has some valid points, its arguments are now obsolete. Using a new nanotechology based ink, NanoSolar corporation is producing 100’s of feet of solar panel per minute. No foundries, no highly toxic metals. No need for huge amounts of energy consumption (CO2) like with crystalline silicon cells. The new ink based panels cost a tiny fraction of silicon. This technology is going to change the world as we know it.

I’ve built solar panels by hand and while I can’t vouch for the numbers in this article, there are most certainly environmental negatives that come with using silicon cells. I was poisoned when I handled silicon cells without gloves and I’m still dealing with the effects of that experience.

Eric H

Great article, glad to see it, don’t let the DAs get you down. I too am an enthusiast for sustainability who is critical of thoughtless cheerleading. Photovoltaics are, unfortunately, a sexy but less-than-perfect answer, as is wind. There are those who like to see the world in a black-and-white, us-vs-them, all-or-nothing mindset, be it for their favorite political candidate, their environmental cause do jour, or their energy solution.

Having just visited Germany, I can tell you that things are worse than you make out here. I don’t agree with Martin that the blue panels deface (I think they’re kind of cool looking against the traditional reds and browns), but I did see lots of people planting them on their ultra-steep roofs (much more than the latitude) and pointing them in whatever direction the house seemed to face on the street side (north, east, south, whatever). I think the goal was to impress the neighbors rather than to generate energy, and why not? The government is paying for it! I asked a friend if he knew how many cloudless days they got - it happened to be overcast with high clouds at the time and he (only partly in jest) said, “You mean sunny like this? Because this is as close as it gets.”

pewp

I’ll take the ugly side of solar over the ugly side of nuclear and oil any day.

kris de decker

Author here. Can’t believe that this topic is still so controversial, 12 years after the article was published.

I am still standing behind this article, and if you read the update article from 2015, you see that this original post was not critical enough: we now produce solar panels in China, which increases their CO2-footprint and energy use, and we install them mostly in regions with not much sun, which decreases their energy production.

Finally, I am not against solar panels. In fact, both my office and my new website (https://solar.lowtechmagazine.com) run on solar power. Solar PV power is not a black and white issue. We should discuss both the good and the bad or ugly sides.

Amber Fergason

Fascinating argument back and forth for a lay person such as myself. I was simply googling for manufacturing articles for solar as a prospective business to get into. Wow! What a summation of information. Thanks for sharing.

Hans Jergenofski

I would suggest we give a good long studied look into the energy production values of how a magnetic spinning disc could generate energy uinto a generator similar to the ones that wind turbines are generating but with higher friction values for higher electric output from the powerful spin that can be caused by rare earth magnets in specific allignments

Captain Obvious

what the HELL is with the bizarre assumption that heating silicon to 1800F ( whatever /that/ is, in Centigrade :) need be done with “nucular” or fossil fuels??

USE A SOLAR CONCENTRATOR.

Dear Bloody Kripes, people: Cheap, Available, and Effective.

WHERE does all that eco-cost come from??

Assumptions?

davea0511

Actually the very first resource I supplied, the one that was a doctoral thesis, was a study done on the insolation in Ohio, a very non-optimal solar situation. A far more aggressive analysis then your back-of-napkin thing. What motive would he have to paint a rosier-than-reality picture … especially when it’s going to get torn apart by his professors? If you’ve spent time in academia as I have you’d know he’d be stupid to do so. And it comes out with a CO2 payback of 3.7yrs, and 7 for total energy. The Swiss study is jsut as objective, showing that in China where they throw environmental caution to the wind it may never environmentally pay for itself, but clearly show how it can be brought down (and will be - for economic reasons) to 4 yrs. Of course,

But the idea that any one of the references I gave you feel in flawed invalidates all the other references simply doesn’t follow reason. These are independent analysis done from widely different perspectives, backgrounds, and motivations.

I think you’re on the right track with leveraging low-tech whenever it is superior, but you fail to realize that solar energy is really very low-tech … it’s just a big diode - the simplest electrical device in the world.

But turning the goo in the ground into gasoline with all it’s high-tech additives, the dealing with all the waste and turning it into useful stuff through tons of processing with sulfur and all it’s CO2 heavy logistics … that my friend is a lot more complicated, and you suggest it’s better than building a diode that spits out energy for 25+ years or more? Well, it’s your website so I’m not going to insult, but your positions speak for themselves, whether they’re good science are absurd.

Sam F.

