Net metering Cap

Burno "micro gridding" is called "islanding" in the solar industry. This is how we have designed our solar system and we should see a payback between 3-4 years. It is a 27 panel, approx 7kw system with a grid-tied inverter and a island battery inverter/controller. When the grid goes down the island inverter kicks in and continues to allow the panels to produce electricity and pull stored energy from the battery bank (48v, 400amh array). Without the island inverter, when the grid goes down your system also goes down.

Sorry my friend, but "Islanding" in the solar industry is what UL1741 does not allow. The term "Islanding" is when the grid goes down but energy is still backfed into a down grid. Not allowed. The term " micro grid" is when the grid goes down but a battery based off grid inverter sends 240vac back to the grid tied inverters through AC coupling so that the down grid is out of the loop. The grid tied inverter never knew the differance as it still has 240 vac. Meanwhile the panels keep the batteries charged and supply electric to any loads being used. Excess electricity is put into a dump load. It could be that you have a SMA Sunny Island off grid inverter and that's where you got the term. Hope this makes sence.

Going slightly off-topic: Traditional batteries can be expensive, environmentally messy, and impractical for large-scale energy storage. Some large-scale alternatives include underwater air bags (filled with gas by day, and decompressed by night), gravity potential energy storage (move water or solid mass uphill by day, and lower it to drive generators by night), and cryogenic transfer (heat a mass by day, and draw the heat out by night).

Related links, and additional ideas:
http://en.wikipedia.org/wiki/Compressed_air_energy_storage Compressed_air_energy_storage
http://en.wikipedia.org/wiki/List_of_energy_storage_projects List_of_energy_storage_projects
http://en.wikipedia.org/wiki/Hydraulic_accumulator Hydraulic_accumulator
http://en.wikipedia.org/wiki/Cryogenic_energy_storage Cryogenic_energy_storage

Bruno you're right. Thanks for correcting me. Yes, I have an SMA sunny island so I guess I was confusing the term with their marketing of the product. Found a good wiki on islanding too... so maybe what I was referring to is "intentional islanding?"
http://en.wikipedia.org/wiki/Islanding

Ya, energizing the grid, while it is down is a big no no... could cause damage to your neighbors and possibly harm power workers. The SMA sunny island kills the connection to the grid when it detects a power loss from it. It then uses a transformer to upstage the battery power from 120 to 240 so the sunny boy (the panel inverter) still "thinks" the grid is up and continues to supply solar power to the house.

Love technology 🙂

Our system is designed as a full off grid system, but we designed it to have grid-tie to supply "unessential" luxuries such as pool heater, cloths dryer, electric range... that would demand too much from the solar by it's self. New A/C split units are so effecient now we can run our master bedroom one on our batteries alone for days if we wanted too (but we wouldn't 😉 )

Our system is designed as a full off grid system, but we designed it to have grid-tie to supply "unessential" luxuries such as pool heater, cloths dryer, electric range... that would demand too much from the solar by it's self. New A/C split units are so effecient now we can run our master bedroom one on our batteries alone for days if we wanted too (but we wouldn't 😉 )

how much do you pay wapa a month?

$0

We pay $6 service charge.

We pay $6 service charge.

Correction. $22 credit this month8-)

Well WAPA asked for it and we now can give it to them! 53 cents/kwh is INSANE! And the government isdoing anything about it. And forget about Hodge. He is out for one thing, MAKE MONEY FOR HODGE.

I put in 13 enmphase panels two years ago. Now I have just installed, MY SELF, 28 more centralized inverter. These produce around 30 -35 A DAY. The cost? 11K with a 30 tax refund.

So my advise is it you are handy then install solar. AND SCREW WAPA!

Bill

Interesting development on different rates for those below 5Kw and above 5K -500Kw...

http://stcroixsource.com/content/news/local-news/2014/04/17/net-metering-changes-move-forward-senate

Interesting development on different rates for those below 5Kw and above 5K -500Kw...

http://stcroixsource.com/content/news/local-news/2014/04/17/net-metering-changes-move-forward-senate

I don't see how this change will do anything for anyone other than WAPA.

Kudos to those with solar power. Crazy not to have even a few batteries so that you can get back up power for essential appliances during an outage. Remember fossil fuels use harms the environment and atmosphere more than a couple batteries. And you don't have to have a massive system or be totally off grid.

Thanks to senator Barshinger his new legislation will provide modest income citizens the ability to participate by renting roof or hard space for panels. They will not have to compete with large corporations who hog available mW capacity.

Blaming homeowners for producing "too much" and requiring the use of batteries to smooth out load is a cop-out.
Power companies must be able to compensate for increased (cloud cover for instance) or decreased demand. And you can't do that with a few very large antiquated power plants running on fuel. Takes too long to come on-line and those are hard to modulate. So instead of blaming individual producers, it would be much more productive to consider options:
- purchase power from elsewhere (not an option in St. Croix)
- micro-power plants capable of firing up rapidly (natural gas for instance)
- demand-response where key consumers agree and equip themselves to reduce their consumption upon an automated request from the power company (like cut off A/C in government buildings...)

