Florida Power and Light: Regulations for home solar installations

The article is trying so hard it's hard to tell what the actual issue is.

It is dangerous to backfeed the grid -- you may kill the line worker coming to fix a blown transformer or downed line.

In some places a grid connection is considered necessary by the building code. If so, you must use proper equipment.

I work in the solar industry and can confirm that this is standard safety practice in my state as well. When grid power goes down the inverter is required to shutdown and remain off until a few minutes after normal grid conditions are restored. This is to ensure that the grid equipment is actually de-energized so it can be worked on safely. It's such a ubiquitous policy that all inverters need to be UL Certified to prove that they do this.

Utility companies pull a lot of bullshit, but this policy is actually pretty sound.

If you want to use your PV as backup power, you need to treat is as you would a conventional backup generator and install a manual transfer switch that that isolates disconnects the electrical service as the backup power is engaged. This can nearly double the cost of the solar project, so most people don't do it.

This reddit comment thread [1] explains the issue well.

In short: most households get grid-tied solar power setups with no batteries. If the main grid is off, it creates islands of power where the units can't safely backfeed to the grid. However, you can legally get a battery setup which costs more money and use that when the grid is down.

[1] https://www.reddit.com/r/Futurology/comments/70oz3k/due_to_e...

This seems to be straight from a dystopian movie or book I'm not sure it isn't a joke. Is the "get off my lawn" a thing of the past in US? What business have US gov, or anybody else for that matter, to do with what I do on my property?

The stuff about the bi-directional meter is warblegarble.

What the requirement is talking about is operating a grid tie system before FPL upgrades the meter to one that measures in both directions in a way that meets their requirements. This is a sensible requirement, not a ginned up excuse.

(all the quotes are coming from a linked grid interconnection guideline https://www.fpl.com/clean-energy/net-metering/guidelines.htm... )

I wonder if there is actually any legal requirement to have a grid interconnection. The article isn't real convincing.

Related to the website, not specifically the story: http://explosm.net/comics/3557/

You have to design the system correctly so it does not backfeed grid. https://goo.gl/iw8f8w Look at the marketecture from solar edge. You can add in a generator with a automatic transfer switch. They also highlight a scenario with existing PV and a separate grid tie inverter.

Isn't it necessary to have the grid as a backup consumer? What happens if you over produce solar energy, but don't have the necessary means to dissipate it?

You need to design system correctly. Look at literature from solar edge. You could also add generator with automatic transfer switch. Also, you can modify existing system. https://goo.gl/iw8f8w

In 2015 about 10% of Hawaii's residential customers had solar installations (0.5% is the national average). Such a large intermittent source of electricity caused problems for the utility companies and led to limitation on buying back electricity from these solar installations. Naturally, this has slowed installation of additional residential solar in Hawaii. See [1] and [2].

Hawaii has a goal of 40% renewable by 2030 but they have a number of technical hurdles to get over.

[1] http://e360.yale.edu/features/will_new_obstacles_dim_hawaiis...

[2] http://www.utilitydive.com/news/hawaiian-electric-opens-20-m...

Do they have the authority to enter your home and check what kind of power you are using? What does it stem from? Can you shoot them for trespass?

The same thing WRT rain water which is mentioned in comments.

To me it seems like an unreasonable invasion of household borders: trying to regulate something confined in a household.

In Africa we've built small home/lab/datacenter power systems that charge a battery bank off utility mains plus on-site generation. It's basically a gigantic UPS that can automatically switch among a variety of power inputs. What's stopping someone from building something like that here in the U.S.? Charge batteries from solar, supplement with mains power, maybe even add a diesel generator for extreme emergencies, and use an automatic transfer switch to prevent backfeeding the utility mains (which is super dangerous to line workers and probably the reason for Florida's regulation). Not being a power systems guy myself, I don't see where the flaws in such a design are. Any EEs out there who care to comment?

When generating emergency power is outlawed, only outlaws will have emergency power.

I can't see how anyone would think this was a good idea. I expect respect for the law to plummet faster than you can say "Dad. Can you please give us non-rotten food?"

I'm waiting for someone to justify this with a warped sense of "economics".

Rather, thanks to regulation it is illegal to power your home with solar panels in Florida. Lobbyists are not legislators.

That said, power grids are incredibly difficult to coordinate, there is almost no describing it. You need extra installed capacity if some endpoints are also generating stations.

Personally I would not really want to backfeed to the grid anyway, so if this regulation applies even when you don't hook up to the grid, that seems pretty ridiculous.

Either way it doesn't seem like you'd need laws to keep people from hooking up their panels to the grid, unless they need to cancel out a law that says they must be able to hook up their solar arrays to a grid.

I can see an opportunity here for the grid to become owned/operated by the people, not massive corporate greed machines. A house who has excess sells it to neighbors who do not have the solar capacity where neither are connected to the normal grid. Throw some technology into automatically shutting down the generator side every X hours unless its given authorization wirelessly. This foolproofs the root cause of uncontrollable distributed hot lines.

ok, so its illegal to power your home with solar... but is it illegal to charge a battery with solar in Florida?

Powerwalls would still be viable and legal right?

This is what happened in Spain too.

TBH I think it makes sense that all houses should be connected to the electrical grid. Just like all houses should have proper sanitation facilities.

This is a small edge case for people who want to be self sufficient even though it makes no economic sense, as FPL does have net metering in place.

