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CPUC Nem 3.0 discussion as it relates to Energy Products

h2ofun

Active Member
Aug 11, 2020
4,123
1,071
auburn, ca
Can you elaborate on what the issue is? My NEM idea doesn't preclude this scenario. If they have an electric house, they're still covered under their solar investment until they hit net-zero. Keep in mind that they might not have enough panels or battery-storage to hit net-zero so their solar system may only just reduce, not eliminate, their electric bill.
I bank thousand of dollars during the summer with PGE. This allows me to use these credits during the winter with my 30kw solar only produces 5kw for the day, but I use 100kw to heat my house.
 
I bank thousand of dollars during the summer with PGE. This allows me to use these credits during the winter with my 30kw solar only produces 5kw for the day, but I use 100kw to heat my house.
Are you NEM1 or NEM2? I'm waiting for Pacific Gouge & Extort to yank the E-1 plan from underneath everyone on NEM1 by simply discontinuing that rate plan and only offering TOU plans.
 
I bank thousand of dollars during the summer with PGE. This allows me to use these credits during the winter with my 30kw solar only produces 5kw for the day, but I use 100kw to heat my house.

Ah gotcha, that's easy enough to cover as there is a 12 month true-up period. I should have clarified that I didn't intend for people to meet net-zero on a month-to-month basis, but on a rolling basis over some set period of time (say 12 months). Aside from covering seasonal usage, a rolling period makes sense because some months are just better than others - the goal is to look at an aggregate picture, not a micro-view of just a single month.
 
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ohmman

Upright Member
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Feb 13, 2014
11,285
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North Bay, CA
Ah gotcha, that's easy enough to cover as there is a 12 month true-up period. I should have clarified that I didn't intend for people to meet net-zero on a month-to-month basis, but on a rolling basis over some set period of time (say 12 months). Aside from covering seasonal usage, a rolling period makes sense because some months are just better than others - the goal is to look at an aggregate picture, not a micro-view of just a single month.
The "problem" with the 12-month true-up, from the utilities' point of view, is that as solar adoption continues, they will find themselves in a surplus situation in the summer months. The eventual outcome will be far too much power on the grid and people banking credits for the winter months. I suspect the solution to this would be to just keep tweaking the TOU rates to make daytime power in the summer close to free, all the way to 6pm or whatever time the demand curve outpaces supply. Off-peak might go from 8am-6pm instead of overnight. Then, backfeeding to the grid will provide owners with no real benefit and no way to bank through to winter. It will also solve the equity situation since people without solar will be getting very inexpensive power for a long stretch in the summer.

Winter TOU rates would likely be.. unpleasant.
 
Winter TOU rates would likely be.. unpleasant.

Certainly possible, but NM wind that blows at night and will be exported to CA, as well as up and coming off-shore wind are large night-time inputs. IIRC the Zia transmission line to AZ (and from there to CA) is 3 GW

And I hope NM is just getting started. We have about 500 GW (Yes -- Gigawatts) of commercially exploitable resource. Current state use is about 7 GW, so I figure that will jump to 14 GW as the car fleet is changed to EV.

My issue with CA is that it is kind of a small market
Just kidding
 
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@ohmman I suspect you’ll likely be right. When I did the math, best ROI was to overproduce and buy more panels, but I opted to divert budget for storage because I suspect exactly that - that the utilities will keep tweaking TOU rates which changes the math. Only bought one battery for now as it’ll cover me for up to 13 hrs under current usage.

For those that use electric heaters - I think they’re just going to have to either get used not not negating their whole electric bill or buy more batteries. Those with AC have the same problem in the summer - they suck up a lot of power. At least, in my case, I’ve already accepted that I can potentially offset near everything but my AC - not worth buying another battery or two in my case, but each person has different needs.

This is going to get interesting as didn’t CA just ban gas for new construction?
 

aesculus

Still Trying to Figure This All Out
May 31, 2015
5,017
2,922
Northern California
I personally believe the standard for net zero homes is bogus. From what I can see it's based on a yearly basis. So I could be a complete energy hog during the winter and create a bunch of energy during the summer and offset my kWh to zero and qualify.

That does not really help. Because the utilities have to have enough energy on hand to satisfy my winter demand. Most power plants cannot pay for themselves by being idle for 6 months of the year. So you end up with having a limit on whatever alternatives you can provide that are not flat (ie base loads). Its a complex equation and not consistent across all geographies.

