Does the Power company charge you for Solar electric without special meter?

[JohnnyDangerDude]

Does the Power company charge you for Solar electric without special meter(NET metering)

Someone on youtube said the standard meter can detect what your house is using and it assumes its all from the power company and charges you for all the power it sees you using? I'm not sure if that is the case or if it only a situation when the solar panels are pushing electric back into the grid?

In my situation, my house is always using more power than what a Solar panel could ever produce.

Would I be ok with a grid-tie system without a special meter from the power company?

Thanks.

 

[sunshine_eggo]

Does the Power company charge you for Solar electric without special meter(NET metering)

Someone on youtube said the standard meter can detect what your house is using and it assumes its all from the power company and charges you for all the power it sees you using? I'm not sure if that is the case or if it only a situation when the solar panels are pushing electric back into the grid?

Old meters would register any feedback as consumption, so you would get charged if you fed the grid.

In my situation, my house is always using more power than what a Solar panel could ever produce.
Would I be ok with a grid-tie system without a special meter from the power company?

If you are ALWAYS using more power than your ENTIRE array could EVER produce... Probably.

You would want to use hardware that has anti-islanding protection.

I have a very limited GT system I use for a special purpose that has the potential to feed about 300-400W to the grid. I never use less than that, so I've never been caught.

 

[JohnnyDangerDude]

Old meters would register any feedback as consumption, so you would get charged if you fed the grid.



If you are ALWAYS using more power than your ENTIRE array could EVER produce... Probably.

You would want to use hardware that has anti-islanding protection.

I have a very limited GT system I use for a special purpose that has the potential to feed about 300-400W to the grid. I never use less than that, so I've never been caught.

anti-islanding meaning it shuts off the system if the grid goes down so it won't energize the lines on the utility and possible harm the line workers?

 

[740GLE]

anti-islanding meaning it shuts off the system if the grid goes down so it won't energize the lines on the utility and possible harm the line workers?

Correct there is an IEEE and UL standard they have to meet to be accepted by utilities

 

[Sigunas]

anti-islanding meaning it shuts off the system if the grid goes down so it won't energize the lines on the utility and possible harm the line workers?

Yes. Usually, cheap chinese GridTie switches off in a mater of second, when the grid goes down.
If you install grid tie inverter, that has limiting function and power sensor, you can install a lot more solar panels and backfeed only couple of watts.
Older grid metes will register these as used power, but that's very small amount in comparison how much less you will import from the grid.

 

[GXMnow]

Old meters would register any feedback as consumption, so you would get charged if you fed the grid.

This is a bit of a question mark. If it is a very old meter and manually read, it probably counts the NET consumption pretty well.

Most old mechanical power meters with the spinning metal disk do actually spin backwards when power is exported. When home PV solar first started getting popular, it was common to see people bragging about their meter going backwards and getting negative electric "bills". They had to modify the design of those meters to make them only turn forwards. One "fix" was basically a ratchet type mechanism that would just not turn backwards, so you would not get credit for back fed power, as it just could not go that way. They would then add a second power meter that would measure the power from the solar power system, or the grid back fed power. This way they could see the amount being fed back as a separate reading. Making it spin forward with exported power was more difficult for the mechanical meters. It is basically a motor with voltage feeding the field and current feeding the armature. Back fed power is just like reversing the polarity on a DC motor. This is also how low power factor loads turn the meter slower reading the real watts and not the VA multiple of amps x volts.

Some mechanical meters added some basic electronics to count the energy used so that it could be remotely read. But this caused a different problem. (a problem for you, not the electric company) All they did was count the rotations of the disk. Probably a magnet on the disk and a simple reed switch that just outputs a pulse each time the magnet passes the reed switch. That has no way of knowing which way the disk is spinning. And it will cause the electronic count to always go up, no mater if the power is flowing in or out. Now let's say you perfectly size a grid tied PV solar power system to net out ZERO!! During the day with the sun shining, the disk is spinning backwards. The system exports "let's just say 10 KWHs" and the mechanical dials on the meter counted down 10 before the sun goes down. Then the house loads consume that 10 KWHs again all night. The disk turns forward and the dials end up back in the same place, showing no power consumption. BUT..... The pulses counted by the remote read electronics counted 20 KWHs of the magnet passing the reed switch. When I still had a mechanical meter, they would remote read it, but still send out a person for a local read about once or twice a year. If the remote read number and the physical count on the dials are way off, that is a big red flag that something is wrong.

