It’s not where your solar panels came from that matters, it’s where they are going that counts

One of the most infuriating things about reading advice for people wanting to reduce their carbon footprint is the colossal lack of perspective people some folk have when it comes to cutting emissions.

There’s people unplugging their phone chargers but not their DVRs.  Worrying about where their food comes from, rather than what type of food it is.  Or recycling their plastic bags rather than just getting some reusables.

You see, perspective is quite important if you want to make sensible decisions.

The lifecycle emissions of solar panels

There’s a really interesting new study out that compares the carbon footprint of solar panels manufactured in Europe and China.

The basic result shows that because Chinese manufacturing is less energy efficient, and reliant on coal fired electricity, the Chinese panels have a bigger carbon footprint.  In fact the footprint of Chinese panels is double that of European ones, as you can see in chart from the study below.

solar panel origin

Looking at this graph it is tempting to think that we should all be buying European (RER) solar panels rather than Chinese (CN) ones.  Or that ‘you’d better buy locally‘ like with your vegetables.  That’s certainly the message I’ve seen in how this paper was covered around the web.

And you know what, the local vegetable analogy is perfect.  Because if you focus on food miles you’re only looking 10% of the total foodprint.  And with solar panels their origin is even less significant.

Let’s get some perspective.

Where are your solar panels going?

When it comes to carbon emissions the most important factor about solar panels is not where they are made but where they are deployed.

If the solar electricity they product displaces coal fired electricity it will save 30 times the extra footprint of Chinese panels, 14 fold that difference if they displaces natural gas, and nothing at all if it displaces hydro or nuclear.

Looking at the data above the estimates for multicrystalline silicon are about 32g CO2-e/kWh for European panels and 68g for Chinese panels.  For some proper perspective lets compare these two to the average carbon intensity of consumed grid electricity.


Can you see the solar panel emissions?  They are the lines down at the bottom (click to enlarge). The 36 g difference between Chinese and European panels is a drop in the ocean.

I find it baffling that anyone could worry about where their panel comes from without first thinking about what electricity their solar will displace. This graph shows the average grid intensity, which although it is a good guide doesn’t always tell you the full story.

In coal heavy places solar does tend to eat into coal emissions, like it has done in Australia.  But if the grid is more mixed if often displaces the sources with high marginal costs and greater flexibility, so for example in Germany it has largely impacted natural gas. Lastly if you live somewhere with a huge hydro resource (Brazil) or nuclear dominance (France) the carbon benefit of solar is minimal.

Carbon tariffs on solar panels? Seriously?

As a bit of a carbon wonk I quite liked the European vs Chinese solar panel study.  I always enjoy an interesting lifecycle analysis. But one of the conclusions left me cold.  Here it is:

We propose a break-even carbon tariff model for the international trade of silicon-based PV modules, indicating an appropriate carbon tariff in the range of €105–€129/ton CO2.

Don’t get me wrong I see how you could jump to proposing a carbon tariff, particularly given some of the solar panel dumping China has been doing, but surely the authors must appreciate the colossal irony of a imposing a carbon tariff just on solar panels?

For a quarter of a century Europe and the US have been outsourcing heavy industry (an its emissions) to China.  The result is the Europe’s consumption footprint is 20% bigger than its terrestrial emissions, while for the US it is 10% larger.  In China’s is 21% less, because a quarter of its emissions result from producing the world’s stuff.

Look at the map below from Consumption based accounting of CO2 Emissions by Steve Davis and Ken Caldeira showing the net export of emissions embodied in products.


Given that Europe has a net carbon debt to China of 300 Mt CO2 each year, while for the US this figure 400 Mt CO2, the idea that we should put a carbon tariff on just a few megatonnes of solar panel emissions is pretty surreal.  I’m all all for a global carbon tax, but one just for solar panels is a lot more about protectionism than it is about environmentalism.

We can’t spend decades filling our homes with cheap goods made in China, from cheap labor and un-taxed dirty energy, and then decide we need a carbon tariff just for solar panels (a technology that helps to cut carbon).

Let’s take a look at what solar power looks like in the real world.

The solar boom is Made in China

In my endless reading of energy and environment blogs there is no subject that people get more excited about the beginning of the solar boom we have seen in recent years.