Thanks for the calculations and the back-and-forth dialog. (I especially like the hypocrisy of the guy from DC Power Systems anonymously saying you must be a shill for Big Oil).

One question that was asked below and wasn’t answered:

You say that PVs on gadgets is insane because the energy used to create the PVs is more than the total energy produced over the lifetime of the product. But this is only half the story, because gadgets without PVs require more batteries to be manufactured and more energy to fill those batteries.

(PS: Same bug with posting is happening. I’m on FF after having been on this page for a long time. I’m now refreshing and trying to post quickly.)

The question isn’t whether the PVs will produce more energy than was used to create them, but whether, all things considered, a gadget with PVs consumes less energy than a gadget without.

Do you have any figure for the energy that goes into a gadget with a three-year lifetime, consuming multiple batteries, each of which has to be made and charged?

anyone

Of course it matters, whether you build a new coal power plant and a new coal mine and burn lots of coal or whether you build new PV modules and do not burn coal at all.

And your solar battery combination dream will never happen, because batteries are simply too expensive and not needed anyway, because PV will reduce the load on the current grid.

Again, fact is that thinfilm PV modules do not use energy intensive manufacturing methods and if one produces lots of them, the fossil fuel portion in the electricity grid will obviously be reduced, because most people actually install PV modules on roofs to produce electricity and not in their basements for fun.

Fact is, the more PV modules are built, the less CO2 is produced during the production of future PV modules.

ganv

Sounds to me like the researchers you are critical of had a more objective spin on the data than you have. Your map clearly shows that southern Europe is typical of most of the US land area. And your final paragraph upends your entire argument. The solution is to get on solar and other renewable energy sources as soon as possible so that we can build the rest of our renewable energy system using low carbon energy sources. An honest calculation would compare the CO2 emitted by waiting to go to renewables with the CO2 emmitted by going to them as soon as possible. In the next century we have to go to renewables, and there is not enough energy to go to renewables without relying heavily on solar. The only question is when. And there is just no ‘ugly’ side of solar energy when honestly compared with the other options. The only drawback is seen by the shortsighted who note that it costs now rather than deferring the costs to our grandkids.

canada eh

even though i have no idea who is winning, i love watching a nerd debate.

Zachary

What about if you try to store the solar energy? In Germany, the world leader in solar, they feed it back into the grid when they’re not using it, but they get only 1% of their power from solar. If everybody did that it wouldn’t work, since their is no power at night and little in the winter, evening, morning, and when it’s cloudy. You’ve got to store it, and the cheapest way to do that is lead-acid storage batteries. A single gallon of gasoline contains as much energy as one ton of lead-acid storage batteries! In other words, to make the batteries would take a huge amount of energy, and storage would lower the efficiency of the use of the energy. In other words, solar would probably have something like five or ten times the carbon footprint, making it perhaps comparable to coal-fired power, at about 100 times the cost. What a joke.

Marcos Tanaka

Hello,

Interesting analysis. It is reasonable to try to see the complete scenario. Though, I was wondering if you took into account the energy needed to produce turbines, generators, furnaces, water and steam pipes, valves… but again you would need to take into account the energy required for a facility producing solar panels.

Moreover, there is energy loss involved in transporting electric energy… Having the energy produced into your own home would definitely be more efficient as regards energy transportation.

Best regards

BB

This is not a black and white issue but I do have to say that no solution will be perfect until we reduce our energy consumption and find more efficient technologies. Not an easy task but this has to happen first.

Lee Streisfeld-Leitner

The article seriously over-states the amount of energy embodied in solar panels. A polycrystalline panel, over an expected 30-year lifespan, will produce 10-20x the amount of energy that goes into its production (starting with the mining of the raw silicon dioxide for the cells and the bauxite for the frames, through the final assembly and distribution). That the author is using innacurate information can be easily demonstrated by looking at the economics: a typical 200W polycrystalline panel mounted facing south at about a 30-degree pitch in, say, Pennsylvania, will produce about 220 kWh per year or about 5,500 kWh over a 25-year lifespan (most panels are expected to last over 30 years). At an average electric cost in the US of about 10 cents/kWh, that’s $550-worth of electricity. That 200W panel will sell wholesale for about $450. The total cost of that panel to the manufacturer is probably no more than $350-400. To manufacture and market that PV panel the manufacturer had R&D costs, amortized costs to build manufacturing plants, O&M costs, costs of materials, insurance, labor/salaries, taxes, sales & marketing, shipping, etc., etc. Clearly, given all of those costs, it’s obvious that the embodied energy is not going to be that significant. Even if $50 of the $350-400 represents embodied energy (which seems high), that still suggests the panel will produce 10x that over its lifetime (and, by extension, offset approximately 10x its embedded carbon).

