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100 Percent Renewable Energy And Beyond

Thomas Gerke's picture
  • Member since 2018
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  • Jun 27, 2013

While many countries still discuss whether or not a 100% renewable energy system – or “just” a 100% renewable electricity supply – is even theoretically possible, Germans seem no longer bothered by such unscientific doubts. To make matters “worse,” some of them (including myself) are even convinced that a transition to a 100% renewable energy system can and should be accomplished within only a few decades’ time.

100RE-beyond-HeaderSome people might find this different perception of the problems we face to overcome the energy crisis of the 21st century so puzzling that they would rather choose to believe that the Germans have simply gone mad. Luckily, nothing could be further from the truth, and I’ve got a few nice examples that might explain the German mindset.

Think Big In Small Pieces

The German push towards a renewable future is often portrayed through the tunnel vision of the author’s worldview and the common themes of the political debates in her or his home country. Quite often, this kind of quality journalism turns a “minimum price law based on technology costs – in combination with guaranteed market access for all investors”(Feed in Tariff) into “generous, (tax-funded) subsidies”. Another popular myth among so called “professional journalists” is that what is happening in Germany is due to on some kind of “big government” program. Obviously, this domestic narrative-driven reporting is not very interested in looking at important details that could explain the big picture.

One of the most important details being missed by most of those common limited observations is the fact that the renewable energy success of the last decade was mainly driven by some pioneering regions, counties, and municipalities. Those local communities moved forward with conviction, while many others have remained dormant willingly or hindered by state governments that blocked investments by passing arbitrary anti-renewable regulations in favor of conventional power companies.

Luckily, some state elections and the spread of knowledge about the positive effects of renewable energy deployment for local economies have removed a lot of the brake blocks of the past. So, what can be accomplished within a decade if local initiatives get the opportunity to shape their energy future without obstruction?


Germany Top 3 Renewable Counties

To showcase what we know about what is at least possible, here are the top 3 out of 295 Landkreise (Counties / administrative districts) in terms of the renewable share in their regional power mix. Most of their success is based on investments during the last 10–15 years based on technology that is now outdated.

#3 Renewable Landkreis

#3 — Renewable Landkreis

#2 - Renewable Landkreis

#2 — Renewable Landkreis

#1 - Renewable Landkreis

#1 — Renewable Landkreis

This is Possible Everywhere

Those three counties are obviously just the tip of the renewable energyberg. The list of 100–200% renewable counties is longer, and the still rather long list of counties below 10% will get shorter in the coming years.

Here’s what we know: The advances of renewable energy technology and the growing understanding among local governments/business leaders creates a very fertile basis for a new wave of rapid renewable energy growth.

The newest generation of low-wind optimized wind turbines and the improved wind power–related land-use regulations in many German inland states offer great, previously underestimated potential for the cheapest renewable energy source.

13.8% of the land-area =  the provisional technical & environmental potential

13.8% of the land-area = the provisional technical & environmental potential — actual realizable potential is lower.

At the same time, the German solar industry and its remaining 80,000–100,000 employees are working tirelessly to emancipate themselves from the cost-covering feed-in tariff by diversifying their portfolio, offering smart energy solutions and building new alliances with other established German industries (storage, energy and micro grid management systems, etc).

That these further growth potentials will be unlocked is not mere wishful thinking on my part. Many regions across Germany have already declared their own 100% renewable electricity and even 100% renewable energy ambitions. They organize, hold conferences, and share their experiences in order to develop their individual road maps. Additionally, more and more regional utilities, and even some of the “former” nuclear and coal giants, have begun to transform their business models from primitive energy providers to modern managers of energy flows.


To add yet another piece to the utterly under-reported big picture, I want to encourage you to combine all these individual developments with the knowledge that solar and wind are now cheaper than the electricity rate for households, commercial customers, and in many cases even industrial customers – causing 30% of all German businesses to plan investments in renewable capacities.

If you do combine all the puzzle pieces, I am sure that you’ll see that we are only at the beginning of the energy revolution here in Germany, and producing enough renewable energy is definitely not the problemall those outdated 20th century devices that still consume fossil fuels are!



