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Comment: your imagination isn't working well :) (Score 1) 260

by stomv (#47858673) Attached to: Tesla Plans To Power Its Gigafactory With Renewables Alone

In Nevada and California, electric power is needed most -- and is most expensive -- during hot daytime hours. This is true throughout most of the country, and won't change until there are metric library of congress tonnes of it throughout the grid. Someday, with oodles of PV, the peak will shift a few hours later in the day, to just after sundown (on hot weekdays).

Note: there are some parts of the country, notably the deep southeast, that are winter peaking. Winter peaks tend to be weekdays at around 6-7am.

Comment: Storage isn't valuable right now (Score 5, Informative) 245

by stomv (#47802925) Attached to: Power Grids: The Huge Battery Market You Never Knew Existed

Pumped storage ... needs specific geography, high and low reservoirs close to each other to reduce losses pumping water uphill over long distances. It also needs a guaranteed supply of water, lots of it and the sunny parts of the US where large amounts of solar power are being generated are distinctly lacking in water

One only needs a low reservoir (see the Taum Sauk). Furthermore, while pumped storage certainly isn't a good idea in the Southwest, it is ideal in the Great Lakes area, where there's tons of wind resources (see: Iowa, Minnesota, etc.). And, as it turns out, there is a (functionally) infinite supply of water in Lake Michigan and a functionally infinite amount of land with delta h on the West Coast of Michigan, which has hills immediately adjacent to the Lake due to thousands of years of wind blowing from Wisconsin to Michigan. A storage plant like this already exists, just south of Ludington MI. We could easily build 100 GW worth of pumped storage there, equal to the capacity of all nuclear power in the US.

Pumped storage is also lossy, typically about 65% efficient round-trip.

My experience is that the average is closer to 75%, and it can be as high as 90% with modern, well maintained pumped storage. Pumped storage also has extremely fast ramping capabilities, making it very useful for the minute-by-minute operation of the grid. Of course pumped storage, like all major power plants, requires transmission investment to be fully useful.

Grid gas, coal and nuclear generators don't need storage as they either run flat out to meet the instantaneous demand and they can throttle back in quieter times.

Nuclear, coal, and gas steam plants have very real operational limitations. Nuclear is almost never ramped back to follow load; it's cheaper in the long run to pay negative locational marginal prices (LMPs) if need be. Coal and gas steam can only ramp a few MW per minute, and have minimum outputs whereby they can't maintain power any lower -- and that's often at about 50% of capacity. At that point, any lower output requires a shut down, and then a 12-30 hour cool down whereby the unit can't be restarted. Nuclear, coal, and gas steam are extremely inflexible generators relative to hydro, gas/oil CT, and even gas CC.

At the moment intermittent wind and solar generators use the grid as free storage but the more intermittent power that is added to the generating mix the more that storage will be needed to deal with peak inputs and debits.

Free storage? Wind and solar fueled generators, like all generators, sell the energy instantaneously. Your metaphor makes no sense. All operating power plants sell in real-time. Same price for the same power. Eventually, substantially more storage will have economic value, but on the mainland US grid, not for a long time. California is poised to have 33% renewables by 2020, and they don't need additional storage. (There's an order for ~1.5 GW of storage to be procured, but it's not needed -- it's CA's way of pushing progress forward, seeing that eventually storage will be a less expensive resource (LCOE) than CTs.) Most other parts of the mainland won't have exceeded 10% non-dispatchable renewables by then.

Getting wind and solar farm operators to pay for this extra storage probably isn't going to happen, sadly.

Why should they? In most of tUSA, there's a day ahead and a real time market. Power has a price (LMP). Generators can sell into that market or not. When supply exceeds demand, the LMP goes negative, and all generators who are operating are equally responsible for the problem; all generators who are operating at those times pay the same financial penalty. That includes operating wind and solar and the nuclear and gas and coal that can't turn down.

