BajaNomad

grid tie solar systems

capt. mike - 11-6-2009 at 04:57 PM

anyone here done a grid tied PV system for their mexican property?
by grid tie i mean no batts (unless you wanted stand by power).

just curious if CFE was allowing inverter back feed and using your own PV generated power even if you COULD tie into their power system at the SES and meter.

BajaNuts - 11-6-2009 at 09:23 PM

Hey Capt. Mike,

I'm not sure why the question, but usually the grid-tied systems (net metering etc) is coupled with rebated from local utility companies. Credits on your power bills, etc.

Feeding back onto the grid is different than having a back-up solar panel.

I believe that NOB, in some areas you can have a solar panel that feeds into your house on a separate meter and homeowners can get a credit on their power bill for the solar energy they produce.

And then there are other systems that do actually feed back out onto the power grid. That whole technology is a mystery to me, but it is out there. I just can't help wondering how that works in a power outage when the main lines are down and the linemen are working on the lines (which should be dead/no power) and someone's solar panels are backfeeding the main grid's power lines,??????

I have no actual knowledge if there is a solar energy credit program in Mexico (but I doubt it).

And If someone did have a solar system without batts, why would they send their excess back onto the grid?

Is there a reason or scenario you are asking about?

'Nuts

TEQUILA4EVER - 11-7-2009 at 01:05 AM

Hi Captain Mike -

Grid-tie PV has been my job ever since -
in Germany -
Here in MX/Los cabos area/ I set up only a few but I can tell you it is quite a procedure to get it approved .
Since there is no govt. incentive the return of your investment will be well beyond 20 yrs .
Only in case you suffer from CFE-tariff DAC (domestico de alto consumo) you may have the chance to recover your investment after 9 to 12 yrs by droppinng out of the DAC down to tariff 01 .
Far better option would be using one or a pile of these new stackable mini-grid-tie inverters that you plug into the wall-plug/socket to lower your utility bill without notifying local CFE bigheads .

Cheers
Rolf
Tijuana cell-phone 664-2277107

LOSARIPES - 11-7-2009 at 04:25 AM

Tequila4ever:
"Far better option would be using one or a pile of these new stackable mini-grid-tie inverters that you plug into the wall-plug/socket to lower your utility bill without notifying local CFE bigheads"

What is that?

capt. mike - 11-7-2009 at 08:37 AM

thx Rolf. yes - those are starting to show up but inventories are non existent as it is so new and the one mfg i am familiar with is 6 months behind in inventory thx to one outfit that pre ordered 3000 times expected initial demand - they way underestimated potential sales.
but....the power companies are now wize to the scheme and are working tripple overtime to get them banned. or regulated to the point that they are not economically feasible.

i think at about 600 watts per module i'd want about 8 of them plugged in now!!:light::bounce:

jorgie - 11-7-2009 at 08:43 AM

Mike , for what , for why ?

Grid Tie Inverters

bajaguy - 11-7-2009 at 08:44 AM

http://www.ecodirect.com/Grid-Tie-Inverter-s/38.htm


I think....................

[Edited on 11-7-2009 by bajaguy]

capt. mike - 11-7-2009 at 09:10 AM

"And then there are other systems that do actually feed back out onto the power grid. That whole technology is a mystery to me, but it is out there. I just can't help wondering how that works in a power outage when the main lines are down and the linemen are working on the lines (which should be dead/no power) and someone's solar panels are backfeeding the main grid's power lines,?????? "

can't happen. the inverter HAS to shut down in a fraction of a second if the power co grid supply EVER goes down to protect against just the scenario you speak of. No chance of feeding from the DC supply side of the inverter and make AC for the grid if there is ever a problem on the grid supply side being fed from the home's DC made power.


"And If someone did have a solar system without batts, why would they send their excess back onto the grid?"

only if there was a net metering incentive or a buy back Rider like available in many states elec companies. otherwise use what you make while you are making it. if you make too much and CFE will not take it you have to shunt it to a dummy load.

"Is there a reason or scenario you are asking about?"

yes. i am working on several possible PV and thermal deals in AZ and want to branch into Mexico either on or off grid situations. And.....i hate batteries.:light::lol:

BajaNuts - 11-7-2009 at 09:33 AM

Bajaguy's link is a pretty good explanation of grid-tie-inverters. We are just starting to research this technology for ourselves.

I should have edited my post to say "why would anyone send it back onto the grid WITHOUT GETTING COMPENSATED from the utility or CFE"...
I suppose the dummy load is the only reason for sending it back onto the grid without compensation.

WA state is one of the states that has mandatory refunds/credit for people with net metering. In our local area, which has lots of sun, the local utility restructured their rates and many people's bill doubled. It went from a basic charge of $29/month to $53/month. Net metering is going to blossom here...

TEQUILA4EVER - 11-7-2009 at 11:54 AM

Hi Losaripes -
that's a new kind of grid-tie inverter to be mounted between solar panel and wall-plug . You don't have to pass all the CFE permission procedures and feed the sloar electricity directly into any socket of your house .
You can use as many solar panels and accordingly inverters as you like - just make sure you don't produce more solar electricity than you need because CFE does in no case pay your overproduction .
cheers
Rolf

LOSARIPES - 11-8-2009 at 03:52 AM

Hi Rolf,
Thanks for your call.