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CPUC Nem 3.0 discussion as it relates to Energy Products

Family of 4. Everything at home is electric/heat pumps, NG service turned off a few years ago.

Last year (2021) we used 1520kWh for air cooling, 1874 kWh for home heating, and last 12 months ~1700 kWh for hot water heater for showers/dishwasher/laundry (most of that used around winter months). We set AC at ~78°F in summer.
How often does your auxiliary heat run? (I'm guessing heat strips because if your NG service is shut off, it can't be dual fuel unless you have a propane tank)
 

iPlug

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Sep 14, 2019
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Rocklin, CA
How often does your auxiliary heat run? (I'm guessing heat strips because if your NG service is shut off, it can't be dual fuel unless you have a propane tank)
Our variable speed central air-ducted heat pump lets us watch in real time equipment operating status including at what variable percent the compressor is working. We have never gotten close to needing auxiliary heat. Last year (2021) of the 1874 kWh we used for heat pump home air heating, only 7kWh was used from electric resistance heat. However, all of that 7 kWh was to defrost the coils on the coldest winter pre-dawn mornings.

Heat pump hot water heater? That's a lot of energy.
Ashamed to concur (and provided the guess-o-meter on our heat pump unit is fairly accurate).

I'm the Grinch in the family, probably only 10% of that is attributable to me. But I struggle to convince the spouse and 2 kids to keeping close to 5 minute showers. We usually shower twice daily and go through a ton a laundry with kids active in sports. I advocate to use cold water cycles for laundry, but veto power is routinely exercised on that too.

Family gives the "but we have solar" argument. I try to explain the grid is not a battery unto itself, but alas I am just rambling dad.
 

ohmman

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I'm the Grinch in the family, probably only 10% of that is attributable to me. But I struggle to convince the spouse and 2 kids to keeping close to 5 minute showers.
I have long considered a wifi valve device put inline with the hot water heater that could be controlled via an app on a parent’s phone. When triggered, it would gradually turn the hot water off. Maybe over a 3 minute period, signaling to the teen in the shower that it’s TIME TO GET OUT.
 
Our variable speed central air-ducted heat pump lets us watch in real time equipment operating status including at what variable percent the compressor is working. We have never gotten close to needing auxiliary heat. Last year (2021) of the 1874 kWh we used for heat pump home air heating, only 7kWh was used from electric resistance heat. However, all of that 7 kWh was to defrost the coils on the coldest winter pre-dawn mornings.
Did you go with electric auxiliary heat instead of a gas furnace to avoid minimum bill charges on gas? Currently I am looking at installing a dual fuel system and my water heater still runs on gas. And I probably won't get a heat pump water heater until they do the sensible thing and put the evaporator and compressor unit outside the house so it doesn't make so much noise inside. You can easily hear a compressor running in the garage but not one that's outside.
 

getakey

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Jan 28, 2020
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I don’t see why it’s so complicated. NEM 2.0 forced you into a TOU plan which already encourages adding a battery unit because of the huge cost discrepancy between on and off-peak rates. If they’re so worried about payback and equity then, IMHO, they should have a scaled payback structure where the homeowner is compensated at the tiered retail rate until they hit net-zero. Then all energy that goes into the grid after that is either purchased for wholesale rates or just nothing. That gets the solar homeowner a decent ROI, further encourages the purchase of storage systems since you’re not significantly rewarded for overproducing which helps offset peak grid use / provides resilience, and the “free” energy donated to the utility is theirs to sell for profit. Ideally, they would use this “free” money to lower rates, at least during solar generating periods, which would then provide equity for those who can’t afford or can’t purchase a solar system for whatever reason... Win-win.
thats basically how it works now in CA. Once you hit net zero, you get compensated at the wholesale rate
 

iPlug

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Sep 14, 2019
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Rocklin, CA
Did you go with electric auxiliary heat instead of a gas furnace to avoid minimum bill charges on gas?
We had NG turned off at the meter a few years ago but that was not the main reason. We did hope to avoid minimum NG bill charges, but that was mostly a wash as California perversely gives one of the clean energy rebates through having NG service which mostly erased the benefits of losing that charge.

The main reason for us was that we wanted to be 100% electric for home, vehicles, yard equipment, etc as are working towards minimizing our carbon footprint. Have been hoping for home batteries for a while, but barriers are if prices improve and if it looks like we will stay in the house for more than a few more years.

Currently I am looking at installing a dual fuel system...
Your sig says SF bay area. Your winters likely are even more mild than ours (we don’t get more than a very brief light snow every few years and freezing temps are not particularly common nor have I seen if colder than 25°F and only below freezing temp some winter days for a few hours before dawn). I would recommend you consider not going the dual fuel route.