In the mean time, the number of MWh that are curtailed is a tiny, tiny fraction of the total MWh consumed in America. Storage simply isn't very valuable on the American grid right now because we don't have very much in the way of inflexible generation -- about 20% of the GWh of nuclear, and under 10% of inflexible renewables. It will be many years (more than a decade) before the percent of electricity we have to "throw away" due to inflexibility exceeds 2%, and to the extent that coal plants continue to retire and load continues to grow, that year will be pushed farther and farther into the future.

Storage is interesting tech, but it's simply not necessary for the American grid to operate reliably or economically anytime soon.

Comment: Erm, not so much. (Score 4, Informative) 142

by stomv (#47685887) Attached to: Delays For SC Nuclear Plant Put Pressure On the Industry

First of all, nuclear power plants are far more complex than coal plants. Sure, the steam to electric part is identical, but controlling a nuclear reaction requires far different parts than crushing and burning coal.

Secondly, coal fired power plants are not "popping up everywhere" in America. No new coal plants will be built anytime soon, because 111(b) prevents new sources of electric generation that emit more than ~1200 lbs CO2 per MWh (coal is ~2000 lbs). A few plants have opened in the past five years; we won't see any more.

Thirdly, it isn't "red tape" that caused this latest delay -- it's the inability for suppliers of key components of the power plant to deliver the materials on time. The parts are specialized, the vendors capable of building (some of) those parts few and far between, and the list of parts that must be assembled in order rather long. Any delay ripples through the project, and the loan (plus interest) needs to get paid back, even if the plant isn't operating yet.

The big risk in nuclear construction is a financial risk. It isn't until much later that the nuclear reaction itself becomes a challenge.

Comment: You started so well, then went downhill (Score 0) 710

by stomv (#47455515) Attached to: People Who Claim To Worry About Climate Change Don't Cut Energy Use

In terms of criteria air pollutants (CO, NOx, SO2, PM2.5, PM10), it's certainly true that modern cars are cleaner, even an F150. But that 150 gets 12 mpg, less than half of the U.S. average mpg for new cars. Since climate change is a thing, since automobiles are collectively a significant emitter of CO2, and since the F150 emits twice the CO2 per miles as an average new car, and since those average new cars also emit small amounts of those criteria air pollutants, no a 2011 F150 is not a green car.

Then you just slip into some strange piece of climate change denier and anti-tax zealot. There's no question that the impacts of climate change are systemic, pervasive, and real. Parts of Miami and Norfolk VA are under water during high tide. Hell, there are island nations preparing to no longer exist. Somehow, these "local" disasters are hand-waved, along with the hurricanes, droughts, floods, etc. But you call high gas taxes ruinous for the economy and claim that they have no impact on the environment, despite the facts that (a) most Western European nations have high gas prices, (b) most have higher mpg fleet averages, and (c) most have economies that are functioning just fine.

We get it. Regardless of your actual age, you behave like the old Brits referenced in the summary. That doesn't warrant a 5: interesting, except that it's interesting that old British-type dudes who are entirely wrong on the science and implications of climate change (and foolish about tax policy) are on slashdot.

Comment: Re:Nuclear power loses? (Score 1) 268

by stomv (#47285927) Attached to: The EPA Carbon Plan: Coal Loses, But Who Wins?

Indeed. Existing nuclear wins because the metric EPA is using for compliance includes a portion of MWh generated by existing nuclear in the denominator (something like 5%). Therefore, keeping existing nuclear online will help states comply with 111(d). Existing nuclear is a winner under 111(d) -- including the nuclear units under construction in GA, SC, and TN.

New nuclear? New nuclear will never win. It's simply can't hold a candle to PV and wind in an unsubsidized market. New wind is cheap enough now, and new PV trending that way that it's not worth the tremendous risk associated with a long, large, non-scalable, expensive construction project.

Comment: Re:Big Oil wins (Score 2) 268

by stomv (#47285899) Attached to: The EPA Carbon Plan: Coal Loses, But Who Wins?

If your bills are going up 50%, its because your electric company is spending lots of money on existing coal plants so they emit less SO2, NOx, PM, and Hg. Of course, they'll emit about the same amount of CO2. Utilities that haven't insisted on coal coal coal haven't seen substantial increases in rates.

