YOU: Fix the US Energy Crisis

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In summary: Phase 3, 50 years, decision-making, maintenance, and possible expansion. -Continue implimenting the solutions from Phase 2, with the goal of reaching net-zero emissions. This would be a huge undertaking and would cost hundreds of billions of dollars. -Maintain the current infrastructure (roads, buildings, factories) and find ways to make them more energy efficient. -Explore the possibility of expanding the frontier of science and technology, looking into things like artificial intelligence, nanotechnology, and genetic engineering. This could lead to new and even more amazing discoveries, but it would also cost a fortune.
  • #1,261
mheslep said:
As you indicated in the first sentence about efficiency, only the cost matters. If it is cheaper to discard than store, discard (curtailment) is better. At the moment, with subsidies for wind, utilities choose surplus wind that wind operators with a 23 cent/MWh subsidy pay them to use (negative cost). The utilities idle or blow steam from conventional power sources instead. If wind capacity were to increase so that a moments of full capacity output equaled the entire load, then wind is discarded. This is already http://nawindpower.com/online/issues/NAW1412/FEAT_04_Renewable-Energy-Faces-Daytime-Curtailment-In-California.html
As we get more and more distributed sources (Solar homes) the waves in the grid will get bigger.
We will need a better mechanism to control the surplus.
 
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  • #1,262
johnbbahm said:
I am not talking about net metering (which is a dead horse) or subsidies, just reducing the amount of power purchased.
If the amount of power purchased, decreases by $60 a month, based on a full price $10K system,
it is real savings.
How do you get there without selling power to the utility or using a mandated price? The actual value of a grid connected solar system, to a utility unburdened by mandates or net metering, is only for the fuel saved by the utility, or about 3 cents per kWh. Large scale commercial and industrial billing already works this way. The average US residence uses ~1000 kWh per month. If a solar array shaves a quarter of that, 250 kWh, the savings is $7.5/month.
 
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  • #1,263
johnbbahm said:
For the solar, it really is just comparing what you pay, to what you reduce by.
If you do not sell any back to the grid, you only get the savings,
but those are a real one for one of the price per Kwh you pay.
You save money that others have to pay for you. And you have to pay for it if others save that money. It's like a "you don't have to pay taxes for road maintenance any more" card, replace road maintenance by electricity grid and taxes. If you own one, you save money - but others have to pay for it. If others own the card, you have to pay more.

Rooftop solar will never be as constant and steerable as conventional power plants. Matching demand and production is getting more and more challenging.
 
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  • #1,264
mfb said:
You save money that others have to pay for you. And you have to pay for it if others save that money. It's like a "you don't have to pay taxes for road maintenance any more" card, replace road maintenance by electricity grid and taxes. If you own one, you save money - but others have to pay for it. If others own the card, you have to pay more.

Rooftop solar will never be as constant and steerable as conventional power plants. Matching demand and production is getting more and more challenging.
If you are only using the grid to assist your solar system, you are still paying for the grid.
There will still be a grid attachment fee.
Even if you are selling power back to the grid (at wholesale prices), there will be a some sort of use fee.
these are the things that need to be worked out before solar can go mainstream.
And yes, Matching demand and production will get more challenging, which is why we will need a dump,
to place the excess energy.
 
  • #1,265
The mismatch between solar and peak load (actual and forecast in coming years):

20297.jpg
in California

http://nawindpower.com/online/issues/NAW1412/FEAT_04_Renewable-Energy-Faces-Daytime-Curtailment-In-California.html
 
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  • #1,266
mheslep said:
How do you get there without selling power to the utility or using a mandated price? The actual value of a grid connected solar system, to a utility unburdened by mandates or net metering, is only for the fuel saved by the utility, or about 3 cents per kWh. Large scale commercial and industrial billing already works this way. The average US residence uses ~1000 kWh per month. If a solar array shaves a quarter of that, 250 kWh, the savings is $7.5/month.
Ok, let's say the normal homeowner uses an average 1000 Kwh per month.
Their electric bill with taxes and fees averages say $120 per month.
Installing a solar system that produces an average of 600 Kwh per month, will reduce the
monthly expenses by roughly $60 a month, their remaining electric bill will be $60 a month.
The homeowner who paid for the system , saves the money.
 
