Off grid system recommendations

mattg
mattg Registered Users Posts: 17 ✭✭
Hi, this is my first post to this forum (I'm also posting it on a few of the larger similar forums) - I'm somewhat new to all this, but I've been doing a lot of research into off grid power setups for the last couple of months, since purchasing a piece of land in New Zealand. My family of four will be moving there from here in the US in 6 - 18 months from now, we'll start building our house shortly after we arrive.

I've been quoted $20,000 to run grid power to the site we'll be building on. I've always wanted to get off the grid as much as possible, so it was a no-brainer to decide not to pay that kind of money to be grid tied!

Seems to me the site is ideal for off grid power - the land is mostly on a north facing side of a hill (Southern Hemisphere, so north facing being best). I have a stream on one boundary, that should give me about 30 feet of head with good enough flow in summer to give me .5 to 1kW (rough estimate). And I have an elevated spot above the building site that would seem to be good place to put a small wind turbine.

Researching the New Zealand prices of the gear I'm looking at purchasing, it didn't take long to see that I'd be much better off sourcing a lot of it here in the US before leaving. We'll be shipping our gear over in a 40 foot container which will have some room to spare, so it's not going to add to the cost of the move.

I have a preliminary list of what I'm planning to purchase, based on a combination of my research and various recommendations I've received. As I have no practical experience, I can see there is a high possibility of making some wrong choices here. So I'd be grateful for any guidance anyone can offer on this proposal, or different approaches, as there are no doubt many oversights I've made:

For panels, I'm looking getting a pallet of 25 Astronergy 255 watt panels. The house we are looking at building is fairly small, but the north facing roof is the perfect size for 24 panels, getting a pallet means I'll have one for a spare. I figure that even though maybe that's a lot of panels, they will help on cloudy days to meet our needs.

For charge controllers for the PV, looks like Midnite Classic's are the way to go. I'm told for that number of panels the best configuration is going to be two Classic 150s, each with 12 panels wired with 4 parallel sets of 3 in series.

Batteries: I like the idea of getting sealed AGMs to avoid maintenance. I've found what seem to be good prices on Rolls Surrette S6-460 sealed AGMs, advertised as 6 volts 415 ah. I'm looking at getting 8 of them for series connection to get a 48 volt bank. If I buy them now (good price and free shipping as part of a package), and make sure I top them up once a month or so with a trickle charger, before using them in the system for a year or so, will they be compromised at all?)

Inverters: I've been recommended Outback, Magnum and Schneider, they all seem to have their pros and cons. As it seems there are more Outback inverters in use in use in New Zealand than the others that I've been recommended, I'm leaning towards the 3.0kW, 48V Outback VFX3048E (the 230V 50 version). I think we could mostly get away with a 3kW inverter if we change our power usage habits accordingly. But I'd like to know I can have a few higher demand appliances running at once without wondering if everything is going to fall over during periods of high demand, so I think I'll get a pair of them running in parallel. I also like the idea of adding redundancy in case one of the inverters fails, I'll at least be able to keep things running with one inverter.

(I'd like to figure out how I can get the second one to sleep as a slave to the primary master, and only kick in when required - I think this is possible. I will phone Outback tech support on Monday. Not sure if this can be configured in such a way that if the master fails, the slave automatically takes over - that would be great).

I think running two or more FX inverters requires a Hub4, and I'd also get a Mate2 for setup/monitoring.

For mounting the inverters, breakers, etc, I initially looked at the Midnite ePanels which I like, but as I'm probably going with Outback for the inverters, if I go that way I think a Flexware 500 enclosure may be a better option.

I don't want to spend too much on a wind turbine, as I'm not sure about my site. I figure if I got a 48V Primus Air 40, and a 45 foot pole kit - that would be a fairly low risk investment, it directly connects to the battery bank and doesn’t use a charge controller, diversion loads etc. I'm not sure how much it would contribute to my production, but it will be interesting to find out.

For a water turbine, the Powerspout looks like a nice piece of gear. It's made in New Zealand so if I go that route, it will be purchased over there.

I was going to use a Midnite Kid for the charge controller for the micro hydro (as it allows a diversion load to be directly connected, as I understand it, and lets you divert the voltage directly from the hydro to the dump load, meaning you can use 115 volt water heater elements). But I was told by Midnite the other day that hydro support for the Kid is now discontinued.

So it looks like another Classic 150 is the way to go here - I could get something less expensive, but seeing as I would already have two for PV, I like the idea of having shared components in the system that I can swap in and out if case of failure. This means I'd require some solid state relays (suggestions?) to control with the Aux2 output of the classic, as I want to use 48 volt water heating elements for my diversion load. This way, I could potentially be heating my water for much of the day in summer once my battery bank is back up to float once the previous day's usage is replaced.

Seeing as I'll have three Classics, I'm thinking I could add a second water heater element for redundancy. The primary element could be set to divert at one threshold voltage on one Classic, and the redundant one could be set to divert at a threshold voltage set to be a fraction higher on one of the other Classics.

