diy solar

diy solar

The end of net metering

If I understand "Net metering" in 1:1 ... if in a quarter billing period you use 2000kWh and generate 1000kWh, then you get billed for 1000kWh.

It sounds pretty straight up and fair. In fact it would be, but only if it was based on instantaneous power and not consumption.

As it's based across "billing periods" which I imagine are monthly or quarterly, then it is not in anyway fair or balanced. The grid operators will have to seek a return or change that system as it's not sustainable in anyway.

In many places the tariff is based on "feed in" rates. You have two meters. One measures what comes in and one measures what goes out.

This is fair because it counts "total real power" in BOTH directions. Consider this scenario.

5:00am - You get up and consume 1kWh before dawn and drive to work.
6:00pm - You get home from work and see the solar power system has exported 10kWh.
10:00pm - You consume another 9kWh before going to sleep.

Your "NET" bill for the day is 0kWh. However, a total of 20kWh has been "serviced" by the grid. YOU have used the grid as a storage system basically. On "Net" billing, the grid is just a battery.

It should not be free. It should definitely not be free to generators based on net consumption.

As a minimum make the net billing peroid the industry standard 15 mins based on peak flow in or out. Then charge distribution, transmission costs as separate line items, including "apparent power" and a variable price.

In that model, when everyone in the street is pumping out solar while they are at work, the price of those kWh could very well go negative, giving incentive for people to use "grid controllable" inverters.

EDIT: Note. That later thing, billing by 15min and prices going negative, is pretty much the reality a lot of grid providers face these days.
 
Originally, net billing occurred at the end of each 1-year period. The grid served as a free battery.
Time of use metering was optional, so with higher rates Noon to 6:00 PM (when demand was highest) I might get credit of $0.32/kWh, and for night time loads I was charged $0.08/kWh. My panels were oriented for 2:00 PM sun, and I estimated I got 1.5 kWh back for every 1.0 kWh exported. That was 20 years ago.

Today, there is considerably more PV product during middle of the day, making a large dent in California's consumption.
The grid's service of carrying power I produce to others during the day has value; they could be compensated.
I think that due to PV production, the utility has gotten away with not having to upgrade infrastructure as much to support growth of consumption. That is value we bring them, so I don't think our credit for export should just be wholesale generation, should include their savings in long distance transmission.

Utility wants to say the power we produce is only worth the market price of the last kWh, which may be negative (on occasion they have paid other states to take a little bit). But if we were to turn off PV production, utility would have to buy a massive amount of power from peaker plants, and would have to transmit it. That price per kWh should be used. Avoided cost.

Utility tried to get PUC to approve charging us net money (about $0.03/kwh) for all power we produce and deliver to them. And $0.08/kWh for all power we produce and use immediately. The PUC instead approved $0.00/kWh for export and $0.05 for power we make and use. But that wasn't implemented; a different credit of a couple cents per kWh export is now in effect for new PV adopters. So they are trying other approaches to go in effect in 2025: Flat monthly charge for infrastructure, smaller charge per kWh.
 
The idea that local solar gets used locally is only true when there is demand for it.

The largest consumers by and far are industry and industry place their plants as close to the power plants as possible. For many reasons, not least the lower cost of transmission and distribution, but also in the engineering and power loss.

The grids are designed that way, where the highest power links are the shortest distance or possibly on dedicated circuits.

When the middle class's solar hits peak output, most of them are out at work in offices in cities and in those industies. So the power their home is producing has to make it way "backwards" through teh grid. The grid was designed to have surplus at the top, more than the bottom end of the trees.

There are however some major concerns when power flows bi-directional based on solar generation versus demand. The intermittency of solar means an entire area can go from high generation to net load in a matter of seconds. The "peaker" turbines and plants, hydro, grid stabilisationstorage, have to be ready and work hard to not drop voltage or frequency while power effectively slows and reverses net flow. At one moment the "leaf nodes" are pushing power up the tree causing back feed on the generators which have to be bypassed or even braked to prevent overrunning the frequency, to suddenly that becoming a net load in seconds.

It's similar to the british "World cup final", "cup of tea" problem. Basically the grid load could jump 10 fold if there was extended time, because every household in the country turned in would all in unison get up and switch on a 3kW kettle for a cup of tea. Even the ad breaks on national events caused load spikes from people flushing toilets and all the pressure maintaining pumps firing up in the water mains.

Knowing when and how much solar is about to go into or come out of shade....

Well... that's why they want access to your EV battery. It's also why I gaurantee that "off grid electrical storage" will become "taboo".

Balancing the grids of the future is proving to be extremely difficult. In some places they are even abondoning AC in favour of DC. Simply to get around the problem that renewables don't have those millions of tons of steel all rotating at exactly the same frequency to keep them stable. Rather than face phasing issues, they are setting up high voltage DC interlinks.
 
