Approval free alternate energy tie ins ??
Approval free alternate energy tie ins ??
(OP)
Why can't you go to your home improvement store and buy an alt energy system and use it to offset your homes power usage.
The utilities don't like it that's why.
The main reason cited is line worker safety from back feeding the grid. If that is the only drawback I have the solution.
Why cannot the utility place a Power line carrier signal on their lines that travel through the grid and find their way to the utility intertie inverter that refuses to supply power without seeing it.
Presto. If a grid source breaks the alt sources go down automatically as a result of loss of the carrier signal.
This should not be a serious technological problem and it would allow off the shelf purchases of Alt energy systems to be purchased and tied into the grid for lowering utility bills.
When the consumer can see it and touch it and take it home and use it there would be much higher uptake of alt energy systems and the savings would mount silently.
Any reason this wouldn't work.
The utilities don't like it that's why.
The main reason cited is line worker safety from back feeding the grid. If that is the only drawback I have the solution.
Why cannot the utility place a Power line carrier signal on their lines that travel through the grid and find their way to the utility intertie inverter that refuses to supply power without seeing it.
Presto. If a grid source breaks the alt sources go down automatically as a result of loss of the carrier signal.
This should not be a serious technological problem and it would allow off the shelf purchases of Alt energy systems to be purchased and tied into the grid for lowering utility bills.
When the consumer can see it and touch it and take it home and use it there would be much higher uptake of alt energy systems and the savings would mount silently.
Any reason this wouldn't work.






RE: Approval free alternate energy tie ins ??
RE: Approval free alternate energy tie ins ??
Yes, because utilities completely despise user backfeeding. They only allow it because it is mandated by govt and for PR. They certainly won't do anything to help anyone do this, such as your solution.
On your solution, it would be very expensive as the carrier frequency you suggest won't reliably pass thru transformers.
Also, it is completely unnecessary for the task. It is easy to prevent the scenario of back feeding using other methods. One company had an outstanding solution that people started flocking to. It was a completely safe way for you to hook a solar panel to this wall-wart and plug the wall wart into any outlet. It would only close circuit to the power if the power was present. If the power went away it would instantly drop out. This essentially allowed anyone to start at any size with reducing their power bills. They didn't have to drop $30 or $40K. That company was bought by Xantrex and suddenly that 'solution' disappeared over night. It was very sad.
Keith Cress
kcress - http://www.flaminsystems.com
RE: Approval free alternate energy tie ins ??
I never did anything at the residential level, but there sure ought to be a simple device like you described.
On the bigger cogeneration sites, the utility (usually TVA in my area) always required us to design-in protection plus a remote kill under their control. Since most of the projects involved recovering waste heat, I was able to design around small turbines and induction machines -- inherently safe since they need utility power for a field.
I could make a market for those wall-wart things you described, I bet!
Good on ya,
Goober Dave
RE: Approval free alternate energy tie ins ??
You are right they hate backfeeding. But they have no right to a monopoly.
As far as the carrier it might be selectable to pass transformers and not be absorbed by loads.
My point is that a legally mandated standard is needed in order to eliminate the bureaucratic wall of red tape erected to prevent uptake.
stevenal
I assure you my concern would be a system as full proof as possible, and this seems to be not beyond the realm of possibility for the engineering community.
The beauty is that a standard adopted into federal law would preclude the need to submit to utility badgering and inverter manufacturers would have a standard to manufacture to. The elimination of the communication and confusion would be a boon to alt energy.
If a carrier can't do it, how else could it be done with 100% certainty.
RF receivers in the inverters, receiving utility narrowband signals ?????
The key to the compromise is giving the utilities a remote kill switch. They having the control would have a hard time making the case that it is dangerous.
RE: Approval free alternate energy tie ins ??
RE: Approval free alternate energy tie ins ??
Anti-islanding is accomplished by inverters that attempt to run fast. If not held back by strong grid, they will disconnect when they sense the resulting over frequency condition. Like any electrical device, they are built and tested to a listing agency standard such as UL.
I think you are trying to fix a problem that does not exist.
jghrist,
Good argument for implementing a basic service charge. Same argument applies to vacation homes. Little energy used, but they want it there when they want it.
RE: Approval free alternate energy tie ins ??
Off the top of may head, some applicable standards for "grid tie" PV installations are IEEE 929, UL 1741 and NEC 590. It's a fairly popular practice in the west. See www.livesolar.net There's ten of them currently listed.
Don't forget there's still a permitting and inspection process to go through. All the ones I've seen have 600V visible-blade heavy-duty lockable disconnect switches accessible to utility workers 24/7 for isolating either the AC or DC side, {local-utility preference I guess} regardless of the inverter(s) rating.
One other point—lineworkers are blatantly lazy/stupid for not using personal-protective grounding in their clearance process.