To me, a net zero home should really be one that is zero on a daily average. Even better if it's self contained with batteries. And there are techniques that can help ride the daily usage curve like consuming energy during higher solar production (ie charging cars during sunlight hours) or building thermal mass into homes to smooth heating/cooling demand (thermal flywheels).

I think the industry is still a ways off from figuring this all out. And while they may be getting pretty close for new construction, that's just the tip of the iceberg considering all the existing buildings that are way out of compliance.
 
I’m curious, let’s say that NEM 3.0 ends up being some Draconian thing - is it possible to stay connected to the grid, turn off export, and just not participate in net metering? Use what you farm, invest in batteries, pay for the rest, sell nothing.

This doesn’t solve the power company’s issue of the potential of higher peak demand, but if this is done do they have any say or right to tax you on what’s happening behind the meter if it stays behind the meter?
 

holeydonut

Active Member
Supporting Member
Jun 27, 2020
3,659
3,175
East Bay NorCal
I’m curious, let’s say that NEM 3.0 ends up being some Draconian thing - is it possible to stay connected to the grid, turn off export, and just not participate in net metering? Use what you farm, invest in batteries, pay for the rest, sell nothing.

This doesn’t solve the power company’s issue of the potential of higher peak demand, but if this is done do they have any say or right to tax you on what’s happening behind the meter if it stays behind the meter?

Yeah I thought a non-exporting solar was the solution too… but I think WWhitney posted that having a system that was in any way running in parallel with the grid would follow Rule 21 guidelines. So in that case even if the PV+ESS system was set up to be “non grid exporting” it would need an interconnection agreement and then you’re looking at the $8 per KW AC per month solar tax.

I was speaking with someone at Enphase and they said a lot of installers were investigating relocating specific critical loads to a completely off grid configuration when paired with ESS.

For example imagine your kitchen, bedrooms, and family room breakers relocated to a new micro grid that was only powered with solar and ESS. Since it’s not tied to the grid at any time, it wouldn’t be affected by Rule 21.

This example system may use 5,000 kWh per year and the goal is to size the PV and ESS so it covers year round energy needs even in the worst case winter month. There would be no NEM at all. And of course such a system would still be more economical to the homeowner than the NEM 3 PD.

One trump card in all this is if a bidirectional EVSE could be installed. So the homeowner could in a pinch drive to a supercharger, load up the mondo battery in the vehicle, then drive back home to power the house. This would allow a much more efficient solar array sizing since the micro grid would have two potential sources (solar and EV).
 
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I’m curious, let’s say that NEM 3.0 ends up being some Draconian thing - is it possible to stay connected to the grid, turn off export, and just not participate in net metering? Use what you farm, invest in batteries, pay for the rest, sell nothing.

This doesn’t solve the power company’s issue of the potential of higher peak demand, but if this is done do they have any say or right to tax you on what’s happening behind the meter if it stays behind the meter?

NEM3.0 will most likely be pretty bad and much worst than 2.0/1.0, but that's to be expected at this point.

I think if you're connected to the grid in anyway, I feel that the utility has a right/etc to charge folks for being able to tap the grid when things are bad for the solar home owner. You see so many posts about no battery storage on-site because the grid is my massive battery, why waste $$ and there is no ROI, etc.... In a way, that's very true since it's hard to make numbers work for a battery home system under current NEM/battery costs.

I feel though, that's sorta unfair to take our cake (no power bills) and eat it too (get grid power if I have no solar).

I don't feel it's that easy to completely go off grid due to heating. It's very possible to have days of no solar so putting it all on solar/storage is not going to cut it IMO and folks who want to cut the grid need most alternative fuel options. I "personally" wouldn't worry about the environment, but that's me if one really wanted to go off-grid (not like I want stinky stuff neither, but beggars can't be choosers if one were to seriously go offgrid...I'd definitely like to hear more tech options though...The car EV is a good one and I hope companies start really launching stuff in a few years).

Folks really still need some other form of fuel if you have a week of cloudy days, a wild fire that blocks all sun, etc...
 
The "problem" with the 12-month true-up, from the utilities' point of view, is that as solar adoption continues, they will find themselves in a surplus situation in the summer months. The eventual outcome will be far too much power on the grid and people banking credits for the winter months. I suspect the solution to this would be to just keep tweaking the TOU rates to make daytime power in the summer close to free, all the way to 6pm or whatever time the demand curve outpaces supply. Off-peak might go from 8am-6pm instead of overnight. Then, backfeeding to the grid will provide owners with no real benefit and no way to bank through to winter. It will also solve the equity situation since people without solar will be getting very inexpensive power for a long stretch in the summer.

