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#21

My random block of Lewisville didn’t lose power save for a 15-minute outage early on. Explanation from TNMP was extremely limited ability to rotate outages while maintaining grid stability so they shut off other blocks on a ~90% duty cycle. A friend ~1/2 mile away suggested I find out which politician that lived in my block and offer them a gift basket.

Don’t think they have that ability - their main focus is automating billing so as to eliminate meter readers and bill residential customers for suboptimal power factor despite having already installed PFC equipment at residential substations.

Demand dispatch at the major-appliance level seems to be the approach that utilities are experimenting with.

#22

Yes… switches on major appliances would be even better, but even shutting off entire houses would be better than the sledgehammer approach they take now.
I’m pretty sure they can turn your power on and off for nonpayment without someone showing up personally to do it… anyone know for sure?

#23

That’s the most Texas response to the most Texas thing ever. They should just setup their own grid then! :rofl:

I’m not aware of this. Was it covered by the press? Data to compare outages? I’m not saying there weren’t any shenanigans, just that if there were I haven’t read about them.

#24

https://www.prestonhollowpeople.com/2021/02/16/yes-highland-park-is-experiencing-outages-too/

I think one of the misleading things here is that some girl drove around with a phone and took video of houses with lights on, and folks in Highland Park had lights on - likely for the same reason that tens of thousands of other did - they had generators.

When you’ve got a $1.5M home, the incremental $7,500 to add a generator is a drop in the bucket. And since there is minimal utility trenching in HP and the surrounding areas, they’re used to losing power because of ice storms and wind storms and the like.

Hell, that’s the reason I have a generator.

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#25

I think I was in that block and it was more like a total of 2 hours of power from Monday 2am until Wednesday 9am. Brrrr…

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#26

Can’t find specifics on the smart meter TNMP installed several years ago, however the Plus version of the same meter claims an optional integrated, factory-installed remote disconnect switch to help utilities efficiently address non-payments and move-in, move-outs, suggesting that the likely older, vanilla, non-plus version may well lack this feature.

#27

This only affects people who are buying their power at wholesale pricing. My utility company (Grayson Collin Electric Co-op) stated on their Twitter feed:

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#28

I got a similar email from TXU. ONCOR with its meter charge and taxes are typically half my bill anyway.

I was very fortunate, never lost power for a moment (East Arlington, just off 360 at Park Row). Beginning two streets away to North it was out for quite a ways for at least a mile and a half. Can’t say for how long, because I didn’t go out for three days after that.

#29

Almost. But, not quite. Those of us who signed up for wholesale rates did so with the understanding that the rates were 100% market driven. And, yes, they could vary from less than 0 to $9.00.

What we did not sign up for is sudden minimum price controls mandated by the PUC. Personally, I would have been happy to pay (high) market prices this week due to past cost savings. However, the $9 government price control was in effect for much longer than any market driven spike. This was purposeful and very clearly stated in the PUC’s announcement last Monday. The market rate at the height of the cold was well under $9.

When the price controls were lifted at 9am on Friday morning, the rate suddenly changed from $9 to 4 cents within 5 minutes.

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#30

I believe the scenario you are describing is “islanding” your local power grid. Apparently there are issues with doing so though, such as your local island is sure to drift off the 60 HZ AC timing of the entire system and it’s very hard to sync back up. Hence, if you go the Island route it’s impossible to send or receive power from other sources until you have everything realigned. TLDR: You are on your own and it’s really hard to rejoin the pack.

I read somewhere the ERCOT manual goes into this topic, and many others, but is quite a hefty read.

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#31

I have some personal experience on a very, very small scale with this - a pair of MEP-816A generators.

In theory, you had a signal cable that went between the pair, and you’d plug it in, then start 1, then start 2, then balance them using the voltage and frequency controls independently (and get them as close to one another as possible, then close the interrupter on 1, then put them into sync, then stand back and be sure the sync lights are blinking in unison, then you could close the interrupter on 2 and in theory you were synched and making nice 60 Hz power and you could close the load.

