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Nation's Largest Grid Operator: Huge Renewables Expansion Won't Be a Problem

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  • Mar 12, 2014

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John Moore, Senior Attorney – The Sustainable FERC Project, Chicago

PJM Interconnection, the nation’s largest power transmission grid organization, announced last week that wind and solar power could generate about 30 percent of PJM’s total electricity for its territory covering the Mid-Atlantic region and part of the Midwest by 2026 without “any significant issues.” That’s engineer-speak for “no big deal.” Even better, we would see more clean power at less cost and with far less pollution than our current mix of coal and natural gas power plants.

PJM’s new renewables integration report, prepared for it by General Electric, is required reading for anyone who questions the ability of the electric grid to handle large amounts of wind, solar, and other renewable energy. GE estimates that about 113,000 megawatts (MW) of installed wind and solar power resources (including distributed/generation), could produce about 30 percent of the region’s total energy. That’s enough energy to power 23.5 million homes annually. Here’s the breakdown of the resource mix in one of the scenarios studied in the report:

Resource Mix.png

Significant benefits from more clean energy

The report estimates that 30 percent wind and solar power in PJM would bring the following benefits:

  • 40 percent less carbon pollution than “business as usual.”
  • Lower average energy prices across PJM’s footprint – because wind and solar would avoid $15.6 billion in coal and natural gas fuel costs.
  • Very little additional power (only 1500 MW) needed to support the minute-to-minute variability of the renewable power (like when the sun doesn’t shine or the wind doesn’t blow).
  • No additional operating (known as “spinning”) reserves needed for backup power. (Wow!)
  • 44 percent less gas-fired generation and 21 percent less coal-fired generation—which also reduces the amount of carbon pollution emitted into the atmosphere.

The benefits, which really are stunning, derive primarily from several facts: 1) solar and wind power have zero fuel cost, which makes up most of the price of energy; 2) these resources are now commercially available and competitive with other power; 3) they produce zero carbon and other pollution; and 4) PJM’s large size over 14 states significantly reduces the magnitude of weather-caused variations in power output that can occur during the day and night.

What grid changes may be necessary?

Getting all of this additional clean energy will require more transmission lines, which PJM’s study estimated would cost $8 billion – which is far less the $15.6 billion in energy savings. But even that’s probably an exaggeration, since PJM’s study looked only at renewable energy expansion inside PJM. It didn’t consider, for example, the savings from importing some of the wind power from the Dakotas, Minnesota, Iowa, or other parts of the wind-rich Midwest and Great Plains. When you factor in those possibilities, the total transmission cost of achieving the 30% renewables integration could be lower than PJM’s predictions.

The study also recommends several relatively modest steps that PJM can take to successfully integrate these resources into the system. They include changes to the way PJM operates its energy markets and dispatches power on a minute-to-minute basis, taking a more detailed look at reserve requirements, and potentially improving the “flexibility” of so-called “base load plants to better integrate them with renewable energy resources.

Looking to the future/next steps

This study gives consumers, states, utilities, and others food for thought in several areas:

First, it’s clear that the grid can handle high levels of renewable power without compromising reliability. Of course, we already know this because the Midwest and Texas grids have seen wind energy constitute a significant portion of the power on the grid at a given time. The PJM study affirms that the grid can handle much higher power levels. It also provides a stepping stone to evaluating the impacts and savings of even more renewable power on the grid, which will be a top priority for states looking to satisfy the U.S. Environmental Protection Agency’s upcoming carbon pollution rules for existing power plants.

Second, as conventional power sources become less of the total energy production mix, power markets will need to evolve to encourage the development of complementary conventional resources. This is a critical point. PJM’s study shows that existing coal and gas resources are going to suffer revenue losses; indeed, PJM even suggested that it might be necessary to consider raising energy prices to compensate for the lost revenue. No, no, no. A better way is to look into redesigning PJM’s existing long-term power supply market (called a “forward capacity market”) so that it, in combination with reasonable state power preferences, assures the right supply of conventional power sources are available to support renewable power.

Third, PJM’s study was done in a relative vacuum; it didn’t consider how several grid regions, working together, could manage significantly more clean power. PJM and the other grid operators across the country need to work more cooperatively: do the studies and other work necessary to show states across the country that power-sharing (literally) saves even more money than for each region to plan for its own resources. FERC has encouraged this cooperation by issuing interregional coordination requirements in its landmark Order 1000 (more about that here) but the regions can do more, and they don’t need to wait for further instructions from Washington.

