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Smart Grid 19

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BigInch

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Jun 21, 2006
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I started hearing about the "smart grid" and was confused as to why it was supposedly needed.


I must admit that I had no idea that you guys don't know when my power goes off. But actually I find that hard to believe. Surely you must see something; a drop in load, voltage levels increase? Even I can see lower gas flows and higher outlet pressures, even though I may not know what every customer is using, I will have realtime pressure, temperature and flows at gas sources and at the high demand clients. If its true you're operating blind, I can see where a smart grid offers advantages to the grid operators to get hold of some information from critical points in the system, but is it really true you must have access to my home distribution panel?

I suppose every bit counts and raising my thermostat by 1 degree x 1E6 users might enable a peak generator to be switched off, but I have some suspicion that there is more to this than 1 degree. Who knows, it might save me a doller or two, as long as they turn the thermostat on the airconditioner up one degree and the heater down one... and they don't return it to position too early. However I still have some difficulty believing its not the fox guarding the chicken house, or worse, more like the 3 piggies and the wolf... "Come out, come out, or I'll blow your house down!" kinda' thing. I think a "smart-enough" grid can be implementing critical grid point monitoring alone and there isn't really any need at all to monitor my personal energy usage.

An article about smart grid installation in Italy said that 30 million new meters would generate 500 million in revenue, apparently revenue somehow unbilled now, so it was a great incentive. That's 16 Euros/meter and I was billed 75 euros for mine, that's 2.25 billion. Out of 2.75 billion I guess they probably made 1.5 billion on it. So, isn't this just a clever way to get the customer to pay for the network SCADA upgrade by installing things that can be directly billed to the end user and make a few billion in the process, rather than put a few monitors at critical points?

Isn't the personal energy usage manager just a clever add-on to get an excuse to put in a meter that knows when I'm using electricity in my hydroponic basement garden, or can determine if I or the neighbors are bypassing a meter and stealing electricity outright?

It seems if it were really as hot a topic as they say, there would be some chatter about implementing it in this forum already too. So, why so quiet about the smart grid? What's the engineering viewpoint on the smart grid? Most of the things they say are advantages for me can be done with a $10 timer on my hot water heater.

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"The problem isn't finding the solution, its trying to get to the real question." BigInch
 
I did not read everything, but "smart grid" concept keeps being brought up by those who want to sell unnecessary electric meters and signaling systems to those who really do not need it. (residential customers, if they can)

The basic and fundamental flaw is that the residential peak time never coincides with the peak of a grid. When people are getting up in the morning or reaching home in the evening and cooking etc, are off-peak hours. So there is no need to automatically turn of a domestic appliance to help utility meet their demand.

As far as cutting back the usage (energy savings) goes, you do not need smart gizmos that are being pushed.

No wonder there is so quiet about smart grid in real engineering circles.



Rafiq Bulsara
 
And their point about needing a smart grid for switching solar panels to grid when there's a peak doesn't seem to make sense either. Why not just charge batteries, feed to grid during peak hours, or shut off at night. Isn't it so that, due to solar angles and air conditioning loads its pretty much a perfect match anyway?

Speaking about charging batteries, that doesn't even make sense either. Batteries are a pretty expensive way to store electricity. As a domestic consumer, I'd opt for a net-payback w/o batteries as a much more economical system for me, if I had that option. BTW, utilities in Spain have conspired to make net-payback impossible here, so I don't. Anyway, wouldn't batteries for a large utility scale solar installation be prohibitingly expensive to implement that strategy? Wouldn't it be better to VSD some peak gas turbine somewhere, rather than mess around with battery storage? ... even if you're a utility?

There seems to be a lot more advantages for the power company than for me. My biggest load is hot water and I've got that one covered and paid back already. Saved that $10 timer cost during the first month. (The salesman in the hardware store wanted to sell me a $150 timer... Ya really.) The more I think about this smart grid, the less I like it. But maybe we'll all get cheaper electricity out of it. Ya... like that's gonna' happen...not.

