Average Consumption?

[Lt.Dan]

I hear you from Paso Robles! at least here, closer to the coast, we can turn off the AC at 9pm. my bill goes up to $450. in the summer sometimes, but always in the winter. I need to find a substitute for the 1500 watt heaters my renters use.

Yeah I've stayed in RV parks in Paso and frequent Avila and Grover Beach areas. It definitely cools down at night, whereas here in the valley it does not cool off at night! I remember last year walking out to my car at 5am to drive to work and it was 85* outside ?

 

[tomy2]

Regret to inform that I may be responsible for a good percentage of that hole in the Ozone layer. Working towards mending my ways... View attachment 96768

That would cost over $1,000./month in California. what is your rate 12cents/kwh?

 

[tomy2]

Yeah I've stayed in RV parks in Paso and frequent Avila and Grover Beach areas. It definitely cools down at night, whereas here in the valley it does not cool off at night! I remember last year walking out to my car at 5am to drive to work and it was 85* outside ?

Next time you want to stay in Paso, I have nice flat private space on my property, with water and septic hookup. I've been thinking about short term renting it to RVers with solar setups. I used to rent it full time, but the electric costed half of the rent. If your interested, I could send some photos.

 

[tomy2]

Almost 20 years ago, CEC rebate allowed up to 200% of consumption, which I documented with one month's electric bill.
(Left my pool pump running 24/7 for a month straight to help document my consumption.)

Back then, PG&E limit was 10kW, maybe larger with additional review.
Today, 30kW and additional review for larger.
Somewhere I have read up to 5kW doesn't require documentation of consumption, because that is typical for a residence.

Many more pages on the topic now. Here's one:

https://www.pge.com/tariffs/assets/pdf/tariffbook/ELEC_FORMS_79-978-02.pdf

"Two hundred thousand dollars ($200,000) for each occurrence if the Gross Nameplate Rating of the Generating Facility is ten (10) kW or less and the Generating Facility is connected to an account receiving residential service from PG&E."

Also something about "waive" and "self-insure"

Assuming 5 hours average full sun, you might want 10kW of PV. (more in summer and less in winter of course.)
Assuming 5.5 hours, 10kW would give average 55kWh. 55kWh x 365 = 20,075 kWh/year

If you later over-panel with multiple PV orientations, might produce 1.4 times that much without clipping at peak.
It will be nice to have enough power for off-grid operation of A/C during power failures. Unless you have a large battery bank to save morning production for afternoon cooling, want enough PV generation to run the air conditioner. My house and central A/C aren't so large.

My neighbor has a bunch of panels, he says that it's not worth over producing because pge only pays pennies a kw.

 

[tomy2]

Regret to inform that I may be responsible for a good percentage of that hole in the Ozone layer. Working towards mending my ways... View attachment 96768

Is your wife Bit mining inher spare time?

 

[Hedges]

My neighbor has a bunch of panels, he says that it's not worth over producing because pge only pays pennies a kw.

Used to be zero, any excess was erased at trueup. Then, $0.025/kWh.

With net metering intact but peak rates shifted later in the day, overproducing meant I could deliver 3 kWh in the morning for $0.15 credit each, and receive one kWh late afternoon rather than paying $0.45; Because I could install GT PV for $1/W, my cost would be $0.025/kWh. 3 x $0.025 = $0.075 << $0.45, still worthwhile.

Beyond what credits I do consume, next point is erring on the side of too small or too large. If too small, buying an additional kWh costs $0.45 peak or $0.15 off peak. If too large, I waste $0.025/kWh. So I can err a bit on the side of too large.

Rates per kWh have changed a bit (increased and compressed to less spread between peak and off peak.)
When NEM 3.0 hits, if it reduces credit to 25% of retail, if it charges me a tax on photons equal to the credit, then none of this works.
Then only use power when produced, or possibly batteries (some server rack batteries are around $0.05/kWh now.)
The proposal has been likened to charging people for using a clothesline rather than an electric dryer because they aren't paying their fair share of the grid. Remains to be seen if we will be charged for off-grid and zero-export systems.

 

[tomy2]

Used to be zero, any excess was erased at trueup. Then, $0.025/kWh.

With net metering intact but peak rates shifted later in the day, overproducing meant I could deliver 3 kWh in the morning for $0.15 credit each, and receive one kWh late afternoon rather than paying $0.45; Because I could install GT PV for $1/W, my cost would be $0.025/kWh. 3 x $0.025 = $0.075 << $0.45, still worthwhile.

