"on gird" and "off gid" system in on

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got_nailed

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-This is not ground V\S bonding but I think it runs up close to it.
-Yes I am NOT an electrician but there is one that did the work and any changes needed.


I have had an ?off grid? house for about 15 years. It is PV and wind powered (with batters and so on). I?m running 2 linkable inverters that each make 35 amps at 240 volts. Both inverters have there own 30 amps CB that is screwed in to the panel board this is on a 200 amp panel. I have a 200 amp CB that is running 4/0 SER in to my house about 50 feet away in a 4? PVC pipe to a 200 amp panel where all of my house hold circuits are.

Last week I had an ?on grid? system put in. It is a parallel 200 amp service (400 amp meters). It was also put in to the shed. The power company wanted to use a 400 amp service because down the road I will want to sell of power. The electrician put in a 200 amp panel in the shed and a 200 amp CB is running 4/0 SER in to my house about 50 feet away in a 4? PVC pipe to a 200 amp panel. My heat, AC, range, and water heater are in this panel.

I wanted to be able to switch my well between the ?off grid? and ?on grid? systems. So he put in a 100 amp generator panel. The panel he put in only switches the 2 hot wirers. Ever since he put in the new system I have been having problem with voltages on both systems. I did have him come back out and remove the wiring from the ?off grid? system to the generator panel and the voltages have been fine since.

The grounding for the ?off grid? system is. A ground rod at both of the wind turbines. A ground ring in the shed. A ground rod outside the shed for the PV panels. They are all #2 copper that run into the 200 amp panel in the shed. There is also a ground jumper between the -24 volt batter system and the panel. The panel is also bonded to the water pipe. Around my house there is a ground ring that goes in to the 200 amp sub panel it is also bonded to the water pipe in side the house. This was done about 15 years ago and has not changed.

When the electrician put in the new panel in the shed he put in a ground rod because of the power company. And also ran#4 copper between the 2 panels in the shed. In the house he ran a #4 copper between the 2 sub panels.

-If I get a generator transfer switch that will switch the neutrals as well will, keep my voltage problem from happening?
-I do not understand why the voltage problems happened.
-Why would an electrician no go by the plans that the inspector and utility engineers signed for my house? If he was trying to be cheep he charged me $6000 and the PVC was already there. I know the materials only cost $1359 at HD if I would have gotten them.
 
Re: "on gird" and "off gid" system in on

You're describing a complicated system. It would be impossible for us to use your description to provide you with any kind of accurate answer to your problem.

But, looking at the first bit:
I have had an ?off grid? house for about 15 years ... I?m running 2 linkable inverters that each make 35 amps at 240 volts.
Click to expand...
I'm assuming you didn't upgrade your inverters?

If you are using utility power, and trying to get the most from your old PV system, you really need to invest in a grid-intertie inverter, in my opinion. I'm assuming that's why two 200 amp services were installed. One meter is for the power company to sell you power, and the other is for you to sell yours back.

How are you planning on using both?

-Why would an electrician no go by the plans that the inspector and utility engineers signed for my house?
Click to expand...
How were the plans deviated from?
 
Re: "on gird" and "off gid" system in on

Does your utility not offer net (meter spins both ways - foward when you're consuming more than you;re producing, backwards when your producing more than you're consuming) metering? Why 2 seperate meters?

I think George is correct, without an intertie inverter you're power system is out-of-phase with the utility's. A common neutral won't solve that.
 
Re: "on gird" and "off gid" system in on

Originally posted by LawnGuyLandSparky:
Does your utility not offer net (meter spins both ways - foward when you're consuming more than you;re producing, backwards when your producing more than you're consuming) metering? Why 2 seperate meters?
Click to expand...
Do they make such a thing?

I believe under federal law, power companies are required to allow customers to sell power back to the grid. Under that rule, the POCO is only required to pay out what they pay others for the power.

So while the power company is selling power for, say, 7?, they only have to purchase it for 4?. So two meters is the only method I've heard of to keep track of the two transactions.

