Tell me lies, tell me sweet little lies

Can't believe a word you say

      -The Knickerbockers

She was practiced in the art of deception

      -The Rolling Stones

Greetings

         In a way, I don't mind if Exxon or the Koch brothers lie to me.  I guess I expect that.  After all, they are "the enemy".  ( Unless DD is right that there is no "them" only "us").  But it kind of bugs me when I see ...ahem ...exaggerations coming from the "good guys" - the "non deniers".

        Like when the IPCC says we can avoid 2 degrees, but declines to mention that it means "we can get to 2 degrees, if someone invents a magical technology to suck up carbon."  Or Oregon passes a "historic". climate bill eliminating coal power by 2030., when the only coal plant in the state had already been slated for retirement by 2020.  

        Now we have the  IEA saying "Decoupling of global emissions and economic growth confirmed.  Likewise Climate Progress tells us Record First: Global CO2 Emissions Went Flat In 2014 While The Economy Grew

       Sounds pretty good, doesn't it?.  CO2 emmisions went flat in 2014!  Wow!    But wait a minute,  that's not exactly true. In fact,   CO2 emissions hit a new record in 2014!     (It is true that the rate of growth slowed  though) .    How about  CO2 concentrations in the atmosphere?  Did they "flatten"?   Well no .. in 2014, they rose by 2.17 ppm and in 2015 they jumped up by a record 3.05 ppm      

        Let's go back and look at the IEA press release again.   Lets' get behind the headline.  Here's what they say: "Global energy-related carbon dioxide emissions (CO2) – the largest source of man-made greenhouse gas emissions – stayed flat for the second year...."   OK, and the "energy related" emissions amount to about 30% of total emissions.   

      It doesn't cover emissions from other sources such as methane from livestock ,    or agriculture, where the news is not quite as good.  See this study .  

"When observations and models only take into consideration how much carbon dioxide plants and other biological activity pull out of the atmosphere the results can look promising – with the land actually absorbing the equivalent of about 25 percent of carbon dioxide from fossil fuel emissions and partially slowing down climate change.

“But we found that when you include the other two main greenhouse gases – methane and nitrous oxide – this completely changes the role of the land in that instead of having a cooling effect on the climate, it has a net warming effect,” said Benjamin Poulter, an assistant professor with a dual appointment in MSU’s Department of Ecology in the College of Letters and Science and the Montana Institute on Ecosystems.

        I suppose you could interpret these "good news" pronouncements is two possible ways.  The most generous would be to say that these folks know that people are getting discouraged, so they want to throw them a bone.  "Hey troops!, things are getting better!"   Were winning! "   Its probably a good idea to cheer people up, if you can.  After all February 2016 crossed the critical threshold, by averaging 15 degrees above pre industrial.     And on land the average was more than 2 c

         On the other hand, perhaps its an indication of panic.  Panic might be an appropriate reaction to James Hanson's latest study..   see e.g. Scientists Warn of Perilous Climate Shift Within Decades, Not Centuries

"The paper by Dr. Hansen and 18 co-authors dwells on the last time the Earth warmed naturally, about 120,000 years ago, when the temperature reached a level estimated to have been only slightly higher than today. Much of the polar ice disintegrated then, and scientists have established that the sea level rose 20 to 30 feet.

Climate scientists agree that humanity is about to cause an equal or greater rise in sea level, but they have tended to assume that such a large increase would take centuries, at least. The new paper argues that it could happen far more rapidly, with the worst case being several feet of sea-level rise over the next 50 years, followed by increases so precipitous that they would force humanity to beat a hasty retreat from the coasts.

“That would mean loss of all coastal cities, most of the world’s large cities and all their history,” Dr. Hansen said in a video statement that accompanied the new paper.

 For an interesting perspective on panic, see Ugo Bardi's recent post :  The climate emergency: time to switch to panic mode?