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Jani Martikainen's picture
Jani Martikainen on Jun 27, 2013

This is quite amazing. All serious literature on these issues is ignored as if the is some “journalistic” conspiracy involved. Some locations in Germany are listed as if they get their power (and) more from renewables rather than being powered by the same fossil fuel powered german grid everyone else is using. I probably do not even have to mention that there was no mention at all about CO2 emissions which quite a few consider as the main point. This is hardly surprising since while this “revolution” has been going on electricity sector in Germany has, in fact, not decarbonized. Better ignore such “unscientific” trivialities and carry on cheerleading. It is the faith that matters! 

I K's picture
I K on Jun 27, 2013

I wish Germany gods speed, the world needs a nation to try hard to dislodge coal gas and oil with wind and PV.

They will fail but some people need to see failure before they accept the underlying math was correct from the beginning

Thomas Gerke's picture
Thomas Gerke on Jun 27, 2013

Thanks for bringing two typical myths/misrepresentations up. 

1. New coal power plants:
I am certain that the coal power plants were not planed & build to be unprofitable. In fact when planning & permitting took place more than a decade ago, the corperations that commited billions in those centralized powerplants in the middle of the last decade propably expected these mid-load power plants to run 5-6000 hours a year and earn 60-100€ / MWh for their peak-load power (energy exchange). 

However in the real world a new coal power plant does not automatically mean actual electricity production. Renewables have outgrown all predictions and the construction of those coal power stations has been delayed for several years. Due to both realities, the market those power stations were planned & build for has changed forever – they are now “unprofitable” on arival and might never return the initial investment. 

You do understand that the market for conventional power has been shrinking and will continue to shrink, do you? That is the reality for the conventional (fossil/nuclear) power market.

The official target since 2008 has been at least a renewable share of 35% by 2020 – However this 5 year old minimum target is now considered to be a joke that will propably be reached by 2017/18. The current estimates are in the territory of 40-50%. 

If your fantasy world of “They sure didn’t build those power stations for nothing, so they will be running!” would be true, how can this happen?

I know that’s a wonderful gas power station, that should run instead of bloody coal power stations, but they sure didn’t build it to be mothballed for months right from the start. 

Read the article again… words like tunnel vision come up and you should also wonder about ownership & what economic interessts/players are competing for the energy system of the future. 

A little hint: The owners of coal power stations have not build the renewable capacities…

2. Emissions:
Yep, emissions from electricity generation have risen compared to 2011 and are also higher compared to 2009 – Yet they are still significantly lower than the pre-2009 recession emissions. Due to the implosion of the european ETS we will propably see yet another electricity export record for Germany this year. That means that neighbouring countries buy cheap electricity from german baseload power plants that is being displaced by renewables to displace more expansive power stations.

So while renewables push fossil electricity out of the distribution grid (especially solar & noon), other countries export their emissions to Germany at the same time. The result are rising net-electricity exports and rising / stable emissions in Germany.

Since it doesn’t appear that the EU will do something about the broken ETS soon, this will only stop when technical or economic limits for this export trend are reached, which should be the case after 2015. 

Fighting climate change is only one aspect of the German push for renewables and the ETS is the main instrument for this singular purpose. While I dislike more coal & emissions, you have to look there. 

Overall what is happening in Germany is not about what happens this year, next year or the year after that… The goal is to lay the foundations for an energy system that mainly relies on renewable energy from 2030 onwards, possibly being 100% renewable by mid-century. 

Having a limited horizon of a few months, clouds once judgement and is a childish exercise of ignorance IMHO. 

Thomas Gerke's picture
Thomas Gerke on Jun 27, 2013

You are absolutly right, these counties “only” produce a massive net electricity surplus from renewable energy sources after importing almost all their electricity during the entire last century.

Their accomplishments are meaningless, because they have not (yet) established an entire energy system all by themselves… they might have unmasked the ignorance / lies by countless “energy experts” who told the public just 15 years ago that renewable energy sources could theoretically only supply 10% of their local power needs and 5% of the national electricity needs– but who cares.

It’s all irrelevant, because they have not (yet) completly overcome the energy system that as been build during the last century. 

Nathan Wilson's picture
Nathan Wilson on Jun 28, 2013

Thomas, welcome to The Energy Collective.

This is a place where clean energy enthusiasts from all three groups (renewables, nuclear, and fossil fuels) can come together to have thoughtful discussions and hopefully learn from each other.

