Sort of related, anyone know if the utility company can determine the amount of energy consumed during that multi week period between solar equipment install and when the utility company installs the new meter? I'm thinking they just estimate power use from previous use until they install the meter.
Got Busted by Electrical Power Police..Now Need help with Permits
- Thread starter Larry185
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And this gets me. Why do some vendors advertise their ULtested wares as being the same as UL Listed! They are not the same.
Is UL tested and UL listed the same thing? How does each come into play when dealing with our utility providers?
As long as you are not exporting (and maybe importing a minimum level) they are unlikely to have a system to flag accounts. Simple example: when I go on vacation my average daily consumption drops from ~30kWh to ~15kWh after 24h. Likewise, it is perfectly legal to support an appliance via an alternative source of power for part of the day, or to just unplug it.
Specific to determining consumption, the meter still operates. Your PTO is typically not in place until the new meter is installed, so if the meter over-charges you for exporting power that is your problem and not theirs.
Cyanlite
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It's not the same thing.
Utility companies aren't your local AHJ. They can (and probably do) have an approved list of equipment/inverters that they will allow to connect to the grid. If you think your local county permitting office is strict, just wait until you encounter the electrical engineers at the utility company.
If you're off-grid, then UL "tested" may get you through with your local AHJ. Every locale differs, but I think you'd get laughed out of the room by your utility if you try to show up with a grid-tied inverter without the full "UL Listing" that they can verify in the UL database. They also will probably frown upon DIY work.
Source: I called my utility and AHJ about doing a DIY grid-tied system and got laughed at.
BradCagle
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If you have appliances that come on by timer (think pool pump), or contactor (think AC Condenser unit)
Wire your grid tie inverters in behind the contactor where your AC Compressor is tied. That way you only grid tie when the compressor is on, and you're guaranteed the AC Compressor, and Condenser fan will use up all your solar power.
Wire your grid tie inverters in behind the contactor where your AC Compressor is tied. That way you only grid tie when the compressor is on, and you're guaranteed the AC Compressor, and Condenser fan will use up all your solar power.
dianea
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I'm sure any of the utility workers in the area on a daily basis have a sharp eye on my off grid system to make sure it isn't connected in any way or affects safety of anyone. I would do the same. I work with megawatts of power maintaining manufacturing plants and constantly aware of what could go wrong and how serious even a small incident can get. Utility workers have to repair things that go wrong due to mistakes and see non UL listed items all the time. I doubt it was neighbors.
The PV rapid shut down disconnect should be open until the two way meter is installed, as the system isn’t certified to generate until the meter is set.
Problem solved
PlaneBatteries
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You can find out easily by signing into your power company account and see if the have a usage " dashboard" where you can see your daily and hourly usage.
The power company that supplies my Cabin in TN provides detailed stats of consumption down to the minute online. Neighbor tried a grid tie one weekend. Power company and sherif was there in about 30 minutes from when neighbor fired up the inverter. They made him disconnect and gave him a hefty fine.
I have an old meter in a rural area and I can view my hourly usage online
Who is your power company? I know with the one in my state, you can have 1kw or less without an interconnect agreement and be grid tied. Your two 290w panels couldn't put much out. Several days later they were at your door?
Can someone explain what is the point of tying to grid anyway without an agreement? If you're looking to offset your bill just run your loads off grid that way you don't get charged for the portion you don't use from your utility. Trying to tie to grid, even if its just for a test seems to be not only waste of time, but it can get you in trouble in a lot of different ways.
Free battery (not that I condone it). Take a refrigerator as an example-- it has a 50% duty cycle, so if you use a solar panel for it it will only get 50% use; worse actually since you need to handle compressor inrush.
It is easy to not export on a 15-minute basis, but real-time is nearly impossible.
12VoltInstalls
life passes by too quickly to not live in freedom
Because people read stuff about the meter running backwards and think they can do it.