Hedges said:
Utility wants to say the power we produce is only worth the market price of the last kWh, which may be negative (on occasion they have paid other states to take a little bit). But if we were to turn off PV production, utility would have to buy a massive amount of power from peaker plants, and would have to transmit it. That price per kWh should be used. Avoided cost.
Click to expand...
Only if you controlled all the pv production. You are only worth the value of the last turbine to spin up (or cost to spin down - it costs to spin down base load generation to spin it back up later in the day. Or to wheel it to farther areas that can use the power).

Note: in theory, you should be charged the distribution cost of the Energy exported. Think of it as the cost the utility incurs to take the power from you. If you want to setup the transmission lines to sell the power directly to a nearby factory, go ahead. That is why your power is only worth the generation cost, and not the full amount you are charged for each kWh you consume.

Either store the excess yourself, or the utility has to incur the cost of storing all the electricity above its base load generation for use later in the day. Someone has to pay for the time shifting.
 
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Hedges said:
Originally, net billing occurred at the end of each 1-year period. The grid served as a free battery.
Time of use metering was optional, so with higher rates Noon to 6:00 PM (when demand was highest) I might get credit of $0.32/kWh, and for night time loads I was charged $0.08/kWh. My panels were oriented for 2:00 PM sun, and I estimated I got 1.5 kWh back for every 1.0 kWh exported. That was 20 years ago.

Today, there is considerably more PV product during middle of the day, making a large dent in California's consumption.
The grid's service of carrying power I produce to others during the day has value; they could be compensated.
I think that due to PV production, the utility has gotten away with not having to upgrade infrastructure as much to support growth of consumption. That is value we bring them, so I don't think our credit for export should just be wholesale generation, should include their savings in long distance transmission.

Utility wants to say the power we produce is only worth the market price of the last kWh, which may be negative (on occasion they have paid other states to take a little bit). But if we were to turn off PV production, utility would have to buy a massive amount of power from peaker plants, and would have to transmit it. That price per kWh should be used. Avoided cost.

Utility tried to get PUC to approve charging us net money (about $0.03/kwh) for all power we produce and deliver to them. And $0.08/kWh for all power we produce and use immediately. The PUC instead approved $0.00/kWh for export and $0.05 for power we make and use. But that wasn't implemented; a different credit of a couple cents per kWh export is now in effect for new PV adopters.
Click to expand...

Hedges said:
So they are trying other approaches to go in effect in 2025: Flat monthly charge for infrastructure, smaller charge per kWh.
Click to expand...
Has anything been decided about new rules / fees going into effect in 2025?

Will these new rules / charges going into effect in 2025 impact existing NEM customers or only new installs?

It’s pretty clear the TOU billing rates are going to continue to depress peak-solar-production period electricity rates and export credits and to continue to hack up peak period electricity rates in afternoon/evening and next near-peak rates in the morning, but I was not aware of other changes coming in 2025.

I’m interested in any links you have to new changes expected to come into effect by 2025…
 
The problem I have with waiting until your current agreement is about up is legislation and regulations change over time. Sometimes the early bird not only gets the worm but is grandfathered in.

Utilities are pushing for more regulation on solar that is not grid tie. They see a dwindling customer base if widespread adoption takes place. Of course, politicians will say they are for the "poor people" and only the rich can afford solar, so the cost of production and distribution needs to be spread across a greater number of customers being fleeced.

Another aspect is inflation and how that will affect the cost to produce your own power. Paying now and locking in the price of production can be quite beneficial to the return of the system. An example is $40K with inflation at 5% compounded yearly. The system would cost an additional $8.6K in just 4 years time. That is $2,150 per year. For the 12Kwh/per year you currently use, that would be $0.179/Kwh for inflation on the cost of a system.

Is it possible the price for a system might come down with increased competition and widespread adoption? It is possible but considering the far reaching effects of inflation on the costs of production, it would take a big increase in efficiency for production to keep those costs down.
 
fafrd said:
Has anything been decided about new rules / fees going into effect in 2025?

Will these new rules / charges going into effect in 2025 impact existing NEM customers or only new installs?


I’m interested in any links you have to new changes expected to come into effect by 2025…
Click to expand...

Just seeing articles. $20/month for poor people, up to $93/month for high income people in PG&E district, $145/month for high income in Southern California.
To be revenue neutral, reduced per kWh rate but no word on what that is.

Rate changes have generally applied to everybody regardless of what net metering. Multiple rate plans, sometimes obsoleted and we're bumped onto another.

California law requires new homes to have PV (buyer pays for that), credits for export are below retail, so home buyers are required to give PG&E power for a loss. This new plan increases their monthly fee and further reduces retail rates, but may not affect NEM 3.0 credits which I think are related to wholesale power cost.
 
DIYrich said:
Only if you controlled all the pv production. You are only worth the value of the last turbine to spin up (or cost to spin down - it costs to spin down base load generation to spin it back up later in the day. Or to wheel it to farther areas that can use the power).