"The problem is that societies; specifically in the form called "states" do not normally show much intelligence in their behavior, especially when they are in a state of panic. One of the reasons is that states are normally ruled by psychopaths whose attitude is based on a set of simple rules, mainly involving intimidation or violence, or both. But it is not just a question of psychopaths in power; the whole society reacts to threats like a psychopath: with the emphasis on doing "something", without much concern about whether it is the right thing to do and what would the consequences could be. So, if climate starts to be perceived as a real and immediate threat, we may expect a reaction endowed with all the strategic finesse of a street brawl: "you hit me - I hit you."

A possible, counterintuitive, panic reaction might be of "doubling down" in the denial of the threat. That could lead to actions such as actively suppressing the diffusion of data and studies about climate; de-funding climate research, closing down climate research centers, marginalizing those who believe that climate is a problem; for instance classifying them among "terrorists." All that is already happening in some degree and it may well become the next craze, in particular if the coming US elections will handle the presidency to an active climate denier. That would mean hard times for at least a few years for everyone who is trying to do something against climate change. And, perhaps, it would mean the total ruin of the Earth's ecosystem.

The other possibility is to switch all the way to the other extreme and fight climate change with the same methods used to fight terrorism; that is, bombing it into submission. Of course, you cannot bomb the earth's climate into submission, but the idea of forcing the ecosystem to behave the way we want is the basic concept of "geoengineering".

In the world of environmentalism, geoengineering enjoys more or less the same reputation that Saddam Hussein enjoyed in the Western press in the 1990s. That's for good reasons: geoengineering is often a set of ideas that go from the dangerous to the impossible, all ringing of desperation. For a good idea of how exactly desperate these ideas can be, just take a look at the results of a recent study on the idea of pumping huge amounts of seawater on top of the Antarctic ice sheet in order to prevent sea level rise. If it were a science fiction novel, you'd say it is too silly to be worth reading.

However, it may be appropriate to start familiarizing with the idea that geoengineering might be the next world craze. And, perhaps, it is better to take the risk of doing something that could go wrong than to do nothing, considering that we have been doing nothing so far. Don't forget that there are also good forms of geoengineering, for instance the form called "biosphere regeneration." It is based on reforestation, fighting desertification, regenerative agriculture and the like. Removing some CO2 from the atmosphere by transforming it into plants can't do too much damage, although it cannot be enough to solve the problem. But it may stimulate also other fields of action against climate change; from adaptation to switching to renewable energy. Maybe there is still hope..... maybe.

No Direction Home

Blowin' and burnin' blinded by thirst

They didn't see the stop sign;

 Took a turn for the worst"

      - The Eagles

And I'm sorry when I say
that straight to this very day
It was the wrong way
     -Sublime

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Breaking News:
      New Study : "Trading Off Global Fuel Supply, CO2 Emissions and Sustainable Development", in Plos 1, predicts 1.5 by 2020, 2 degrees by 2030.    Authors assert that the accepted method of modelling energy use is overly optimistic, and  inaccurate .   See here , here 

   "In contrast our model shows that a dominant factor driving global energy demand is not energy use GDP^-1, but energy use person^-1 which is forecast to rise rises rapidly towards 2050, while the efficiency of production/conversion only gradually improves.

The model’s ability to account for these interactions provides international policy makers with new tools and insights to guide the development of improved global energy security models and to assist with the development of effective emissions reductions and poverty alleviation scenarios. Importantly these capabilities challenge the common assumption of the EIA and IEA that increasing efficiency (energy use GDP^-1) will solve our future energy supply problems.

______

Greetings

      As I see it, there are basically two routes away from overshoot.   One is to make necessary changes, and, to crawl back into sustainability.   The other is to let nature take its course.  (As  one sage has said, "If something can not go on forever, it will stop. ")

       Let's take a look at efforts to deal with the problem of CO2.    Oregon has just enacted a "ground breaking"  climate bill, the Healthy Climate Act..   Under the bill Oregon utilities will cut coal use by 2030  and be 50% fossil fuel free by 2040  (Oregon is already 43% hydro, thanks to the Columbia dams).