Blaming homeowners for producing "too much" and requiring the use of batteries to smooth out load is a cop-out.
Power companies must be able to compensate for increased (cloud cover for instance) or decreased demand. And you can't do that with a few very large antiquated power plants running on fuel. Takes too long to come on-line and those are hard to modulate. So instead of blaming individual producers, it would be much more productive to consider options:
- purchase power from elsewhere (not an option in St. Croix)
- micro-power plants capable of firing up rapidly (natural gas for instance)
- demand-response where key consumers agree and equip themselves to reduce their consumption upon an automated request from the power company (like cut off A/C in government buildings...)

wait a sec.....

Power companies must be able to compensate for increased (cloud cover for instance) or decreased demand

why *MUST* they? this entire post is very "entitlement" mentality... the power company doesn't have to do any of this,, the fact that there is ANY net metering is pure charity/kindness of the power company. In fact it's so difficult to allow that Hawaii and California are cutting back / canceling netmetering programs all together due to the stress on the power infrastructure.

anyway, if I missed out; too bad for me... I dont blame WAPA (except for the idiotic allocation of 10mwat to STT and 5 to STX) being off grid is probably the better idea.

http://www.instituteforenergyresearch.org/2014/01/14/net-metering-101/

Here is an interesting primer on net metering.

@liquidfluoride: issues in California are related to the grid designed for centralized power plants rather than a widely distributed network of smaller producers. STX is fortunate to have a small and pretty good/new grid.

In exchange for being a monopoly the charter of a power company is to provide as much power as demand requires. Talking about an "entitlement" mentality, regulators clearly failed on their job by allowing WAPA to charge 55c / KWh.

Further a "public" utility should support renewable energy because, well, it is in the public interest. Sun, son, more sun to paraphrase the infamous "drill" quote. It takes a new mentality, or more precisely new technology that already exists, including:
- Demand-response automated systems where key consumers reduce their load on the grid. Inexpensive and simple.
- Micro-generators that come on line (and offline) rapidly.

There is only one aspect for net-metering that is unfair: WAPA purchases at the same price they sell. That doesn't reflect their cost of maintaining the grid, meters and managing the billing.

@liquidfluoride: issues in California are related to the grid designed for centralized power plants rather than a widely distributed network of smaller producers. STX is fortunate to have a small and pretty good/new grid.
.

well, I'll give em one thing, I've only had 3 power outages in 2014, compared to never anywhere else I've lived; they are good at making a "new" grid look like crap.

maybe wapa could be more flexible than other grids, but the way they handle business makes me highly doubt that. more proof that governments should not run anything.... ever.

So what happens to the solar companies on STX now?

I would imagine most folks would want a grid tied solution, not stand alone. Is that now not possible at all give the cap for net metering has been reached, or can you still be grid tied and just loose out on any credit for excess?

Good question IslandHops...

So what happens to the solar companies on STX now?

I would imagine most folks would want a grid tied solution, not stand alone. Is that now not possible at all give the cap for net metering has been reached, or can you still be grid tied and just loose out on any credit for excess?

As I understand it, Once the cap is met, they either expand on it or shut down further net metering. Which means batteries and off grid installations.

The solar companies are about to be weeded out. The strong should survive if they sharpen their pencils and don't get greedy.

So what happens to the solar companies on STX now?

I would imagine most folks would want a grid tied solution, not stand alone. Is that now not possible at all given the cap for net metering has been reached, or can you still be grid tied and just loose out on any credit for excess?

As I understand it, Once the cap is met, they either expand on it or shut down further net metering. Which means batteries and off grid installations.

The solar companies are about to be weeded out. The strong should survive if they sharpen their pencils and don't get greedy.

So much for employment for all those young people the government paid to train in the solar industry. I can't see many companies surviving doing stand alone non-grid-tied solutions - unless there are great strides pending in battery capacity/cost reduction.

You can still have solar and be tied to the grid without batteries. You won't have the cost benefit of net metering, but at least you have your daylight WAPA savings.

Just saw that OK can charge their customers that have wind or solar more than customers that don't.
Hope Hugo doesn't hear about it!

WAPA is inviting itself to a lot of expensive legal issues should they decide to ban additional residential grid-tied solar panels.
- Class action suit from homeowners and solar companies.
- Threat of federal penalties (pullback of any subsidy) -- that's how I got mine connected long ago stateside when my country and utility were putting hurdles all over.
- Or at an insane 55cents / KWh, a monopoly and no longer any alternative, wouldn't that be the perfect combination for a RICO injunction?

Sign on the STX Building Permits Office door today reads "We are no longer accepting net metering permit applications until further notice, management"