But I am far from an expert on this topic. :)
 
Re: "on gird" and "off gid" system in on

George,
it depends on your utility and/or your PUC rules. Many allow "small" producers to use net metering. The line that sperates you from small to a bonified distributed generation plant is some kW rating as deterimned by your utility. This keeps me from installing a 500kW nat gas turbine at my house and seiling power at $0.13/kW. You'd have to check your utilities "book" for the max kW you are allowed. Usually, it is fairly large for a residence, but that is my experience only in CA.

mike
 
Re: "on gird" and "off gid" system in on

George
-No I did not upgrade my inverters. Both of my inverters are grid-inverters but not set up like that right now. I do have the one setup to make power all the time. When it hits 15 amps on ether poll it will turn the other one on. I had it set up this way because until last week I was running my entire house on them.

-The meter is a 400 amp can (only one meter can). The can is set up to feed 2 200 amp services.

-I had got my local inspector involved and the power company because I did not want a chance for back feeding into the grid at this point. Down the road I am planning on selling power back to the utility.


Lawn
-The meters they use are for net meters. At this time I am not using this plan. But the meters are the remote reading meters.

George
-Where I live (VA) you pay for the energy that you use. If you make more then what you use then it?s at the lower cost. Other wise they buy back the power at the same rate as you?re using it.

At this time I DO NOT want to sell any power to the utility. The power was run out to my neck of the woods about 1 month ago and there are many outages because there still working on it a lot.

What I am doing is running most of my house off my ?off gird? system and using the power company for just a few higher amp things; heat, AC, range, water heater, and well. I do want to be able to put the well on my ?off grid? power when needed. This is why I wanted the transfer switch. During the winter I do think the power will be off for long period of times because the lines are through the woods. I would still like to have power to my house when this happens.

I do not have the book in front of me about how much power I can sell back.
 
Re: "on gird" and "off gid" system in on

Why wait to sell them back power?

Anyway, going back to your beginning questions:

-I do not understand why the voltage problems happened.
Click to expand...
Neither do I. But really, it's a hands-on issue with such an involved system. A verbal description is no substitute for real troubleshooting, which your electrician should be qualified to do. (Or so we hope, right? :)

I've studied the NEC's PV article, and it is very difficult to say the least. If he is indeed proficient at both PV systems and regular AC work, he is worth his weight in gold, and deserves some respect. :D

So, have faith, and if something isn't right, get it fixed. ;)
 
Re: "on gird" and "off gid" system in on

Net metering is Law here in NY.

http://www.lipower.org/cei/solar.metering.html


METER511.gif


What is Net Metering and How Does It Work?

Through New York State?s Net Metering Law and LIPA?s Tariff for Electric Service, residential customers with PV systems 10 kW or less are entitled to net metering. At times, a net metered customer?s PV system may generate more electric energy than their consumption. When this occurs, the electric meter will spin in reverse. The excess electricity is returned to the LIPA system. At the end of each month, the net metered customer is billed only for the net consumption, that is, the amount of electricity consumed, less the amount of electricity produced. This is called ?net metering.? Your meter is currently spinning in the "Consumption" mode. To spin your meter backwards due to PV, we need to reverse the dials direction to simulate a reversing meter.

Why is net metering important?

There are three reasons net metering is important. First, as increasing numbers of primarily residential customers install renewable energy systems in their homes, there needs to be a simple, standardized protocol for connecting their systems into the electricity grid that ensures safety and power quality. Second, many residential customers are not at home using electricity during the day when their systems are producing power, and net metering allows them to receive full value for the electricity they produce without installing expensive battery storage systems. Third, net metering provides a simple, inexpensive, and easily-administered mechanism for encouraging the use of renewable energy systems, which provide important local, national, and global benefits.
What are the benefits and costs of net metering?
Consumers benefit by getting greater value for some of the electricity they generate, by being able to interconnect with the utility using their existing utility meter, and by being able to interconnect using widely-accepted technical standards.