Piyush

PV technology and some other renewable technologies have been colored heavily with fossil energy and non-renewable non-recyclable materials so there is a big potential for enron like accounting and I am glad that articles like these are stimulating the minds of those who are sold on solar tech to search the truth. Solar breeder plants (using solar to produce solar materials) have been rare and are still not a closed system. Solar tech as it presently is looks unsustainable.

Yes there is plenty of energy from sun, but it is spread out in comparison to what nature did in concentrating a lot of this over millions of years to create fossil-fuels. The game from fossil fuels to solar is about integrating sunlight over reasonably large areas and large time to a large area and smaller time, the large area challenges us in terms of the gear for capturing and concentrating light (which is minimal for fossil, it is essentially just drilling a hole and getting out nearly ready to use high density energy) and the small time challenges us in terms of storage technologies, which in turn require energy, thus lowering the net return on energy (if at all positive).

The solar technologies that are more likely to be sustainable are biology based or solar thermal. A lot of research and lab work should be done to find real answers on net energy and sustainability of solar tech before deploying on a large scale, otherwise it will be sunk investment in comparison of more impactful solutions like conservation and curtailment and lifestyle changes.

Adam

#53, your 200W panel will produce only 300kWh power, or $30 worth of electricity over 25 years.

0.2kWh * 25% (max theoretical load) * 70% (max insolation, little clouds) * 365 days * 25 years = 320kWh

Also, large energy consumers like chip manufacturers and solar panel manufactures, buy electricity at bulk prices. Their effective cost is closer to $0.04-0.06/kWh, depending on jurisdiction (some are cheaper, even down to 3c/kWh).

Glenncz

No one here is looking at this the right way. Let’s keep all the scientists and the FANCY bogus studies out of it!!!

www.nofreewind.com for numbers.

It’s now 2011 and a 3MW solar plant is going up near my house in Pennsylvania at a cost of 18 million dollars. At about 13% output here in the NE it will produce 3.4 million kWhrs per year. If we take a loan at 6% on the 18 million dollars for 25 years it will cost 42 cents per kWh.

Also, I have a proposal for an industrial rooftop installation in front of me. It is rated at 182kW’s at a cost of 1.2 million dollars. Take a loan at 6% for 25 yrs and the cost per kWhr is 48 cents. That is all wholesale w/o hookup costs nor maintenance. Also the larger installation does not take into effect new transmission lines.

That’s all wholesale. We know a grid can buy coal at 5 cents per kWhr and nat gas for a little more, maybe 8 cents per kWhr. Those numbers include both capital costs to build the power plant and fuel costs. Solar is at least 6 times more expensive. What needs to be considered is how much of that 42 or 48 cents per kWhr is spent on “energy” and how much on labor. This is simply an impossible calculation, you would need to consider gasoline costs for workers to get to their manufacturing/mining sites, transportation costs, sales and marketing(there is lots of that!) and even extraneous costs like what NGO’s and Gov’t agencies spend to market this VERY expensive electricity which makes people (foolishly) think this is something they would want. o

Energy spent per GDP is 8-10%, so we would have to think the energy used to create these panels could be 5 cents per kWhr.

Now of course that assumes interest rate of 6%, cost drops in half with no interest to around 22 cents per kWhr. So maybe?? energy used is only about 2 cents per kWhr. But don’t forget to factor in all those IPCC conferences and thousands and thousands of global warming papers, and billions of dollars spent worldwide on this whole subject of global warming and alternative energy.

Nope, solar doesn’t pay whatsoever, not by any standard!

Xander

You guys comparing Solar PV to coal, Natural Gas and other fossil fuels are seriously underestimating the value of Solar PVs. You can’t compare Solar to coal or Natural gas based upon the cost per KWH because Solar has a unique property that neither of those energy sources have.. You can install solar panels just about anywhere and they produce the most electricity during peak hours. Electricity is not just $0.12, $0.08 kwh like you think it is. To a utility company, electricity produced during the day has a far greater value than electricity produced late at night on a weekend. You would see the true cost of electricity if everyone was put on time of use since that more accurately reflects the cost to the utility. It’s not easy to add capacity especially capacity that is only needed during peak hours since it will be completely unused during non peak hours. Coal and Natural gas also cause global warming which a lot of people seem to be glossing over. PV panels made today have an energy payback period of about 18 months now so the point about panels using about the same amount of energy to make as they produce is no longer true. Finally, the point about panels efficiency being low is only partially true.. The article implies the highest efficiency economically viable panels have an efficiency of only 14%.. That’s not true as there are economically viable panels that are now being sold with efficiencies as high as 22% now, therefore decreasing the time it takes for the panels to pay for themselves.