Since you apparently come from deep within the renewable world, you may not be aware of the most important criticisms of the “100% Renewables” scenarios.  As an American, I dismiss criticism that renewable resources are inadequate, we have plenty (though I’m sure there are places that don’t).  

For me, the big problem is the economic implications of the variability.  The US Department of Energy’s National Renewable Energy Lab (NREL) has done studies demonstrating that, for example, our grid can handle the variability of 20% or 30% wind with only minor upgrades.  As an engineer, I tend to assume that at higher penetration, energy storage will be required, and this will be so expensive, that most nations will simply continue burning fossil fuel instead.  (I know there are alternatives to storage, like super-grids, which I dismiss based on cost and politics, and dispatchable biomass, which I dismiss based on cost and land use).

So when I see articles celebrating regions that export large amounts of wind or solar energy, I look for indications that they are using energy storage.  If there is little or no storage, then they must be exporting variability along with the energy (which is no problem as long as the regional grid stays below 30% variable renewables).  When I see plans that indicate some nation will spend 1-2 decades getting to 30% variable renewables (hydro and lumber waste don’t count), I think, their kids will have to do the really expensive part (adding storage), what an unfair plan.  I would much rather leave my kids a fleet of nuclear plants that will make cheap power for 80 years, and a neat and tidy stack of waste canisters that takes up 10,000 times less space than a coal ash pond. 

I think its great that Germany has decided to phase out fossil fuels, and they are apparently wealthy enough to do it.  It’s just a shame they picked a route that is so expensive that it is unlikely that developing nations will follow (and those that try will be committing a crime against their poor people,since expensive energy makes all products more expensive).

I should also point out that due to very limited deployment of energy storage, there is not yet any evidence which would show which path Germany is actually on: 100% renewable or 30% renewable/70% fossil (note these both look the same until the storage buildup starts).

Nathan Wilson's picture
Nathan Wilson on Jun 28, 2013

“...the world needs a nation to try…”

It’s not as easy as that!  We already know a nation can’t succeed alone.  For it to be a convincing experiment, their neighbors have to participate as well (so yes, Europe, US, and Japan have to have “skin in the game” as well).

Of course, I would argue that the experiment would be perfectly valid in the presence of a 50% nuclear grid, since a 100% renewable grid can’t depend on a fossil fuel crutch anyway.  So we should clearly ramp-up nuclear while we do the renewable experiment, as a risk reducing* back-up plan.

* France, Sweden, and Switzerland have already succeeded in largely decarbonizing their electric grids by relying on nuclear and hydro, so the nuclear plan has low technical risk.  Japan has already demonstrated that nuclear accidents are nowhere near as dangerous as we have been lead to believe, and nowhere near as dangerous as fossil fuel use.

I K's picture
I K on Jun 28, 2013

The Germans nuclear power was producing over 150TWh at the beginning of this century with technology designed in the 60/70s and built in the 70/80s.

Compare that to the wind and solar fleet in Germany which produce roughly 80 TWh today

Come 2022 Germany may well be producing 150TWh from wind and solar so she would have spent three decades just replacing her nukes with wind mills and PV panels at a cost of probably in excess of 300B euros

Goodluck to her but things are going to get dificukt towards the end of this decade

I K's picture
I K on Jun 28, 2013

What can not be achieved small scale can not be achieved nationally.

So care to point to a single town which generates all its power from wind and or solar. That is to say with no connection to the national grid to export variability and import stability.



Of course tthere is no such town in Germany or the world as such the dream of fully wind or solar is thus far a pure fantasy


I K's picture
I K on Jun 28, 2013

Data from IEA 2009

Germany coal gas and oil generated electricity 350TWh

France coal gas ans oil generated electricity 50TWh

Uk coal gas and oil generated electricity 275 TWh

Italy coal gas and oil generated electricity 220TWh

Germany is held as the great champion of wind and solar yet is the most polluting of the four largest EU nations burning more coal gas and oil than the other both nominally and on a per head comparison. 


Robert Bernal's picture
Robert Bernal on Jun 28, 2013

100% is quite impossible, however, 90% IS possible… Simply extrapolate the following


And realize that it is the integration of renewables into the grid that motivates continued scaling and lower prices


Eventually, costs of storage will plumet, but it is not yet needed because renewables still have not been completely integrated into the grid.

I believe massive molten metal batteries will be the cheapest, most efficient way, though “only” about 70% efficient, which blows away hydrogen and it’s energy intensive storage and round trip efficiencies.