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Paul O's picture
Paul O on Mar 11, 2014

Where does it say that:

” that wind and solar power could generate about 30 percent of PJM’s total electricity for its territory covering the Mid-Atlantic region and part of the Midwest by 2026 without “any significant issues.”

I can’t find it in any of your links.

Robert Bernal's picture
Robert Bernal on Mar 12, 2014

You say that the report says that 30% renewables will cut 40% of CO2 emissions. How can that be?

100% fossil fuels = 100% CO2 emissions, cut 30% of that (by use of solar and wind) and you will have LESS than 30% CO2 reduction (unless there is NO loss of efficiency of natural gas back up due to cold starting).

This is how to dramatically reduce humanity’s excess CO2:

  • Deploy high temp melt down proof nuclear reactors such as molten salt reactors coupled with the same turbines used for natural gas on the global level!

We will replace coal (baseload) with such nuclear because it is safer and (far) longer lasting than the light water reactor of today (and because the waste issue is also dramatically reduced!).

Once machine mass produced solar and wind “takes off” (as predicted), more natural gas will be needed as back up (due to increased intermittancy). However, LESS CO2 will be emitted because it will be mixed under perfectly ideal (efficient) conditions in the turbine (already hot and because fission and renewables spits out almost no CO2). As the the renewables compete for ever more of the energy marketplace, eventually, less nuclear (per unit of population) will be needed until the optimum “renewable – NG – nuclear” mix is utilized.

Further on, machine mass produced batteries should be cheap enough to back up the renewables (thus less new melt down proof nuclear build ups). But the nature of growth required for developing a decent planetary civilization without excess CO2 dictates that we always need some amount of steady baseload and that MUST be nuclear (NOT coal)! There is no other way until fusion is developed unless we use self replicating machines to suck up and sequester the excess CO2 out of the air. That would not prevent the ill effects from coal pollution. Nuclear PREVENTS the ill effects. That is empirically proven by the death per gigawatt hour data of various different power sources.

Nathan Wilson's picture
Nathan Wilson on Mar 12, 2014

This report does not appear to add much new info compared to the older NREL 20% wind and EWITS studies.

One super important issue that is implicit in much of the report (but neglected in this article) was the compatibility and benefits of the substantial nuclear power fleet in the PJM grid with the studied renewables.  As shown in figure 8 of the executive summary, nuclear and hydro compose about one third of the annual electricity production; figure 20 shows that nuclear alone supplies about 30 GW or about 30% of the total generation.  The reason going to 30% renewables was able to produce a 40% drop in CO2 emissions (instead of 30% or less) was that fossil fuel output shrank to absorb all of the renewable power, with nuclear and hydro staying unchanged.  

Between the 20% renewable and 30% renewable senarios, there was no apparent need to drop nuclear output, demonstrating compatibity.  The “duration curve” in figure 2 shows that the nuclear component could easily double to 60 GW in the 20% renewables scenario with low curtailment, and could even grow by 10 GW or so with 30% renewables.

Another difference between the report and this article is the a-typical data chosen for the pie chart (which shows the “high-solar” scenario).  Most of the scenarios studied were low solar (perhaps reflecting the higher cost of solar, or simply that GE is big in wind but not solar).  Also, the pie chart shows nameplate capacity, not fraction of annual generation; since solar has a much lower capacity factor, the annual energy produced by solar is much less than wind in all of the scenarios.

Cynically (dishonestly?), the economic studies in the report focused on the fuel savings, and completely ignored the capital cost of the renewables (although the EIA does provide costs for renewable power, which are roughly double the cost of the fuel savings).  They also uses oddly high costs for fossil fuel ($4-8/MMBTU for fossil gas).  They leave it as a topic for further study to determine the size of the “capacity payments” which will be required to keep the fossil plants from closing down (they are needed for reliability) in spite of their reduced capacity factor and revenue.

No mention was made at all of what comes after 30%, or how the renewables will effect grid evolution.  For example, we know that in France, nuclear and hydro work well together to eliminate nearly all of fossil fuels from the grid.  The 114 GW of solar and wind added in the scenario from the pie chart  are already quite big compared to the 100 GW average PJM demand; increasing curtailment (discarding produced energy) and expensive energy storage would appear to be the next steps.  Public resistance to wind farms in populated areas was also ignored.