       We are told this bill is the most ambitious in decades     So, is this a formula that would avoid "dangerous" climate change?     Well, according to Kevin Anderson, in order to achieve 2 degrees, we would need all sectors ( not just  electricity)  to  "decarbonization " by 2040.   

"Of the available scenarios for peaking in 2020, says Anderson, 13 of 18 show hitting 2 degrees C to be technically impossible. (D’oh!) The others involve on the order of 10 percent reductions a year after 2020, leading to total decarbonization by 2035-45." 

       Decarbonize.  That's a 100%  reduction,  not 50%. .   So The Healthy Climate Bill,  doesn't quite do the trick, but maybe its a "step in the right direction".  Well,  unfortunately its  not really a step in the direction of 1.5 or 2 degrees.  That would be the "right direction".  Its  more of a step toward 3 or 4 degrees *.

      

       .  Here is a speech Anderson gave at the London School of Economics earlier this year.  

     He starts with an interesting quote from Richard Feynman,"For a successful technology, reality must take precedence over public relations, for Nature cannot be fooled."     This is important because, it seems that most of the encouraging messages we get about climate change are really public relations messages, designed to assure us that we can continue to have economic growth and avoid dangerous climate change,   As Anderson points out, this can only be achieved if you believe in magic.   The assumptions in the studies that support this optimistic view use one of two magical devices.  Most assume a magical technology, that will spring into existence and suck out the carbon .   The rest postulate time travel,  that is the models only work if you assume that CO2 peaked some time in the past.

       According to Anderson, this magical thinking is designed to divert us from the "inconvenient truth"  that in order to have a reasonable chance ( greater than 50/50)  of avoiding 2 degrees, we, in the west,  need to reduce emissions by 10% per year, until we are completely decarbonized by 2040.  

           OK, so far humans don't seem to be backing away from overshoot with any speed.    So, how about letting nature take it course.   How would that play out?    The best analysis of the likely path is still the Limits to Growth,  Although initially created in 1972, it has been continually updated, and continues to provide a useful guide to the way things may unfold .  

With some luck I can paste the critical graph here.

            The most recent effort to check the models accuracy was made in 2008, and it showed that the data, generally continues to follow the suggested curves.   But importantly,  this could not confirm when  the curves will peak, because at that point things were continuing to grow.    If the model is correct,  foot per capital, industrial output and services will all peak first. 

      One simple way to track services and industrial output, is by tracking GDP.  The IMF tracks what they call Gross Planetary Production.   Interestingly, this figure was reported to have dropped by 4.9%  in 2015,   a drop of the same magnitude as the Great   Recession in 2009.   It is too soon to tell whether this is merely a blip, or whether is represents a trend.  Interestingly, at least one economic forecaster predicts a similar drop for 2016.   See Morgan Stanley.   **  

             So, will "letting nature take its course" have the result of decarbonization by 2040.?   Not according to this analysis.  see here.     Unfortunately, even if were following the Limits to Growth model, the decline of industrial output is not steep enough.   The curve for industrial production in the limits to growth model is essentially a Hubbert curve -  it is symmetrical - the rise is about the same as the fall.   In order to achieve a 10%  reduction would need to be much steeper fall,  more like the  Seneca Curve

         So what will prevail, magical thinking or reality?   Stay tuned.

   -------

* (One may wonder why the bill, if it was so important was labeled as "absolute crap" by PUC Commissioner John Savage, The PUC was  invited by the Governor to _not_ testify on the bill.    Hopefully theiir concerns were addressed before passage.)  

To put a good face on it, lets say that although it would be a step towards an extremely dangerous climate, but, it might be  its a step that doesn't result in runaway climate change, or  perhaps not releasing the perma frost time bomb.     Perhaps its a step that does not result in huge swaths of the earth effectively uninhabitable?  See new Hanson Study.

