Transmission system metering

[kartracer087]

So I'm think this is somewhat of a complicated question.

In a transmission system you have the generation and the end users (loads). So am I correct in thinking there is sort of a three tier system in handling generation revenue?

Basically what I'm thinking is it works like : Generation company produces power. Transmission operator sees a bill for export kw from the producer. Then the transmission operator has meters at the handoff to the local utilities at the connection to the bulk system. The bulk system operator and through laws and master agreements, then has to take the incoming revenue from coming in from the utility load users and then it gets split per agreed price to the various producers. Is this an accurate very basic understanding of the revenue stream effectively? Also, one other element is export to other grid operators. Whatever is exported to other grids is also incoming revenue to be distributed to the producers. Producers earn based on how much they actually produced.

Let me know if my crude interpretation is accurate..

Thanks

 

[sushilksk]

Transmission operator can bill for enery transfer kwH to Distributor. Ultimatley all revenue comes from distribution.

There should be a fixed part, independent of actual energy produced.

 

[waross]

It depends. Any scheme that you can imagine is probably used somewhere.
Here is an actual, one month power bill for a single house.
Everything is charged separately.

Invoice Charge Details
Charge Description Period Quantity Unit Basis Rate Amount
Transmission Charge Demand Charge (Kva) 2021/08/04 - 2021/08/31 140.00 Kilovolt Ampere Demand 0.163600 $22.90
Transmission Charge Demand Charge (Kva) 2021/09/01 - 2021/09/01 5.00 Kilovolt Ampere Demand 0.163600 $0.82
Transmission Charge Energy Charge 2021/08/04 - 2021/08/31 313.00 Kilowatt Hour Energy 0.005500 $1.72
Transmission Charge Energy Charge 2021/09/01 - 2021/09/01 11.00 Kilowatt Hour Energy 0.005500 $0.06
Transmission Riders Rider G - Temporary
Adjustment
2021/08/04 - 2021/08/31 313.00 Kilowatt Hour Energy 0.000170 $0.05
Transmission Riders Rider G - Temporary
Adjustment
2021/09/01 - 2021/09/01 11.00 Kilowatt Hour Energy 0.000170 $0.00
Transmission Riders Rider S - Sas
Adjustment Rider
2021/08/04 - 2021/08/31 313.00 Kilowatt Hour Energy 0.003580 $1.12
Transmission Riders Rider S - Sas
Adjustment Rider
2021/09/01 - 2021/09/01 11.00 Kilowatt Hour Energy 0.003580 $0.04
Distribution Charge Customer Charge 2021/08/04 - 2021/08/31 28.00 Flat Fee Fixed 0.025600 $0.72
Distribution Charge Customer Charge 2021/08/04 - 2021/08/31 28.00 Flat Fee Fixed 0.297900 $8.34
Distribution Charge Customer Charge 2021/09/01 - 2021/09/01 1.00 Flat Fee Fixed 0.025600 $0.03
Distribution Charge Customer Charge 2021/09/01 - 2021/09/01 1.00 Flat Fee Fixed 0.297900 $0.30
Distribution Charge Demand Charge (Kva) 2021/08/04 - 2021/08/31 140.00 Kilovolt Ampere Demand 0.053500 $7.49
Distribution Charge Demand Charge (Kva) 2021/09/01 - 2021/09/01 5.00 Kilovolt Ampere Demand 0.053500 $0.27
REA Charge Association Levy
Customer Charge
2021/08/04 - 2021/08/31 28.00 Flat Fee Fixed 0.170000 $4.76
REA Charge Association Levy
Customer Charge
2021/09/01 - 2021/09/01 1.00 Flat Fee Fixed 0.170000 $0.17
REA Charge Rea Deposit Reserve
Demand Charge
2021/08/04 - 2021/08/31 28.00 Flat Fee Fixed 1.447000 $40.52
REA Charge Rea Deposit Reserve
Demand Charge
2021/09/01 - 2021/09/01 1.00 Flat Fee Fixed 1.447000 $1.45
REA Charge Rea O&M Customer
Charge
2021/08/04 - 2021/08/31 28.00 Flat Fee Fixed 0.140000 $3.92
REA Charge Rea O&M Customer
Charge
2021/09/01 - 2021/09/01 1.00 Flat Fee Fixed 0.140000 $0.14
Balancing Pool Charge Rider B - Balancing
Pool Adjustment
2021/08/04 - 2021/08/31 313.00 Kilowatt Hour Energy 0.002450 $0.77
Balancing Pool Charge Rider B - Balancing
Pool Adjustment
2021/09/01 - 2021/09/01 11.00 Kilowatt Hour Energy 0.002450 $0.03
Energy Charge Energy 2021/08/04 - 2021/08/31 313.00 Kilowatt Hour Energy 0.061500 $19.25
Energy Charge Energy 2021/09/01 - 2021/09/01 11.00 Kilowatt Hour Energy 0.061500 $0.68
Admin Charge Administration Fee 2021/09/09 $7.50

In other cases, one company may own the entire system from generation to final distribution.
Their bills may be for consumption only, or a fixed charge plus a charge for consumption.
I have seen instances where a power plant produced and was paid for mainly KVARs.
A power producer may be paid a base rate plus a peaking rate.
A swing set operator may be on a different rate than base load producers.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[FacEngrPE]

In a Market area like PJM I do not think you can talk about transmission billing generation, etc exactly, as everyone Generation, Storage, Transmission, Distribution, end even some larger end users buy and sell directly in the market. PJMSettelment (the market agent) issues the bills and handles settlement for market transactions.