This is a generality -- individual utilities may have rate increases for other reasons, but very, very few utilities have had rates go up by 50% within the past 3 years. In fact, many utilities have had rate decreases.

Comment: Peak? (Score 3, Interesting) 268

by stomv (#47285869) Attached to: The EPA Carbon Plan: Coal Loses, But Who Wins?

Peak demand isn't as close to daylight as you might expect in the South. In fact, many systems are winter peaking (central Florida and Appalachia come to mind). Those systems peak winter 7-10am. Sure, the sun is just starting to come up, but PV isn't going to have a significant impact on that peak. Similarly, peak is 3-6pm. PV produces it's best power at high noon. As more PV comes on the system, the "net"-peak will push to 4-7pm, then 5-8pm. Again, solar contributes to meeting some of that peak, but depending on geography it isn't always going to align as well as you might think, including in the south.

Comment: For fuck's sake, how does this get a 5, Insightful (Score 3, Informative) 268

by stomv (#47285813) Attached to: The EPA Carbon Plan: Coal Loses, But Who Wins?

> I think you can be sure no matter how this plays out, power is going to be more expensive.

No, you can't be sure of that. Wind power in the central portion of the country is cheaper than coal now. PV is cheaper than market power in the Southwest and the Northeast now. Many coal plants in tUSA are 50+ years old -- they're going to retire soon one way or another. And, not for nothing, wholesale electric power is cheaper now than it was five years ago due to cheap natural gas (and, by the way, switching from coal to gas helps comply with 111(d) and saves money).

> if the coal-fired plants are removed from the equation before replacement sources of power are in place, there will be power shortage

If my aunt had nuts, she'd be my uncle. There's absolutely no chance that 111(d) will result in reliability performance below the industry standard 1-day-in-10-years. Just won't happen. Retiring a unit requires years of planning. Google "integrated resource plan IRP" for your favorite utility and hunker down to a ~120 page report, produced every 3-5 years, laying out the company's plan, including projected retirements, new units, new transmission, etc.

111(d) doesn't require any coal plants to retire. It requires our fraction of electricity generated from coal to be reduced. The coal plants can still be "plugged in" and operated during times of peak load (weekday summer afternoons and winter mornings); what they can't do is operate much the rest of the time. Instead, a combination of new energy efficiency measures, new renewable energy production, more frequent operating of combined cycle natural gas generators, and squeezing even more MWh out of existing nuclear units through uprates or reduced downtimes will be the way states will comply with 111(d).

Seriously slashdot. Pithy remarks more frequently display ignorance than insightfulness.

Comment: Not your business? (Score 1) 932

by stomv (#47216423) Attached to: House Majority Leader Defeated In Primary

As a Virginian (and now as a Marylander), I don't consider it any of my business who represents people in say, California.

This is asinine. The 100 US Senators and 435 members of the US House each have an equal vote in their respective chambers on all federal legislation. So long as you as a Virginian (and now as a Marylander) are subject to federal law, then each and every of those Congressmen have a direct vote on the laws that you are obligated to follow. Just because only 2 of the 100 US Senators will return your call doesn't mean that the other 98 aren't your business. They are United States senators, not California state senators. They write your laws; they're your business.

Comment: Re:As a pedestrian (Score 1) 490

Indeed. The article agrees with you -- it doesn't advocate for "blasting" through the light. It advocates for approaching the stop sign controlled intersection slowly enough to determine all cross-traffic location and speed to determine if it is safe to cross, and then doing so. That includes peds as cross-traffic. Further, it advocates coming to a stop at traffic light controlled red lights, determining all cross-traffic location and speeds, and then, once there's no risk of collision, proceeding.

For both stop signs and red lights, the Idaho stop advocates for pedestrian safety, not for "blasting through the red lights".

I fail to see why you didn't RTFA.

Asynchronous inputs are at the root of our race problems. -- D. Winker and F. Prosser

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