James Cormican's posts

the modules dont care, but to set up a positive ground system properly, every component in the dc side must also be positive ground.  This is not the common way to do things in north america, so lableing would be required to notify qualified personnel that the negative is not the grounded conductor.  You would have the most trouble finding a positive ground inverter.  If it is your intention to set up a properly grounded permanent system, I would steer away from positive grounded anything.  You can do it, but it will make things way more complicated without offering any advantages.

below is a link that is a must for code-compliant installs.  It is in our how to section.

http://shop.altenergystore.com/pdfs/photovoltaic_NEC_code_practices2005.pdf

james - Alt-E staff

check out renewableenergyaccess.com 

look at the jobs and internships sections.

also greenjobs.com

and homepower.com

You may be able to find a situation that works for you.

- james Alt-E staff

great, kyocera are nice modules as well.

MK makes a nice L16 size battery too if you are looking.

good luck with the system.

james - Alt-E staff

yes, you can do what you are trying to do relatively simply.

1 hp = about 750 watts, so 1/3hp = 250 watts

the next question is how long do you need to run your pump in hours?  take that answer and multiply it by 250.  that will give you the amount of watt-hours your battery must have in storage.  If you dont want to kill the battery every time you need to use the pump in a power outage, multiply the previous watt-hours number by 2 so as to only discharge said battery to 50% and not kill it.

A small module should be able to trickle charge a battery bank that is only used in emergency situations very easily.    This just means that after an emergency, the module will take a long time (several days) to recharge the battery bank.  This setup can be done without solar at all.  you can use your house power and an ac charger to make sure the battery is charged for emergencies. 

regarding the question of "Is a 12v battery enough to power my pump" the answer is - it depends.

this is like asking if 5 people can fit in a car.  if you have a corvette, then no.  If you have a ford taurus, then yes.  There are many sizes of 12v batteries.  They vary widely in amp-hour storage capacity.  It may be that you need 1 big 12v battery or a few medium ones in parallel or perhaps 2 6v batteries in series makes more sense.  It all depends on the watt-hours number you come up from your calculations above.

your system will likely take one of these two routes.

1. ac charger - battery(s) - inverter - pumps

2.pv module - charge controller - battery - inverter - pumps

hope that helps,

james - Alt-E staff

18 volters can be tricky depending what nominal voltage you are running.  For a 24v system you will need two in series, and for 48v nominal you will need 3 in series. 

As long as you select a solid name brand module that is UL listed, you should be fine.  Select one that fits the needs of your location (heat, shading, space, . . .).

james - Alt-E staff

If you are already checking forums for answers, outback has a good forum with lots of tech stuff on their site.  I scan it from time to time. 

james -Alt-E staff

sounds good to me, except that the evergreen cedar series 94-120 have been discontinued.  If that is what you want, order sooner than later, as everybody's quantities are running low.  Also keep in mind that for future expansion on your mx 60, you want to have an array of like modules, so choosing a discontinued module may not be the best choice if slow expansion is in the plans.

- james Alt-E staff

I think the controller will not shut off pump many times depending on intermittent cloud cover.  As long as it is turning it on during the day and shutting it off at night, it is probably working okay.

If you have a two tank system, a temperature gauge between the solar tank and the normal hot water tank will tell you just what the solar has done for you.

maybe some solar thermal folks will come out of the woodwork and throw in their two cents.

- james

and cost about $600,000 for what its worth.

- james Alt-E staff

Off grid is great, but if you are not ready to make the sacrifices to do it, it can be a rude awakening.  Unless there is a large budget ready, if you would use over 500kwh per month, being off grid may be unrealistic. 

On the other hand, some people insist on being off grid.  Instead of huge sums of money spent on solar and wind, they put modest hunks into a big generator and renewable energy sources and batteries.

This question comes up often and the key is to make sure that this is something you want to do and are committed to.  It is a lifestyle change.  Many folks do not have the time or the patience to make the changes necessary to live off grid.  Grid-tie which can be out of sight and out of mind is a great fit for those folks.  For those who know what they are getting into and are stoked to do it, living off grid can be very rewarding.

I bet some folks on the forum have opinions, hopefully we hear from off grid folks.

 james -Alt-E staff

Ken is right on the money.  I always preach to consult with your local AHJ (code-speak for authority having juridiction) which is usually an inspector.  Getting them involved early will make sure that there are no surprises to them or to you.  I usually make sure they have a copy of the spec sheet and owners manual for the inverter as well as for the disconnects, pv modules, and combiner boxes if used.  Then I try to use this document below to make sure the project meets code and present a copy to the inspector if they would like one as well.

http://shop.altenergystore.com/pdfs/photovoltaic_NEC_code_practices2005.pdf

John Wiles does tons of education for inspectors and gives training seminars.  He serves on the board that writes article 690, so the government document above along with him directly as a resource are priceless.

pretty much all of the options you laid out can be done correctly.  I tend to prefer to have the disconnects and inverter on the house. 

what really interested me is where you are going to come up with another 14 siemens 75w modules?  It would be a wild goose chase to find the shell sq 75/80/85 modules which replaced the siemens.  Especially now since solarworld AG bought shell.

james -Alt-E staff

Great,

What does ABYC stand for?