RE: Approval free alternate energy tie ins ??
>>That company was bought by Xantrex and suddenly that 'solution' disappeared over night.
Which unit was that, Keith ?
boB
RE: Approval free alternate energy tie ins ??
How long do you think your local grocer would permit it if you began to come in and put your merchandise on his shelf? In effect anyone who puts power on the grid other than themselves is competing with the profits they make on their own generation although this is changing with deregulation and diversification of generation companies from T&D companies.
The safety aspect however is still the most important for anyone connected to or working on the grid.
rmw
RE: Approval free alternate energy tie ins ??
The state of Missouri recently passed a law requiring $100,000 of liability insurance for small grid-tie systems. According to a article in today's Kansas City Star, the problem with that is that there are no insurance companies that can provide this coverage.
RE: Approval free alternate energy tie ins ??
Yes, I'm sure it was.
It was a micro grid-tie. A fellow EE and I were both considering purchasing them. He was a little more motivated than I. About a week later he decided to buy his. He goes to the Trace site and discovers it's gone and the company has been changed to Xantrex. Everything is the same except that one single product is gone. He promptly called them and was told, "We are not producing that product any longer". They were very curt about it and would provide absolutely no comment about it. They seemed a bit angry even.
As far as we could tell it wasn't just phased out it was 'stamped out' like a burning ember.
We started thinking Trace was purchased by some shady entity for the sole purpose of buying the rights of that device and crushing it. Thoughts of dark conspiracies, trench coats, hit men, lobbyists, and lawyers came to mind.
I could imagine a big power company buying out Trace from petty cash to nip a new, bad-for-them, technology.
But who knows. It could have been something like a nasty letter from a power company.
I would really like one as I always creep into the third tier where my power starts costing 26 cents/kWhr. Being able to use a few solar panels to just back out that 3rd tier stuff would be great and a good return on my solar dollars.
Oh well.
Keith Cress
kcress - http://www.flaminsystems.com
RE: Approval free alternate energy tie ins ??
>>e started thinking Trace was purchased by some shady entity for the sole purpose of buying the rights of that device and crushing it. Thoughts of dark conspiracies, trench coats, hit men, lobbyists, and lawyers came to mind.
Keith,
Your are very close here... That micro grid tie unit was the OK4U 125 Watt or so unit, made in Europe (still is I believe) The problem was that it wasn't UL1741 listed so they had to stop selling them in the USA. This one wasn't Xantrex' fault, but still, you weren't too far off in many ways !
I worked at Trace and through that transition for another year. Xantrex has now been bought by Schneider Electric.
The timing was just a coincidence in the case of that particular inverter.
boB
RE: Approval free alternate energy tie ins ??
I was hoping someone would know what the actual facts were!
Thanks for clearing that up boB.
Keith Cress
kcress - http://www.flaminsystems.com
RE: Approval free alternate energy tie ins ??
26cents?? Holy cow!
RE: Approval free alternate energy tie ins ??
So in this scenario, what would be the purpose of even having an alternate source if BOTH go down if the grid goes down? Makes no sense to me.
Be that as it may, line carrier signals can be made to work, in fact we will soon be seeing that technology in use with a lot of the major utilities for TOU billing programs. But as stated earlier, would YOU as a lineman want to be stripping a HV cable at the moment when the microprocessor in someone's alt energy system decides to reboot and takes a second or so to figure out that the carrier signal is not there? I would not. I want an air gap, preferably one that I can see and install my lock onto.
Besides, what's the problem with installing an isolation switch anyway? I would think that if you are so financially strapped so as to not want to go through the necessary approval steps to connect to a grid safely, then you probably will not be able to afford proper maintenance of your alt energy system eithersystem, thereby disqualifying you to be connected to the grid in the first place.
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RE: Approval free alternate energy tie ins ??
RE: Approval free alternate energy tie ins ??
So the arrangment is, if you want to be paid for alternate energy production, you let us meter it, inspect it, and be able to disconnect it when needed.
In general grid tie inverters work, as do induction motors, but we have to know they don't produce to much noise that you nebors will complain about.
RE: Approval free alternate energy tie ins ??
You have touched on the exact issue. The utilities do not want grid tie sources for some economic reasons.
However if we adopt this thinking as legitimate then there is not alternative energy industry at all, as it is counter to utility interest. These concepts would condemn even alt sources that augment utility purchased power.
I cannot believe that at a time when there is much whining about all the new generation capacity we are going to need soon that allowing alt sources is a bad idea.
cranky108
If grid tie systems were limited in power level i find it hard to imagine any issue that could not be handled by Standards for design and installation.
My central idea is that a standard design and standard installation should allow installations without inspection or even approval by the utility.
To require anything else is to doom alternative energy for the individual and throw out the possibility of significant power augmentation by homeowner installed systems.