Again and again I see people using this remarkable ‘Swanson Effect’ chart from my old colleagues at BNEF to explain whats going on (this is the first time I’ve used it as I prefer to look at total system cost).

swanson effect

Due to this incredible drop in prices the installed capacity of solar has increased more than ten fold in the last 6 years.  Why is solar so cheap you ask? Why are all your electronics so cheap?  China.

In the graph below I show the world’s top 10 solar manufacturers for 2013.  The ones in red have the majority of their manufacturing based in China.

top solar manufacturers

That’s right.  Seven of the world’s top 10 solar manufacturers are based in China.  Sharp and Kyocera are in Japan, while First Solar was in Ohio and Malaysia last time I looked.  There are no Europeans in the Top 10, the REC Group is its leader at 14th.

The beginning of the solar boom we are seeing at the moment may have started in Germany, but it’s made in China. Without cheap Chinese panels a great share of current installation simply wouldn’t exist and few people would be getting so excited about solar. If you wan’t to buy something European then grab yourself a quality inverter from SMA, Xantrex or PowerOne.

And remember, with some horribly bastardized words from the wondrous Ella Fitzgerald:

 It’s not where your solar panels came from that matters, it’s where they are going that counts

  • Bob Ashworth

    Hi Lindsay. I hear people (usually those who don’t want to see the solar boom), saying that Chinese made panels are proving unreliable. They never provide any evidence and I personally don’t believe it to be true.

    Have you come across any figures on panel reliability?

    • Lindsay Wilson

      Its like anything made in China. The first few years are a bit crap, then things get better and at a certain point not only is there stuff far cheaper, but it is also up to top quality. Perhaps not the best, I like the Japanese, but very good. You still need to get the good stuff from China though. The californians do the best testing. Go to their site, divide the PTC by the wattage and if its over 90% then its solid. This is what they call the performance ratio:

    • Randy

      Some no name brands do suck and are unreliable. If you buy some Grade A monocrsytaline panels, I doubt you’ll have any issues though.

      I like Ramsond. Their panels are cheap and high quality.

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  • Peter ritchie

    Hey Lindsay,
    Great post; maybe my favourite so far. One of my favourite terms these days is “embedded carbon”, which so few people seem to lend their attention. We in the West are under this perverse illusion that somehow China is ultimately to blame for so much of the planet’s carbon woes. Don’t get me wrong, they have their place in the fray, but where do we privileged Westerners think all our great “stuff” (and we’ve got A LOT of it) comes from? Folks, there really is no free lunch; modern Western society would not exist were it not for China.

    On the topic of the quality of Chinese panels, I will say this. My panels were made by Yingli which, as your data shows, is the world’s largest manufacturer. Yingli is an ISO9001 and ISO140001 company which has won numerous awards for their product quality, environmental initiatives and employment practices. In short, they are a world class company with a world class product. So far, my array has performed flawlessly and my installer has had only positive feedback on Yingli products. Could it be that the people questioning the quality of Chinese manufacturing quality are maybe a bit jealous?

    North America has fallen behind other parts of the world when it comes to innovation and quality of manufactured goods and I would contend that this has happened because we have been happy to farm out this work to the lowest bidders, so that we may live our hugely subsidised lives of plenty. Here in Canada, we’d rather dredge bitumen out of the ground and ship it to China, so that they can do the heavy lifting from which we ultimately benefit.

    I’m sure many would beg to differ with my analysis but your data would seem to support my position.

    Keep up the great work.

    p.s. My panels are in a part of Canada heavily reliant on coal for electricity production.


    • Lindsay Wilson

      Yingli score well on the Californian testing. I think they’re extremely good in terms of value for money. I’ve got Sharp panels myself. Our roof was pretty small so I needed 19% efficiency just to squeeze 3.29 kWp on. Yingli have bought nearly every other billboard at the World Cup 😉 Must be spending a fortune on it

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  • Milton D Beattie

    While the Crazies argue about how to calculate how little of the Green Gas of life they are allowing into the ecosystem…The sane world realize the ludicrous lie and that the Green Gas of Life on Earth Needs to be Restored to historic abundance.

    Sweet Dreams in the Crazy house…..enjoy the mad crusade hating of all that is Good and Nature Blessing!!!

    Don’t forget to flagellate yourselves for breathing! LOL