...my water heater still runs on gas. And I probably won't get a heat pump water heater until they do the sensible thing and put the evaporator and compressor unit outside the house so it doesn't make so much noise inside. You can easily hear a compressor running in the garage but not one that's outside.
This would certainly help with noise inside, but you would lose efficiency by moving it outside and it would also be more prone to rusting. We run our heat pump water heater only during off-peak hours. That also means running it sometimes when it is quite chilly outside, but invariably it is much warmer in the garage then.

Consider working on sound isolation such as a sound dampening board under the water heater to attenuate sound conduction through direct solid material contact and consider sound isolation material on the wall(s) adjacent to the water heater for air transfer acoustic attenuation.

We haven't done any sound isolation and agree the heat pump water heater can be heard on the opposite wall inside the house. It's white noise, so not particularly annoying. Still, ours is against a master bathroom wall and we can only hear it quietly from the master bedroom with the door to the bathroom open.
 

stopcrazypp

Well-Known Member
Dec 8, 2007
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Does that mean you get $2/kWh when wholesale rates happen to go that high?
No, it's 12 month rolling average which was like $0.04/kWh on my latest statement and calculated at your annual true-up statement.
This link has the numbers for the various utilities (under section for Net Surplus Compensation):
Net Energy Metering

The PG&E one is dead, but I found the current link in google:
https://www.pge.com/pge_global/comm...s/green-energy-incentives/AB920_RateTable.pdf

Even with current surging prices, the latest amount for September is only $0.05382/kWh.
 
Does that mean you get $2/kWh when wholesale rates happen to go that high?
I'm a net producer and get compensated at ~$0.03-$0.04/kWh for my excess production no matter what the wholesale prices are. I adjusted my thermostat down to 76F this summer since it is worth the small amount I loose in compensation.

I'm at 2100' altitude and definitely use more total energy in the winter but I have a dual fuel (propane) system (as well as a woodstove). I ran the numbers when I was building my house (late 2000's) and the ROI barely penciled out for dual fuel then when everything was being installed from scratch. If you are considering installing dual fuel for cost savings I'd definitely run the numbers to see if it makes sense.
 
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holeydonut

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I have long considered a wifi valve device put inline with the hot water heater that could be controlled via an app on a parent’s phone. When triggered, it would gradually turn the hot water off. Maybe over a 3 minute period, signaling to the teen in the shower that it’s TIME TO GET OUT.

A divorce is gonna be way more costly than the savings from shorter showers...
 
Your sig says SF bay area. Your winters likely are even more mild than ours (we don’t get more than a very brief light snow every few years and freezing temps are not particularly common nor have I seen if colder than 25°F and only below freezing temp some winter days for a few hours before dawn). I would recommend you consider not going the dual fuel route.

I'm at 2100' altitude and definitely use more total energy in the winter but I have a dual fuel (propane) system (as well as a woodstove). I ran the numbers when I was building my house (late 2000's) and the ROI barely penciled out for dual fuel then when everything was being installed from scratch. If you are considering installing dual fuel for cost savings I'd definitely run the numbers to see if it makes sense.
I have an existing gas furnace. The gas hookup is already there. And the quote I got for the 80 AFUE furnace is cheaper than the quote for an air handler plus heat strips, which would be a few hundred dollars more, believe it or not. I'm not sure if that's because they'd have to install 240V power to the air handler and heat strips or if gas furnaces are just that cheap, but that's the quote I got. Dual fuel is more flexible and has a lower carbon footprint too, assuming the electricity is being generated by fossil gas at the power plant. Is that a good assumption on the coldest nights (no sun, calm wind)? I think so, until we start using nuclear breeder reactors, but those should kick in after we have plenty of storage because they can't ramp up and down quickly like fossil gas plants can. So anyway, my conclusion is that dual fuel is probably better for the environment, regardless of what the people at CARB just said about gas furnaces.

Regardless of whether I go with a gas furnace or heat strips though, I don't expect either one to operate very much. However, at least dual fuel gives me the option of using gas to heat if it's less expensive than electricity. I would get an external sensor on my thermostat and set it to switch over to gas if the outdoor temperature drops below the point where the heat pump's COP isn't good enough to be cheaper than gas (currently, on ETOU-D and in tier 1 for gas, the crossover point is around 45°F). I expect that this temperature would change from year to year as rates fluctuate but I created a spreadsheet that I can put peak and off peak rates and tier 1 and 2 rates for gas and it will spit out the heat pump COP I need to make electricity cheaper than gas. And then I simply need to refer to the product data charts for the heat pump to find the crossover temperature.