RE: Approval free alternate energy tie ins ??
The biggest setback for solar is the 20 year payback, for equipment that is expected to last only 15 years.
Truthfully, it's more cost effective to heat water with solar, then generate electricty.
If you want to talk about wind, no we don't want more than is mandated, because it requires us to rase our costs to our other customers.
If you want to connect to our grid without telling us, the meter won't turn backwords. You won't be paid for the electricty, and a electrical inspector from the area will be sent to your home (NEC requirments adopted by the state).
RE: Approval free alternate energy tie ins ??
RE: Approval free alternate energy tie ins ??
RE: Approval free alternate energy tie ins ??
Who provides the other $0.36?
RE: Approval free alternate energy tie ins ??
In my area PG&E runs the show. They have pretty much disposed of all their generation. They still have some odd stuff. (nukes and geothermal)
I would think PV from homes should allow them to reduce their capital outlays for new power plants.
They still charge "transportation" charges. If you pumped 2x the power you use monthly onto the grid they'd still charge you for a connection (transportation).
Keith Cress
kcress - http://www.flaminsystems.com
RE: Approval free alternate energy tie ins ??
Remember the Xantrex recall because one model of their inverter did not island correctly? It was a pretty stand-up recall but it still points to the potential hazards.
But, back when I was reading about this stuff a lot more, the only cases I read of the utility PV switch being opened was during the IBEW strike in some area of California where the line workers were going around and locking off PV systems as part of their strike action.
I've always believed utility workers worked on the lines using live line practices unless they disconnected and grounded the lines. The lines are assumed live until grounded so they would not bother to open a PV disconnect but rather just test for dead at the work site and then install grounds.
RE: Approval free alternate energy tie ins ??
RE: Approval free alternate energy tie ins ??
99.999999% of the islands would instantly take out any paltry back-feed source. Sources like the OK4U would likely have issues with just energizing an unloaded 5 house pole transformer.
A small 2kW solar unit is also going to choke on the same scenario, trying to run 4 or 5 typical homes.
And of course, as pointed out, why would someone work on an un(safety)grounded system?
Keith Cress
kcress - http://www.flaminsystems.com
RE: Approval free alternate energy tie ins ??
I am quite astonished at the open admission that alt power for the grid is unwanted by the utilities.
Guess it has to wait for another time.
RE: Approval free alternate energy tie ins ??
In fact I encurage people who think they can make power cheeper than the utility to go for it.
Just know that regulations and codes hurt us as much as they help us and the same for our customers (Call your congressman now).
RE: Approval free alternate energy tie ins ??
What you you think of a house powered primarily by alternate energy but with an additional device that pulled ( one way ) grid power when it was needed to supplement the alt source. I find it hard to imagine utilities could prevent the installation and usage of such a device.
Comments??
RE: Approval free alternate energy tie ins ??
If you had a break-before-make device the utilities would not mind. But you might very annoyed with it.
Depending on how much supplement you need there is always a IC engine option that would not involve a utility (Maybe natural gas).
The problem here isen't size of your facility, it is the argument that we have to treat all customers the same. It is a legal thing most utilities face.
RE: Approval free alternate energy tie ins ??
Many years ago, (1990), we installed a PV system for a US Post Office building in our local desert. It is still running. It is also inverted, with the required protective relays, etc.... and would be about to pay back, but it is now time to replace some of the equipment,and needless to say, the USPS has no budget for doing is in the upcoming fiscal year. We'll see.
The only residential energy generation systems I've seen as viable are solar water heating, solar charged, battery powered exterior lighting, and other small point of use systems. With some of the DIY installations I've seen, it seems to me that the fewer people we have trying to become their own utilities, the better.
RE: Approval free alternate energy tie ins ??
RE: Approval free alternate energy tie ins ??
Utility companys are granted sole providership, with set limits, and requirments. All parties involved, utility company and customers must accept those limits and requirments.
And all parties must accept that the sole providership was granted to generly reduce the cost of service to the customer.
Times have changed, and utilities, within limits, must accept customer generation. Customers with generation must accept the utilitiy requirments, that have been approved by the regulating body.
My concern here is customers with, and without generation putting so much trash on the power line that the other customers complain to the regulating body.
I also have a beef with wind power because it usually arrives when it is least needed, and defetes the purpose of lower cost energy to the customers.
RE: Approval free alternate energy tie ins ??
Cranky.
One scenario is a alt source generating 140-180 VDC feeding a sinewave inverter and powering household loads. The DC bus is supported by a grid connected, power factor corrected rectifier. Thus no chance of reverse flow and grid support for alternate energy sources. This makes a transparent to the user alternate source that can lower bills when the power is available. Critical to keep the inverter losses low.