All power meters with a digital display in them can properly count imported and exported power. But if you do not have a Net Energy agreement, they will likely add the import and export numbers together an you will pay for your export. That is your fault for not getting "permission to operate" for a grid tied generating system.

I am all in on sticking it to the electric company, but when you start truly exporting power out to the grid, there are rules that need to be properly followed. If you are not going to get "permission to operate" for energy export, you MUST ensure your system will never export power. Many newer grid tie inverter systems offer a "Zero Export" option with CTs back at the grid connection. And a lot of cheaper "hybrid" inverters can only output power to the output side, and will not push power to the grid side. That type of system can probably be run without permission without ever being noticed by the electric company. And if you truly don't ever export power, I see nothing wrong with that. But if the system does export a little, you might end up paying for power you are giving away. That is the price you pay for not going through the connection process. I may have taken that risk if I had known up front how much my rates were going up as a "Solar Customer" with So Cal Edison. Every KWH I have to buy from them is costing me double what it did before I was a solar customer. It is a crappy deal to get hit with that to be "legal". If you install just a small system to offset only part of your consumption, it is very possible to end up paying the electric utilty more, even if you use less power because of the higher solar customer rates.

 

[chrisski]

In my situation, my house is always using more power than what a Solar panel could ever produce.

Unless you’re talking of a 100 watt panel, I don’t see how that is possible.

I sometimes use 15 kWh an hour but the three large devices that use that can shut down and I still have a 200 watt load for a very few minutes an hour. Anything more than that would register as power going into the grid.

 

[Sigunas]

Į agree with most, what you have said, except this:

All power meters with a digital display in them can properly count imported and exported power.

That's not correct. Digital meters, that can only count power, but not direction, are cheaper, so there is a good chance, that power company installed not directional type. Mine digital counter with remote reading was almost new, when power company needed to change it to directional meter, when I got permission to export to the grid.

 

[JohnnyDangerDude]

Unless you’re talking of a 100 watt panel, I don’t see how that is possible.

I sometimes use 15 kWh an hour but the three large devices that use that can shut down and I still have a 200 watt load for a very few minutes an hour. Anything more than that would register as power going into the grid.

Well, in South Florida, the air conditioner alone runs 24/7 even in the dead of winter unless there is a cold front. It's a 20 ton commercial unit for the house. Even when air conditioner compressors turn off, air handlers still on. We have old thermostat, might open and close the vents but the fans keep running. Water heater is electric , We have computers on 24/7, we have 2 fridges and 2 freezers, 2 washing machines ,1 dryer, pool pumps, outdoor lights that run all night. Fish pumps, pond ponds, etc... Our backup generator is a 55KW and is on the same as an old tractor engine.

Very power hungry house, I don't see how a few solar panels would even put much of a dent in our power usage let along ever create excess power.

 

[AntronX]

It's a 20 ton commercial unit for the house

how many sq.ft. is the house?

 

[chrisski]

Very power hungry house, I don't see how a few solar panels would even put much of a dent in our power usage let along ever create excess power.

I would expect you would need permitting and a interconnect agreement, otherwise the power company would notice the back feed.

Even with a grid zero system, your inverter will push a tiny bit of energy back into the grid when big devices suddenly shut off, like a 20 ton AC.

Whether it’s an Outback Radian, Victron Multiplus, or other meters, these have been caught.

Whether or not a power company picks it up depends on the meter.

A single 100 watt panel is likely less than your idle draw, so that may not be noticed by the POCO, but will have no effect on reducing the bill.

If you redo the AC, you can get mini-splits up to 2 tons that have solar assist built in that have not been noticed by the POCO, except electric bills get too low.

 

[JohnnyDangerDude]

how many sq.ft. is the house?

Around 10,000 square feet The AC has 2 compressors. The second one is sort of a backup or will come on particular hot days. Also, the south Florida area gets very hot pretty much year round.

 

[JohnnyDangerDude]

This is a bit of a question mark. If it is a very old meter and manually read, it probably counts the NET consumption pretty well.

Most old mechanical power meters with the spinning metal disk do actually spin backwards when power is exported. When home PV solar first started getting popular, it was common to see people bragging about their meter going backwards and getting negative electric "bills". They had to modify the design of those meters to make them only turn forwards. One "fix" was basically a ratchet type mechanism that would just not turn backwards, so you would not get credit for back fed power, as it just could not go that way. They would then add a second power meter that would measure the power from the solar power system, or the grid back fed power. This way they could see the amount being fed back as a separate reading. Making it spin forward with exported power was more difficult for the mechanical meters. It is basically a motor with voltage feeding the field and current feeding the armature. Back fed power is just like reversing the polarity on a DC motor. This is also how low power factor loads turn the meter slower reading the real watts and not the VA multiple of amps x volts.