  • #1,267
johnbbahm said:
Installing a solar system that produces an average of 600 Kwh per month, will reduce the
monthly expenses by roughly $60 a month,
Not sure i buy that.
It'll have to make ~20 kwh/day to save that much 10 cents/kwh electricity
meaning ~ 3kw during the six or so sunny hours surrounding noon.

His house load that time of day is probably one kw or less meaning he sells his leftover two kw back to the utility not at retail but at whatever is the mandated buyback price. If that price is more than the utility's cost to deliver then his neighbors are subsidizing his overpriced kwh's.
That i think was mhselep's point ?

If on the other hand he absorbs his whole 3kw in say a hot water heater, displacing utility's 10 cent kwh's , he has indeed saved himself $60 without impacting his neighbors.
 
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  • #1,268
johnbbahm said:
Ok, let's say the normal homeowner uses an average 1000 Kwh per month.
Their electric bill with taxes and fees averages say $120 per month.
Installing a solar system that produces an average of 600 Kwh per month, will reduce the
monthly expenses by roughly $60 a month, their remaining electric bill will be $60 a month.
The homeowner who paid for the system , saves the money.
That can't be done without selling more power than is used by the residence back to the utility, not without storage or shifting demand. That is, 1000 kWh per month means an average 1.3 kW house load over 30 days-24hr. Production of 600 kWh from the roof array during the five (peak equivalent) hours of solar means producing 4 kW from the solar array, or sending 2 or 3 kW back to the utility. That's net metering.
 
  • #1,269
jim hardy said:
Not sure i buy that.
It'll have to make ~20 kwh/day to save that much 10 cents/kwh electricity
meaning ~ 3kw during the six or so sunny hours surrounding noon.

His house load that time of day is probably one kw or less meaning he sells his leftover two kw back to the utility not at retail but at whatever is the mandated buyback price. If that price is more than the utility's cost to deliver then his neighbors are subsidizing his overpriced kwh's.
That i think was mhselep's point ?

If on the other hand he absorbs his whole 3kw in say a hot water heater, displacing utility's 10 cent kwh's , he has indeed saved himself $60 without impacting his neighbors.
In my area, my peak usage parallels when solar would be peaking.
looking at my usage graph from last week, my hourly Kwh usage peaked about noon at 6 kwh,.
There is no surplus purchase for me, the system would only be grid assist, I just save what I save.
 
  • #1,270
mheslep said:
That can't be done without selling more power than is used by the residence back to the utility, not without storage or shifting demand. That is, 1000 kWh per month means an average 1.3 kW house load over 30 days-24hr. Production of 600 kWh from the roof array during the five (peak equivalent) hours of solar means producing 4 kW from the solar array, or sending 2 or 3 kW back to the utility. That's net metering.
As I said above in my area usage closely parallels solar production.
Net metering is not an option, any surplus just goes back to the grid for free.
For solar to actually expand, net metering has to end, many early adopters will not like that,
but as you point out the grid must be paid for.
 
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  • #1,271
johnbbahm said:
In my area, my peak usage parallels when solar would be peaking.
looking at my usage graph from last week, my hourly Kwh usage peaked about noon at 6 kwh,.
There is no surplus purchase for me, the system would only be grid assist, I just save what I save.
If you're using all you can make as you make it , it's a better deal for all.
When the utility is mandated to buy renewable at more than cost of fossil that cost is spread across all customers. Some utility bills itemize it to make customers aware.
At one time some utilities let people sign up to buy their power at a higher "Renewable" rate. Surprisingly a lot of people did. i guess they felt they were doing the planet a favor. Really they were doing the utility and its other customers a favor. It is a praiseworthy sentiment, though.
 
  • #1,272
jim hardy said:
If you're using all you can make as you make it , it's a better deal for all.
When the utility is mandated to buy renewable at more than cost of fossil that cost is spread across all customers. Some utility bills itemize it to make customers aware.
At one time some utilities let people sign up to buy their power at a higher "Renewable" rate. Surprisingly a lot of people did. i guess they felt they were doing the planet a favor. Really they were doing the utility and its other customers a favor. It is a praiseworthy sentiment, though.
I have been working the numbers over for years, it is starting to look practical.
Some form of storage would help even out the daytime with nighttime usage, but that is also expensive.
 