Perhaps, machine automation will produce LiFePO4 or similar giving 95% efficiency, however, their prices would have to drop by at least one order of magnitude…

Nathan Wilson's picture
Nathan Wilson on Jun 28, 2013

Eventually, costs of storage will plumet

It’s fine to believe this, but understand that it is faith-based, not science-based.  The notion that batteries are expensive because they are new and immature technology is simply untrue.  Batteries are made 100s of millions per year, and R&D budgets have been large since the cell-phone boom in the 1980s.  

Liquid metal batteries are a new twist, which should produce some cost reduction, but don’t fundamentally change the situation.  The Ambri batteries are only slightly different than existing sodium-sulfur batteries (which also use liquid metal electrodes), see NGK’s sodium-sulphur battery and Ambri liquid electrode/liquid electrolyte batteries.  The NGK battery is in volume production today, and has not gained market share against lead-acid batteries outside of Japan.  The main difference between the two is that the Ambri technology used a liquid electrolyte and gravity separation and NGK uses a ceramic electrolyte/separator (NGK is a ceramics company, so it’s a good fit).

The problem with batteries is that they inherently depend on surface area for power output (unlike solar salt for thermal energy storage, which depends only on volume).  So big batteries must be made from small units, and no economies of scale result (the new Ambri cells are flat like pizza boxes and are limited to about 1 inch thick, solar-salt tanks are shaped like round buildings and can be any size).  Flow-batteries were supposed to change this (by putting the reactants in tanks), but so far have not.  Flow-batteries are basically just reversible fuel cells that don’t involve gases;  the reversible ammonia fuel cell might be the best compromise, since the atmosphere can be used as a free tank for nitrogen, and the N2 separation cost is modest (fuel cells have poor round-trip efficiency due to the high cost of surface area).

If solar PV and batteries continue to drop in cost, then we may see PV deployments with 4 hours of storage for peaking and regulation (i.e. competing with hydro).  For baseload, nuclear and desert solar thermal with solar-salt will remain the most promising non-fossil options.  20-60 hour batteries which could smooth wind power will likely always be prohibitively expensive.  Electric cars can smooth the grid for an hour or two, but adequate smoothing requires someone to buy bigger batteries.

jan Freed's picture
jan Freed on Jun 29, 2013

Pardon my naivte,  but two data points are offered:

a. Germany coal gas and oil generated electricity 350TWh

b.  Total Wind Potential:  2,898 Twh


Sounds like they should move forward. What am I missing?

Robert Bernal's picture
Robert Bernal on Jun 29, 2013

Thanks for replying…

“The problem with batteries is that they inherently depend on surface area for power output”…

Well, that just blew away MY faith! I didn’t realize this simple fact about batteries.

CSP was one of my favorites until I realized PV was cheaper (and assumed the battery thing would happen during max grid integration). Now, it’s back to the steam cycle (or will the lessor renewable energy field afford Brayton?). Anyways, since we can direct sunlight into it, can it be heated by an electrode and wind electricity? I assume a heating element is very close to 100% efficient and that the vat is very close to that also, for days. The costs of the heliostat fields have to compare with the wind turbines (and line loss) but the benefits of being able to dump additional wind energy would seem to boost the molten salt vat as a duel purpose “machine” which could boost wind beyond max grid integration.

I have a hard time imagining PV going into it, though since that would take up a LOT of land. I think I need to learn more about the costs of ocean wind and global ocean wind maps because I read they can reach capacity factors of up to 40%.

Ivor O'Connor's picture
Ivor O'Connor on Jun 29, 2013

It’s fun watching Germany transistion across supplying 100% of it’s electricity via renewable to supplying all energy, including transportation, via renewables.

This weeks article on Audi producing Methane with the excess energy the grid can’t use is just the start,

“Yesterday, the world’s largest power-to-gas (P2G) facility went into operation in Germany. With a capacity of six megawatts, it is designed to make “green methane” out of excess green power. Cars could then run on this fuel.

German automobile manufacturer Audi is behind the facility, which it plans to use to fill up 1,500 models of the new A3 g-tron with some three million cubic meters of methane; each car would then be able to drive 15,000 kilometers annually – or 22.5 million kilometers for the entire fleet.