It should be noted that currently all phocos controllers are positive ground units, for those shopping for vehicle/boat applications where that may cause trouble.

They will be coming out with standard US spec negative ground units in 2007.  We'll keep you posted.

-james  -Alt-E staff

or you guys can always reach me at extension 107, at least while I am in the office.

when you are in the community tab, the search feature on top searches the community section including the forum.  I'm not sure if the gallery is included yet or not. 

I typed in "feedback" and found this thread to be fifth on the list.  the tabs can be confusing to some, but they are hadny once you are used to them.  if you click back to the store tab, the search function will go back to searching the store.

 james - Alt-E staff

well, to answer the question, that is 6.7amperes.

I thought it was for a 12v system no?  I'm afraid I'm not aware of a 90v generator that will go unregulated into a 12v battery bank.

Maybe some folks who know more than me about wind can help identify your turbine or how to set it up.

- james Alt-E staff

rock!

thank you ken.  i learned something new today.  I did not realize 12v battery chargers were available for AA batteries.

camera store you say, eh?  hmm, maybe I'll switch my discman bats to 12v recharge mode instead of 120vac recharge mode in the future.

james Alt-E staff

hi,

this is the charge controller global solar wants you to use.  it isn't listed with the rest of the gang because of the sae connectors that are useless to everyone else.  in order to find it you could have searched by brand under "global solar" in the store section.

http://store.altenergystore.com/Global-Solar/m30/Solar-Electric-Panels/Foldable-Solar-Panels/Global-Solar-Cigs-Technology/Accessories-for-Global-Solar-Products/Global-Solar-7-amp-Charge-controller-for-P3/p559/

now as far as the AA batteries, that may be tricky.  I believe brian was working on this for you from an earlier email. let me know if i can help more on that.

the charge controller is designed to regualate charging input and prevent reverse current from FLA, AGM, and GEL batteries.

-james Alt-E staff

I am not sure regarding the sleep mode, maybe some other folks in the community will know.  If you have a mate, check the manual for those settings.

If you can stand the nuisance, I would first shut off ac breaker, then the dc disconnect so that the inverter is off.  Use Dc lighting for middle of the night things and that will save about 50 watt-hours per day. 

how is it living in a yurt, I've never been?

james - Alt-E staff

Well, in theory, that should work.  I have not personally used the huntington resistors.  The other problem I saw is that you said that you were using a C35.  600 watts / 12 volts = 50 amps.  The C35 may not like that.  I would check with the turbine manufacturer to see what they suggest as a setup to be safe.

-james Alt-E staff

Well Jeff,

You are likely to get a few different opinions on this one.

First off, it is important to know that any grid tie inverter that has the appropriate UL approvals is  safe and probably of good quality.

Now as far as preferences, everyone has their own.  In the office, I tend to be the driver of the sma band-wagen.  SMA was very good to my alma mater, San Juan College.  For a Mass rebate system, a Solectria inverter is very attractive because they are made in massachusetts.  Fronius does have the most data monoriting options, but SMA and PV powered have nice data monitoring options as well.

feel free to call or email me directly and I can send you a quote. 
my address is my first name at altenergystore.com

for the rest of the forum folks, if there is interest in grid tie package deals, let me know and we can put some up as examples.

 james Alt-E staff

Usually these would be connected at opposite diagonal ends of the battery bank.  If you have a number of inputs, you may want to use a power distribution block, busbar, or insulated terminal block to minimize connections to battery posts.

It is unlikely that the modules will be able to equalize the bank, but I am not sure what your charge controller does, or how the other controllers will react. 

There is usually no problem putting separate controllers in parallel on a battery bank.  Sometimes they fight with each other, so just keep an eye on it after the install if you have any monitoring devices.

Some other folks on the forum may have some ideas as well.

james -  Alt-E staff 

dump load resistors, my friend.

check these out.

http://store.altenergystore.com/FusesBreakersEtc/Dump-Loads-Dump-Load-Controllers/Diversion-LoadsDump-Loads/c516/

if you dont have a water heater that you can use, you can use the air resistors.  I have also heard of people getting a small electric rv water heater and switching to those dump load resistors and having it feed into their regular water heater.