Note: in theory, you should be charged the distribution cost of the Energy exported. Think of it as the cost the utility incurs to take the power from you. If you want to setup the transmission lines to sell the power directly to a nearby factory, go ahead. That is why your power is only worth the generation cost, and not the full amount you are charged for each kWh you consume.

Either store the excess yourself, or the utility has to incur the cost of storing all the electricity above its base load generation for use later in the day. Someone has to pay for the time shifting.
Click to expand...
For an example of this, in my last months electrical bill from AES I was charged 12.38 for my supply total and then they added 14.66 for delivery.
So my goal now is to use 0 kw to see if I will still have a delivery or distribution charge.
 
You could compare to an earlier bill, see which charges are in proportion to consumption and which are fixed.

If you pay ~ $15/month fixed charge for connection, $180/year, that is worthwhile for a highly reliable, economical, silent, unlimited generator.
If you have net metering, don't have to buy a battery for storage, it is a fantastic deal.
 
timselectric said:
Grid-tied is for suckers. Or grid connected in any way, for that matter. Get out while you can.
Otherwise, you will be left carrying the grid alone.

Disclaimer: this is just my opinion.
Click to expand...
Has anybody considered the wear and tear on their EV from the power company using the power and then you recharging adding to the battery cycle count basically, you’re paying for the storage system maintenance on the system and all the wear and tear shortening the life of your EV

To me that’s like going to a restaurant where you have to supply the food and drink cook the food and serve the food and they still give you a hefty bill. It doesn’t make sense.
 
Hedges said:
Just seeing articles. $20/month for poor people, up to $93/month for high income people in PG&E district, $145/month for high income in Southern California.
To be revenue neutral, reduced per kWh rate but no word on what that is.

Rate changes have generally applied to everybody regardless of what net metering. Multiple rate plans, sometimes obsoleted and we're bumped onto another.

California law requires new homes to have PV (buyer pays for that), credits for export are below retail, so home buyers are required to give PG&E power for a loss. This new plan increases their monthly fee and further reduces retail rates, but may not affect NEM 3.0 credits which I think are related to wholesale power cost.
Click to expand...
I hadn’t realized the ruling is expected by next year and could impact minimum monthly charges as early as 2025: https://sfstandard.com/business/pge-rates-could-drastically-change-based-on-your-income/

‘PG&E customers earning less than $28,000 annually would pay $15 per month for electricity; customers earning between $28,000 and $69,000 would pay $30; and those earning $69,000 to $180,000 would pay $51 a month. Households earning more than $180,000 would pay $92 a month.’
 
"The flat rate pricing model"

Most of these articles make no mention of a per kWh rate which will also be charged.
Probably so majority of the public will think, "Just $15 or $30 flat rate per month; that's less than I pay now!" and will support it.
 
Hedges said:
"The flat rate pricing model"

Most of these articles make no mention of a per kWh rate which will also be charged.
Probably so majority of the public will think, "Just $15 or $30 flat rate per month; that's less than I pay now!" and will support it.
Click to expand...
We’ll see how it all plays out. I’ll be surprised if we see major changes approved by next year - they are going to need at least 18 months to digest the changes they have just approved for NEM 3.0.

I’m expecting differential TOU rates to be further tweaked / amplified and that may well start 2 years from now, but those changes generally get broadcast at least 12 if not 18 months before imposition…
 
Zwy said:
The problem I have with waiting until your current agreement is about up is legislation and regulations change over time. Sometimes the early bird not only gets the worm but is grandfathered in.

Utilities are pushing for more regulation on solar that is not grid tie. They see a dwindling customer base if widespread adoption takes place. Of course, politicians will say they are for the "poor people" and only the rich can afford solar, so the cost of production and distribution needs to be spread across a greater number of customers being fleeced.

Another aspect is inflation and how that will affect the cost to produce your own power. Paying now and locking in the price of production can be quite beneficial to the return of the system. An example is $40K with inflation at 5% compounded yearly. The system would cost an additional $8.6K in just 4 years time. That is $2,150 per year. For the 12Kwh/per year you currently use, that would be $0.179/Kwh for inflation on the cost of a system.

Is it possible the price for a system might come down with increased competition and widespread adoption? It is possible but considering the far reaching effects of inflation on the costs of production, it would take a big increase in efficiency for production to keep those costs down.
Click to expand...
Youre also paying now with more expensive dollars so the inflation thing is kind of a wash
 
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DIYrich said:
Not a loss if the marginal cost of production is $0.00. Cost of hardware is amortized against kWh consumed.
Click to expand...

Rooftop GT PV costs $3/W installed, amortizes out to $0.10/kWh over 20 years.
If utility credits $0.03 or $0.05/kWh for export, it is a net loss.

Requiring new homebuyers to pay for PV might have seemed like a good idea at the time, but since net metering was done away with, it constitutes theft from the individual and a gift to the utility.

I think the government has no right to order that - confiscation of private property without compensation for the public good. The courts likely won't agree; they haven't when it comes to landlord-tenant issues.
 
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