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Philosophical questions that highlight how absurd a fee on self-generation is.

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Can you link to a technical publication or something? How reduced demand due to generation and reduced demand due to reduced demand could effect the grid differently makes zero sense to me... I'm not referring to exports... only smaller imports.

There is the concept of native load. If you remove all of the distributed generation, there is a certain amount of load that needs to be served. If you reduce your demand through energy efficiency upgrades, your native load decreases. How would the utility know this? If they give rebates for energy efficient appliances or upgrades, they are keeping track. If you reduce your load due to onsite solar generation, your native load stays the same. If a very cloudy day comes, your solar may only put out 10% of peak, and the utility must be ready to meet that load. Also, if there are temporary faults on the network, IEEE 1547 compliant inverters will turn off, so the utility must meet 100% of the native load during the 10-15 minute period before they turn back on again. Then there is the variability. On partly cloudy days, a 5 kW solar system may fluctuate it's output between 1 and 5 kW very rapidly. A normal house would not do that. If lots of houses with solar start doing that, there can be voltage flicker problems.
 
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There is the concept of native load.

How are native load fluctuations intrinsically different? Cloudy days = less generation but cold/hot days = more demand. It sure seems like they're singling out one type of variability. There are other types of 'native load' that are far more stressful. Tankless hot water heaters come to mind. In a split second the grid is forced to deliver >10kW of power. Not even a solar eclipse would cause that kind of instantaneous surge from a PV system. If anyone should pay an extra ~$50/mo to support grid upgrades it's the ratepayers that use those...

And... numerous studies have concluded that the moment to moment fluctuation of a single PV system due to clouds are negligible to the grid since they get smoothed out over a service area.

Should every ratepayer pay the same to support the grid or should that rate be based on how much stress they place on the grid? Should there be incentives for storage and demand response?
 
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How are native load fluctuations intrinsically different? Cloudy days = less generation but cold/hot days = more demand. It sure seems like they're singling out one type of variability. There are other types of 'native load' that are far more stressful. Tankless hot water heaters come to mind. In a split second the grid is forced to deliver >10kW of power. Not even a solar eclipse would cause that kind of instantaneous surge from a PV system. If anyone should pay an extra ~$50/mo to support grid upgrades it's the ratepayers that use those...

Most native load fluctuations are not as severe as what a solar PV can do. Even those that are, like the tankless heaters, won't all be shutoff for 5 -15 minutes following a temporary grid fault due to anti-islanding protection.


True, over an entire service area, but not on a single distribution feeder, which is where the voltage problems will occur. Looking at Figure 5 in the linked document shows how bad one system can be. True the line for 100 PV doesn't fluctuate much, but those are geographically dispersed over all of Germany. If the 100 were clustered into the same couple of blocks, it would look much more like the single solar line.
 
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YG(rid)MV, but it looks like flicker from local changes in PV output isn't an issue at 7.3kW/HC (House Connection) when compared to flicker from load.

In conclusion it can be stated that no higher flicker levelsare caused by PV systems. The determining factor remainsstill the load. This statement is only applicableunder the current planning conditions. If these conditionschange, for example the maximum voltage hub in lowvoltage grids of 3 % [VDE-4105], these statements losetheir validity. If the PV penetration reaches higher valuesin the future this study has to be implemented again toinvestigate the influence of these new high penetrationson the flicker level. Nevertheless, there are no high deviationsin the flicker level expected.

https://mediatum.ub.tum.de/doc/1191470/1191470.pdf

There are a lot of things at play. Every utility has a different philosophy with what they want to do about solar. Some of them don't want to deal with it, and make the solar owners cover all of the projected costs of grid upgrades as well as operate in ways that cause minimal disturbances. A lot of time this is a reflection of the majority opinion of their rate payers. Other utilities embrace solar, spread the costs to all rate payers, and then try can come up with innovative solutions to make it cheaper. The thing to remember is that in all cases, the costs can be justified from an engineering standpoint, even if they aren't the best long term solution.
I think a utility expecting an owner cover all the costs of grid upgrades and operate in a way that causes minimal disturbances is reasonable. I also think an owner (or group of owners) should be able to choose what they do to successfully integrate based on some realistic and reasonable spec the utility sets, so they can optimize costs on their side. If it's less expensive for them to regulate production/consumption (battery pack and/or DR and/or load dumping) on their end than it is to pay for grid upgrades, they should be able to do that, and also be paid a fair rate (whatever the prevailing rate is less distribution costs) for useful excess generation. I think every owner should be able to do that, even if they don't have PV panels, but I think PV owners are a great example because they can regulate production in addition to consumption.
 