**(It may be that GPP is falling not a result of feedback from planetary limits, such as peaking fossil fuels, increasing  pollution, but because of some other factor. As to limits on energy,it is unlikely that fossil fuel use will peak before 2025.  An alternate theory might be that the 1% , by taking the lion's share of income and wealth, has in effect stifled the demand that the economy needs to grow.   The median income in the US peaked in  1999, and is currently 6% below that level    Poor people spend their money as soon as they get,  rich people spend some, but often end of saving or investing it.     Maybe we should thank those 1%-ers , doing the or part for ecology! )

Devilish Details

I'm seeing

Puzzling evidence

     -Talking Heads

Who would have thought...?

It figures

     _Alanis Morissette

Greetings 

     Tip O'Neil once is said "All politics is local."  Perhaps the same might be said of energy.  For instance , it is well recognized that any benefits of driving an eletric car will depend on the fuel used to generate the electricity.  See PNAS study : here.   So, if if you fill up in a state that relies mainly on coal, driving your EV may be worse than your old  ICE.  On the other hand if you live in hydro heavy northwest, you will see some environmental benefit.

       How about the environmental benefits of solar panels?   The article below  here (h/t Ben) , provides an interesting analysis of pv panels.  The author reasons that  there are several factors that need to be considered :  The energy that goes into the panels. the energy required to transport it to where it is used, and the solar influx of the location where it is used .  

     Most  PV panels are made in China  (87%!), which has a notoriously dirty energy system.  They are shipped around the world, and may end up in a country with less than optimal sunny-ness.  Like Germany  (or Oregon).  The author  suggest that in such a scenario, you would still get some benefit - but much lower than advertised.   Here, he calculates the impacts , without transportation.

 "If solar modules manufactured in China are installed in Germany, then the carbon footprint increases to about 120 gCO2e/kWh for both mono- and multi-si -- which makes solar PV only 3.75 times less carbon-intensive than natural gas, not 15 times."  

     The author takes the analysis one step further, by analyzing the growth rate of the PV systems.  As we know, the carbon impact of a PV system is "front loaded" in the early years.  Thus there is a "burp" of CO2 at the beginning,  and the system is in carbon "debt" for a number of years while it is off setting grid power.  With an individual panel, the debt is paid off in the later years.  However in a growing industry, the payback from the early panel is swamped by the debt of  manufacture of the later panels.    The author attempts to look at this factor across the industry using "dynamic life cycle analysis"    He notes:

"This means that the net CO2 balance of solar PV was negative for the period 1998-2008. Solar PV power was growing too fast to be sustainable, and the aggregate of solar panels actually increased GHG emissions and energy use. According to the paper, the net CO2 emissions of the solar PV industry during those 10 years accounted to 800,000 tonnes of CO2. [16] These figures take into account the fact that, as a consequence of a cleaner grid and better manufacturing processes, the production of solar PV panels becomes more energy efficient and less carbon-intensive over time.

       This is kind of an odd result.   For now, we may actually be digging the hole deeper, while we think we are making things better.  Do we ever get out of carbon debt?    Presumably, once all the needed PV's are installed.  But , pretty soon we have start doing it all over, as the current PV's degrade and we have to replace them.  

       He does suggest  one possible way out.

"By carefully selecting the locations for production and installation we could improve the sustainability of solar PV power in a spectacular way. For PV modules produced in countries with low-carbon energy grids -- such as France, Norway, Canada or Belgium -- and installed in countries with high insolation and carbon-intensive grids -- such as China, India, the Middle East or Australia -- greenhouse gas emissions can be as low as 6-9 gCO2/kWh of generated electricity. [16] [20] [14-15] That's 13 to 20 times less CO2 per kWh than solar PV cells manufactured in China and installed in Germany. [25]

            When we consider "green power" it is easy to forget the industrial economy that is needed for its development, manufacture, installations, and operation.  For an interesting tour of the various industries behind PV panels - Take a look here

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How Sustainable is PV Solar Power?