If they didn't have net metering in place I'd understand this, but considering they do and at first glance looks like a very reasonable program, is it really worth altering city and state building codes to allow it? The city/state would have to pay for very expensive specialists in off grid solar/battery/inverter setups to ensure they were at parity as a simple grid connection.

Since the original, hyperbolic article is no longer linked, This post is to give some technical background on home electrical systems in the US for understanding of the underlying considerations of how secondary home power sources should operate. First two points of context:

1. The United States does not have a uniform electrical code, but instead has a document called the National Electrical Code (NEC) published regularly by the National Fire Protection Association (NFPA) as NFPA 70. The most current version of the code is from 2017. Looking inside out, the NEC stops at the main electrical service input to e.g. a house, and from that point a different code, called the NESC, takes over.

2. There are a wide range of variants of the NEC that are codified to force of law throughout the United States. And states/cities/municipalities can exempt and/or add to their preferred version. Here inside City of Atlanta boundary, for instance, we are on the 2014 version of the code. But even then there are different versions of the code in force at different locations in the multiplex.

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With the caveats that not everything below is 100% uniform everywhere in the US, here is how wiring in US homes generally works. There's a few steps here, but it should all make sense:

A. There is a stepdown transformer with a "center tapped" secondary configuration. The end result of this is that homes are fed with two energized conductors ("hots") and a "grounded" conductor colloquially referred to as the "neutral." The two energized conductors are 240 Vrms apart, and each energized connector is 120 Vrms to the neutral (i.e. grounded conductor). Hold the idea that these three wires terminate on the incoming side of the main panel for items B, C, and D.

B. The wall outlet in a typical US house, colloquially called an "Edison" receptacle has three conductors. Those are an energized conductor (hot) the grounded conductor (neutral), and the "Equipment Grounding Conductor" (EGC). The latter is a green wire commonly referred to as "ground." Under normal conditions the EGC (ground) carries no current, because it is not a part of the electrical circuit between hot (energized) and neutral (grounded) connectors.

C. Now imagine that you have a wiring problem inside your table saw, and as a result the outer surface of that saw becomes energized. That surface is "bonded," i.e. conductively connected, to the EGC (ground). So if the surface has suddenly has a voltage on it, a large current then flows back through the EGC to the main panel. This is because the EGC is a low resistance path. This sudden surge in current causes the OCPD (i.e. "circuit breaker") to open. This disconnects the energized conductor (hot) feeding the table saw.

D. At the main panel, and only at the main panel, the EGC (ground) is connected (bonded) to the neutral (grounded conductor). This is so that the current from the EGC has a return path. In this case it goes equipment fault -> EGC -> EGC to neutral bond in main panel -> neutral coming into main panel from street -> center tap of secondary on the outside pole transformer. The winding of the utility pole secondary then completes the circuit with low resistance, insuring the OCPD (breaker) opens.

E. Note that neither the main panel "grounding/earthing," technically called the "grounding electrode conductor (GEC), nor any similar grounding/earthing (i.e. connection to physical earth) of the center tapped neutral at the utility pole play a role in the low impedance path for current that opens the circuit breaker. In fact, the earth is specifically excluded as a "ground fault current return" path by NEC 250.4(A)(5).

F. Any utility is concerned with essentially two things when it comes to secondary power at the house: 1)Feeding electricity back to the grid while their workers are making repairs/upgrades. 2)maintaining a singular low impedance "ground fault current return" path in the home at the main panel electrical service entrance.

G. Point F is why there are subtleties about what can be tied to the grid, and how the secondary "renewable generator" must behave in the event that it is exclusively providing power while the utilities' transformer is physically disconnected from the residence at the service entrance.

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Beyond points F and G are lots of subtleties around sub panels, secondary current return paths, GFCIs, "floating neutral" generators, transfer switches, ground field impedances, etc. It is a surprisingly big topic, but I'm happy to try to answer specific questions.

If this is a joke then it belongs on Reddit /r/jokes - if it's not a joke it belongs on /r/LateStageCapitalism

Lobbying should be made illegal

Hysterical article is hysterical?

The actual laws are more reasonable:

"Renewable generator systems connected to the grid without batteries are not a standby power source during an FPL outage. The system must shut down when FPL's grid shuts down in order to prevent dangerous back feed on FPL's grid. This is required to protect FPL employees who may be working on the grid."

Note the "without batteries" exclusion a similar exclusion applies to the cutoff switch when the grid is down, to protect line workers.

https://www.fpl.com/clean-energy/net-metering/guidelines.htm...

The title of this article is quite misleading. It's not saying that it's illegal to have solar panels powering your home, only to have a solar system that does not tie into the grid. Then making it seem that requiring anti-islanding protection is some act of malice.

Wait ... all that is says is that if you back feed into the grid, that you have to have a system shut-off. That's common in all southern states as far as I know? It's basically to protect utility workers that are working on electricity in the area so they don't kill themselves. It makes perfect sense and they have the ability to come in and turn your power off, naturally when doing so. Am I missing something?

Not conspirancid related - but a real problem. If there is a fire, solar panels produce power while preventing water from reaching the roof - and electrocute fireman. How to solve?

In today's news: USA being USA

Hope power prices don't spike too much, or else this law will backfire pretty quickly.

You can point fingers and say it was them lobbying, but everyone who didn't do something to act in the opposite direction could have influenced but didn't.

I say this not to blame more but to motivate people to take responsibility and to act, to stop people from thinking they're powerless (no pun intended).