""Why is it that people think that they should be able to generate their own electricity and have the power company willingly accept the output with - as far as the proponents are concerned - little or no say about it?""
davidbeach.
Legally i suppose you are right as it makes the utility an partner to an economic transaction they have no control over.
Final note
Why should a consumer be REQUIRED to purchase all his electricity from a government run company. The utility can decide to exit the ongoing transaction if they wish to and this is their right also.
Common sense would dictate that sharing of scattered generation would lower the cost of required new distribution and generation equipment and thus be a source of economic efficiency. The distributed nature of the sources would statistically negate their individual influences much the way this happens with loads. Don't forget that loads are also influenced by weather although at a slower rate due to heat storage within buildings.
In any case i have my answer.
There are no technical blocks to off the shelf alternative energy systems needing no utility permissions, only political and economic ones.
Thanks all
RE: Approval free alternate energy tie ins ??
Why should a consumer be REQUIRED to purchase all his electricity from a government run company. The utility can decide to exit the ongoing transaction if they wish to and this is their right also.
I don't think anyone is required to purchase their electricity form a government, or even a private run company. Set up your own off-grid system and see if anyone cares.
it just happens to be a lot cheaper for the vast majority of users to use a central style distribution system.
RE: Approval free alternate energy tie ins ??
In most areas the power lines and transformers, and meters are owned by the utility, so the utility is involved in any transaction over there equipment (7-11 dosen't give you anything for free).
Some of the problems with customer owned energy sources are the costs utilities are required to pay are more than they are allowed to charge other customers. And there is a rare case where if the total generation on a feeder is equivlent to or greater than from the source substation, it can become difficult to detect a fault on that circuit. Also even if the circuit is disconnected from the substation the ganeration could self support the circuit possibility at some frequency or voltage level other than within the required standards (say lawsuits).
So utilities do have an interest in knowing what customers have that could possibility create problems for other customers. Which is why the normal maximum generation on a feeder is limited to around 10 to 20% of the feeder load.
RE: Approval free alternate energy tie ins ??
Why should a consumer be REQUIRED to purchase all his electricity from a government run company. The utility can decide to exit the ongoing transaction if they wish to and this is their right also."
The publicly regulated utilities cannot exit an ongoing transaction without some sort of cause, such as non-payment. Utilities may be monopolies, but they are regulated as such. You seem to be ignoring this little detail.
RE: Approval free alternate energy tie ins ??
Do I have the right to augment my household electricity with alternative energy without the approval of the Utility.
If you answer NO then I interpret this to mean I have to purchase from the utility.
Do they have the right to cut me off if I choose to utilize some alternate sources to lower my power bill.
If yes I interpret this to mean that I DO have to purchase all my electricity from the utility.
Keep in mind i am not proposing a grid TIE system after the above posts. I am proposing a power augmentation system with NO possibility of affecting the grid other than drawing power from it.
It's technically possible to do.
Lets clear the air about whether the market is FREE or not.
It really is an academic exercise as if I choose to install an augmentation system and the utility cuts me off, a public relations nightmare is in their future.
Headline
UTILITY CUTS OFF HOMEOWNER FOR USING SOLAR POWER!!!!
RE: Approval free alternate energy tie ins ??
If however you push power back into the grid without telling them, and the newer meters will tell on you, they will probally just not pay you for the energy (Or they will give you a stern talking to by someone who thinks he is super (the name super-visor usually dosen't apply).
The usual attitude is pay your bill and don't make waves.
RE: Approval free alternate energy tie ins ??
RE: Approval free alternate energy tie ins ??
Ok that i can live with. I have been told that utilities would not let me install an augmentation system without their approval and i simply think they have no right to prevent me from doing so as long as it is incapable of backfeeding.
As far as grid tie systems i believe that it is technically feasible to create a standard for tie in inverter operation that would negate the need for utility approval, allowing more people to go green. I don't understand many of the arguments against this relating to power quality for other customers as there is no problem with a nearly infinite variety of loads that can produce severe harmonics and high current draws and the grid is mostly a linear system so that pulling or pushing disturbances have identical effects on other customers ( aside from sign difference ).
My initial post was to query methods for doing this but it quickly rattled too many cages for this thread to be productive.
Thanks all
RE: Approval free alternate energy tie ins ??
I think your question was answered both technically and, as a free bonus, politically quite well...
1) Certainly you can do whatever you want within the NEC codes and the more nefarious air quality dictatorships to power your own property. As long as you don't backfeed the utilities. (at this time)
2) Sending a communications signal down every power line in the US to signal an occasional backfeeder's equipment is unnecessary for the results you seek.
3) Yes, a standard national-political and technical inverter front-end for safe backfeeding would go a long way in making smaller solar backfeeders more accessible.
Keith Cress
kcress - http://www.flaminsystems.com