Solar photovoltaic (PV) systems generate "free" electricity from sunlight, but manufacturing them is an energy-intensive process.

It's generally assumed that it only takes a few years before solar panels have generated as much energy as it took to make them, resulting in very low greenhouse gas emissions compared to conventional grid electricity.

However, the studies upon which this assumption is based are written by a handful of researchers who arguably have a positive bias towards solar PV. A more critical analysis shows that the cumulative energy and CO2 balance of the industry is negative, meaning that solar PV has actually increased energy use and greenhouse gas emissions instead of lowering them.

This doesn't mean that the technology is useless. It's just that our approach is wrong. By carefully selecting the location of the manufacturing and the installation of solar panels, the potential of solar power could be huge. We have to rethink the way we use and produce solar energy systems on a global scale.

Picture: Jonathan Potts.

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There's nothing but good news about solar energy these days. The average global price of PV panels has plummeted by more than 75% since 2008, and this trend is expected to continue in the coming years, though at a lower rate. [1-2] According to the 2015 solar outlook by investment bank Deutsche Bank, solar systems will be at grid parity in up to 80% of the global market by the end of 2017, meaning that PV electricity will be cost-effective compared to electricity from the grid. [3-4]

Lower costs have spurred an increase in solar PV installments. According to the Renewables 2014 Global Status Report, a record of more than 39 gigawatt (GW) of solar PV capacity was added in 2013, which brings total (peak) capacity worldwide to 139 GW at the end of 2013. While this is not even enough to generate 1% of global electricity demand, the growth is impressive. Almost half of all PV capacity in operation today was added in the past two years (2012-2013). [5] In 2014, an estimated 45 GW was added, bringing the total to 184 GW. [6] [4].

Solar PV total global capacity, 2004-2013. Source: Renewables 2014 Global Status Report.

Meanwhile, solar cells are becoming more energy efficient, and the same goes for the technology used to manufacture them. For example, the polysilicon content in solar cells -- the most energy-intensive component -- has come down to 5.5-6.0 grams per watt peak (g/wp), a number that will further decrease to 4.5-5.0 g/wp in 2017. [2] Both trends have a positive effect on the sustainability of solar PV systems. According to the latest life cycle analyses, which measure the environmental impact of solar panels from production to decommission, greenhouse gas emissions have come down to around 30 grams of CO2-equivalents per kilwatt-hour of electricity generated (gCO2e/kWh), compared to 40-50 grams of CO2-equivalents ten years ago. [7-11] [12]

According to these numbers, electricity generated by photovoltaic systems is 15 times less carbon-intensive than electricity generated by a natural gas plant (450 gCO2e/kWh), and at least 30 times less carbon-intensive than electricity generated by a coal plant (+1,000 gCO2e/kWh). The most-cited energy payback times (EPBT) for solar PV systems are between one and two years. It seems that photovoltaic power, around since the 1970s, is finally ready to take over the role of fossil fuels.

Manufacturing has Moved to China

Unfortunately, a critical review of the PV solar industry paints a very different picture. Many commenters attribute the plummeting cost of solar PV to more efficient manufacturing processes and scale economies. However, if we look at the graph below, we see that the decline in costs accelerates sharply from 2009 onwards. This acceleration has nothing to do with more efficient manufacturing processes or a technological breakthrough. Instead, it's the consequence of moving almost the entire PV manufacturing industry from western countries to Asian countries, where labour and energy are cheaper and where environmental restrictions are more loose.

Less than 10 years ago, almost all solar panels were produced in Europe, Japan, and the USA. In 2013, Asia accounted for 87% of global production (up from 85% in 2012), with China producing 67% of the world total (62% in 2012). Europe's share continued to fall, to 9% in 2013 (11% in 2012), while Japan's share remained at 5% and the US share was only 2.6%. [5]

Compared to Europe, Japan and the USA, the electric grid in China is about twice as carbon-intensive and about 50% less energy efficient. [13-15] Because the manufacture of solar PV cells relies heavily on the use of electricity (for more than 95%) [16], this means that in spite of the lower prices and the increasing efficiency, the production of solar cells has become more energy-intensive, resulting in longer energy payback times and higher greenhouse gas emissions. The geographical shift in manufacturing has made almost all life cycle analyses of solar PV panels obsolete, because they are based on a scenario of domestic manufacturing, either in Europe or in the United States.