Bas Gresnigt's picture
Bas Gresnigt on Mar 12, 2014

“… that fossil fuel output shrank to absorb all of the renewable power, with nuclear and hydro staying unchanged.”

Here hydro is quite flexible. They change their output between zero and 100% fast depending on the whole sale price, thus maximizing their profit.
Why not in USA???

…what comes after 30%,…
Seems logical, just check the German scenario: 80% renewable in 2050.

Experts here estimate that at 2030 wind+solar+storage will be much cheaper.
E.g. PV rooftop solar ~3-4cent/KWh, large scale solar below 3cent/KWh.

With 30% wind+solar there will be days when those produce all electrictiy needed (check Denmark).
As the variable costs of solar+wind are near zero, wholesale prices will go down to <$1/MWh or less…

So power plants will have to calculate with average load factors of 50% or so. Especially if the share of wind+solar rises more.
I doubt whether a nuclear plant that can throttle to only 40% can survive… 

Robert Bernal's picture
Robert Bernal on Mar 12, 2014

Thanks for the explanation about how 30% renewabes causes a 40% cut in CO2.

Bas Gresnigt's picture
Bas Gresnigt on Mar 12, 2014

… that 30% renewables will cut 40% of CO2 emissions. How can that be?
Assume nuclear produce 30%. So fossil 70%. Then 30% renewable imply that fossil produce only 40%, which implies a GHG reduction of 43% without efficiency change of fossil.

With more than 35% produced by renewable, there is no place for base load plants as then there will be days that renewable produce >100% of what needed.

Denmark estimates that with 50% produced by wind turbines, they will have >100days during which wind produce >100% of what is needed…

New nuclear
Even in an optimistic scenario, a new to design (gen.IV = melt down proof) nuclear plant, will start in 2030 earliest. So it has to operate in the 2030-2080 time frame.
In 2050 normal solar panels will have ~35% yields (now ~16%) and be cheaper. 
Solar foils that one can glue to the wall that have same yield as present panels, are then common.
20MW wind turbine with CF>50% in the windy plains.

Which investor would be prepared to invest billions to develope such new plant?
Especially since it is clear that that plant will have to deliver against a much lower KWh price, while having a much lower capacity factor, than the new plant at e.g. Vogtle or Hinkley.

I am interested to see a positive business case for such a nuclear adventure?
I really do not see it.

Paul O's picture
Paul O on Mar 12, 2014

I dislike when people play with words for an agenda.

Three Questions/statements:

1) Where is the link. Show us a link so we can see what Denmark actually said, and not have to trust your interpretation of what they said.

2) There are 365 days in a Year, not 100 days.

3) If Photovoltaics (or even windmills) produced 220% of daily needed power in daytime, and Zero power at night, it could still be spun as providing greater than 100% of daily power


Show us the link.

Bas Gresnigt's picture
Bas Gresnigt on Mar 13, 2014

1. Denmark’s target of 50% of its electricity produced by wind in 2020, is part of their plan towards 100% renewable regarding all energy in 2050. Just google a little an you find it.

2. That is correct, so they need to exchange with Germany/Norway/Sweden.
An actual picture of their im-/export status.
They reached last year already >100% of all electricity produced by wind during a few days.

3. So some storage is needed. If only for the night, that will become cheap.

Paul O's picture
Paul O on Mar 13, 2014

No I won’t “Google it”. You should Just explain yourself clearly or put up a link to make your point.

So if Denmark is hoping to rely on Germany etc, then who’s Germany to rely upon? What’s the guarrantee that their needs will compliment each other rather than be concurrent? Why would anyone want to stake their energy future on a gamble of patch work systems?

The reason I reject this sort of thing is that it seems to be based on a belief system rather than the need for Carbon free energy alone. Photovoltaics etc do produce energy, Yes, trying to force them into a role they don’t work well in, just because of a quasi religious hatred for nuclear power is riddiculous.

Bas Gresnigt's picture
Bas Gresnigt on Mar 13, 2014

Denmark is ~15years ahead in the transition towards 100% renewable. E.g, only energy neutral houses get a building license in Denmark. So if anything Germany follows Denmark.