Mantion

I agree with 57..

Another way to look at is is cost come down when production goes up. Everyone complains that more people need to buy and use solar panels so that cost of production will be reduced.

I remember reading over a year ago that a thin film solar cell company was actually going to power its operations with thin film solar cells.

I found this to be very interesting. The assembly plant was never built. Raise your hand if you have actually been to a PV assembly plant.. hmm I only see my hand.. Ok, keep your hand up if they actually used the product they are making to generate electricity for their assembly plant.. huh my hand went down. I don’t know of a single assembly plant that powers their operations with PV cells.

Surely if the company X over produced and used their cells to generate electricity they would be able to lower the cost of production and become more competitive or at the very least have a marketing ploy and say “we like the product so much we use them”.

I have seen grocery stores with solar cells, office buildings, schools and colleges… I don’t know a single assembly plant to use its on cells. I work on computers, when they break I fix them.. I did IT for a fast food company, when I was hungry I ate the food there. When I worked for a news paper, I actually read the news paper.. When I work for a ski resort, i skied their mountains.

I think it is telling that assembly plants don’t practice what they are selling. If you walked into a resturant and asked an waitress what she liked, and she said “oh I don’t eat this crap” would you… Now as I said I might be wrong, if you live near an assembly plant feel free to stop by and see if they actually have PV cells generating electricity, and I don’t mean one or 2 as a display.. I mean a significant number that offset their energy usage.

That said I am only asking about assembly plants, i am not talking about all the mining and refining stages, god only knows they would never power their operations with PV.

I would love to think there is at least one assembly plant that actually uses PV power…

Tom Y

Embodied carbon is a huge issue. Your calculations saying that in the worst-case scenario solar panels have half the carbon footprint of gas, for example, no doubt doesn’t include the carbon footprint of extracting the gas, building and operating the gas power station and transmitting the energy.

Embodied carbon is massive and must be taken into account, but to use it as an argument against renewable tech is ludicrous - examine the embodied carbon of non-renewables alongside it.

Your attention-seeking title distracts from the valid point of this article: we need to ensure solar panels in tech gadgets are recycled well and not put in as ‘greenwash’ marketing only.

Turboblocke

#56 your calculation is wrong: the 25% efficiency is already included in the rated capacity and you’ve ignored the hours per day of operation.

It should be 0.2kW x 12 hours/day(average over a full year)x 365 days x 25 years. = 31,900 KWh. You might want to include a reduction in efficiency due to really cloudy days, but many cells work under overcast conditions.

sam

Forgive me if these comments were made previously, I didn’t have time to read them all.

You state that the CO2 cost of harvesting and producing the solar panels is not listed, yet you don’t consider the cost of harvesting, processing, and transporting the fossil fuels we use, which I would believe is more than silicon (but can’t be sure).

A point I would also like to make is that organic solar cells would can be produced in a lab, and use no silicon. These types of solar panels while currently less efficient than their solar counterparts offer great potential in their low cost and means of production. However research into these products is discussed little in the media, and receives very little funding.

xtian

No one seems to put in the cost of the batteries and dc/ac converters and the costs to manufacture these. Like the Prius, you could run old Land Rovers for years to make up for what it takes to make one.

CO2 is not a poison or a problem, we would die without it. It is plant food

neutrino78x

So, we read this whole article, only to find that in the author’s worst case scenario, solar panels are still twice as clean as a coal plant!!!!!!! So, how is that “the ugly side of solar panels”???

Secondly, yes, of course the goal is for all industrial processes to use green tech. So it is not a case of “a better scenario would be for the processes used to make the panels to also be green”, because that is already the goal in using solar power.

Over time, solar power gets cleaner and cleaner, whereas fossil fuel generation continues to emit more pollution!!!!

An interesting article, and I love this web site…but I disagree with the point being made in the article.

Sick of CO2

Good grief, all these comments. This whole CO2 thing has gone way past the point of insanity.