LCA of Solar Panels Manufactured in China

We could find only one study that investigates the manufacturing of solar panels in China, and it's very recent. In 2014, a team of researchers performed a comparative life cycle analysis between domestic and overseas manufacturing scenarios, taking into account geographic diversity by utilizing localized inventory data for processes and materials. [13] In the domestic manufacturing scenario, silicon PV modules (mono-si with 14% efficiency and multi-si with 13.2% efficiency) are made and installed in Spain. In the overseas manufacturing scenario, the panels are made in China and installed in Spain.

For solar panels manufactured in China, the carbon footprint and the energy payback time are almost doubled

Compared to the domestic manufacturing scenario, the carbon footprint and the energy payback time are almost doubled in the overseas manufacturing scenario. The carbon footprint of the modules made in Spain (which has a cleaner grid than the average in Europe) is 37.3 and 31.8 gCO2e/kWh for mono-si and multi-si, respectively, while the energy payback times are 1.9 and 1.6 years. However, for the modules made in China, the carbon footprint is72.2 and 69.2 gCO2e/kWh for mono-si and multi-si, respectively, while the energy payback times are 2.4 and 2.3 years. [13]

At least as important as the place of manufacturing is the place of installation. Almost all LCAs -- including the one that deals with manufacturing in China -- assume a solar insolation of 1,700 kilowatt-hour per square meter per year (kWh/m2/yr), typical of Southern Europe and the southwestern USA. If solar modules manufactured in China are installed in Germany, then the carbon footprint increases to about 120 gCO2e/kWh for both mono- and multi-si -- which makes solar PV only 3.75 times less carbon-intensive than natural gas, not 15 times.

Considering that at the end of 2014, Germany had more solar PV installed than all Southern European nations combined, and twice as much as the entire United States, this number is not a worst-case scenario. It reflects the carbon intensity of most solar PV systems installed between 2009 and 2014. More critical researchers had already anticipated these results. A 2010 study refers to the 2008 consensus figure of 50 gCO2e/kWh mentioned above, and adds that "in less sunny locations, or in carbon-intensive economies, these emissions can be up to 2-4 times higher". [17] Taking the more recent figure of 30 gCO2e/kWh as a starting point, which reflects improvements in solar cell and manufacturing efficiency, this would be 60-120 gCO2e/kWh, which corresponds neatly with the numbers of the 2014 study.

Solar insolation in Europe and the USA. Source: SolarGIS.

These results don't include the energy required to ship the solar panels from China to Europe. Transportation is usually ignored in LCAs of solar panels that assume domestic production, which would make comparisons difficult. Furthermore, energy requirements for transportation are very case-specific. It should also be kept in mind that these results are based on a solar PV lifespan of 30 years. This might be over-optimistic, because the relocation of manufacturing to China has been associated with a decrease in the quality of PV solar panels. [18] Research has shown that the percentage of defective or under-performing PV cells has risen substantially in recent years, which could have a negative influence on the lifespan of the average solar panel, decreasing its sustainability.