That was the theory.

In practice, that shit never worked right, and if you didn’t give them their proper care and feeding and sacrifice, they’d drift out of sync, and that’d trip the protection circuits, and power would stop flowing to the people who wanted it. Inevitable as I was sleeping somewhere.

Keeping multiple generation sources in sync with one another is a non-trivial challenge. Even to this day, frequency drift is the greatest danger to any given grid, and it’s what they watch more closely than anything else. Look at this from ERCOT’s site:

http://www.ercot.com/content/cdr/html/real_time_system_conditions.html

They track frequency down to 1/1,000 of a Hz, in a system generating 36 gigawatts of power.

All that said, you can connect with other power sources via what’s called a DC Tie, but that means that AC comes in from both sides, is rectified to DC for the exchange, and then inverted back to AC again.

But at a huge current - 375 kVa AC side.

It’s not the most efficient system, but it’s the only way to do it.

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#32

The Honda EU2000 generators generate AC, convert it to DC and then back to very clean AC. A Companion model can be used stand alone or in parallel with a Standard model. A special jumper adapter is required and connects DC to DC to solve the sync issue.

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#33

That’s how all the inverter generators work. It’s pretty clever. I was surprised to find out they’re 200+ volts from the stator. I figured they’d be 12 volts but they were abble to ditch a bunch of baggage by rethinking it from scratch.

#34

I own one of those nifty Hondas (because of how quiet it is), and I’m sure they do a reasonable job of staying in sync.

The generators I was referring to are 60 kW each, and were (IIRC) a John Deere 6 cylinder turbodiesel.

The motor and generator assembly weren’t generally the issue (other than being an unholy PITA to change the oil), it was keeping the pair in sync that was impossible. The pair that I had to keep running just never liked each other very much, and would drift out of phase regularly, but not at any defined interval other than a weather change.

#35

Do you know if the gensets did any active load sharing between them?

#36

When I bought my Hondas in 2010, I don’t recall knowing about many other options. A search for reviews of portable generators now shows there is a mini industry providing an incredible variety of portable inverter generators including some that claim to be quieter than Honda.

If you have a natural gas furnace and lose power, a 2,000 watt generator can easily power the ~600 watt blower motor and control system as well as some lights, a laptop and internet router.

It is widely recommended that to power electronic devices, an inverter generator must be used. The “open frame” generators are much cheaper but power is not as clean.

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#37

I gather there are some options in the “open frame generator” space with THD <5% which might suffice for many electronics for markedly less than a comparable-wattage inverter generator (ex - Generac: model page | spec sheet). Still have the noise and constant-RPM fuel consumption issues.

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#38

@ESmith, I totally agree. My brother is looking to buy a generator so I’ve been looking around fir him. Its interesting that the two categories discussed are inverter and open frame. The assumption of a number of articles that I have read is that open frame means non inverter and a high THD. Clearly there is no reason that an open frame cannot be inverter and/or low THD. Seems like it would be better to call them inverter or non-inverter.

#39

The MEP-816A’s?

Yes, they load shared. You could pick what you wanted, voltage-wise, and they would share the load between them. It’s why keeping them in near-perfect sync was so important, because if they fell out of sync (and the safeties were operational, which was no guarantee), the bravo unit would shut down generation capacity and you’d lose half your available power, which if they were under real load, meant the pair both went down and then no one had any juice.

#40

I’ve collected the few ≤5% THD open-frame models I could find in the generator spreadsheet I put together in the Generator Advice thread (filter Type field for “Professional”). I’ve found that most open-frame models don’t specify THD, a good many specify THD well over 5%, and that only a small minority are ≤5% They all look dreadfully inefficient at anything less than near-full load but do offer more kW than inverter models, and in my cursory price research are cheaper per kW.

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