Here’s a consensus for ya:

“The Nazis enlisted other physicists, including Nobel laureates Philipp Lenard and Johannes Stark, to denounce Einstein. One Hundred Authors Against Einstein was published in 1931.

When asked to comment on this denunciation of relativity by so many scientists, Einstein replied that to defeat relativity one did not need the word of 100 scientists, just one fact.”

~ Encyclopedia Britannica

Nice article, btw. Found the information I was looking for. Thanks!

BadMathWillDestroyTheWorld

The math in the article is flawed.

If 1 square meter of solar panels carries “at worst” a burden of 314 kg of CO2 from its manufacturing process and produces “at worst” 900kwh of electricity, that is 348 grams of CO2 per kWh. But what the author conveniently forgets to remind us is that the 314kg is the TOTAL CO2 attributed to the 1 sq-m of panel over its 30 year lifespan. It doesn’t produce 900kWh total. It produces 900kWh annually. So over 30 years, 348g of CO2 becomes 11.6 grams of CO2 per kWh. It’s easy to skew the facts against solar panels when you forget to ANNUALIZE the 314 kg from their manufacture.

I’m all for the right solutions to the problem. But we won’t find the right solution if people don’t do their math properly.

Tonmoy

Thanks for your response Kris.

Christian Sweningsen

Thanks for digging this up, for the analysis, and for the exchange of comments.

Regarding thin-film lifetimes and warranties: The fact of a warranty is very far from proof of lifetime.

That of course is a simple matter of logic. Worse, my impression is that manufacturers will give the warranty needed to sell the product. The company is unlikely to be around in 10 years, let alone 30. The pattern in management today is based on getting loans to get them jobs and stock. All they need to do is drive up stock value, cash in and get out.

Cathy Bell

Amen, Christian Sweningsen. Both the original author and commenters operate from the assumption that if the items are warrantied for 20 to 25 years, then they must have a 30 year life expectancy. That is naive and absurd. How many home users will monitor panel output for more than ten years, remember where they purchased the panels, be able to locate the manufacturer, still be able to locate their purchase receipt, and be willing to go through the hassle of requesting a refund? The marketing value of a long warranty far exceeds any possible cost of honoring such a warranty. I can’t find any independent study that comes anywhere close to those numbers. If you know of one, I’d love to see the link.

I’d also quibble with the argument that those in an industry are always biased and those in academia are always objective. Lots of university professors are bought and paid for by industry.

Stephan Dekker

I love the concept of this article, it addresses my think spot on. Good thing it’s still in favour of getting panels!

Although I would also be interested in the carbon emissions in retiring the panels after 30 years and what we do with the waste?

As a last thought: I don’t think I will live in my current house for another 30 years, so I would be buying them to increase the value of the house as well. From a fincancial aspect, I really don’t care whether they last for 20 or 30 years. So if the manufacturers and we (ok… I …) the consumers don’t care, I think we are in deep problems!

I’m not too naive to think that solar panels will fix our energy problems. However, every dollar invested into this market will bring the solution a little bit closer.

Cheers all!

Maarten

This discussion is great fun to read during your lunchbreak

Betterways

But aren’t PVs a much better use for all that sand than hydrofracking?

I’ve been trying to find out for sure, but a couple quick google searches hasn’t confirmed this for me:

For fracking, I believe what they want is sand with very high silica content. And isn’t that exactly what we need for PVs?

Too bad our government doesn’t subsidize solar so that they can compete with the ultra-rich and powerful oil and gas for the resources.

Ernie Tilley

O yea i forgot to mention that the life expectancy of those tubes in a boiler be it gas/coal/trash only last at most 5 - 6 years.

tesla

this whole article is mooted by the fact that solar cell technology is still in the beginning stages of development. things will presumably change a lot.

what you don’t write about is the feedback loop. if you buy energy intensive solar cells today, you are making an investment in the revenue stream which supplies research and development for more efficient.

if people hadn’t bought lesser efficient combustion engines, there would not be the more efficient engines we see today.

Tonys

An interesting read, thanks for that Kris de Decker. Well done in how you deal with those comments from people who haven’t had the courtesy to read your article properly. It is informative and rightly reminds us to question conclusions put out by ‘researchers’. Thanks - I do appreciate the time you have taken to put this together.

Luke Warmwater

Carbon Footprint of modern solar panels is around 30g/kWhr.

Remember that every kWhr produced by solar displaces a kWhr produced by coal or gas.

That is a huge effect.