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"The problem isn't finding the solution, its trying to get to the real question." BigInch
 
AND

How manageable is a SCADA system with 3 million inputs going to be for Houston, Texas area alone? There is something wrong with this smart grid implementation logic they're dishing up. I'm afraid that this is gonna' be the biggest Trojan horse ever rolled up to the castle gate ... EVER. Its a perfect excuse to take over AOL, MSN, Google ... EVERYBODY. Not that that alone might not be good, but at least I can still say "No" to MSN and internet-TV, but I can't manage to say no to utility power... not yet anyway. When power comes bundled with internet-TV and internet-airconditioning and internet-hot water. WOW! That's it! That's gotta' be what they're really after. Trojan Power!

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"The problem isn't finding the solution, its trying to get to the real question." BigInch
 
Probally a better solution is time of use rates. But the studies typically show the time of use rates don't change most consumer behavior. The industrials will be the group that will change there behaviors the most.

In fact the time of use rate has the biggest effect that I've seen on water pumping applications like irrigation.
 
Believe it or not, 'Smart Grid' is not actually a conspiracy, although there are plenty of companies looking to make a buck off of it.

Benefits of Smart Meters:
- ability to read remotely (cheaper)
- ability to easily disconnect people who don't pay their bills
- prevents certain types of power theft
- makes time of use rates possible/flexible
- allows users to see details of their power usage (via web interfaces, etc)

Smart Meters are not connected to the SCADA system, they are generally fed into a separate MDM (Meter Data Management) system which refreshes much more slowly than SCADA.

Typically, most distribution systems DO peak at about 5pm during peak residential usage, so there's a strong incentive to reduce residential usage at that time through time of use rates and through demand management (those systems where they will control your water heater / air conditioner).

I'm not sure about the comment about switching solar. Mostly solar is left on all the time. It's generally a good source of DG because it follows the system peak fairly well. The only connection between Smart Grid and solar, is that the additional monitoring/sensors in Smart Grid make it easier to manage a lot of DG on a distribution system.
 
OK, maybe not a conspiracy, but I doubt much truth is being sold. And yes, what you say is my point exactly. All major (immediately visible) benefits on your list go to the utility with very little for the consumer, load shifting, which as you say he probably won't do anyway, and more utilization awareness, which is relatively no economic value to the consumer, but the smart grid is being put out there actually sold as a device highy beneficial to the consumer.

Help the consumer do load prioritization is another benefit to the consumer??? S/he already knows s/he runs the laundry when s/he's awake and can take the cloths out and put them in the dryer, hopefully just as the low rate comes in. If they're not doing it already, its probably because there's too much laundry to do between work and low cost times and they can't stay up all night doing it on the cheap. And of course the one's that can afford it, don't care anyway, hence the low importance generally placed on load shifting. And besides, there's really only so much load shifting you can do and still keep your body rythms in sync with a normal life. Don't need smart grid for that.

Irrigation users are already pumping at night. They don't need a smart grid to tell them how.

The only ones that need it are the utilities. It seems they just don't want to pay for it from shareholders dividends.

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"The problem isn't finding the solution, its trying to get to the real question." BigInch
 
rbulsara said:
Residential peak is inconsequential.
I don't know where you get your information, but that isn't true. Our winter morning peaks wouldn't be in the 0500-0700 range if that were true. We've also watched out summer peaks track the growth in residential air conditioning. Residential can make a major difference.
 
I have no hard resources at hand. Just what I gathered over time. I am under the impression that utility grid peaks normally occurs between 11 am and 2 pm, mostly due to industrial and commercial loads. Perhaps utility folks can chime in. Or may be I live in very industrialized area. May be for large regions with little industrialization may have some different profile.

But the fact is that residential billing structure does not include demand charges, means that it does not really matter for managing demand.

Time of use charges are always in place of industrial and commercial users.

Rafiq Bulsara
 
rbulsara wrote:
"There is a reason there is no demand charge in residential billing structure in the USA. Residential peak is inconsequential."