  • #1,273
johnbbahm said:
As I said above in my area usage closely parallels solar production.
Net metering is not an option, any surplus just goes back to the grid for free.
For solar to actually expand, net metering has to end, many early adopters will not like that,
but as you point out the grid must be paid for.
Ok good, so for the moment we consider only the cases where the solar owner uses all that he can produce, with a fortunate and unusual 24hr load that peaks with coincident solar output.

Still, if we stick with our reference case of a $120 a month pre solar electric bill, the utility needs, say, 80% of that to support the grid, $96 a month, even if the owner never draws a kWh. If the utility actually priced residential customers this way (as it does with industrial connections), then with a PV array the owner cuts kWhs in half (at best) and the owner saves $12 a month at best. The solar array never pays off with a discount rate applied.

From the utility viewpoint, even with connection pricing that pays for the grid, they can argue that the advent of distributed solar generation forces them to ramp up and down their sources much more rapidly (e.g. per the coming California example illustrated in the graphic posted up thread). That is, they approach the case of going from nothing to full power at 5 or 6pm everyday. This kind of operation lowers their efficiency they argue, driving up costs, so the value of distributed solar to the system rapidly lowers as solar penetration goes beyond a dozen percent or so.

All of these consequences become apparent immediately, I think, upon consideration of taking an average residence off the grid completely, doing the utility's job with solar and battery storage alone. Sure, a few beach shacks in the tropics can manage off the grid, but as far as I know there is not a *single* example of an average size home going off grid in the US, not without a generator or grid connection hiding behind the curtain.
 
  • #1,274
johnbbahm said:
I have been working the numbers over for years, it is starting to look practical.
Me too. But the stinkin' numbers keep changing on me!
Some form of storage would help even out the daytime with nighttime usage, but that is also expensive.

I was thinking about my "red-neck swimming pool under the house" idea this morning, and decided to google it.

It seems that there are red-necks in Canada.

Drake Landing Solar Community [wiki]
The Drake Landing Solar Community (DLSC) is a planned community in Okotoks, Alberta, Canada, equipped with a central solar heating system and other energy efficient technology. This heating system is the first of its kind in North America, although much larger systems have been built in northern Europe. The 52 homes in the community are heated with a solar district heating system that is charged with heat originating from solar collectors on the garage roofs and is enabled for year-round heating by underground seasonal thermal energy storage (STES).
The system was designed to model a way of addressing global warming and the burning of fossil fuels. The solar energy is captured by 800 solar thermal collectors located on the roofs of all 52 houses. It is billed as the first solar powered subdivision in North America, although its electricity and transportation needs are provided by conventional sources.
In 2012 the installation achieved a world record solar fraction of 97%; that is, providing that amount of the community's heating requirements with solar energy over a one-year time span.

Of course, this idea might not make sense to someone who doesn't live in or near Canada. But the principle is reversible:

Seasonal thermal energy storage [wiki]
...
the natural cold of winter air can be stored for summertime air conditioning.
...

mheslep said:
...Sure, a few beach shacks in the tropics can manage off the grid...

I see I'm not the only one who questioned how he did that. :biggrin:
 
  • #1,275
mheslep said:
Ok good, so for the moment we consider only the cases where the solar owner uses all that he can produce, with a fortunate and unusual 24hr load that peaks with coincident solar output.

Still, if we stick with our reference case of a $120 a month pre solar electric bill, the utility needs, say, 80% of that to support the grid, $96 a month, even if the owner never draws a kWh. If the utility actually priced residential customers this way (as it does with industrial connections), then with a PV array the owner cuts kWhs in half (at best) and the owner saves $12 a month at best. The solar array never pays off with a discount rate applied.

From the utility viewpoint, even with connection pricing that pays for the grid, they can argue that the advent of distributed solar generation forces them to ramp up and down their sources much more rapidly (e.g. per the coming California example illustrated in the graphic posted up thread). That is, they approach the case of going from nothing to full power at 5 or 6pm everyday. This kind of operation lowers their efficiency they argue, driving up costs, so the value of distributed solar to the system rapidly lowers as solar penetration goes beyond a dozen percent or so.