Energy Cannibalism

Solar PV electricity remains less carbon-intensive than conventional grid electricity, even when solar cells are manufactured in China and installed in countries with relatively low solar insolation. This seems to suggest that solar PV remains a good choice no matter where the panels are produced or installed. However, if we take into account the growth of the industry, the energy and carbon balance can quickly turn negative. That's because at high growth rates, the energy and CO2 savings made by the cumulative installed capacity of solar PV systems can be cancelled out by the energy use and CO2 emissions from the production of new installed capacity. [16] [19-20]

At high growth rates, the energy and CO2 savings made by the cumulative installed capacity of solar PV systems can be cancelled out by the energy use and CO2 emissions from the production of new installed capacity

A life cycle analysis that takes into account the growth rate of solar PV is called a "dynamic" life cycle analysis, as opposed to a "static" LCA, which looks only at an individual solar PV system. The two factors that determine the outcome of a dynamic life cycle analysis are the growth rate on the one hand, and the embodied energy and carbon of the PV system on the other hand. If the growth rate or the embodied energy or carbon increases, so does the "erosion" or "cannibalization" of the energy and CO2 savings made due to the production of newly installed capacity. [16]

For the deployment of solar PV systems to grow while remaining net greenhouse gas mitigators, they must grow at a rate slower than the inverse of their CO2 payback time. [19] For example, if the average energy and CO2 payback times of a solar PV system are four years and the industry grows at a rate of 25%, no net energy is produced and no greenhouse gas emissions are offset. [19] If the growth rate is higher than 25%, the aggregate of solar PV systems actually becomes a net CO2 and energy sink. In this scenario, the industry expands so fast that the energy savings and GHG emissions prevented by solar PV systems are negated to fabricate the next wave of solar PV systems. [20]

The CO2 Balance of Solar PV

Several studies have undertaken a dynamic life cycle analysis of renewable energy technologies. The results -- which are valid for the period between 1998 and 2008 -- are very sobering for those that have put their hopes on the carbon mitigation potential of solar PV power. A 2009 paper, which takes into account the geographical distribution of global solar PV installations, sets the maximum sustainable annual growth rate at 23%, while the actual average annual growth rate of solar PV between 1998 and 2008 was 40%. [16] [21]

This means that the net CO2 balance of solar PV was negative for the period 1998-2008. Solar PV power was growing too fast to be sustainable, and the aggregate of solar panels actually increased GHG emissions and energy use. According to the paper, the net CO2 emissions of the solar PV industry during those 10 years accounted to 800,000 tonnes of CO2. [16] These figures take into account the fact that, as a consequence of a cleaner grid and better manufacturing processes, the production of solar PV panels becomes more energy efficient and less carbon-intensive over time.

Between 2009 and 2014, solar PV grew four times too fast to be sustainable

The sustainability of solar PV has further deteriorated since 2008. On the one hand, industry growth rates have accelerated. Solar PV grew on average by 59% per year between 2008 and 2014, compared to an annual growth rate of 40% between 1998 and 2008 . [5] On the other hand, manufacturing has become more carbon-intensive. For its calculations of the CO2 balance in 2008, the study discussed above considers the carbon intensity of production worldwide to be 500 gCO2e/kWh. In 2013, with 87% of the production in Asia, this number had risen to about 950 gCO2e/kWh, which halves the maximum sustainable growth rate to about 12%.

If we also take into account the changes in geographic distribution of solar panels, with an increasing percentage installed in regions with higher solar insolation, the maximum sustainable growth rate increases to about 16%. [23-24] Although more recent research is not available, it's obvious that the CO2 emissions of the solar PV industry have further increased during the period 2009-2014. If we would consider all solar panels in the world as one large energy generating plant, it would not have generated any net energy or CO2-savings.

The Solution: Rethink the Manufacture and Use of Solar PV

Obviously, the net CO2 balance of solar PV could be improved by limiting the growth of the industry, but that would be undesirable. If we want solar PV to become important, it has to grow fast. Therefore, it's much more interesting to focus on lowering the embodied energy of solar PV power systems, which automatically results in higher sustainable growth rates. The shorter the energy and CO2 payback times, the faster the industry can grow without becoming a net producer of CO2.

Annual net CO2 balance of the crystalline silicon PV industry at different growth rates for different combinations of countries of production and installation. Source: Briner 2009.

