[RE-wrenches] Outback with grid charging

Jesse Dahl dahlsolar at gmail.com
Sat Aug 25 22:43:09 PDT 2012 

We dropped the gird using the HBX like Phil mentioned and allowed the wind to charge.  It took 4 hours for the loads to drain the batteries to LVC.  I thought the charger would wait an hour and then search for grid to charge, but it never did.  Either way, it got the point across to the homeowner that:

1) very poor RE resource 
2) poor load analysis
3) unfortunate the contractor didn't sit down with them and discuss this

Jesse

Sent from my iPad!!!

On Aug 25, 2012, at 2:07 PM, Phil Undercuffler <solarphil at gmail.com> wrote:

> Sounds like a case of bad design, misrepresentation to the customer
> and not understanding the equipment.
> 
> If they have FX3048T inverters, they cannot sell excess RE generation
> (and I'm going to be gracious and set aside for a moment any
> assumptions about the installation of these particular turbines, or
> ability to produce RE power) to the grid.  Therefore, they either can
> operate the protected loads "off-grid" by using the HBX mode to drop
> the grid, cycling their batteries, and hopefully charging them from
> the wind's input.  Alternately, they can put the inverters into backup
> mode to protect the downstream loads from a utility outage.  That's
> probably what they are doing now, as it's the default when that
> inverter sees an AC input. The offgrid FX assumes the AC input is
> generator, so figures if you're running a genny you don't want the
> charger to go silent.  The batteries are at float, and the turbines
> are producing squat -- and that's not because of tower height or
> siting or turbine quality, it's because the batteries are full and the
> loads are being supplied by the grid and there's nowhere to put excess
> energy.
> 
> You can cycle the batteries and pray for enough RE generation to keep
> the batteries charged. Or float the batteries and let the turbines be,
> well, yard art.  If you can't sell the power back to the utility, the
> batteries will sit in float and the RE generation will go into
> regulation.  Or you can swap out the FX for GTFX inverters and sell.
> The GTFX inverter has the additional advantage in it "knows" the AC
> input is grid, and won't float the batteries from grid power.  That by
> itself will reduce the AC consumed from the utility.  Plus, you get
> the benefit of selling the great excess RE.  If you don't want to go
> full-bore utility-interactive the Radian has an additional capability
> to "offset" utility power with RE power and not cycle the batteries,
> but it's generally better to be utility interactive whenever possible.
> 
> Mainly it sounds like a matter of figuring out what the client wants
> to achieve, and then setting up the right equipment in the best way to
> get that job done.  The last handful of guys didn't do that, hopefully
> you will be able to help them understand this, and then make this
> system right.  And get it in writing.
> 
> Best wishes for this,
> 
> Phil
> 
> 
> 
> 
> On Fri, Aug 24, 2012 at 7:39 PM, Kent Osterberg <kent at coveoregon.com> wrote:
>> Jesse,
>> 
>> Sometimes the best thing you can do for a customer is document, in writing,
>> what's wrong. And walk away if they aren't willing to fix it.
>> 
>> Kent Osterberg
>> Blue Mountain Solar, Inc.
>> www.bluemountainsolar.com
>> 
>> On 8/24/2012 6:36 PM, Jesse Dahl wrote:
>> 
>> Im with you on the wisdom of it.
>> 
>> The problem with my area is that people maybe good a grid tie, but there are
>> very few people that understand the off-grid applications (DT is the only
>> person I think is worth listening to.)  The contractor they chose was the
>> only contractor the home owners spoke to that lacked any type of
>> certification, not that that means anything.  The homeowner told them what
>> they wanted to do and the contractor said okay.  Even though it was a poor
>> idea.  I was shown email conversations between the two.  Of course there is
>> always two sides to these stories...
>> 
>> The system was supposed to use two wind generators to charge two battery
>> banks and then feed to FX3048 Outback inverters.  Both inverters were also
>> tied to the homes panelboard to help charge the bank in-case of low wind.
>> The two Outbacks fed a 100A panelboard that had a few loads from the home
>> wired to it (well pump, furnace, sump, various receptacles)  The panel also
>> has a bypass switch that allows it to bypass the inverters all together and
>> use straight grid power to run the loads.
>> 
>> The homeowner supplied the wind and the controllers, the contractor supplied
>> the inverters and electrical BOS and the 16 MK 12V batteries.  Another
>> contractor came up to program the setpoints.