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So..... I found the advice notice from SPS... they're going to request a rate increase for Solar production from $0.036/kWh to $0.043/kWh...

Everyone is making such a big deal about NV Energy. NM is way, way.... WAAAAY worse :cursing:

Tell the NM PRC not to be active participants in destroying your kids future quality of life.


Patrick Lyons is the ring leader of the Solar PV death squad.

165x200-lyons.jpg

Patrick H. Lyons
Commissioner - District 2
[email protected]

1120 Paseo De Peralta
P.O. Box 1269
Santa Fe, New Mexico 87504
(505) 827-4531


If you care about clean energy.... and you can be in Santa Fe on April 28.... please be in Santa Fe on April 28.
 
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These debates get political instead of logical which is unfortunate.

Here in NC, solar users are on a peak demand system. I pay less per kwh but pay a hefty demand fee. It is between $4 and $5.50 a peak kw for 15 minutes. It is logical. So in April, my demand charge might exceed my usage charge. I have no chance of a zero month - which makes sense I use the grid every month.

What the rate structure encourages is EV's, off peak usage, not oversizing PV - all good things.

Sure I could go off grid. I'm close to wk057 - geographically. I'll guess that his system is $50k - ignoring DIY etc. I have about $1200 a year in total fees (was $2000 before my 6 kw system). So 40 year payback - and no one expects his batteries or panels to last that long at full efficiency/capacity. And guess what - he had to use the grid in December (by memory). So he really needs more batteries and panels. But doesn't matter - payback is never.

EVs destroy the idea of going off grid. In December, you would need so many panels to do your house and drive your cars, that it isn't practical. I generated 250 kwh in December and used 2000. I have heat pumps (but NG backup) and solar hot water (electric backup) and 2 EVs. So the hot water needs a lot of backup and we all know car efficiency goes down in the winter.

So all the anti-utility people can go off grid but it is really costly. And with EVs in December, it is really costly.
 

Just a quick comparison vs. my bill.

I'm part of a co-op that has made a gradual change over the past decade. I've talked about it before in several threads, but this falls squarely within the topic being discussed here. The co-op has made several moves over the years to move the meter charge higher to reflect the true fixed costs of attaching to the grid, and reducing or halting increases to the usage cost.

This person pays $7.90 for service availability (my "meter charge"). I currently pay $45/month for that (up from $16 about 6 years ago).

The effect of this change over the past decade was that the consumers with less consumption felt some more pain now. For years, though, the larger consumers have been subsidizing the smaller consumers because fixed costs were integrated into the variable cost pricing. The way that I look at it is that they got one hell of a deal for a long time and new they're getting to the actual real costs (although not a true-up). In some cases, some of the corner cases had to go find new ways to get power and installed their own solar+storage (the lean-to shed in the middle of the farmer's field that has a couple of lights, or the barn with separate service meters from the home). Commercial (non-residential/non-farm) customers pay demand charges for their grid connection size.

This change was easier for us to make. As co-op members, we own the utility and so we have the ability to shape the policy without a lot of government interference. Investor-owned utilities have a tougher time and have to battle a tougher viewpoint from the PUC's concerned that poor little Martha will have her bill go up (despite the fact that she's been getting a bargain-basement price the whole time).

I believe that because of the co-op's approach, distributed solar generation is much easier for my co-op to deal with. They give up to 3 months' credit at retail price for excess generation; they're even talking about changing the policy to make those credits refundable via cash back to the members that generate the power. Their policy is fairly liberal, allowing for systems of up to 40 kW before you are required to become a generator. (EDIT: Note that excess generation gets put into a kWh "bank" and cannot offset meter charges. If you have a meter and therefore a connection to the grid, you pay $45/month minimum even with zero usage.)

I get why these policies are being put in place -- with distributed generation, rate structures that implement fixed cost recovery in the variable usage price will suffer with a huge penetration of solar.