Depending on the local law "retail" end users may be somewhat decoupled from the market depending on the authority having jurisdiction's approach to regulating prices.

Every market will have governing documents which explain their tariff's similar to these - PJM Governing Documents. Following the costs using these documents will result in a very complex relationship chart.

PJM market has slots for:
[ul]
[li]Energy[/li]
[li]Capacity[/li]
[li]Various kinds of reserves,[/li]
[li]Demand response.[/li]
[/ul]

ERCOT (Texas) market has a slot for
[ul]
[li]Energy[/li]
[/ul]

These markets achieve different results, which hopefully match the goals of their regions.

 

[kartracer087]

Thanks for the input. Yes I know it can be very complicated in breaking out billing but as far as metered points at each handoff is where I see the actual billing being generated from. Because the generators are connected to a mass grid, effectively in a simple manner you have to pay for bulk generation ultimately by taking the metered load. Like ComEd would have to pay an entity like PJM or it's generation companies for whatever flows from PJM system into ComEds system less any generation directly by ComEd.

 

[Palletjack]

Producers meter outgoing at the generation point.

Transmission operators use “compensated metering” to cover for for line losses on the transmission lines when the delivery points are metered at the delivery ends as most are.
Most meter at the head end also to verify line losses. Metering is cheap..
Finally distribution company absorbs line, XF, and other losses in rates.

 

[davidbeach]

Metered at every interchange point. The particular market determines what any particular value means. An answer that is correct under one set of conditions may be wildly inaccurate under other conditions.

I’ll see your silver lining and raise you two black clouds. - Protection Operations

 

[kartracer087]

Makes sense. Attached is a very high level overview of what I interpret as being a very rough idea of how it works. Basically by metering at each exchange point as mentioned then it is possible to develop working conditions of the grid to confirm operational compliance and that the terms of selling or buying are maintained. Effectively that was what my question was aimed at is how you can back up agreements made due to system operation. I don't think you can just arbitrarily establish a contract without having empirical data that shows, yes in fact, you are owed for what you produced and you must pay per agreements what you took from the grid. My rough example establishes a pathway where the **directionally compensated** metering would easily show power flows wherever there exists an exchange involving monetary agreements.

 

[FacEngrPE]

kartracer087 There are as many answers to your question as there are power markets, probably more.
PJM Governing Documents explain how PJM handles inter party settlement, and every other revenue related situation, including long term growth management. If you dig around you will find spreadsheets explaining how some of the rates are developed. This sort of stuff puts engineers to sleep from boredom, and keeps accountants up at night.

 

[davidbeach]

Then there are the 40+ year old "contracts" that exist in the memory of those that keep alive the handshakes that their predecessors told them about. Both parties are willing to accept the outcome, but neither can provide a document to justify "what we've always done". Trying to touch one of those can be a career limiting move.

I’ll see your silver lining and raise you two black clouds. - Protection Operations

 

[kartracer087]

Sounds like a big mess to me the more I think about it. I wonder how things got this messy perhaps it was the concept of connecting all generators together in this big grid may have made the system more stable but created another monster in how to handle the revenue end of it. It sounds a bit like too many cooks in the kitchen type of thing. Would be easier if there was some kind of restriction in the topology structure but these days with consumers also able to generate it gets very messy.. It kind of shoots any sort of logical topological relationship to heck. As an engineer these kinds of things make you just think "why did this have to be so sloppy like this, there is a better way"... But I think once you bring money into the equation it becomes a tireless mess.

 

[FacEngrPE]

Before deregulation forced utilities to act like their generation and distribution divisions, and they owned the transmission between, the revenue to cost was figured out in rate hearings by the state PUC.
Having all sorts of electric utility segments provided as merchant stuff complicated the rate structure even before rooftop solar became more than rounding error.

 

[bacon4life]

Vertically integrated utilities did not need revenue quality metering at generation plants. Using relay class CT's with 5% error worked fine for SCADA controls. Retrofitting revenue quality metering is one of the new costs imposed by deregulation re-regulation. Ideally, deregulation re-regulation allows the most efficient plants to be dispatched first, thereby saving lots of money. Hopefully, the more efficient dispatch of generators more than makes up for the huge increase in metering/billing complexity.

Note that there are often several different kinds of metering values that come from interchange meters:
1) Realtime MW values for use in SCADA/Automatic Generation Control. The values are usually transmitted to both parties every 2 to 15 seconds. These are power rather than energy measurements.
2) Hourly MWh values for use in SCADA/AGC to make sure planned transactions match what actually occurred during the hour.
3) 5 minute or 60 minute interval MWh values for billing purposes. The are often download once per day from the meter by an independent meter reading system such as MV90. It can take several months for the actual billing settlements to be resolved.