All of these consequences become apparent immediately, I think, upon consideration of taking an average residence off the grid completely, doing the utility's job with solar and battery storage alone. Sure, a few beach shacks in the tropics can manage off the grid, but as far as I know there is not a *single* example of an average size home going off grid in the US, not without a generator or grid connection hiding behind the curtain.
I am not sure where you are getting your numbers, If the solar array shaves off the peak 50% of the usage,
and I am not net metering, my usage goes down, I think I have $7 a month grid attach fee, but besides that offset,
i would only pay for what I use at the agreed upon rate.
I agree with you that without some form of grid assist, solar is not practical for our lifestyles.
I know some off grid people, but I would not call their lifestyle normal.
we have real net zero homes, but they still draw some from the grid for motor startups and such.
 
  • #1,276
OmCheeto said:
Me too. But the stinkin' numbers keep changing on me!I was thinking about my "red-neck swimming pool under the house" idea this morning, and decided to google it.

It seems that there are red-necks in Canada.
Of course, this idea might not make sense to someone who doesn't live in or near Canada. But the principle is reversible:I see I'm not the only one who questioned how he did that. :biggrin:
I think the volume of energy is too great to store seasonally.
The University where I used to work, had a swimming pool size block of ice.
they would freeze it at night, when electric rates were off peak, and cool the buildings chilled water
system with during peak hours,but it was just day to night storage.
Tesla's power wall looks interesting, but it is expensive.
 
  • #1,277
johnbbahm said:
...swimming pool...
Olympic, or Kiddie sized?
 
  • #1,278
I remember a line from an old grade school science book where they were introducing us kids to "heat of fusion" ..
"Glauber Salt is used for heat storage because it changes phase at such a convenient temperature."
Sure enough it's in Wikipedia
https://en.wikipedia.org/wiki/Sodium_sulfate
Thermal storage
The high heat storage capacity in the phase change from solid to liquid, and the advantageous phase change temperature of 32 °C (90 °F) makes this material especially appropriate for storing low grade solar heat for later release in space heating applications. In some applications the material is incorporated into thermal tiles that are placed in an attic space while in other applications the salt is incorporated into cells surrounded by solar–heated water. The phase change allows a substantial reduction in the mass of the material required for effective heat storage (the heat of fusion of sodium sulfate decahydrate is 82 kJ/mol or 252 kJ/kg[21]), with the further advantage of a consistency of temperature as long as sufficient material in the appropriate phase is available.

For cooling applications, a mixture with common sodium chloride salt (NaCl) lowers the melting point to 18 °C (64 °F). The heat of fusion of NaCl·Na2SO4·10H2O, is actually increased slightly to 286 kJ/kg.[22]

Compare that heat capacity to water's 4.19 kj/kg. Swimming pool might get smaller .
 
  • #1,279
jim hardy said:
I remember a line from an old grade school science book where they were introducing us kids to "heat of fusion" ..
"Glauber Salt is used for heat storage because it changes phase at such a convenient temperature."
Sure enough it's in Wikipedia
https://en.wikipedia.org/wiki/Sodium_sulfateCompare that heat capacity to water's 4.19 kj/kg. Swimming pool might get smaller .

hmmm...

[google google google]
Solar Thermal Energy Storage Systems
Christopher Barile
November 28, 2010
Submitted as coursework for Physics 240, Stanford University
...
A small house (740 sq. ft.) in Boston was constructed more than 60 years ago that could be heated for up to ten consecutive sunless days. It utilized 21 tons of Glauber's salt that was stored in closets and in the partitions between walls.
...

I will have to think about this some more later, as I'm typing one-eyed. (I'm long overdue for my nap... :sleep:)
 
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  • #1,280
OmCheeto said:
Olympic, or Kiddie sized?
It has been a few years, but I think the "tank", was a box about 60 X 40 X 8 feet, so not Kiddie.
 