This would certainly help with noise inside, but you would lose efficiency by moving it outside and it would also be more prone to rusting. We run our heat pump water heater only during off-peak hours. That also means running it sometimes when it is quite chilly outside, but invariably it is much warmer in the garage then.
Well ideally, compressor and one evaporator outside, and another evaporator either in the garage or in the house (for times you want the house cooled). There are reasons to take heat from the house or garage but doing it when you need the house heated is counterproductive.
 
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iPlug

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Sep 14, 2019
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Rocklin, CA
I have an existing gas furnace. The gas hookup is already there. And the quote I got for the 80 AFUE furnace is cheaper than the quote for an air handler plus heat strips, which would be a few hundred dollars more, believe it or not. I'm not sure if that's because they'd have to install 240V power to the air handler and heat strips or if gas furnaces are just that cheap, but that's the quote I got. ...
Agree, you might be able to take advantage of current and future price arbitrage with a dual fuel system if economics are the primary driver and continue to pencil out.

NG historically has been cheap for many years. But with current and future forecast LNG prices/demand and US LNG exports increasing to meet that demand, that will likely squeeze US NG prices a lot over the next few years and the utilities will pass that on to us.

...Dual fuel ... has a lower carbon footprint too, assuming the electricity is being generated by fossil gas at the power plant...
We were concerned about that possibility but in our case (PG&E) + home solar PV that proved to be far from the case:

PG&E 2021 electric power mix

en-powermix.png

....
 
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holeydonut

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I didn't realize that nuclear was such a large portion of PG&E's power.


Yeah, here's the report that iPlug took the image from:

Knowing what significant mix Diablo Canyon plays to PG&E generation sources, also remember that Todd Strauss, PG&E’s senior director of energy policy planning said that PG&E would not provide anyone with a detail of new expected energy sources to offset Diablo Canyon shuttering in 2024/2025.

In his words...

"If I try to write down megawatt-hour by megawatt-hour what fills that gap in 2025 right now, that’s actually a losing strategy... The proposal clearly recognizes there’s lots of other things that need to be done, but we shouldn’t specify it today."

"Today" in his quote was 2017. So literally PG&E said they wanted to replace Diablo Canyon with clean energy but never once actually published a plan for public consumption describing how to achieve that goal. And to my knowledge It's now 2022 and PG&E still hasn't specified what was their plan to offset Diablo Canyon capacity at night, in the daytime, etc etc. Is it a shocker to anyone that they just asked Newsom to throw a bunch of forgivable loans at the problem so they can keep running Diablo Canyon?

 

iPlug

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Sep 14, 2019
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Rocklin, CA
I didn't realize that nuclear was such a large portion of PG&E's power.
Yes, Diablo Canyon is the only nuclear plant in California and PG&E owns it and takes (it appears full) accounting credit for it.

Offshore wind is planned nearby in Morro Bay in a few years. Nice that will be able to feed into existing high voltage transmission lines at Diablo Canyon.


The California Energy Commission (CEC) adopted a report... set planning goals of 2,000-5,000 megawatts (MW) of offshore wind by 2030 and 25,000 MW (25 GW) by 2045, enough electricity to power 3.75 million initially and 25 million homes by mid-century.
There are currently two federally-designated wind energy areas (WEAs) off the cost of California: Humboldt off the North Coast and Morro Bay off the Central Coast...
...Additional transmission infrastructure will be needed to deliver offshore wind energy from this region to the grid. Existing transmission on the Central Coast is robust and near large load centers. Near-term electric generator retirements, such as 2,225 MW from the Diablo Canyon Nuclear Power Plant, provides an opportunity to repurpose existing infrastructure to integrate wind energy developed offshore the Central Coast, the report says...

California Energy Commission adopts offshore wind goals: 5GW by 2030, 25 GW by 2045
 
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iPlug

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Sep 14, 2019
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Rocklin, CA
Diablo is only 10% of Calif ISO. But still closing Diablo leaves a large gap in supply
It was set to close in 2025 but within recent months legislature has been pushing to keep it open five years longer. Diablo Canyon produces 2,250MW, nearly 9% of California's electricity last year and ~15% of the state's clean energy production.

But as mentioned a couple posts ago, most of this will be covered. The California Energy Commission is planning 2,000-5,000 MW of offshore wind by 2030 and 25GW by 2045. Aside from this, increasing amounts of utility scale and residential combined solar PV + grid battery storage will continue to roll out for many years to come.
 
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