And also remember that if you install or support solar on your house or neighbourhood you will have a multiplier effect around the world. Ontario is installing panels, because German’s did, and Spanish before them. So feel really good about putting those ugly panels on your roof.

Hghi efficiency solar panels in the US can be purchase for as low $.65/W now. Or about $120 for a 250W panel. Silicon panels are cheaper than thin film. Much higher power.

The revolution has begun!

Bill

79 makes a great point. The article is an excellent attempt at determining what the CO2 production is of solar technology, however it does not seem to employ the same rigor in determining what the true CO 2 production of fossil fuels is. Perhaps, the calculation used below from the article include such a cradle to grave analysis, but it is unclear -

“According to the researchers, producing the same amount of electricity by fossil fuel generates at least 10 times as much greenhouse gasses. Checking different sources, this claim is confirmed: 1 kilowatt-hour of electricity generated by fossil fuels indeed emits 10 times as much CO2 (around 450 grams of CO2 per kWh for gas and 850 for coal)”.

Mr. DeDecker was such a cradle to grave analysis used in the above quote. If not the solar power analysis is unfairly biased against solar power.

VandD

They are not “your numbers”, yes, but they are obsolete and far from current reality.

Elizabeth

Interestingly enough, the guaranteed life expectancy of a solar cell is about twice as long as the article claims. The first solar panels that were created by Westinghouse in the 60s are still operating at >80% efficiency. Maybe obsolete isn’t the right word. I’d say the correct term is skewed, but I’ll give the author the benefit of having written this over 5 years ago.

Murray B

What is important is the non-subsidized payback period of the entire solar plant and not just the solar cells. Most installations require, solar panels, charge controllers, battery banks, and inverters to work. The actual long-term energy costs of the entire plant is what matters.

CraigM6

Oh and a few more things.

SOlar panels need BATTERIES which need energy and metals mining and recycling.

They need far more COPPER or ALUMINIUM to transmit power to the users and factories, since they are more widely distributed for the same power production as, say, a nat gas plant.

Further, installing a solar farm, is like CLEAR CUTTING a piece of land since ALL the natural vegetative ground cover ( except that which sprouts in the accumulated dirt on untended panels ) is starved to death in the shade of the panels. Ecologocically, it is utterly disruptive. And these plants would have acted as a carbon sink.

Finally, you have to include the carbon cost of maintaining the solar farm. It isnt zero to have wash the surface dirt off panels and clear away the weeds that are reaching for the light between rows of PV panels abd do electrical maintenance. IF batteries are used, then they have to be tended and tested.

Cezar

Regarding photovoltaics on gagetry.. My father has an hand-held scientific calculator with a tiny solar cell. The internal battery is gone yet it is both useable and used in daylight or under a bulb.

It is almost 20 years old, and will not need another one.

That tiny PV cell saved a lot of energy for new batteries or new handheld calculators.

For rechargeable ones, how many phones, tablets, laptops are thrown only because baterry became unuseable and a replacement is half as expensive as the laptop itself? If life of these gadgets is delayed with say 10% by having a PV cell that helps battery life, then it effectively saves 10% of all the energy embeded in making another laptop or phone.

It’s true that it’s hard to count these indirect savings, but it’s also unfair to discount them in the equation of how much energy actually saves a PV cell attached to a device.

Quantummist

Good article but was a bit short on the calculations as the Panels are not all that is required to consider the energy and byproducts from the production of the cells… You have to also include the CO2/energy budget for the steel for the mounts and batt racks, the copper for cables, Switch gear, inverters and Battery plants…. Once you add the Totality from mine to end of life and include the energy to clean and maintain the systems you are actually producing Far More CO2 and using Far more energy that you save with panels not to mention the nasty byproducts and materials that will find their way into landfills and the environment wen the systems are trashed out…

Richard

I think the following calculations also need to be taken into account:

  1. Besides solar insolation, dust, bird droppings, smog, all tend to reduce power consumption.

  2. Toxic waste from solar cell factories have to be shipped hundreds or thousands of kilometres away. The transport uses fossil fuels. This should be added to the carbon footprint of the solar cells.

  3. The cost of transportation to the place of installation and its greenhouse footprint has to be taken into account.

  4. The total installation cost of the solar panels has to be taken into account. I believe that this has not changed very much despite dramatic falls in the cost of the solar cells themselves, because the cost of the solar cells are but a small fraction of the total installation costs.

  5. The cost of batteries and inverters have to be taken into account, both in terms of money and environment.

In short Solar panels are ugly, but its a side that no environmentalist or media person wants to see.