The only cost associated with net metering is indirect: the customer is buying less electricity from the utility, which means the utility is collecting less revenue from the customer. That's because any excess electricity that would have been sold to the utility at the wholesale or 'avoided cost' price is instead being used to offset electricity the customer would have purchased at the retail price. In most cases, the revenue loss is comparable to having the customer reducing electricity use by investing in energy efficiency measures, such as compact fluorescent lights and efficient appliances.

Can I use my existing meter to take advantage of net metering?

The standard kilowatt-hour meter used for residential customers will be replaced with a "net meter", which accurately registers the flow of electricity in either direction. This means the 'netting' process associated with net metering happens automatically-the meter spins forward (in the normal direction) when the consumer needs more electricity than is being produced, and spins backward when the consumer is producing more electricity than is needed in the house or building.

How can I be sure that these small-scale PV systems are safe?

During the last decade there has been tremendous technological progress in the design of the equipment that integrates small-scale generators with the utility grid. Called 'inverters' because they were originally designed only to 'invert' the DC electricity produced by solar arrays to the AC electricity used in our homes and businesses, these devices have evolved into extremely sophisticated power management systems. Inverters now include all the necessary protective relays and circuit breakers needed to synchronize safely and reliably with the utility grid.

What LIPA and State Incentives are available to help minimize the cost of purchasing a PV System?

LIPA?s Solar Pioneer Program, combined with tax incentives currently available from New York State, makes this a great time to consider solar power for your home. LIPA offers direct incentives that significantly reduce the cost of utility interconnected photovoltaic (PV) systems sized up to 10 kilowatts (KW). Residential customers may also pursue a New York State tax credit of up to $3,750. In addition, homeowners may take advantage of New York State?s 15-year property tax exemption for Solar Energy Systems (check with your municipality to see if you?re eligible).

As a Net Metered Customer, How Will LIPA Bill Me?

Net metered customers are billed on a monthly basis. BALANCED BILLING customers who become net metered customers will be removed from BALANCED BILLING and billed on a monthly basis based upon their energy consumption.

All net sales transactions are based on a ?contract year,? which begins with the date the net meter is installed by LIPA. During the contract year, LIPA?s retail energy rates are applied to the net energy or kilowatt hours that are consumed from LIPA each month. LIPA?s retail rates range from 11.79 cents per kWh to 13.677 cents per kWh and includes the Fuel Purchased Power Cost Adjustment (FPPCA) rate. These rates will vary based upon the season and the amount of energy consumed from LIPA.

What If My PV System Generates More Energy Than What I Consume From LIPA?

During the month, if a net metered customer generates more energy from their PV system than he/she consumes from LIPA, the customer is billed for the daily service charge only (meter charge) and the excess generation in kilowatt hours (credits) is placed in an ?energy bank?. Energy from the bank can be withdrawn in subsequent months to reduce the net metered customer?s billed consumption during the contract year.

Annually, on the net metered customer?s anniversary date, LIPA will reconcile the energy bank. The total monetary value of the energy bank is calculated to combine the monetary values for each month during the contract year at the rates specified in LIPA?s SC-11 buyback or wholesale avoided cost rate, which is approximately 0.375 cents. This rate will vary upon each season. This total amount of money will be credited to the net metered customer and the customer?s energy bank (in kilowatt hours and dollars) reset to zero and the end of the contract year.

What If My PV System Produced More Energy Than What I Consumed From LIPA At The End Of The Contract Year?

At the end of the contract year, in the event that the cumulative dollar value is positive (your PV system produced more energy than you consumed from LIPA) end of year reconciliation dollars will be applied as a credit to your LIPA customer account and the energy bank reset to zero.

What If I Consume More From LIPA Than What My PV System Produces At The End Of The Contract Year?

In the event that the cumulative dollar value is negative at the end of the contract year, (you consumed more from LIPA than your PV system produced) you will be billed that amount by LIPA at the retail rate and the energy bank reset to zero.