It is no gamble. The Germans spent ~€200million for scenario studies covering the 2000-2050 (80% renewable) period. They have institutes that study progresss and propose improvements.

The Energiewende is not based on a belief system, but on solid figures and predictions, that are adapted every few years. Just check at the Fraunhofer institute or Agora.

It doubled the reliability of electricity delivery (av. total yearly outage time now 15minutes, UK 60minutes, USA 120 minutes if outages due to extreme weather are not counted).

Bas Gresnigt's picture
Bas Gresnigt on Mar 13, 2014

…we always need some amount of steady baseload and that MUST be nuclear…
An area that produces ~50% of its electricity with wind (Denmark in 2020) will produce more than needed during ~100days (~27% of the time). So during that 27% of the time, whole sale prices will be near zero as the variable costs of wind and solar are near zero.

That implies that other electricity generators should shut down or face additional losses.
Hence I do not see a place for base load plants in the renewable future. Especially not since the share of wind+solar will increase towards 70% or more.

German institutes predict load factors of ~50-60% for power plants (their produced electricity only needed during <4000hrs/a).
This worsens the already bad economic picture of nuclear

Nathan Wilson's picture
Nathan Wilson on Mar 13, 2014

Here hydro is quite flexible. …Why not in USA???

Yes, no doubt this is true in the short term.  It is the annual output that stays the same.

With 30% wind+solar there will be days when those produce all electrictiy needed (check Denmark). 

As the variable costs of solar+wind are near zero, wholesale prices will go down…

Yes, this is exactly the problem with wind and solar.  At 30% of generation, any new wind and solar will produce all of their electricity at a time when prices are low, and no addition electricity is needed.  Fossil fuel lock-in is the likely result.  For nuclear, at least the electricity will be needed and rates will be high most of the time (nuclear also has very low variable costs, plus nuclear plants will earn capacity payments).  

With cheap storage, solar could become appealing in southern areas.  However in the North, winter electricity demand is higher than in the summer, and there are enough cloudy days that a solar plant with storage that makes power 24 hours per day in the summer only produces an annual capacity factor of 50% or so.  Again, fossil fuel gets locked in for winter use.

Also note that batteries which are cheap enough for electric cars are still too expensive for grid storage.  For a battery price of $100/kWh (several times cheaper than today), a car with double the battery of a Leaf (50kWh, or about 160 miles range) would spend $5,000 for the battery; such a car would be very successful if it could survive daily cycling to 25% depth of discharge for 10 years.  This gives a cost per cycle of $100/kWh/25%/365/10 = $0.11/kWh, before interest or charging energy are added.

Paul O's picture
Paul O on Mar 13, 2014


The Germans ….

1) Shut down their nukes Which were quite safe….without having had storage solutions ready to go

2) They resorted to burning more Lignite coal….and burning more particulate emmitting biofuels

3) The idea of a future (adequate ) storage system is an act of blind faith.

This sounds like a belief based system to me.

Also, the whole anti nuclear movement which spawned Energiewende is fundamentally a belief based ideal, and there is no guarrantee it will work or work well.


Bas Gresnigt's picture
Bas Gresnigt on Mar 13, 2014

1) “Germans … shut down their nukes. Which were quite safe…without having … storage...”
Though more safe than the unsafe NPP in The Netherlands: Still, a simple 200ton airliner/freight plane is enough to change those in another Fukushima Daiichi…

Germany had enough spare and storage in place as shown in winter 2011/2012. Tthey have ~35 pumped storage facilities and connections mountain countries Austria/Switzerland and Norway/Sweden. In addition the organized stand-by of 3 fossil plants, only one had to run a few weeks as spinning reserve.

2) “They resorted to burning more Lignite coal
This is one of the many phantasies.  The opposite is true. Please check the real figures.
This graph shows the changes in the last 6 years.

3) “…idea of a  future (adequate) storage system is an act of blind faith…
In 2000 they did the same with PV and Wind.
I have no insight knowledge of battery systems, but I have about PV-cells and wind turbines.

I shared the estimation that costs of PV-cells would come down greatly, as it did. Though less fast & less deep (yet) than my estimation.
With wind I estimated that wind turbines would grow to 8MW with substantial costs decreases. That was too pessimistic. I now estimate that we will see 20MW wind turbines which will produce for ~30% less than the best we haven now. 