Topher

“A better strategy would be to use already available solar panels to produce more solar panels”

Nope. Any solar panel connected to the grid improves the performance (in terms of CO2/kWh) of the whole grid, dedicating solar panels to making more solar panels is neither an improvement nor a detriment. It makes solar panel production look better, at the expense of making all other electric uses look (slightly) worse. What really matters is total CO2 into the atmosphere, and that is exactly the same.

Some ways to actually improve the performance include, installations with smaller amounts of infrastructure, installations which consume all the power locally, and installations in high sun areas.

Bruce

I saw an interesting point in SuperFeakonomics solar panels are black so while converting only a small proportion of photo energy to electricity the rest becomes heat that contributes to global warming.

Dana Curtis Kincaid

“I saw an interesting point in SuperFeakonomics solar panels are black so while converting only a small proportion of photo energy to electricity the rest becomes heat that contributes to global warming.”

Sigh… Doesn’t work like that. Are you actually saying that painting something black will generate heat? Oh goodness…

Well then, in the fall, let’s paint all houses and buildings in colder climes black. They’ll generate their own heat and won’t need furnaces.

George

Why would it make any difference if you are using solar energy to create solar panels and not just using it to power the grid in the most optimal locations? Seems like the only important factor to reduce CO2 is to put them where there is a higher density of solar energy.

My limited knowledge gives me the opinion it is a waste of the Earth’s resources to put solar pv systems in sub optimal places. Maybe there are factors that aren’t so obvious.

Lars

I think it’s time to update this article. THe solarscorecard.com group does an excellent job of tracking the industry performance. Some are already doing really wel

http://www.solarscorecard.com/2014/2014-scorecard.php

My blogpost on the subject:

http://larsboelen.nl/2014/11/an-inconvenient-truth-about-solar-panels/

Crashley

A 12kW triple junction GaAs solar array in space produces about 1.5 GWh in 15 years. How many Wh do you think it took to produce it? (I don’t know) Obviously it does not offset any terrestrial energy production since there is no other way to get power to the satellite

I realize this is not really relevant to the discussion, but I am curious.

By the way, the “scorecard” site did not seem to address how many Wh it takes to produce a W of solar panel output. Or maybe I missed it.

Jamey Johnston

Seem like there is a scholarly / engineering disagreement, hmm?

https://energy.stanford.edu/news/PV-industry-likely-net-energy-producer

pam

know-it-all rants by Devry tech grads like dana are really impressive…

Slowburn

Photo-voltaic is the wrong way to harvest solar energy. Use solar water heaters to drive absorption heat pumps, and Stirling cycle engines. Expand the ammonia through modified water cool ICE so that as well as generating the mechanical energy you get to keep the cool for food preservation, air-conditioning, & and water harvesting. This also give inherent energy storage as you do not release the anhydrous Ammonia to the engine until you need the power whether to directly drive a machinery or generate electricity.

Don’t forget to harvest the waste heat from the heat pump’s condenser.

Wouter Carrette

Did anyone even figure in the transportation CO2 footprint?

As most panels are produced in China, they still need to be moved to the rooftops in Europe/the US. How about that?

Peter

I think producing and using solar power systems, the positives far outweigh the negatives. Sure it will cost some to produce, but with the climate in such a fragile state as it is, ignoring the issue is not the answer. There seems to be so many misconceptions about solar, and you have to wonder where the rumours of this energy system get started, and whom it benefits in the long run? My bet is that for those who are invested in other energy systems would love to spread these negative issues around. Here is a helpful little article that I co-wrote about with an electrical contractor, that discuss the 7 top questions, and we were hoping to dispel the misconceptions in a casual way around solar power -

https://east-westelectric.com/the-top-7-questions-when-it-comes-to-solar-panels/

Abacus

Ok so we need to consider the amount of CO2 emission in total to produce 1 square meter of Solar Panel from scratch. Take that number to calculate the total CO2 cost over the life span of 20-30 years. Then compare that with the total amount of CO2 produced by Coal/Gas in the period of 20-30 years. WHERE do you account for the amount of CO2 cost to produce the entire infrastructure to support the entire Coal/Gas Industry ? It does not take a math genius to figure out what is wrong

ZMacZ

One more thing, when solar panels reach EOL, they can be harvested for the same materials that is required for the production of new cells. And that certainly generates a brand new re-use factor.