The facility will then have to run for 4,000 to 4,500 full-load hours a year. “It always switches on when there is too much wind or solar power on the grid,” explains Stephan Rieke, spokesperson of Etogas, a development partner of research center ZSW, which developed the system. The power to run the facility is purchased from the exchange whenever prices are very low because of excess wind and solar power.”


Ivor O'Connor's picture
Ivor O'Connor on Jun 29, 2013

Nathan Wilson pontificates as if he is an expert “It’s fine to believe this, but understand that it is faith-based, not science-based.”

Reality for many decades have shown batteries improving at about 8% per year.


Robert Bernal's picture
Robert Bernal on Jun 29, 2013

It would seem that people in general would want supergrids or even a global grid (for modern convenience) and I “know” that renewable energy solutions to excess CO2 demands them!

Paul O's picture
Paul O on Jun 29, 2013

Excuse me Ivor,

But at that rate a battery that could store 1 volt 100 yrs ago, would be storing about 257 volts today, same battery.

Do you want to revise and correct your remaks?

Ivor O'Connor's picture
Ivor O'Connor on Jun 29, 2013

I suppose you must not understand electronics Paul O or you would have never said “But at that rate a battery that could store 1 volt 100 yrs ago”. I think you have damaged your credibility beyond repair. (Except perhaps in a radio shack store.)

Ivor O'Connor's picture
Ivor O'Connor on Jun 29, 2013

Thanks for the explanation. Renewables are so cheap in Germany the new power plants using fossil fuels must export their energy to neighboring countries or go bankrupt. As other countries green up the just built fossil fuel plants in Germany will be the only ones left standing. So Germany is getting the best of all worlds by jumping so heaving on the renewable energies.

Paul O's picture
Paul O on Jun 29, 2013

Since you do appear to understand electronics so well, and since you think Nathan pontificates as though he were an expert,  I’m holding you to account for your semingly fantastic 8% per anum improvement in Batteries.

Why don’t you tell us what would happen to a 1 Volt battery pack, after 100yrs worth of 8% improvement.  I invite you to either  ammend, revise or withdraw your first comment about Nathan and Battery development, or else explain what the outcome of 8% improvements annually would mean to a 1 volt battery pack over a 100yr span..



Nathan Wilson's picture
Nathan Wilson on Jul 1, 2013

Yes, the energy stored per unit mass of batteries has been improving* (since around the time cell phones were deployed).  I would offer two caveats:

  • The energy per unit cost has not been improving much: lead-acid is still king, 100 years later.
  • Most products outside of the computer industry, improve for a couple of decades, then flatten out as the technology matures.  Computers have not flatted out yet, since transisters started out so much larger than the minimum possible size, and shrinking them improves performance.
  • The improvements in battery energy density have come largely from moving up the period table, from heavy to light: lead, nickel, and now lithium, which is the lightest metal there is.  The last step is to do lithium-air, then improvements will slow way down.

So my prediction does have some rational basis.  But I’m open minded if you have other information.

* improvements in energy storage of batteries have come primarily by increasing the Amp-hour capacity of cells.  The energy is the voltage times the Amp-hours, the voltage is determined by the electrode material: lead-acid cells have about 2V, NiCads and NiMHyd have 1.2V, and Lithium ion cells have about 3V.

Nathan Wilson's picture
Nathan Wilson on Jul 1, 2013

If electricity is used to drive a thermal energy storage system, the efficiency will be poor, since the turning the heat back to electricity will incure a 60-70% efficiency loss.  It’s different with CSP, as the heat must be turned into electricity anyway, so the storage does not make things worse.

Robert Bernal's picture
Robert Bernal on Jul 1, 2013

Just a thought process…

If a field of heliostats that put 100MWt into a molten salt vat costs more than say, wind turbines that puts 200MWe in, what’s the difference? Also, isn’t the chance of a sandstorm rather risky in some of the sunniest locations?

Anyways, it would be cool if the surface area required for batteries could be rolled up into the largest possible configurations… by machine. This way, less than half of the solar or wind field would be needed. 

The Chinese sell 180 Ah LiFePO4 cells (that I know of). Perhaps they could up it to 180,000 Ah?

Here’s the wikipedia on LiFePO4…

This idea might not be possible, though, due to the complexity of having to balance the cells for a utility scenario, most probably being far more difficult than for an electric car.

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