Beyond what credits I do consume, next point is erring on the side of too small or too large. If too small, buying an additional kWh costs $0.45 peak or $0.15 off peak. If too large, I waste $0.025/kWh. So I can err a bit on the side of too large.

Rates per kWh have changed a bit (increased and compressed to less spread between peak and off peak.)
When NEM 3.0 hits, if it reduces credit to 25% of retail, if it charges me a tax on photons equal to the credit, then none of this works.
Then only use power when produced, or possibly batteries (some server rack batteries are around $0.05/kWh now.)
The proposal has been likened to charging people for using a clothesline rather than an electric dryer because they aren't paying their fair share of the grid. Remains to be seen if we will be charged for off-grid and zero-export systems.

I can't see them charging for off grid, only because it would be hard to measure. I'm putting together an off grid system that will only cut my bill in half. I can do more later if this works out. I see a problem with my design, it calls for a 60 amp breaker in a 40amp subpanel. Could you look at it and see if you agree. thanks

 

[Hedges]

You can have a inverter that switches between grid/solar to support a downstream load, or blends up to 100% of PV plus extra from grid, as your diagram shows.
Better would be grid tie zero export, backfeeding to your house but with CT to sense and prevent power backfeed to grid.

California's NEM 3.0 proposal as adopted by PUC was to credit backfeed 25% of retail (therefore $0.05/kWh during middle of the day) and charge $8/kW/month fee for PV capacity (therefore $0.05/kWh whether used locally or backfed. Or not produced on a cloudy day.)

As written, it said nothing about what PV and inverter were connected to. Presumably, if you had an off-grid PV system and could switch to grid at night (or even if you couldn't switch), letter of the NEM 3.0 policy would charge you. Just the same as a clothesline, except it was in terms of kW not thermal energy.

 

[Rednecktek]

I can't see them charging for off grid, only because it would be hard to measure.

You have 4.5Kw of panels installed? That's a 4.5Kw tax and surcharge.

 

[brasscow]

I just flipped the switch on my solar a bit over a week ago. Here's my rolling last month's usage:



The low usage days there around 5/27 are days where I was experimenting with it on and off and turning it off and moving batteries and what-not.

I am still attached to grid but have sol-arks zeroing it out.

 

[Hedges]

I see a problem with my design, it calls for a 60 amp breaker in a 40amp subpanel. Could you look at it and see if you agree. thanks

I don't see "40 amp subpanel" labeled.
I do see "40 amp breaker" feeding, so that would be the current limit.
I don't understand the purpose of extra panel with 60A breaker, would just run wire from main panel. 60 A and 6 awg.

"4.0 wire" and "6.0 wire" aren't designations I recognize. "8 gauge" I do.
The wire to batteries will be at lower voltage therefore higher current than the AC wires.

For 40A, use 8 awg. For 60 A use 6 awg. For 30 A use 10 awg. (Or heavier gauge, which is a smaller number gauge)

https://www.usawire-cable.com/pdfs/nec%20ampacities.pdf

Note the "**" next to 14, 12, 10 awg. That says to operate at reduced current, don't actually use the ampacity shown in chart.

Inverter data sheet suggests 30A breaker on output, 60A on input because it could be charging battery while also bypassing power to output.
It suggests10 awg, which would only be for the 30A output, need 6 awg for 60A input.

https://signaturesolar.com/content/documents/EG4/EG4%203000EHV-48%20Inverter%20Users%20Manual%20-%20Final%20RevA%20with%20WiFi%20Startup.pdf

"125A load panel"
OK to use a panel rated for that much current, but inverter will only deliver 25A. Smaller panel OK if enough slots.
Inverter is 120V single phase. That could mean using only every other breaker position in panel, or wiring to feed both phases. But that is difficult while also including a 30A breaker in the panel. I could come up with ways to do it.

You won't find a panel with 30A main breaker. The wires from inverter to breaker panel will be hot, so it is undesirable to have them land on a branch circuit breaker which could pop out and have exposed hot contacts. There are kits which secure a branch circuit breaker with straps (e.g. generator backfeed kits.) Using one of those has the advantage that you can bypass inverter if it fails and feed the sub-panel from main panel instead.

2, 15A and 2, 20A breakers consume 4 slots (or 2 slots if tandem breakers used.)

Here's a panel that I think would do everything you need. I use one. Expensive at $200 (a bit less elsewhere) but quality and all functions desired.

