Tuesday, February 24, 2015

The Local Grid: Pictures at the Edge

It's minus 24 at my house this morning, and here are some pix I snapped of the ISO-NE Real-Time system page.

To me, the first one is the most telling: 20,000 MW demand, 243 MW in reserve.  That's too little reserve!

The rest are more typical winter ISO.

Grid running at over $200/MWh.

Actually, it has been bouncing up to over $300/MWh, in the five-minute market.  I just didn't get a screen shot at the higher levels.

And here's the fuel mix: Lots of coal and oil, of course: total of 27%.  Renewables hanging in at 6%.

And the renewables chart. Wind is actually a reasonable part of it, since this has been windy weather.  Wood and refuse dominate, of course.  Of course, what is "reasonable"?  Wind is 17% of 6% on a day the grid  is struggling.

Our summer peak is above 20,000 MW, and today is only 19,000.  However, in the summer, you can get natural gas to the gas-fired plants.


Rod Adams said...

Wonder how much demand has been destroyed with those high prices? Does the grid have many customers that pay prices linked to spot market or are they mostly insulated by regulated distribution utilities?

These are musings for me or someone else to consider, not a request for research efforts.

Meredith Angwin said...


Thanks for the comment. Indeed, most customers are insulated by distribution utilities, but if the regulated distribution utilities are paying a lot for power, this will be reflected in what they bill customers. ("Look at these prices! We need a rate increase." "You're right. Here's your increase.")

So it matters whether or not the distribution utilities have lots of fixed-price contracts with generators, few fixed-price contracts with generators, market-follow contracts with generators, etc. As I understand it, most utilities buy some of their power on the spot market, because who can predict exactly how much power they will need? Utilities need flexibility, so they often choose to under-contract and buy "the rest" on the spot market or in very short-term power purchase agreements.

Also, in deregulated states, there seem to be rules on how municipalities can purchase power versus how free-lance consolidators can purchase power. I admit I don't have much of a handle on this.

In short, these prices do get reflected in consumer prices, but the story is complicated.

Rick Maltese said...

Recently I asked a more knowledgeable person to explain spot pricing. Here was their answer:

"The futures markets attempt to predict demand and procure energy production to meet it. The regulation spot markets provide regional and local energy as needed to meet overall demand and maintain stability as necessary. If there are significant errors in predictions, such as during last winter's polar vortex, the immediate market price can skyrocket in locations where energy transport in congested. This holds true for most forms of energy I am aware of.

Natural gas and electricity are tightly coupled because of the nature of storage of each. You should read up on how we deal with seasonal variability through natural gas storage. We actually pump NG back in the ground during the summer and pump it generally from the Midwest to the east and west coasts during the cold seasons. Technically it's even of larger capacity than pumped hydro, but pumped hydro is cycled far more."

jimwg said...


I know this is riduclously off-topic but I want to tap your keen as a physical chemist. As we know there's a HUGH gap between the energy chemicals can store and furnish and nuclear reactions in orders of millions I gather. Please go wild imagining how there could be an "in-between" energy potential source; not quite nuclear but vastly beyond current chemistry. I mention this because I'm unsure whether it was a dream or a time-blurred memory fragment, but I think Walter Cronkite said that the "Cold Fusion" controvery then would've "filled-in" the energy gap between nuclear and chemical with all the practical apps that'd offer. What say you, and if were you a "God", how would you envisage the neccessary make-up of such an energy source?


James Greenidge
Queens NY

Meredith Angwin said...


Yes, they do store up natural gas in underground caverns during the summer, and put the gas in the pipelines when the weather gets cold. With cold weather, there's more demand and higher prices: a win-win for the gas producers.

There's a tendency to say: "Hey, these temporary high gas prices don't mean much…just a bit of congestion in the system in cold weather." However, the overall price on the grid IS affected by these rises. Vermont Yankee had to "revenue share" with the local utilities when the grid price went above 6.1 cents per kWh. Last year, VY shared almost $18 million! It had these sort-of-excess profits through high prices on the grid, even though the overall Henry Hub price of natural gas remained low.

You pose a very interesting question. I think there could be something between nuclear and chemical. Nuclear will always liberate millions of times more energy per atom than chemical energy can provide. But if there were some type of nuclear that was intrinsically slow reacting, controlled by internal kinetics rather than controlled by people, it could be liberate in-between amounts of energy, per pound of starting material. Not per atom, but per pound of "fuel."

To some extent our light-water reactors are already this way. Only the (approximately) 5% of the rod that is U-235 reacts…the 238 just sits there, eating an occasional neutron to turn itself into plutonium which can also react. So we have in-between amounts already, in some sense, because only the U-235 and some of the 238 will react.

This has certainly given me something to think about! Good question and I hope some other people weigh in on it.

Anonymous said...

It would have to be a completely new kind of physics in the sense of the fundamental energy release. Nuclear forces are just so much stronger than the electromagnetic forces of chemical bonds. It's hard to imagine an in-between process. Even the weakest of nuclear transitions, things like low-energy beta particles from tritium, for example, are orders of magnitude higher in energy release than the most energetic chemical reactions. The deuteron is just barely stable, but still the binding energy is in the MeV range.

jimwg said...

Okay, I'm going to reveal my Chem 101 ignaorance here but please tolerate my analogies: A diamond is so tough because the carbon bonds are so super-tight, right? Were those bonds released somehow, would the kinetic energy be far above those of say, gasoline? If so, could it possible to produce (just a working term not literal) "gasoline" or "coal" with the chemical binding energy of a diamond and somehow, maybe via a catalyst? release that energy at the other end? Can one force or construct (maybe via reactors?) such super-hard powerful chemical bonds in substances? Can you even surpass a diamond's chemical "binding energy" with whole new substances?

James Greenidge
Queens NY

Meredith Angwin said...


You ask another good question! But as anon says above, the difference in energy released in any nuclear-based reaction (radioactive decay, nuclear fission, nuclear fusion) is far above the energy released in a chemical reaction. That is not likely to change.

Diamonds are indeed the most tightly bond of carbon containing compounds, but if you look at the Graphite-to-Diamond section in this website, you will see that burning carbon (graphite) releases 393kJ/mole, while the transition to diamond is less than 2 kJ/mole. So a stronger chemical bond can't affect the heat release very much.

There is basically, nothing like nuclear energy.


Engineer-Poet said...

Next Big Future has an article on ultra-high energy electronic bonds, but raising the energy levels of a single atom by 100 times and doing the same to a bulk storage material are two very different things.