Net Metering for Time-of-Use Customers

As a LIPA Time-of-Use customer, in order to net meter, LIPA requires that you have a second, non-time-differentiated meter wired to your service. Both meters will only be able to record electrical consumption in one direction. The LIPA revenue Time of Use meter will record only the energy provided by LIPA and will be identified as the ?sell meter.? The ?sell? meter will be programmed to record LIPA energy you consume utilizing the appropriate Time-of-Use rate structure. The second meter will be identified as the ?buy meter?. This meter records the amount of kWh energy that you have generated and are selling back to LIPA.

According to LIPA?s billing tariff for residential small solar electric generators (PV systems) who are served under a residential Time of Use Service Classification, LIPA will combine the purchases and sales recorded on the two meters by first offsetting purchases from LIPA during the peak period by the amount sold to LIPA in a given billing period. Any additional energy supplied from the PV system will then be used to offset the off peak period within the same billing period. After satisfying the current billing period, any remaining kWh energy will be carried over to the next billing period and will be used to offset LIPA energy rates. All net sales transactions are based on a ?contract year,? which begins with the date the second ?buy? meter is installed by LIPA. At the end of the contract year, LIPA will adjust any remaining energy credits at LIPA?s SC-11 Buyback or wholesale avoided cost rate, which is approximately 0.375 cents. This rate will vary upon each season. The total amount of money will be credited to the Time of Use net metered customer account and the customer?s account reset to zero at the end of the contract year.

If you install a second meter, you will be responsible for the installation costs of the second meter, which include the cost of the meter pan, meter mounting devices and all necessary equipment and wiring. You can avoid the installation and cost of a second meter by choosing to be on a non-Time-of-Use rate (standard electric rate). You must notify LIPA and request the change in rate classification, in writing, at least thirty (30) days before your Time of Use anniversary date. The transfer will take place on the Time of Use anniversary date.

Please note: LIPA will verify the metering and billing of a LIPA net metered account, but recommends that net metered customers contact their PV contractor if their PV system is not performing as expected.
 
Re: "on gird" and "off gid" system in on

I do not want to sell back power at this time because of the reliability of the power. At least now most of my stuff will have power, just not the higher amperage stuff.

With the info that I have that the question about the voltage problem will not be know unless I know more.

I got intact with my inspector and utility engineers are, because where I live there are, only 4 people that use PV systems. Calling and trying to finding someone that knows what they are doing when installing stuff that is not normally installed. I wanted my system to be safe. I don?t need to kill a line man from sending out some power and the power company not knowing I?m sending any out.

I know that is not far for me to look at the prices of what something cost and compare it to what I paid someone to do it for. But after he did not do what I wanted (I know that it was the safe and right way to do it), it dose piss me off.

I do know about the net metering where I live. My power company gave me a book on it. Where I live they use a different meter then what that post talks about.

I have not changed any thing with my power since the election came out to my house to look at the job. I did hold a meter up the main lugs of the panels but that was it.

PS? some times I wonder if people read the post before the respond. I can tell all this will be is a bunch of posting where the same thing is going to be asked over and over.

Thank you and I can tell that with out me knowing more (need to be able to test and chart what is happening) you can not help me.
Thank you for your time?.
bob
 
Re: "on gird" and "off gid" system in on

The only item I can suggest is to look at your neutral bonding. I thought most inverters didn't like to have their ground and neutral separated, so you're stuck using them at the service equipment and no place else. If you now have sub panels and connected an inverter to one, that may be part of your problem. You didn't post a wiring diagram, so we don't know what you've done. But I don't know enough to help you even if you did that...
 
Re: "on gird" and "off gid" system in on

Is there a program that I can though a wire diagram together with? Paint and draw suck for things like this. Yes the inverters are on a panel with the neutral ground bonded. It?s feeding a sub panel that the neutral ground is not bonded where most of my load is.

I?m thinking that there was a problem with the neutral wire running between the 2 sub panels (running through the transfer switch). When it was there my line voltage dropped to about 98 volts per poll and 199 poll to poll. When it was removed it went back up to 109 poll to ground and 218 poll to poll.

By my under standing it is dangerous to bond a sub panel. No I do not know the entire reason behind this. But I do not know if it will help in this situation. When I get home from work I will try to draw up a wire diagram and look at the neutrals and grounds in all of my panels.