Some mechanical meters added some basic electronics to count the energy used so that it could be remotely read. But this caused a different problem. (a problem for you, not the electric company) All they did was count the rotations of the disk. Probably a magnet on the disk and a simple reed switch that just outputs a pulse each time the magnet passes the reed switch. That has no way of knowing which way the disk is spinning. And it will cause the electronic count to always go up, no mater if the power is flowing in or out. Now let's say you perfectly size a grid tied PV solar power system to net out ZERO!! During the day with the sun shining, the disk is spinning backwards. The system exports "let's just say 10 KWHs" and the mechanical dials on the meter counted down 10 before the sun goes down. Then the house loads consume that 10 KWHs again all night. The disk turns forward and the dials end up back in the same place, showing no power consumption. BUT..... The pulses counted by the remote read electronics counted 20 KWHs of the magnet passing the reed switch. When I still had a mechanical meter, they would remote read it, but still send out a person for a local read about once or twice a year. If the remote read number and the physical count on the dials are way off, that is a big red flag that something is wrong.

All power meters with a digital display in them can properly count imported and exported power. But if you do not have a Net Energy agreement, they will likely add the import and export numbers together an you will pay for your export. That is your fault for not getting "permission to operate" for a grid tied generating system.

I am all in on sticking it to the electric company, but when you start truly exporting power out to the grid, there are rules that need to be properly followed. If you are not going to get "permission to operate" for energy export, you MUST ensure your system will never export power. Many newer grid tie inverter systems offer a "Zero Export" option with CTs back at the grid connection. And a lot of cheaper "hybrid" inverters can only output power to the output side, and will not push power to the grid side. That type of system can probably be run without permission without ever being noticed by the electric company. And if you truly don't ever export power, I see nothing wrong with that. But if the system does export a little, you might end up paying for power you are giving away. That is the price you pay for not going through the connection process. I may have taken that risk if I had known up front how much my rates were going up as a "Solar Customer" with So Cal Edison. Every KWH I have to buy from them is costing me double what it did before I was a solar customer. It is a crappy deal to get hit with that to be "legal". If you install just a small system to offset only part of your consumption, it is very possible to end up paying the electric utilty more, even if you use less power because of the higher solar customer rates.

Checked on my meter. It's Digital and has wireless communication with FPL(Florida power and light). It made by a company called Silver Spring Networks. Type Focus AXR.

 

[AntronX]

Around 10,000 square feet The AC has 2 compressors.

Cool. Why not go with basic grid tie system installed with a permit?

 

[JohnnyDangerDude]

Cool. Why not go with basic grid tie system installed with a permit?

I will never produce more solar than I use. Why do a permit if you don't need to? I probably use a minimum 12,000 watts at any given time and I'm looking at panels that will produce under 1,000 watts. Question is if back feeding that power into a random outdoor plug going to find its way for power uses in my house. Do the circuits have to be configured in a certain way to allow this or does it naturally happen?

 

[JohnnyDangerDude]

I would expect you would need permitting and a interconnect agreement, otherwise the power company would notice the back feed.

Even with a grid zero system, your inverter will push a tiny bit of energy back into the grid when big devices suddenly shut off, like a 20 ton AC.

Whether it’s an Outback Radian, Victron Multiplus, or other meters, these have been caught.

Whether or not a power company picks it up depends on the meter.

A single 100 watt panel is likely less than your idle draw, so that may not be noticed by the POCO, but will have no effect on reducing the bill.

If you redo the AC, you can get mini-splits up to 2 tons that have solar assist built in that have not been noticed by the POCO, except electric bills get too low.

If my minimum power usage is 12,000 watts and I'm producing a max of 600 watts from solar being back feed into the system.

This would not give me around 600 watts of savings?

1. Can backfeed happen even if you are always using power from the power company at any given time?
2. Are you saying the power company can charge you for power you generate from solar panels even if its not backfeed into the system?

Thanks.

 

[AntronX]

Sure you can tap into some 240V circuit like a water heater with a bunch of Enphase micro inverters. I've done it with 2 of them. But I am not sure why even bother with 1kW solar that will save you $300/year at most while you are using $10k of electricity for cooling during summer alone. Makes sense to do it as a hobby experiment.