Winter TOU rates would likely be.. unpleasant.
They really need to just let retail rates float along with the wholesale rates. PG&E already has devices that can show you exactly what you're paying at any given time. They could probably do a combination of fixed rates and floating rates by announcing rates 24 hours in advance, and while they won't exactly reflect wholesale rates, they'll probably be close (and update the devices to show the rates for the next 24 hours). That way, people's smart thermostats could come up with a schedule for the next 24 hours and would know when to precool and when to shut off the HVAC to try to maintain a comfortable environment for the lowest cost. This will automatically solve the issues with supply in the evenings because people will have a financial incentive to conserve during those times, and if it's integrated into smart thermostats and happens automatically, you won't have to do anything except set it and forget it. This would be very different from what was happening in Texas with Griddy, where people were exposed to wholesale rates but just weren't told anything about what they were until the bill came at the end of the month.

Tesla could also easily integrate floating rate capabilities into their cars, and I'd be able to set my vehicle to charge to say 40% whenever it's cheapest to do so. Then you can tell the vehicle, if the rate goes below $x/kWh, charge to 50%. If it goes below $y/kWh (y < x), charge to 60%. And so on. It would likely also spur development of new HVAC systems that chill water in a large holding tank during the day, and then shut down the compressor and use the water to cool your house during the time when electricity costs the most.
 
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The "problem" with the 12-month true-up, from the utilities' point of view, is that as solar adoption continues, they will find themselves in a surplus situation in the summer months. The eventual outcome will be far too much power on the grid and people banking credits for the winter months. I suspect the solution to this would be to just keep tweaking the TOU rates to make daytime power in the summer close to free, all the way to 6pm or whatever time the demand curve outpaces supply. Off-peak might go from 8am-6pm instead of overnight. Then, backfeeding to the grid will provide owners with no real benefit and no way to bank through to winter. It will also solve the equity situation since people without solar will be getting very inexpensive power for a long stretch in the summer.

Winter TOU rates would likely be.. unpleasant.
Extending this to a conversion of electric A/C and gas heating to all electric heat pump will shift the equation further, but I'm not sure how this would fully play out. If heat pump HVAC systems are a lot more efficient then maybe we get to a uniform rate structure year round as the demand during the summer reduces and the demand during the winter increases.
 

ohmman

Upright Member
Global Moderator
Feb 13, 2014
11,285
22,247
North Bay, CA
Extending this to a conversion of electric A/C and gas heating to all electric heat pump will shift the equation further, but I'm not sure how this would fully play out. If heat pump HVAC systems are a lot more efficient then maybe we get to a uniform rate structure year round as the demand during the summer reduces and the demand during the winter increases.
Yeah, I really don't know what that would look like, but I suspect that we'd still see a surplus supply in summer compared to winter, especially as people move from natural gas to heat pumps for heating and new construction has that mandated. Electricity demand in winter will go up, solar generation goes down naturally. Add to that more EVs on the road using more energy in winter... but who knows for sure. Maybe climate change will reduce winter heating load but increase summer AC load which would work in favor of the additional solar.
 
They really need to just let retail rates float along with the wholesale rates. PG&E already has devices that can show you exactly what you're paying at any given time. They could probably do a combination of fixed rates and floating rates by announcing rates 24 hours in advance, and while they won't exactly reflect wholesale rates, they'll probably be close (and update the devices to show the rates for the next 24 hours). That way, people's smart thermostats could come up with a schedule for the next 24 hours and would know when to precool and when to shut off the HVAC to try to maintain a comfortable environment for the lowest cost. This will automatically solve the issues with supply in the evenings because people will have a financial incentive to conserve during those times, and if it's integrated into smart thermostats and happens automatically, you won't have to do anything except set it and forget it. This would be very different from what was happening in Texas with Griddy, where people were exposed to wholesale rates but just weren't told anything about what they were until the bill came at the end of the month.
A lot could be done with optimizing the current HVAC operation. Heat pump efficiency goes down as the difference between outside temperature and inside set temperature increases. Sometimes it is better to use a temperature set back when an area is unoccupied but other times it is necessary to keep the unit running because it couldn't recover from a setback (or would need to use auxiliary heat when running as a heat pump). Having a system that takes weather predictions, daily temperature swings, electricity rates, flex alerts, etc. into account could increase the efficiency and economy of the system and help the burden on the grid while maintaining comfortable temperatures.
 