Thank you Suemarkp

[ February 04, 2006, 04:31 AM: Message edited by: got_nailed ]
 
Re: "on gird" and "off gid" system in on

You can use drawing programs (canvas, visio), and even the drawing capabilities of MS Word and Powerpoint should be fine for this. Save them as JPG's. You can also draw it on paper and scan it, and post that jpeg.
 
Re: "on gird" and "off gid" system in on

Ok I posted a link to a drawing of what I have set up. But the green box at the bottom is my house the top ? is the shed.

Pic. it's large so you might need to zoom out.

As for net metering, I don?t want to do this at the time because the power goes off a lot. i want constant power. But I can feed most of my house with it. At some point I want to be able to go back ?off grid? but will need to put up the other 3 towers and wind turbines and the second battery bank. My parents moved in with me because of there age, they need better heat and AC so I had to do some upgrading.

george let me re phrase something for you. ?-Why would an electrician no go by the plans that the inspector and utility engineers signed for my house?? Let say it was a spec sheet for my house (job) but it was not followed. As of right now I?ve paid $3,000 and no more till the job is done to the job spec sheet. According to the contract he has 30 day from the job start date. According to my POCO they wanted me to meat with the utility EE to see how everything was set up. Because of a code issue I had with what he wanted done I had to meat with the inspector and the utility EE to get on common ground. I did want my system to be safe for me and the line workers.
 
Re: "on gird" and "off gid" system in on

Which panels have bonded neutrals and which have unbonded neutrals (include the transfer panel in this answer)? What type of cable goes from the 200A shed panel on the right to the 200A house subpanel on the right -- is it 3 or 4 wires?

This does not look like a 400A service. You only have one 200A panel connected to the meter. Is that right or are you missing another 4/0 SE somewhere?
 
Re: "on gird" and "off gid" system in on

Those #4 bonds look fishy to me.

I think how and where those are connected are important to your problem.

I think we're beginning to walk a tenuous line here. :(
 
Re: "on gird" and "off gid" system in on

Everything in the shed is bonded. Everything in the house is unbounded. The meter can is set up for 2 200 amp panels. Yes there is only one it right now. From the shed to the house is 4/0 SER (4 wire) on both runs.

The transfer panel is 4 wire, but the nutrals are not switched. I think that is where a good pare of my probles are. the bond wire in the house should not be there fomr what i have had. this gives a ring for the power to flow witch i think is bad (but i don't know why.
 
Re: "on gird" and "off gid" system in on

You're exceeding my level of knowledge for the equipment you have. I would double check the transfer switch to make sure the neutral doesn't have a bonding screw installed and that there are in fact separate busses for the neutral and ground in that switch box.

I don't think you can get rid of any of your bonding wires. I'd consider some of these to be ground electrode conductors and your system has been complicated by the fact that your ground electrodes aren't in the utility service panels. So you have to run a 250.66 sized jumper or ?GEC tap? to the next panel which has the ground electrodes.

I am also unsure of whether power derived from inverters can be treated as a service. It is wired as such, and all your services need to have a common grounding system, so you can't get rid of the bonding wires in the shed either.

Having the grounds go in a circle isn't a problem if they are really just equipment grounds. But if they are carrying current (which they will on the shed side or any service equipment) then you could have some strange things happening.
 
Re: "on gird" and "off gid" system in on

I just looked into the transfer switch and it dose have sprite busses. The neutral buss is insolated with black plastic.

I?m thinking of just letting it all ride out since I?m not having any problems at the moment. I have paid the electrician $3000 and POCO $2000. I do owe the electrician more money but he has not done the job to specs and he had 30 days from the start of the job, I?m thinking of just letting his time run out and let it go to court. After his 30 days are up get someone in to toss the transfer switch and put the well back on my ?off gird? panel.

I do plan on putting up 4 more wind mills and putting second battery bank. This would let me run the whole house ?off grid?. I think I went bad with trying to not update my system to handle the entire load. Just wanted the quicker way out.
 
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