If you get the air resistors, you will have to get a suitable box for them (usually metal with grates).  We have not found a good commercially available one yet, otherwise we would sell it.

james - Alt-E staff

well, how about here? haha

It really depends on what type of light, where you are, how many days of autonomy you need, budget, area for solar without shade, etc.

Unfortunately, it is usually as not as easy as people think.  there is no magic box that I could send you that has all the bits and cool instruction manual that is one size fits all.  There is some design involved, everything is custom.

check out home power 93 page 86.  I always harp on this article, but it is great for a reference on what you are getting into as well as great example system to follow.

feel free to call if you have any questions
good luck,

james - Alt-E staff

more details, what modules do you have?  what is your battery bank voltage and inverter?  where are you located geographically (for temperature deration)?

odds are the answer will be an MX60 to run at higher voltage.    A combiner box at the array, and that way you only have to run two large wires rather than multiple medium wires.

I'll be glad to help design your system, I just need some more info

- james - Alt-E staff

I get it now.  That could be tough to pin down because the new buyers may not care at all about sustainability or the like.  Real factors would include years remaining on factory power output warranty, daily energy production, daily energy production vs. cost of energy offset, cost of removal (like you said), anticipated payback, etc.

Also, it may be interesting to find out if government rebates or tax credits apply when buying renewable energy products used.  for a system this large, the green tags may be worth a lot as well.

james - Alt-E staff

yep, outback sealed inverters (fx series) no "v" in front for vented. 



or xantrex marine units like the freedom marine series.

outback sealed units include

fx2012t - http://store.altenergystore.com/Inverters/Off-Grid-No-Utility-Needs-Batteries/2000-to-2999-Watts/Outback-2000W-FX2012T-12VDC120VAC-Inverter/p843/

fx2524t - http://store.altenergystore.com/Inverters/Off-Grid-No-Utility-Needs-Batteries/2000-to-2999-Watts/Outback-2500W-FX2524T-24VDC-Inverter/p848/

fx3048t - http://store.altenergystore.com/Inverters/Off-Grid-No-Utility-Needs-Batteries/3000-to-5500-Watts/Outback-3000W-FX3048T-48VDC120VAC-Inverter/p849/

m for mobile

fx2012mt, fx2524mt, fx2532mt - available upon request

or xantrex freedom marine series

http://store.altenergystore.com/Inverters/Marine-Inverters/100-to-2000-Watts/c589/

and

http://store.altenergystore.com/Inverters/Marine-Inverters/Above-2000-Watts/c590/

check those out, let us know if you have any questions.

-james - Alt-E staff

  Evergreen Modules are great, but they have a couple things that will not make them ideal for a sailboat.  first, they have no specific marine rating, unlike a kyocera.  Second they do not tolerate shading very well, unlike a unisolar. 

For sailboat situations, we usually suggest a kyocera or a unisolar.  Many have used evergreen modules on sailboats with no problems, the choice is yours.

Regarding the controller, it is important to know that it is a positive ground unit.  Here in the united states, the negative is usally the grounded conducter.  Especially on boats and RVs , positive ground can cause problems if grounding is necessary.

from phocos manual - "Be aware that the positive terminals of the CX controller are connected internally and therefore have the same electrical potential.  If any grounding is required, always do this on the positive wires."

"Remark - If the CX is used in a vehicle which has the battery negative on the chassis, loads and solar panels connected to the regulator must not have an electric connection to the car body.  Otherwise the overcharge protection, the low voltage disconnect and the electronic fuse function of the controller is short-circuited."

You should move the controller away from the modules to get them out of the outside environment; 2 meters is fine, move it farther if you need to as long as wire is sized correctly.  Lastly, you may want disconnects between your solar and controller and controller and battery(s).  Inexpensive solutions could run about $60.

- james - Alt-E staff

 

Well, taking things apart is usually easier than putting things together.  That is a HUGE job, you would likely have to call a pretty large solar contractor or maybe just an electrical contractor to get appropriate bids.

I just have to know why a system that large needs to be un-installed.


james - Alt-E staff

you will have to do your own research, but I know these companies are publically traded.

Evergreen Solar - nasdaq - ESLR

SunTech - NYSE, I think, don't know ticker

BP - dont know their info

I know for sure that there are some "green" funds that deal with renewable and sustainable companies.  If anybody else has info on other companies or funds, go ahead and post.

- james Alt-E staff

what type of differential temp controller are you using? 
at worst case the controller may have failed.  if you replaced the controller and the sensors, that would probably cost around $200.  You can buy the sensors and try that first, they cost around $20.

here is a link

http://store.altenergystore.com/Solar-Hot-Water/Accessories-DIFFERENTIAL-TEMP-CONTROLS/Sensor-Ddt-Diff-Temp-Ctrols/p2400/

james - Alt-E staff