Square D QO 30-Amp 4-Space 8-Circuit Generator Main Breaker Outdoor Manual Transfer Switch QO1DM10030TRBR - The Home Depot

The Square D by Schneider Electric QO 30/100 Amp 4-Space 8-Circuit Temporary Transfer Generator Panel helps you change from utility power to a standby source with the flip of 2 QO main circuit breakers.

www.homedepot.com

I would feed one pole of the 100A breaker with 6 awg from 60A breaker in main panel. Neutral bar 6 awg from main panel. Ground with appropriate gauge (could be 6 awg or a smaller gauge, left as exercise for reader)

I would feed one pole the 30A breaker from output of inverter.

Because this is 120V only, not 120/240V, I would run 6 awg wire between the lugs of L1 and L2 busbar in panel.

Inverter input I would feed from same 60A run coming from main panel to this sub panel. Neutral and Ground use busbars in panel. The only trick is hot Line, because you aren't supposed to put two wires in the screw terminal of 100A breaker. So I would splice two wires together with a split-bolt.




Now, all 4 remaining slots in the panel are available for branch circuits, all connected to same 120V source.
Source can be either inverter output or grid (main panel), with interlock to safely select between them.
Output of inverter is protected at 30A.
Input of inverter is protected at 60A.
If inverter fails, just flip interlocked breakers to bypass.

Only catch is, when failed inverter is bypassed, the input wires to inverter are still hot. Have to turn off 60A breaker while unmounting inverter, and cap wire ends before turning breaker back on.

Here's mine.
The black lumps are split-bolt splices, wrapped in rubber tape and vinyl tape. (Inverter output can backfeed this panel and one other.)
I replaced 100A/30A breakers with 70A/70A. The lugs feed house, and two breakers select either grid or inverter as source.
The unused generator plug has its wires in ground bar. Have since replaced with an outlet fed by GFCI breaker.

 

[tomy2]

Because this is 120V only, not 120/240V, I would run 6 awg wire between the lugs of L1 and L2 busbar in panel.
Can't I just do this with the load panel I have? There will be no wires at the lugs, all the power will come from the 30 amp breaker. I don't really like this, but that's the way the manual says to do it, and I ordered a clamp to hold the breaker in place. Now I wonder if that breaker should be a certain type, since the current is running backwards?
thanks for the pictures and recomend panel, but that looks too complicated for me. I made some changes in my diagram also. I now see that it still shows a 40 amp breaker in the main, that should be a sixty amp 2 pole feeding the subpanel. There is also a 2 pole 40 amp breaker for the Air compressor in that subpanel.

 

[Hedges]

There is probably a way to use both poles of your panel for the same 120V line (instead of 120/240V split phase)
If it is a big enough panel, you can just use one pole, leave every other slot empty.
What you can't do is feed inverter single-phase 120V output into two poles of a 30A breaker, because 2 x 30A = 60A, too large to protect inverter relay and wiring.
Need to feed through a single pole 30A, then spread to both poles in panel (if you want to use both.) I suggested wire between lugs. Could instead install a 2-pole breaker and wire its lugs together.

With AC, current alternates so isn't running "backwards". Only issue is exposed conductors. Breakers don't have exposed contact blades the way some switches do.
Clamp to hold breaker takes care of the problem of exposed contacts (and only some models would have them exposed.)

Using 30A breaker is meant to allow full 25A output of inverter, but not pass through 60A from main panel. Something inside the inverter couldn't carry that much.

1x 15A + 3x 20A = 75A total of branch circuits, but inverter can't supply more than 25A continuous. If overloaded, inverter will probably turn off. Or, at something over 30A, breaker will trip.

"Ground" is shown as one wire between two panels, should of course go to all panels an all equipment.

Your panels will look similarly complicated with all wires in place.
What I showed includes an interlocked breaker to bypass the inverter (pre-installed as purchased). Otherwise, if inverter stops working your critical loads have no power, even though grid powers the rest of your house.

 

[tomy2]

The load panel that Ihave is small, like 12"x12". It only has 4 spaces or 8circuits and the 30 amp will be using one space. So I can do one regular 20 amp, a tandem 20 amp and one 15 amp. I will have to wire between lugs. I know that it sounds like a lot of circuits for 25 amps, but I have tested all the main appliances on those circuits and I can't see using more than 20 amps at any given time. If I'm wrong, I can always stick a circuit back in the subpanel. So you don't think that 30 amp breaker needs to be anything special? I probably should have got the 6k model, but it's too late now, it just shipped today. I ordered 10 350 watt panels, but I think I'll start with 6. I don't want to overcharge the inverter. thanks again.