>> 
>> I have mentioned jobs like this before on the list, and I keep finding them
>> up here,  its getting a little old.
>> 
>> I told them today to get both generators up to at least 80 feet or to scrap
>> both a install a 4kW array.  I also said if the want to hire me, what I say
>> goes and if I say it all comes out to start over, that's what happens.
>> 
>> On Fri, Aug 24, 2012 at 12:40 PM, <toddcory at finestplanet.com> wrote:
>>> 
>>> i am not understanding the 'wisdom' of using non-grid tie inverters in
>>> this application. it is pretty easy to modify the inverters (board change
>>> out) to grid tie models, which would allow the inverter's to transfer the
>>> loads to the grid (internal transfer switch) and 'sleep' until there is an
>>> outage to back up. the only additional use the system would bring to their
>>> bill is re-floating the batteries occasionally.
>>> 
>>> with no renewable input (except silly, yard-art wind gennys), basically
>>> they have an expensive whole-house ups. i wonder what the intention or
>>> original design was supposed to do?
>>> 
>>> 
>>> 
>>> todd
>>> 
>>> 
>>> 
>>> 
>>> 
>>> 
>>> 
>>> 
>>> 
>>> On Friday, August 24, 2012 9:14am, "Jesse Dahl" <dahlsolar at gmail.com>
>>> said:
>>> 
>>> I do not want to take this on!  The wind, from what I have gathered is an
>>> absolute bust.  Just doing a little online research it seems like they are
>>> getting next to nothing from the wind generators.
>>> From my little understanding of the system and reading replies, I would
>>> say they are buying power, losing 30% of it and then powering loads.
>>> This system was installed by a contractor in Duluth, MN.
>>> Jesse
>>> 
>>> Sent from my iPhone
>>> 
>>> On Aug 24, 2012, at 10:31 AM, Kent Osterberg <kent at coveoregon.com> wrote:
>>> 
>>> Two 1-kW wind generators doesn't sound like enough to provide energy for a
>>> household except possibly in the best circumstances. If there isn't much
>>> wind, the system is getting most of it's energy from the grid. The utility
>>> bill would go up even if they were using the same amount of energy in the
>>> house. Batteries are energy losers!
>>> 
>>> What Dave and others have warned about kWh metering issues is also true.
>>> The new digital meters have many capabilities and the default for most of
>>> them is to record energy going in either direction as energy consumed. Since
>>> they are programmable, the same meter can be used to record net energy -
>>> behave like most disk-type meters; ignore energy in one direction - behave
>>> like a detented meter; or record both incoming energy and outgoing energy
>>> separately - a two register meter.
>>> 
>>> Kent Osterberg Blue Mountain Solar, Inc. www.bluemountainsolar.com On
>>> 8/24/2012 6:26 AM, Jesse Dahl wrote:
>>> 
>>> The system only uses grid power to charge batteries, they have two FX3048T
>>> in parallel so I don't think the meter is the issue.
>>> They did send me a picture of the two wind towers, one is 20 feet off the
>>> ground and one is 60 feet off the ground... No wind would be an
>>> understatement.
>>> 
>>> 
>>> Sent from my iPhone
>>> 
>>> On Aug 24, 2012, at 7:43 AM, David Katz <dkatz at aeesolar.com> wrote:
>>> 
>>> Check to see if their meter goes backwards.  Some utility meters actually
>>> charge for power when you are selling.
>>> Or maybe they have no wind and a new big flat screen tv that they leave on
>>> all the time.
>>> David Katz
>>> 
>>> 
>>> ----- Reply message -----
>>> From: "Jesse Dahl" <dahlsolar at gmail.com>
>>> To: "Wrenches" <RE-wrenches at lists.re-wrenches.org>
>>> Subject: [RE-wrenches] Outback with grid charging
>>> Date: Thu, Aug 23, 2012 11:28 pm
>>> 
>>> 
>>> 
>>> Hello,
>>> 
>>> I got a call from a family today about a system they had installed
>>> recently and they think they have a problem.  They claim their electric bill
>>> has just about doubled since the system has been installed due to outback
>>> using the grid to power the loads instead of the battery bank.  They claim
>>> the MATE always shows the system buying the exact amount as any load on the
>>> system draws.   Due to the distance from my shop, I would like to get any
>>> ideas on what could cause this before I drive all the way there.
>>> 
>>> What I know about the system:
>>> 2 - outback inverters, 48v
>>> 2 - whisper 500 wind generators with whisper charge controllers
>>> 16 - MK 12v AGMS (8/inverter)
>>> 
>>> I guessing setting, but if anyone has seen this before, I'd like to narrow
>>> it down before the drive.
>>> 
>>> Thanks eh!
>>> 
>>> Jesse
>>> 
>>> Sent from my iPad!!!
>>> _______________________________________________
>>> 
>>> 
>>> 
>> 
>> 
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