It is a matter of good knowledge about the physiscs behind those technologies, and estimate what will happen once real production with real money takes off.

With PV-solar I estimated that thin film may be produced by mills, the same method as paper. However higher yield cells reduced the market volume for thin film. Furthermnore, my estimation that the cost of double junction cells (~30% yield) would decrease faster, showed to be wrong.

With wind turbines, blades are still primitive, more or less copies of plane wings.
With a sudden wind gust the blade should not only be elastic, but also torque (more torque towards the tip of the blade). That allows for lighter blades and higher capacity factors.
It can be done using different fibers in different directions, e.g. Kevlar in one direction and the more elastic Dyneema in another direction. But it involves design and calculation issues that have to be solved.

Robert Bernal's picture
Robert Bernal on Mar 14, 2014

No amount of wind and solar will replace baseload unless pumped storage is developed on the grand scale!

Without meltdown proof nuclear, it comes downs to this: What is the least expensive? Lots of overbuild or lots of storage? Consider also, the efficiency of that storage. Imagine a planetary civilization powered mostly by solar, wind and hydro. Without storage, we would need the inverse of the CF minus overlap from large regional expances. Without the overlap, the storage would have to store about 4x the average consumption (including for about 10 billion electric vehicles), since the capacity factor is only about a quarter of full time baseload. There would always be a little wind blowing – somewhere, so in order to “guarantee” on demand power at all times, we would have to have a massive overbuild (withouit storage). That would be very costly. However, if we chose molten salts (and electrode) coupled with a gas turbine (similar to jet engine such as what is used with NG, today)  we would have to literally double the extra “excess build up” capacity to make up for the 50% loss of efficiency of the turbine. So, we’ll only do that with CSP. Ok, we’ll use pumped hydro which should be about 70% efficient (round trip). But pumped hydro uses FAR more space and demands large “dam” projects, whereas molten salt should be much cheaper. Finally, we could go with the extra expense of batteries in trade for the much higher efficiencies, but I think you get my point. Storage costs more than in just one way!

With nuclear, the meltdown designs would (or should) power the same turbines that are used for the NG back up required by solar and wind (without 24/7 storage). This allows for a GRAND expansion of solar and wind, as the nuclear would replace the coal baseload (we all so obviously rely upon) but only at about HALF the capacity of the rated turbine power max. When renewables power up, excess nuclear (even though just at half of present coal) baseload might have to be used for industrial process heat, such as making clean liquid fuels for industrial equipment (that don’t “like” batteries). Carbon prices would possibly promote this kind of development? When the solar and wind “turns off”, then all you do is add whatever amount of natural gas to the already hot nuke powered turbine. Since alreay hot, there is no loss of efficieny, less CO (and other pollutants associated with cold starts), and of course, less CO2 (because it is burned more efficiently, instantly). 

I imagine we don’t do this now because wind and solar do not present such the variable. But they will when they offer 50% total energy demands! This solar, wind, NG and nuclear option WILL be able to power the 10 billion person strong planetary civilization without any interuption and with very few excess CO2 emission and NO pollution (other than those chemicals from industry, solar, etc and nuclear which MUST be properly contained!

Robert Bernal's picture
Robert Bernal on Mar 14, 2014

I think you are forgetting that more coal has been brought online since the closing of nuclear. Not cool eh?

Bas Gresnigt's picture
Bas Gresnigt on Mar 14, 2014

They burned less coal!
Check the facts.

Bas Gresnigt's picture
Bas Gresnigt on Mar 14, 2014

More advances countries, such as flat Denmark, plan for 100% renewable regarding all energy in ~2050.

In Germany there is debate about increasing the Energiewende target of 80% renewable electricity in 2050 towards 90% or 95% renewable in 2050.

The issue is not whether it can, but whether it can do it against sufficient low price.
The inflexibility of NPP’s make a positive impossible when renewable produce all electricity needed during ~70% of the time. NPP’s cannot compete as they miss the flexibility and low investment of fluidized bed coal plants and gas plants/turbines.

Robert Bernal's picture
Robert Bernal on Mar 16, 2014

If that’s true, then why all this?


And this?

Bas Gresnigt's picture
Bas Gresnigt on Mar 16, 2014

This publication explains the myth.

People forget that more coal plants were closed than opened, and mix (weather) fluctuation with trend.

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