The breakdown of most solar cells is due to local high energy in the cells themselves, both from UV and electrons, causing electron migration. However, electron migration does not cause any chemical change, and only breaks down connections within the cells themselves.

Knowing that there’s only 2 substances in the degraded solar cells, they only need separating and ‘reformatting’ back into whole cells.

Ofc, there’s a price to it, and yet this is much lower than

production from raw materials. So, no, solar panels still better.

Burt Sidefish

hey Kriss, if you are still reading these comments

as I understand it, a big source of the emissions for silicon cells is in refining the silicon from silica, which oversimplified looks like this: SiO + C -> Si + CO2

which can’t be shunted with solar power, although the process is also energy intensive…which is why onsite solar probably isn’t common, needs a big and steady power supply that a solar based grid can supply but onsite cannot.

I have a dream of hydrogen refined silicon using a solar concentrator but I don’t know how I could achieve it, I being just some internet armchair warrior.

I hope we find a way to continue living.

Greg

OK, so somebody worked out the carbon footprint of producing the solar panels that generate electricity, and it’s still somewhere between marginally & much better than burning coal.

Now lets compare like-for-like: What’s the carbon footprint of constructing a coal power plant? (hint: there’s a lot of concrete in there). What’s the carbon footprint of building & running a coal mine? and trucking the coal to the power plant? PV solar still wins by a big margin.

Now lets get to the much more important question: Why are we still debating this?

Antonio Lambe

Thank you for a VERY topical article with many well-informed comments (and some quite misinformed and even boorish ones).

But the piece is >10-years-old and, as the author anticipated, the technology has since improved. Might an updated version be possible?

Martha Kennedy

Well it’s now 2020 and we just moved to Colorado. And solar is BIG BIG here. I’d just like to ask what are all these people going to do when the gas and oil run out??? Cause make no mistake it will. But hey guess that’ll be our kids problems huh? Along with land that has been gashed open to ha e it’s minerals ripped out causing deforestation, flash flood risks.Then toi can go into all the health conditions miners are prone too. As for my household we will be checking into solar soon

Kin Rocker

This is completely stupid.

“Next, they divide the amount of CO2 emitted for the production of one square meter of solar panels by this lifetime electricity generation – and that’s how they achieve their conclusions.”

In other words, the authors calculate a CO2 footprint of solar panels based on the assumption that we don’t use renewables for generation. Let me turn that around and assume we use only renewables, in which case the CO2 footprint becomes zero. Not the same can be said about fossil fuels.

Let’s call out this lack of logic, please.

JohnIL

I think there is a solar craze going on and many are jumping on the wagon even before they know where that wagon is going or how much is it to ride on it. I see people in my neighborhood getting panels but some of these houses have 17-year-old roofs or older. I have seen people cringe about the cost of removing panels to install a new roof. Is that built into the payback quote people get on how much they will save. OK, so your electric bill is cheaper, but now you are making payments on solar panels. I guess is your primary concern saving money, or saving the planet? Many claim every year the solar panel lose a little efficiency. What about hail damage or other storm damage? I do think many of the solar salesman are not being completely up front to potential customers. I think they tend to be overly optimistic and do not point out the potential issues such as maybe you should get a new roof before you install solar panels?? Reading many reviews, I see a similar pattern from customers who seemed to be upset with the experience from bad installations, delays, or billing and unfounded savings. Now they still have an electric bill and have to pay for solar panels. Many of these leases have an early out penalty and you have to pay a sizable fee for removing the panels. My only advice like with any new technology is ask plenty of questions, find reviews from current customers and don’t sign until you fully understand what you are agreeing to.

Rebecca Vanmeter

This is an amazing article and I appreciate you sharing these facts.

We discovered another expense that most don’t consider after talking with our insurance agent. We live in Florida, and it is highly likely you will have at least one full roof replacement during the life of your panels. Roof shingles lose a great deal of life expectancy in sunnier climates, understandably. Our homeowner’s insurance is already higher than other areas, but you have to add in the increased cost of insurance after you add solar panels. The cost to remove and replace EACH panel to accommodate roof repair/replacement is significant ($200 per panel here in ‘22). If insurance covers the repair/replacement, it’s covered, but if it isn’t, it’s on you to cover that extra expense.

After reading this article, with all the additional information we’ve gathered, as well as our age being a factor (we are nearly 70), we won’t be investing in solar panels. As much as we try to be green-conscious, it doesn’t seem a good fit for us.

I believe solar is our future and admire those who are investing in renewable sources.