Cautionary Solar Tale

SOURCE: Ray Songtree (
SUBHEAD: The idea that solar voltaic panels will be substituted for fossil fuels in a clean energy low CO2 polluting future is false.

By Juan Wilson on 8 June 2015 for Island Breath -

Image above:An illustration showing our wonderful clean solar future provided by British Petroleum, the folks that destroyed the Gulf of Mexico. From (

I want to thank Ray Songtree for sending two excellent articles about the limitations of solar-voltaic power because of the variability of sunlight and requirements of the electric Grid, and the level of industrialization and intense energy needed to manufacture and maintain a solar powered world.

The articles below seem a reasonable arguments about the limitations of solar-voltaic panels supplanting the electric power grid we depend on today. However, I would add it appears these arguments are based on the assumptions that the
  1. Grid will continue with merely a change in the source of energy and
  2. Most of the electricity consumed will be through the Grid.
I take exception to those assumptions. It seems more likely that the infrastructure of the Grid will not be maintained (anymore than the Interstate will be maintained). For an increasing number of households that the electricity consumed will be the the power generated from their roof or yard.

In such a world it is difficult to have distributed wind energy; particularly on a small convoluted island like Kauai where many people live on small lots (limiting wind tower height).

Solar is much easier to achieve on a per household basis. It may be that adequate storage is expensive and will not be around long for “modern” living. But keeping a reading light or ham radio working through the night seems possible. To me that is more important than the convenience of refrigeration/freezing.

In my experience off-grid it is the 24/7/365 needs of refrigeration/freezing that are the heavy load. Fortunately for Kauaians the year round food growing capability of our climate could make refrigeration a non-requirement.

I lived in a van for a year on Kauai in 1971-2 without refrigeration. We kept a topless insulated cooler in the shade with a cheese cloth over it to store cheese, eggs, mayo and other “perishables" for many days. The most important item at night was a dome light in our 64 VW bus running off a 6volt battery. We could read, remove a splinter or write a note on a moonless night.

To me even solar is just a transition in the long haul of stepping down from worldwide industrialization. If I live another 25 years, and my solar panels die of old age, I doubt that there will be any affordable replacements, or for that matter, any coal fired furnaces needed to manufacture them.

The real challenge we will face is how we climb down from our levels of consumer consumption - not finding ways to substitute the energy to keep it all running. The sooner we climb back down to the ground the better off we’ll be.

Solar Device Industrial Infrastructure

By John Weber on 15 April 2015 for SunWebbber - 

In my posts and blogs, I have constantly spoken about the global industrial infrastructure that underwrites most manufactured things in our environment. Several passages in a novel brought an epiphany of how pervasive, how insinuated, how utterly complex these installations are. I have added those passages at the end of this essay.

Solar energy collecting devices have been challenged from several points of view. The Energy Return on Energy Invested has been noted in extensive research as being low. The dependence on fossil fuel has been noted. Solar enthusiasts act as if the industry stands apart from the fossil fuel supply system.

It is not separate from the present undulating supply plateau nor the scraping of the bottom of the fossil fuel barrel. We will never truly run out of fossil fuels, but the monetary cost and the environmental assaults defined by geology, geography as well as politics will certainly constrain our energy future.

My position has been that the underwriting by the global industrial infrastructure is a necessary consideration. All the things in our world have an industrial history. Behind the computer, the T-shirt, the vacuum cleaner is an industrial infrastructure fired by energy (fossil fuels mainly). Each component of our car or refrigerator has an industrial history.

Mainly unseen and out of mind, this global industrial infrastructure touches every aspect of our lives. It pervades our daily living from the articles it produces, to its effect on the economy and employment, as well as its effects on the environment.

Solar energy collecting devices also have an industrial history. It is important to understand the industrial infrastructure and the environmental results for the components of the solar energy collecting devices so we don’t designate them with false labels such as green, renewable or sustainable.

This is an essay challenging ‘business as usual’. If we teach people that these solar devices are the future of energy without teaching the whole system, we mislead, misinform and create false hopes and beliefs...

Video above: An overview of the Sun-Tech solar-voltaic panel manufacturing facility in China. From original article (

(the article concludes with)

...We have looked at charts and videos of making solar energy collecting devices, at the glass process and at the various aluminum processes. We viewed the manufacturing of an inverter that changes the DC energy to AC and the batteries for storing the electricity. And lastly, we viewed two videos on copper; one on production and the other on one of the many tools for which we use electricity.

Solar energy collecting devices have an industrial history. It arises part and parcel out of the global industrial infrastructure, the complexes that brings the many products of our age to our use.

[IB Publisher's note: This is a long detailed and comprehensive look at the industrial requirements for supporting a solar energy system. Read the rest at the source here (

Less than the sum of its parts

By Barry Brook 5 June 2015 for Brave New Climate

The fastest path to decarbonization would seem to be combining every kind of low carbon energy available – the so-called “all of the above” camp of clean energy advocacy.  The argument runs that different kinds of clean energy are complementary and we should build as much of each as we can manage.