That generally leads to the question of "can I go off-grid"?

As to the argument about sizing systems, I'm finding this to be true in my modeling as well. There are two cases over the past year alone where I have had a prolonged stretch of 5 days with below-average generation from my system. I would require a (roughly) 36-40 kW system to offset all of my power usage for my service here - I currently have half that. From Feb 28 to Mar 4 last year, during the entire 5 day period I generated only 65 kWh with an 18 kW system - let's double that for a system twice the size - 130 kWh.

My demand during that time period averages about 68 kWh a day (~2100 kWh in the early spring months, prior to A/C units). As a result, over those 5 days I would have run a deficit of 210 kWh (EDIT: wrong value - 210 kWh assuming a system twice the size that would be net-zero). There's just no way to size any system for that and be off-grid without having to make pretty major sacrifices. Luckily we drive two Teslas, so we could hold off on charging them - that would save us probably 40-50 kWh over that time frame. However, that still leaves a deficit of over 150 kWh.

The system I would need to install to go completely off-grid while saving for those two events in the past year would be quite substantial. To get my deficit down to something reasonable that could be approachable with storage - say 50 kWh - would require a system about 4x the size of what I have today plus storage costs.
 
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Sure I could go off grid. I'm close to wk057 - geographically. I'll guess that his system is $50k -

He's not 'off-grid'... he has a 'grid-assisted' system. He still uses the grid when his batteries are depleted. He never revealed how much his system cost but I'm pretty sure it was north of $100k... his inverters alone were ~$50k, the panels were ~$35k and the charge controllers ~$10k. That's ~$95k and we haven't even counted the batteries, racking and wire. He did say that costs kinda got out of control... which is why I'm not a huge fan of hybrid systems... they're expensive. By comparison I could build a 50kW grid-tie system for <$60k.

But... things are improving; more efficient and less expensive battery backed systems are only a few years away. It's important to differentiate between 'off-grid' and 'grid-assisted'. SPS Xcel has succeeded in making 'grid-assisted' systems more cost effective than 'grid-tied'. The owner of a 8kW system would save >$700/yr now in NM with a 'grid assisted' system making the extra $4k you would need to spend well worth it. But in many ways it's a pointless expense; the only real benefit is you're circumventing Xcels punitive fees. The grid loses clean energy due to curtailment when the batteries are charged. You would needlessly cycle batteries when there's is probably clean wind available on the grid.

The key point that wk misses is that the objective isn't to personally use 100% clean energy... a romantic notion but there's an asymptotic approach to 100% that gets more and more difficult... it's displacement. With a grid assisted system you can't displace more that you consume since you're never exporting. I might burn 5lbs of Nat Gas at night since I'm grid-tied and don't have batteries but the extra energy I exported during the day displaced 15lbs. What's the better outcome... personally using 100% clean energy OR having net negative fossil fuel consumption?

My home in NM has produced 50MWh in 3 years. I've consumed 30MWh. If I had a 'grid-assisted' system I would have used solar for EVERYTHING but... fossil fuels would have had to make up for that 20MWh that wouldn't have been exported. IMO that's a terrible trade. Wk was right when he said the grid isn't a battery... it's not... it's a marketplace. Why would you go through the effort and expense of packaging your product if there's a line of customers that want it now? If there's demand on the grid it's more efficient to export power for consumption than to store it in a battery. We're not far from the day that statement won't be true but until then grid-tied systems make more sense... and when storage is required it's the higher voltage systems like the Tesla Powerwall that would be the tool of choice... not 48v systems.

Here in NC, solar users are on a peak demand system. I pay less per kwh but pay a hefty demand fee. It is between $4 and $5.50 a peak kw for 15 minutes. It is logical. So in April, my demand charge might exceed my usage charge. I have no chance of a zero month - which makes sense I use the grid every month.

I'm actually becoming a big proponent of demand fees... that's the most accurate metric to ensure that everyone is paying to support the infrastructure. It encourages storage since a modest battery can buffer out those spikes and have a huge impact on your bill. I just hope we can find some way to balance it a bit better... if I really needed to charge my car quickly for some reason it would suck to get hit with a $50 additional fee since I charged at 20kW that one time last week.
 
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