The ‘post-modern’ way of guerrilla solar is a “gti” that contributes to wattage being consumed and thereby reduces the electric bill. The payoff period makes that a little bit impractical on one hand (solar costs a lot compared to kWh rates) and if/when consumption drops to below the gti output, woops! the powerco comes calling.
I’ve got one installed on my friend’s barn but they aren’t very efficient (6 or 7 freezers) and with ~250W max from the panels and their fish tank and other loads it’s unlikely to overpush. For $250ish of stuff it’s “paid back” maybe $20 tops since January.
The better/right way is a zero-export inverter or aio designed for that application
Cyanlite
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Running off-grid requires more transfer switches, disconnects, bigger inverters, fuses, circuit breakers, more batteries, and major rewriting of your house’s electrical system. Permitting sucks, because more often than not the AHJ doesn’t have a clue what’s going on if you try to DIY.
It’s super tempting just to plug in one of those Chinese inverters that backfeeds a circuit with a suicide cord directly to a wall outlet. Sure, you’ll probably burn down your house, get someone electrocuted, or get in trouble with your utility/law enforcement, but it’s the simplest approach. Literally the path of least resistance since it’s one cord.The Off-Grid Basement guy does this on a smart relay and works well for him as an energy dump.
12VoltInstalls
life passes by too quickly to not live in freedom
That is not accurate
Cyanlite
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Which part? Backfeeding your panel with your grid turned on (without an interconnection agreement) is a crime in most states. You can easily get a lineworker killed.
Ampster
Renewable Energy Hobbyist
I have researched and not found a criminal statute in California. As a general statement, creating a hazard to linemen when the grid is down is probably covered under some statute. But when the grid is up, there is no hazard to linemen. Using a zero export GT inverter seems to be more common and perhaps it is a matter of time in which that scenario will probably be covered in some fashion. Your mileage may vary.
To be clear and consistent with the topic of this thread, there are clear statutes almost everywhere in the US that cover the construction of electrical circuits. As long as one constructs those in accordance with the building codes there does not appear to be any prohibition about generating your own power.
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newbostonconst
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Even when the grid is down I highly doubt you can back feed the grid enough to keep the inverter running for more then a few tenths of a second before the in inverter implodes....you are pretty much powering into a dead short....you are trying to power your whole neighborhood....
Thus the risk to a line worker is nill...
Energy price rises in US? in Europe is expansive that offgrid is cheaper than grid.
If feed in to the grid is no allowed, you must go offgrid.
You may tailor your system in accordance of your needs, conductors cross section must be adequate.
I use a quite hi voltage to avoid thick expansive conductors.
If you live in crowded neighborhood fire hazard is a real concern, but can buy cheap land and go truly offgrid.
If feed in to the grid is no allowed, you must go offgrid.
You may tailor your system in accordance of your needs, conductors cross section must be adequate.
I use a quite hi voltage to avoid thick expansive conductors.
If you live in crowded neighborhood fire hazard is a real concern, but can buy cheap land and go truly offgrid.
Ampster
Renewable Energy Hobbyist
I have heard it described as an iinfinite load which may be the same thing. A true GT inverter would disconnect as soon as it loses the grid but I am not clear what an off grid inverter would do? Most likely, as you suggest, it would implode.
Nobodybusiness
Solar Sponge.
Even way out here in the sticks the meter we have is minute by minute poll.
I assume it’s via Cell polling.
ncsolarelectric
Engineering Support CEO
Not true! Part of the IEEE 1547 standard is testing the anti-islanding function on a 60Hz resonant circuit. In the real world, it's possible that the "neighborhood" load resonates at 60Hz, and keeps right on going for longer than the standard allows due to stored energy "elsewhere" in the circuit. The illegally connected inverter just keeps it going for longer.
ncsolarelectric
Engineering Support CEO
It goes into current limit and shuts itself down. However, some of them attempt to auto-restart and that's when a lineman, who has disconnected the line outside your house from the "neighborhood" while looking for the problem, gets shocked as the inverter attempts to restart itself.