Residential load makes up about 37% of total electrical load (US, 2007), so it's hardly inconsequential, and because of the lack of time-of-use incentives it tends to have a worse load factor than industrials.
The main reason there is no demand charge is not because it's not desirable but because there has never been a way to measure it!

BigInch:
You're right that the utilities will benefit from smart metering. However, there are some theoretical benefits for customers:
- less outages (due to better grid management / faster restoration)
- lower costs due to:
- cheaper meter reads
- less power plants due to load shifting
- less grid equipment (being run closer to limits)

Of course, whether the customer will ever see any of the cost savings is a big question!

You're also right that much of the benefits of load shifting can be done without actual smart meters as long as the meters can measure on and off peak usage. Interestingly, residential meters in North America have never had that capability.
 
redfurry:
What stops utility companies to install demand reading meters for so many years?

People promoting (or talking about it in vain) residential smart meters etc, are assuming that the present utility system operators are dumb!

Smart and remote monitoring and data logging where it matters and justifiable is already in place. Even my water meter is read by wireless technology by my water supply corporation. But it is not intended to turn off my water supply when needed.

Rafiq Bulsara
 
Rerouting during outages? 99.995% reliability and 2 hours down per year is good enough for me. I'd even bet smart meters won't change those numbers. If somebody would come close to guaranteing that the cost would go down when smart meters are in place, that would be a sales pitch I could go along with, but nobody ever mentions it.

Isn't the real answer, better insulation? I'll bet that would save the consumer about 20% and the utility another whole power station, but then again insulation and not building power stations isn't their profit generator now is it.

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"The problem isn't finding the solution, its trying to get to the real question." BigInch
 
BigInch…FYI…

Some utilities actually have financial incentives for allowing the installation of load management systems in residential homes. LMS transceivers are provided by the utility and are installed in homes to enable the distribution dispatchers to reduce overall load at peak times by actually turning off certain feeds in your home. This is done be sending an encoded signal in the distribution lines from outbound modulating units located within distribution substations. Obviously the user has to volunteer and comply with the changes in their overall power consumption “profile”.

This has been around for a while, prior to the term “SmartGrid” being coined, and could be considered a “Smart Grid” technology. However, I believe you’re really just hung up on the political ramifications of such terminology. New power system technologies across the board can, if implemented correctly, reduce costs for everyone involved. Whether it is being hyped up and funded correctly by politicians is another subject.
 
The installation of "smart meters" is also forward looking for the time when electric cars are more numerous. The power saved in the batteries of those electric cars could be used to supply peak demand.
 
Let me get this straight. I pay for batteries to go in my car so I can drive it to work and at 2-4pm the utility not only uses my storage capacity, but my electricity too and ... I take a cab home and to work the next morning. Don't think I like that one either.

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"The problem isn't finding the solution, its trying to get to the real question." BigInch
 
But if we do not have electric cars there would be no burden on electric grid! How would a battery in my car or home going to supply peak demand of the grid? Other than adding to the demand when charging it.




Rafiq Bulsara
 
Power companies are no longer run by engineers. Accountants, lawyers, and Women's Studies grads are now in charge. That explains why the Smart Grid is so exciting to everyone except those of us who still know what the hell is going on.
 
Charge the battery fully at night at the lowest rates of the day, drive to work in the morning and top it off at somewhat higher rates. Let the utility buy back some of that capacity in the middle of the afternoon, but still leaving enough charge for the commute home, they pay for the power at peak rates, then start the cycle over again.

Some places the disparity between on peak and off peak, coupled with the must run generation, results in the wholesale electric market going negative in the middle of the night. When that happens, you could get paid to charge the batteries at night and then get paid to return some of that back to the system during the day. Sounds like a win-win.
 
What happens when you forget to unplug you car in the morning?
Or what happens if you forget to plug in your car at night?

Still the plug in car thing sounds bad.

And would it not take additional electronics to handle the conversion from DC to AC, then just being able to handle AC to DC (a diode and capacitor comes to mind).

Fix the problem with turning off your hot water heater, by switching to gas hot water.

 
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