  • #1,281
johnbbahm said:
It has been a few years, but I think the "tank", was a box about 60 X 40 X 8 feet, so not Kiddie.
Well, if your university was as old as the one I used to work at, I'd say it was the fault of all those old buildings.
Though they did build a new one while I was there.
They claim it's pretty green.
OHSU Center First Medical Facility in Nation to Win LEED Platinum Award
02/04/08 Portland, Ore

The Center for Health & Healing blazes a trail with coveted green building certification

"It's one of the largest buildings in the country to augment forced air-conditioning with a vastly more efficient chilled beam and displacement ventilation system. All told, the energy that will be saved as a result of the buildingÍs many innovations will be nearly 5.1 million pounds of carbon dioxide a year, the equivalent of removing 443 cars from our highways."

It also has water reclamation/collection/recycling systems. Which, a hmmm, by law, had a very humorous side effect:
dontdrinkthewater.jpg


I had to google, way back then, why they had to post signs telling people not to drink from the toilets.
:oldlaugh:
 
  • #1,282
johnbbahm said:
In my area, my peak usage parallels when solar would be peaking.
looking at my usage graph from last week, my hourly Kwh usage peaked about noon at 6 kwh.
Be careful with that analysis. For residences, air conditioners tend to cycle on and off to meet the cooling load, so what may look like a continuous curve over one hour intervals may be anything but continuous over one minute intervals.
 
  • #1,283
johnbbahm said:
I am not sure where you are getting your numbers,
As we discussed earlier, if the utility billed by actual costs the connection fee should be about $100 for a $120 total monthly bill. The utility's fuel costs are 2 or 3 cents per kwh for coal and gas, 1 cent or nothing for nuclear and hydro. What do you think your kWhs are actually worth?
 
  • #1,284
mheslep said:
...nothing for nuclear...

Nuclear power is now free? :biggrin:

Unable To Compete On Price, Nuclear Power On The Decline In The U.S. [NPR]
April 7, 2016
...
But Mycle Schneider, a nuclear industry analyst, says nuclear also faces growing price pressure from wind and solar. Renewable energy is so cheap in some parts of the U.S. that it's even undercutting coal and natural gas.
...

And on a retro/necro, I still hate fracking note:
OmCheeto said:
6/29/2015
In any event, I plan on buying a lemon tree. Our water comes from above ground, out in these parts.
Just bought it last week.
 
  • #1,285
mheslep said:
As we discussed earlier, if the utility billed by actual costs the connection fee should be about $100 for a $120 total monthly bill. The utility's fuel costs are 2 or 3 cents per kwh for coal and gas, 1 cent or nothing for nuclear and hydro. What do you think your kWhs are actually worth?
You see, I am not talking about selling Kwh, but rather Kwh not purchased (I.E. Savings)
Several years ago, I added better windows, and radiant barrier,
and my electric bill went down about $100 per month
in the peak months, because I dropped almost 900 Kwh off of my peak usage.
To me, Kwh not purchased, are worth exactly what I pay for them.
 
  • #1,286
russ_watters said:
Be careful with that analysis. For residences, air conditioners tend to cycle on and off to meet the cooling load, so what may look like a continuous curve over one hour intervals may be anything but continuous over one minute intervals.
Thanks, I know that is not entirely accurate, but I think it a solar panel system were shaving
5 Kw off the top during the peak hours, it might make the curve look a lot flatter.
 
  • #1,287
johnbbahm said:
You see, I am not talking about selling Kwh, but rather Kwh not purchased (I.E. Savings)
Several years ago, I added better windows, and radiant barrier,
and my electric bill went down about $100 per month
in the peak months, because I dropped almost 900 Kwh off of my peak usage.
To me, Kwh not purchased, are worth exactly what I pay for them.
You still miss the point. The electricity grid won't work like today if everyone installs rooftop solar. Someone has to pay for it, and someone has to balance the load - which also needs money someone has to pay.
 
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  • #1,288
OmCheeto said:
Nuclear power is now free? :biggrin:...
As I suppose the grins show, the nuclear fuel is pretty close to free, with a refueling cycle cost spread over three GW-yrs of electricity sales (about a billion dollars). *Building* a nuclear plant in the US, that's not free at all unfortunately.
 