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holeydonut

Active Member
Supporting Member
Jun 27, 2020
3,659
3,175
East Bay NorCal
A lot could be done with optimizing the current HVAC operation. Heat pump efficiency goes down as the difference between outside temperature and inside set temperature increases. Sometimes it is better to use a temperature set back when an area is unoccupied but other times it is necessary to keep the unit running because it couldn't recover from a setback (or would need to use auxiliary heat when running as a heat pump). Having a system that takes weather predictions, daily temperature swings, electricity rates, flex alerts, etc. into account could increase the efficiency and economy of the system and help the burden on the grid while maintaining comfortable temperatures.


I just wish there was a company out there to actually help homeowners make smart energy decisions around HVAC and appliances. I am a total effing moron because I did an HVAC overhaul before I found TMC. I had been recommend someone to help me do the optimization, and now I realize I got totally jobbed because I was ignorant and stupid. And of course, searching about this stuff on Google just yields results that are spammy lead gen bullsh!t stuff to steer you toward lame azz HVAC contractors that want to sell what they stock even if it doesn't really help the homeowner.

I was able to help a neighbor spec out the system I would have put in had I had the brains back in 2019. It costs the same as what I paid and is way more efficient.

2019-Holeydonut = Dumbazz
2022-Holeydonut-after-being-on-TMC = Mildly smarter but still kind of dumbazz
 
I just wish there was a company out there to actually help homeowners make smart energy decisions around HVAC and appliances. I am a total effing moron because I did an HVAC overhaul before I found TMC. I had been recommend someone to help me do the optimization, and now I realize I got totally jobbed because I was ignorant and stupid. And of course, searching about this stuff on Google just yields results that are spammy lead gen bullsh!t stuff to steer you toward lame azz HVAC contractors that want to sell what they stock even if it doesn't really help the homeowner.

I was able to help a neighbor spec out the system I would have put in had I had the brains back in 2019. It costs the same as what I paid and is way more efficient.

2019-Holeydonut = Dumbazz
2022-Holeydonut-after-being-on-TMC = Mildly smarter but still kind of dumbazz
I've done calculations for HVAC in the SF Bay Area. It basically doesn't make sense to get anything except the most basic single stage system. We don't use enough HVAC to ever save more than the additional cost of a more efficient system before it needs to be replaced because it gets too old.
 
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holeydonut

Active Member
Supporting Member
Jun 27, 2020
3,659
3,175
East Bay NorCal
I've done calculations for HVAC in the SF Bay Area. It basically doesn't make sense to get anything except the most basic single stage system. We don't use enough HVAC to ever save more than the additional cost of a more efficient system before it needs to be replaced because it gets too old.


Eh, I disagree... variable speed heat pump are the way to go in any inland territory. Coupled with this should be an efficient heat exchanger and variable speed air handler.

Have you seen the general rate case for electricity and natural gas? Transmission and Distribution costs are going to go up almost 50% by the end of the next GRC. And with the rate at which commodity prices are changing, you can expect over 50% increases to that portion of your bill by 2027 as well.

TLDR, I still have NG furnaces and water heater because I suck.
 
Eh, I disagree... variable speed heat pump are the way to go in any inland territory. Coupled with this should be an efficient heat exchanger and variable speed air handler.

Have you seen the general rate case for electricity and natural gas? Transmission and Distribution costs are going to go up almost 50% by the end of the next GRC. And with the rate at which commodity prices are changing, you can expect over 50% increases to that portion of your bill by 2027 as well.

TLDR, I still have NG furnaces and water heater because I suck.
I disagree because eventually, retail rates will be allowed to float and will track wholesale rates. Meaning that what you want to do is run the HVAC during the day to preheat or precool (depending on the season) when electricity is cheap and then shut down the system in the evening, when the price of electricity spikes. This will negate most of the advantage of a variable speed system. Variable speed is for reducing or eliminating cycling, but in the Bay Area, the outdoor temperature crosses through our indoor set point on most days, meaning that the system cycles anyway. Variable speed systems can generally only get down to 20-30% and if the building requires less than that, the system will cycle.
 

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