This is not in fact the case, and I’ll show that a mix of wind and solar significantly decreases the total share of energy that all renewables can capture.  The “all of the above” approach to emissions reduction needs to be reconsidered.

In a recent essay Breakthrough Institute writers Jesse Jenkins and Alex Trembath have described a simple limit on the maximum contribution of wind and solar energy: it is increasingly difficult for the market share of variable renewable energy [VRE] sources to exceed their capacity factor.

For instance, if wind has a capacity factor of 35%, this says it is very difficult to increase wind to more than 35% of electrical energy.  Lets look at why this is so, and extend the principle to a mix of renewables.

The capacity factor (CF) is the fraction of ‘nameplate capacity’ (maximum output) a wind turbine or solar generator produces over time, due to variation in wind, or sunlight.  Wind might typically have a CF of 35%, solar a CF of 15% (and I’ll use these nominal values throughout).

Jesse and Alex’s “CF% = market share” rule arises because it marks the point in the build out of variable renewables at which the occasional full output of wind and solar generators exceeds the total demand on the grid.

At this point it gets very hard to add additional wind or solar.  If output exceeds demand, production must be curtailed, energy stored, or consumers incentivized to use the excess energy.  Curtailment is a direct economic loss to the generators.

So is raising demand by lowering prices.  Energy storage is very expensive and for practical purposes technically unachievable at the scale required.  It also degrades the EROEI of these generators to unworkable levels.

Jesse and Alex make this argument in detail, backed up with real world data for fully connected grids (i.e. not limited by State boundaries), with necessary qualifications, and I urge you to read their essay.

The “CF% = market share” boundary is a real limit on growth of wind and solar.

Its not impossible to exceed it, just very difficult and expensive. Its an inflexion point; bit like peak oil, its where the easy growth ends.  And the difficulties are felt well before the threshold is crossed. 

I’ve referred to this limit elsewhere as the “event horizon” of renewable energy.

So if wind is limited to say 35% of energy, and solar to 15%, can we add them together and achieve 50% share?  The Breakthrough authors seem to think so, writing that “this threshold indicates that wind and solar may be able to supply anywhere from a third to a half of all electricity needs”.  That would be a very considerable addition of low carbon energy.

But unfortunately this is not the case.

Here’s the problem with adding solar: it produces about half as much energy as wind for the same capacity.  And the capacity factor rule sets a limit on total variable renewable capacity.

So at the limit solar capacity is not additive to wind, it displaces wind, while producing less energy.

Any amount of solar lowers the share of energy that wind and solar together can acquire, and the optimal mix for decarbonization is all wind and no solar.

This is a general corollary to the capacity factor rule – adding lower capacity factor generation to the mix reduces the potential share of variable renewable energy.  It is the energy equivalent of Gresham’s Law – “Bad energy drives out good”.

Far from targeting a “mix of renewables”, we are better off targeting just the one with the highest capacity factor.

We should build wind and not solar.

You can see this dynamic in the following figure, which plots the limiting share of wind and solar energy (VRE) in the grid as a function of solar’s share of wind and solar capacity.  Adding solar capacity cannibalizes wind capacity, and reduces the total amount of low carbon energy that these sources can ultimately provide.  Solar is not additive to wind; its subtractive.

The situation becomes even clearer if we shift focus from installed capacity to energy delivered.  In the plot below, the x-axis now shows the fraction of wind and solar energy that is produced by solar.
Introducing solar energy into the mix causes a rapid drop in the maximum grid penetration of all variable renewable energy.  Wind alone could potentially achieve 35% of grid energy share. 

But with 50% solar, the maximum share that wind and solar together can achieve is just 21%.
In other words, building out solar effectively robs us of a whole climate stabilization “wedge”.

It should be remarked that this capacity factor rule sets too optimistic a limit.  The Breakthrough writers cite estimates that only 55%-60% of grid energy could be replaced by variable sources, due to stability requirements.  This means VRE share will struggle to exceed 60% of capacity factor, and the limits described above will be reduced by that factor.  So while wind alone could achieve up to about 21% of all electricity, a 50-50 mix of solar and wind is practically limited to only 12%.

This is a lot to give away.

So long as we only have a small amount of solar and wind we can build as much of either as we like.  The limit only becomes apparent at higher penetration.  But this happens much more quickly if there’s a lot of solar in the mix.

There may be good reasons to build solar in the early stages of a clean energy expansion.  The rate of emissions reduction matters, and while supply chains are developing, building both solar and wind might help.  But if this trajectory is to continue we will need to shift resources to wind fairly early on, and allow solar capacity to decline.

This should prompt a rethink of the simplistic “all of the above” response to emissions reduction, and the popular notion that there should be a mix of renewables.  If it doesn’t even work for wind and solar, does it work anywhere at all?  Its time to pick some winners, and support for renewable energy at scale should increasingly favour wind over solar.

And we should also think about how to decarbonize the remaining eighty percent of the grid that variable renewables can’t touch.

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