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  • #1,289
johnbbahm said:
You see, I am not talking about selling Kwh, but rather Kwh not purchased (I.E. Savings)
Several years ago, I added better windows, and radiant barrier,
and my electric bill went down about $100 per month
in the peak months, because I dropped almost 900 Kwh off of my peak usage.
To me, Kwh not purchased, are worth exactly what I pay for them.
I'm not talking about selling power back either at this point. Yes I understand one can save money under the *current* residential utility pricing system, by better home energy efficiency or by producing your own via PV.

Do you understand that, despite the current bill pricing, producing one more kWh actually costs the utility only a couple cents? That is, from the average home they need to collect that average bill of $100 to $120 a month to keep the grid going, regardless of how much PV sits on the roof. Install enough PV across the country, and that effective PV subsidy will have to go away.

In California, I've read that for every GW of new rooftop solar installed, the utilities lose $70 million a year in billings that they have to collect from somewhere (or someone) else.
 
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  • #1,290
mheslep said:
the nuclear fuel is pretty close to free,
from http://www.nei.org/CorporateSite/media/filefolder/Policy/Papers/Nuclear-Costs-in-Context.pdf?ext=.pdf
upload_2016-5-18_15-44-47.png


The utility pays its monthly neutron bill to nuclear fuel peddlers of around 0.7 of a cent per kwh
The bankers get closer to 0.9 of a cent to pay back principal plus interest
Two cents to staff, run and maintain the plant
vicinity of three and a half cents per kwh, out the switchyard door.

A lot of statistics here
http://www.eia.gov/tools/faqs/faq.cfm?id=19&t=3
It takes you to this page with cost breakdowns.
Utility's monthly fossil fuel bill is closer to 3 cents per kwh, 4X nuke .. Add to that finance , operation and maintenance and fossil runs about 4 cents.
That's what kwh's are worth.

Nuke run well still has a slight edge and that's why we keep them going.
Most of them are so old they long ago paid for themselves , so they can be moneymakers.

old jim
 
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  • #1,291
jim hardy said:
That's what kwh's are worth.
That is what you have to pay to get reliable power generation. Paying more for less reliable power costs a lot of money.
 
  • #1,292
mheslep said:
I'm not talking about selling power back either at this point. Yes I understand one can save money under the *current* residential utility pricing system, by better home energy efficiency or by producing your own via PV.

Do you understand that, despite the current bill pricing, producing one more kWh actually costs the utility only a couple cents? That is, from the average home they need to collect that average bill of $100 to $120 a month to keep the grid going, regardless of how much PV sits on the roof. Install enough PV across the country, and that effective PV subsidy will have to go away.

In California, I've read that for every GW of new rooftop solar installed, the utilities lose $70 million a year in billings that they have to collect from somewhere (or someone) else.
I understand the negative economics caused from net metering, and why the utilities are pushing back.
Net metering is effectively ordering a retailer (the utility) to buy the product they sell, at the same price they sell it for.
It is an untenable position.
In my area, the grid is maintained by a separate company, than the electrical provider, and the grid costs show up as a line
item called "TDU Delivery Charges ACTUAL PERIOD 1199 kWh @ $0.038791" billed by the Kwh for the grid,
there is also a fixed meter charge of $5.47.
I strongly suspect, as more people go to solar, they will change how this is billed to a fixed connection fee.
I think it is already happening in some states.
Under the current structure, I am billed by usage, If my usage decreases, my bill decreases by the amount I pay
for each Kwh.
 
  • #1,293
mfb said:
You still miss the point. The electricity grid won't work like today if everyone installs rooftop solar. Someone has to pay for it, and someone has to balance the load - which also needs money someone has to pay.
You are correct, the current billing method (by usage) will not be sustainable with a high number of solar users.
I suspect the grid operators already know the average cost per home for grid attachment.
The push back by utilities has been well documented, and while unpopular, is justified.
https://www.greenbiz.com/article/utilities-push-back-against-solar
 
  • #1,294
johnbbahm said:
I strongly suspect, as more people go to solar, they will change how this is billed to a fixed connection fee.
That, or something else. Whatever they change to, it will reduce the cost savings you get from rooftop solar.
 
  • #1,295
mfb said:
That, or something else. Whatever they change to, it will reduce the cost savings you get from rooftop solar.
It could go ether way, it depends on where you start!
If Nevada's new charge of $38.51 is the fixed cost, That is less than I pay for my grid usage most months.
 

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