 

[JohnnyDangerDude]

Sure you can tap into some 240V circuit like a water heater with a bunch of Enphase micro inverters. I've done it with 2 of them. But I am not sure why even bother with 1kW solar that will save you $300/year at most while you are using $10k of electricity for cooling during summer alone. Makes sense to do it as a hobby experiment.

People don't really do solar panels in my neighborhood. I have an area that has sort of a flat spot on part of the room where I can sort of hide them from view. If it turns out ok, I might be able to add some more down the road.

So you have to tap into a large power draw circuit, back feeding it into a random plug won't allow the power to find where its needed in the house automatically?

I also have other plans to save more using types of geothermal/liquid cooling for my AC that may save more than solar power but that is a topic for another day.

I am right now concern on if the power is able to find its way to where its needed without advance electrical knowledge and work. I was hoping just to plug it into a plug and have it back feed to the entire house and it can just sort of use what it needs but you are saying you need to connect it right the a large load circuit directly?

 

[jzampieron]

I just had my meter changed last week. The old one was digital and the new one is digital as well.

The difference is the new meter has a "01" and "02" that alternate on the display... best I can tell "01" is power coming in from the PoCo and "02" is power I'm pushing back out.

The process to get interconnection approved w/ Eversource took a while, but really wasn't difficult for a DIY solar type. If you can get a DIY solar system going, you can get the PoCo paperwork done.

I recommend doing it the right way or at least setting up your electronics for "Zero Sell".

If you are talking about backfeeding via a plug I sure hope you are using something like a system from PluggedSolar and not a death-cable.

 

[AntronX]

I am right now concern on if the power is able to find its way to where its needed without advance electrical knowledge and work.

If you don't know electrical then don't mess with 240v. Start with small 12V stuff it's much safer. I still don't understand why you want to do this in a 10Kft² house? I guess you are a tenant or it belongs to your parents?

 

[chrisski]

IMO adding solar for your situation will save no money and will end up costing more.

To me your power usage is a commercial build, not residential.

A lot of my neighbors got a favorable NEM 1.0 agreement, but those are gone here by six years and most of their advice about oodles of money saved is bad. Many of them forget to tell me about the $1500 a year increasing lease fee for a $2500 electric bill. They also forget to say they spend a few hundred dollars a month in the hot months for AC and are worst off than they know or admit.

My NEM 3.0 similar agreement is not financially favorable.

1. Can backfeed happen even if you are always using power from the power company at any given time?

I don’t know but, if they can’t tell if you have a load, but What happens in the one cool day of the year when the AC shuts off?

Each system is different on how much this spike will be. A single unit running a 10k SQ FT house for an AC (15 kw?) going shutting off during a 2 kw load may. Not a thing you’ll honestly know until you buy it.

Also, when a power outage happens you have 600 watts going to the grid without an auto shutoff.

2. Are you saying the power company can charge you for power you generate from solar panels even if its not backfeed into the system

Yes. Solar is not new and they know how to get there money.

I have a fixed rate per kW of panels regardless if sold back or not.

Depends on your agreement. In AZ in part this is determined by the Corporate commission. Each county / state / and utility is different.

Supposedly (because I read in news articles but can’t find the source) certain areas like Tucson are only allowed 15% of power to come from solar, so if too many have built already, the permit is not approved.

 

[AntronX]

Also, when a power outage happens you have 600 watts going to the grid without an auto shutoff.

If he uses quality grid inverter it will not. Lets stop spreading this old lie.

 

[chrisski]

If he uses quality grid inverter it will not. Lets stop spreading this old lie.

What 600 watt inverter would you recommend? What’s the smallest inverter for grid zero? Multiplus?

 

[AntronX]

What 600 watt inverter would you recommend?

3x Enphase IQ7 or IQ7+ can be had for $50ea. on fleabay.

 

[jzampieron]

What 600 watt inverter would you recommend? What’s the smallest inverter for grid zero? Multiplus?

I mean... there's this... which I kind of recommend for DIY solar people who aren't really DIY solar people.

Plug and Play Solar Panel Power with 750 DC-Watt Inverter; Simply Plug into Wall; Expand upto 600Watts

Product Features Estimated Electricity Generation: 600kwh/yr. by using 300Watt from Solar Panels (ave. saving of 7.5% of electric bills for an average home) & 1200kwh/yr. by using 600Watt (average 15% of electric bills for an average home). Do It Yourself: No wiring is needed & no battery is...

pluggedsolar.com