[davegardner]

The same issue exists with grid connected solar panels. My solar panels are designed to stop working whenever there is a power outage. This is a legally mandated requirement here and is very annoying when it happens on a beautiful sunny day.

A solar panel installer told me that if I add a battery backup to my installation, then at least it'll still charge the batteries during a power outage.

[balabaster]

This is the dumbest mandate I have ever heard of. Part of the installation of such power systems should have a mandate that in order for an off-grid power system to be connected to your box, your breaker to the grid must be off before you can enable your off-grid system. Why isn't there a mandate for this?

It seems like the mandate was written entirely to protect the power company's profits hiding behind a thin veil of trying to protect their technicians.

If the electrical utilities cared at all about the customer they'd mandate something that allows customers to do what they want, safely.

What good is charging batteries during the power outage when you can't use them during a power outage? You can't have power connected during the power outage for fear of "electrocuting the technicians" - so what's the point in spending all this money on solar panels if the only time you can use them is while the grid is up... and you have cheap (comparatively) grid fed electricity? What's the purpose in having batteries if not to use them when the grid is down?

[brudgers]

In the US, rural electrification was largely complete 75 years ago. Urban electrification infrastructure dates back even longer. In all that time, intensity of use has increased.

There's a lot of bailing wire and duct tape...or overhead power lines and wood poles if you prefer...in the grid. It's grown based on small decisions over many years. People won't put up with six years of service interruptions while big chunks are rebuilt and debugged...nor will they be happy to underwrite the cost of doing so.

[innguest]

It's BS as you rightfully detected but that doesn't stop the State cheerleaders above from giving us 1001 reasons why this is bad and we must protect the lives of electrical workers, firefighters, and even the lofty goal of protecting the hand-wavy "public commons" itself!

Yeah, it's not the power company's fault for endangering the lives of their workers, it's our fault, you and I regular Joes, for daring to want electricity in case the power company can't supply us with any. How dare you?

[CamperBob2]

This doesn't make any sense. There are almost certainly provisions in the law for backup generators to be connected to the service panel with a transfer switch, either manual or automatic. The idea is that when the generator is powering the house, the powerline service is completely disconnected, and vice versa. This is standard stuff, part of every electrical code I've ever heard of.

If a state legislature doesn't allow backup power to be supplied to a home or business with an NEC-compliant transfer switch, there should be some kind of judicial recourse. I'd spend some quality time with an attorney before taking "No" for an answer.

[balabaster]

Agreed

[jacquesm]

Either your sarcasm tags are missing or you're just simply dead wrong.

I set up a fairly beefy solar/wind powered system in an off-grid configurations specifically not to have to deal with the red tape, installation and insurance requirements of being 'on grid' and I don't regret that but all of those requirements, inspections and gear made perfect sense from an electrical point of view and from a safety point of view.

[jacquesm]

There are some ways around that limitation. The reason it exists in the first place is so that the power company can safely power down their lines without installations such as yours feeding power back into the lines that are supposedly safe. This on the off chance that you'll end up electrocuting a line-man, which makes good sense.

Of course, since your puny little solar installation is incapable of powering a substantial portion of the grid this usually only really becomes a problem when the section that is islanded is small enough.

Some electrical codes allow you to resume powering your own circuit if you physically lock-out your connection during such an outage, and re-configure your inverter to non-grid connected mode.

You will also require a battery in such a case since the stabilizing properties of the grid (it's a very large load and acts as a huge flywheel or capacitor with basically endless capacity from the point of view of your installation).

And of course when the grid outage has been dealt with and you wish to feed power back into the grid again (or consume when the sun is down) you're going to have to undo all of this.

When I built a solar / wind power installation in Canada I decided that the net metering laws and price of power produced by renewables was so low that I scrapped the whole grid connectivity portion and invested the surplus into a much larger battery.

It felt pretty good to have power when the island was down which happened many times every year.

[tlrobinson]

"you're going to have to undo all of this"

Why can't "all of this" be packaged into one idiot-proof box with connections to the grid, your off-grid system, and your house?

[joezydeco]

You mean like a generator transfer switch?

http://www.generac.com/all-products/transfer-switches/home-b...

[jacquesm]

That's a device that you probably don't want to use with your solar installation since it will not handle the grid-present resynchronization at the end of a power outage correctly which could cause your renewable energy system to be re-connected to the grid at 180 degrees out of phase worst case when grid power is restored. The result will be a big bill for a large number of power FETs or IGBTs depending on the tech used in your inverter.

So you can't just add an automatic transfer switch to retro-fit this to an existing inverter, but there are plenty of inverters where an option for an external module can be purchased or where an automatic transfer switch is built into the inverter itself:

http://ww3.wholesalesolar.com/newsletter/MAGNUM-AC-COUPLED-L...

These inverters will first synchronize with the grid before they connect.

[jacquesm]

Depending on local variations in electrical code it can be. But check with a licensed installer familiar with your local code.

[davegardner]

Yes it's not such a problem when it's just my 5 KW system. However here in Perth, Western Australia there are a lot of sunny days, so domestic rooftop solar systems are very commonplace now.

In my case there's some significant financial incentives to stay connected to the grid (I actually get a cheque from my power company for most of the year). That'll change in another 6 years time when this higher buyback rate expires, so I'll be looking very closely at whether I want to remain grid connected at that point.

[maxerickson]

That's allowed in Connecticut:

http://cga.ct.gov/2011/rpt/2011-R-0390.htm

$300,000 liability policy requirement right at the end there.

There's also similar rules for installed generators, it's not clear to me how they would treat a big battery.