Embodied energy and CO2 will gradually decrease because of technological advances such as higher solar cell efficiencies and more efficient manufacturing techniques, and also as a consequence of the recycling of solar panels, which is not yet a reality. However, what matters most is where solar panels are manufactured, and where they are installed. The location of production and installation is a decisive factor because there are three parameters in a life cycle analysis that are location dependent: the carbon intensity of the electricity used in production, the carbon intensity of the displaced electricity mix at the place of installation, and the solar insolation in the place of installation. [16]

By carefully selecting the locations for production and installation we could improve the sustainability of solar PV power in a spectacular way. For PV modules produced in countries with low-carbon energy grids -- such as France, Norway, Canada or Belgium -- and installed in countries with high insolation and carbon-intensive grids -- such as China, India, the Middle East or Australia -- greenhouse gas emissions can be as low as 6-9 gCO2/kWh of generated electricity. [16] [20] [14-15] That's 13 to 20 times less CO2 per kWh than solar PV cells manufactured in China and installed in Germany. [25]

Sustainable growth rates of 300-460% are possible when PV modules are produced in countries with low-carbon energy grids and installed in countries with high insolation and carbon-intensive grids

This would allow sustainable growth rates of up to 300-460%, far above what's even necessary. If solar PV would grow on average at a rate of 100% per year, it would take less than 10 years to meet today's electricity's demand. If it would grow at the 16% maximum sustainable growth rate we calculated above, meeting today's electricity demand would take until 2045 -- with no net CO2 savings. By that time, according to the forecasts, total global electricity demand will have more than doubled. [26]

Of course, producing and installing solar panels in the right places implies international cooperation and a sound economic system, none of which exist. Manufacturing solar panels in Europe or the USA would also make them more expensive again, while many countries with the right conditions for solar don't have the money to install them in large amounts.

CO2 mitigation potential for crystalline silicon PV modules produced in China and installed in different countries. Source: Briner 2009.

An alternative solution is using on-site generation from renewables to meet a greater proportion of the electricity demand of PV manufacturing facilities -- which can also happen in a country with a carbon-intensive grid. For example, if the electricity for the manufacturing of solar cells would be supplied by other solar cells, then the greenhouse emissions of solar PV systems could be reduced by 50-70%, depending on where they are produced (Europe or the USA). [7] In China, this decrease in CO2 emissions would even be greater.

In yet another scenario, we could dedicate nuclear plants exclusively to the manufacture of solar cells. Because nuclear is less carbon-intensive than PV solar, this sounds like the fastest, cheapest and easiest way to start producing a massive amount of solar cells without raising energy use and greenhouse emissions. But don't underestimate the task ahead. A 1 GW nuclear power plant can produce about 11 million square metres of solar panels per year, which corresponds to 1.66 GWp of solar power (based on the often cited average number of 150 w/m2). We would have needed 24 nuclear plants -- or 1 in 20 atomic plants worldwide -- working full-time to produce the solar panels manufactured in 2013. [27]

What About Storage?

Why does the production of solar PV requires so much energy? Because the low power density -- several orders of magnitude below fossil fuels -- and the intermittency of solar power require a much larger energy infrastructure than fossil fuels do. It's important to realize that the intermittency of solar power is not taken into account in our analysis. Solar power is not always available, which means that we need a backup-source of power or a storage system to jump in when the need is there. This component is usually not considered in LCAs of solar PV, even though it has a large influence on the sustainability of solar power.

Storage is no longer an academic question because several manufacturers -- most notably Tesla -- are pushing lithium-ion battery storage as an alternative for a grid-connected solar PV system. Lithium-ion batteries are more compact and technically superior to the lead-acid batteries commonly used in off-grid solar systems. Furthermore, the disincentivation of  grid-connected solar systems in a growing number of countries makes off-grid systems more attractive.

In the next article, we investigate the sustainability of a PV-system with a lithium-ion battery. Meanwhile, enjoy the sun and stay tuned.

Kris De Decker (edited by Aaron Vansintjan)