 

[Hedges]

You can get a tandem breaker 20 & 30. That'll give you 30A for inverter backfeed and one of the 20A circuits, in a single space.
For some brands, at least.

SQUARE D QO3020 : MINIATURE CIRCUIT BREAKER 240V 30/20A | Gordon Electric Supply, Inc.

SQUARE D QO3020 : MINIATURE CIRCUIT BREAKER 240V 30/20A

www.gordonelectricsupply.com

(Although tandem breakers may cost you more than you save on panels.

PV panels, if you orient multiple strings differently, that reduces peak power but flattens output over more hours.

 

[DC99]

I'm always surprised by those consumption figures. A regular grid connected detached home here in Finland with a 6+ month heating season, fully electric, sits around 19000 kWh/year, or an average of 52kWh/day.

Same for me. We're in (very) Western Europe and use under 8kwh a day for our house (not rv). Or under 3000 kwh a year. I thought we were low until I saw 3 and 4 kwh a day here!!

My thinking is track what you use, then see can you cut that wayyyyy back without a large impact to how you live much. Any reduction is gonna mean a little change to your house. But if that means more cash in your back pocket and not the utility company....

If I count our EV it pushed the overall usage (house and EV) to 13kwh a day. Which is our 'petrol' costs fully covered too.

That's not living like a hermit. But it's one of each device per house. So one fridge (and it's an under the counter small one). One freezer...We don't have large chest fridge and freezers in most houses typically. We cook on gas. And heat the house on gas 5-6 months of the year (badly insulated 80 yr old house). So we're not 100% electric house.

We use what we need when we need it. So turn stuff off until we need it is our approach. At bedtime we only have the fridge, freezer and house alarm on. Everything else (even down to internet box) is off.

We're lucky either a very temperature climate so summers aren't hot (aircon not installed or needed) and winters aren't brutal. Houses are much smaller too which helps. Looks like aircon uses a huge amount depending on where people live.

And assuming air con is the biggest power hog,
there's gotta be a way to schedule aircon to come on when you leave work so house is cool when you get back. So it's cooled 'just in time'. Someone smarter than me can work that out

So...if you're interested give it a go and turn a heap of stuff off until you need it. Feels good to not make the utility companies richer. All you need to do it take a pic of your meter now. Wait a few days if dontk ow your daily usage alteady. Then turn stuff off and note what you turn off. Treat it like a game to get it as low as you can without living like a caveman. Compare the usage again next week and see how much its dropped. Amd enjoy the savings.

 

[Darren67-72]

15k a day for us, in Michigan usa. Dishwasher, microwave, clothes washer, window air, computer, and all the little stuff.
I just wired in a subpanel and started transferring circuits over one by one, until you reach your max. Each circuit is removed from grid completely separate. Worked great for me.

 

[astroinfidel]

As I've been planning a potential move off-grid I have become very curious to know more about the average annual consumption for those who are already doing it. Obviously minimizing consumption is key to success, but how has that worked out for everyone? Would really love to hear from some folks who wouldn't mind sharing their numbers. I realize it's all relative, but I'm still interested.

I am living full time in a 16x7x7 foot cargo trailer/RV conversion that is in progress. I initially had my system installed by Starlight Solar in Yuma in a 5th wheel, but have since moved it.
I use about 325 amp hours or about 4.6 kw/h a day. About half of that is a big Samsung home 120 volt refrigerator with ice maker. I have a 32 inch computer monitor and Starlink internet which are also significant users of electricity. As well as a microwave, coffee maker, deep fryer and toaster, all of which see regular use.
astroinfidel

 

[tomsilver]

As I've been planning a potential move off-grid I have become very curious to know more about the average annual consumption for those who are already doing it. Obviously minimizing consumption is key to success, but how has that worked out for everyone? Would really love to hear from some folks who wouldn't mind sharing their numbers. I realize it's all relative, but I'm still interested.

Your electric bill should list you monthly KWh consumption. Divide by 30 to get your daily. But keep in mind your peaks will probably be double that on any given week.

 

[tomsilver]

From the wife:

December - charges - $180.95 usage - 1765 KWH

January - charges - $240.72 usage - 2348 KWH

February - charges $284.39 usage - 2774 KWH

March - charges $260.81 usage - 2544 KWH

April - Charge $182.46 usage - 1769 KWH

Good thing we have some of the cheapest power in the nation. Now if I could get her to use the THERMOSTAT instead of the WALL HEATERS that might help... gave up on turning a light switch off years ago.

You are going to be bankrupt using electric energy for heat. Electric prices are going to go through the roof in the next 5 years.