The three classics, as I understand it, will let me connect three Whizbang Jrs and shunts, one per Classic on Aux1. If it makes sense, I'd like to add extra shunts/Whizbangs around the system, and switch them in and out manually to monitor currents at different locations (engineer nerd side of brain speaking now). I've asked Midnite what they’d recommend, they are going to have someone call me back.

Someone recommended the Outback FN-DC monitor system, but as the Midnite Classics already come with Whizbangs, and both setups require shunts, I figure I'd get pretty much the same results with the Midnite solution, without the extra expense of the Outback parts? Seems there are more options monitoring remotely when using a Midnite setup.

I'd think the lighting for the house should be LEDs run directly off the 48V battery bank. Not a lot of choice though for that voltage...so maybe a step down transformer to 24V would be the best option. Not sure yet if we should purchase 48v refrigerator/freezer to allow the inverters to be off for longer at night.

I realize that for a system of this size in terms of PV and inverter power output, a larger battery bank may be recommended. With this project I’m mindful of keeping the costs down where possible, without compromising reliability. I'm willing to buy once/cry once, and get a long lasting reliable system that does not end up being overly restrictive. But trying not to use the funds I have unwisely.

I just don't like the idea of tying any more money than is necessary up in batteries just yet, seeing as they seem to be the parts that will be most likely to need replacing, sooner rather than later, compared with the other components in the system. And perhaps the most prone to failure. The bank I'm looking at is $4200, the next step up for a 48V setup seems it has to be double that - not sure I'd be able to swing it just yet, but, I'd like to potentially expand it in future.

I'm hoping that 415 A/h at 48V, nearly 20kW of battery power, may turn out to be enough for now, if we make a few changes to our power consumption habits, e.g. performing most of our power intensive activities during the day when the PV is producing. And not use more than 10% of the battery capacity per day, for up to 3 days, while the PV is not producing, in order to prolong the life of the batteries (of course I'm counting on the combination of wind and hydro to be able to make that happen).

I'm planning on having the system assembled for me, and I'm being recommended the following (with much or all of this going in the Outback Flexware FW500-AC system I guess) - 8 Midnite 15A DC DIN breakers, 2 Midnite MNSPD300 surge suppressors, 2 Outback Flexware FW-DCA DC adapters, 2 Midnite MNEDC-175 DC panel mount breakers, 1 Outback FW-IOB-D-230VAC dual inverter input-output-bypass, 2 Outback Flexware FW-SP-ACA AC adapter w/surge suppressors, 4 Midnite DC panel mount 3/4" MNEDC-100 amp 150VDC breakers, 2 Midnite DC panel mount 3/4" MNEDC-100 amp 150VDC breakers. And a couple of MidNite MNPV-6 6 position combiner boxes. And all the necessary wiring.

I’ve just started looking at generators. Seems I can avoid extra components if I use a generator with 2 wire start (can be controlled from the Outbacks). I like the idea of a diesel because I’ll be experimenting with biodiesel for my vehicles (canola oil cut with gasoline), so the fuel could be shared. And I’d want something fairly small and inexpensive, just for kicking in when/if the batteries get discharged more than 30% or something like that. Any suggestions? If the costs of using a small diesel generator started getting to high, I’d be open to gasoline (but not propane). Might be best to pick this up when I’m over there.

The total cost (apart from the charging generator, and hydro generator / associated piping) comes in about $22k.

About what it would cost to get on-grid :-)

Comments

  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: Off grid system recommendations

    We've seen a rash of problem with Rolls lately, not sure if I would want to be so far away if you have problems. Any battery sources in New Zealand?

    That is a pretty minimal battery bank for a family, you might have some issues, I know you can't have a firm grip on loads, but do you intend to have A/C? Well pump? Elec. Water heater?

    The other important thing to know is your solar isolation? How does the weather work out with the potential, hydro? rainy season the hydro helps make up?

    We largely discount small wind, seems to often be more trouble than it's worth... I have no direct experience though.

    I think the Classics only work with one whiz bang if your going to use 'follow me' to monitor the power gong into and out of the battery bank, follow me will integrate the classics into a charging system rather than independent chargers, kinda surprised they wouldn't have snaped back that answer, so the boys must have something going on...
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • mattg
    mattg Registered Users Posts: 17 ✭✭
    Re: Off grid system recommendations

    Thanks Photowit,

    There are battery sources there, but they are relatively pricey...I've heard good things about the Concorde Sun Xtender batteries, I plan to check them out also.

    Won't be having A/C, will use a ram pump for water, and only excess power will be used as a secondary way to heat water. Larger loads will be refrigerator, freezer, washing machine, dishwasher, microwave, vacuum, computers, power tools.

    By solar isolation do you mean info like this, which I downloaded for my specific build site?

    Attachment not found.

    Water levels for the stream I'll be using for the hydro definitely pick up in winter, but I'm not sure how much. The stream doesn't freeze over fortunately. Wind picks up a lot more during the winter when it's needed.
  • petertearai
    petertearai Solar Expert Posts: 471 ✭✭✭✭
    Re: Off grid system recommendations

    Dont waste your time with wind. Stick to pv and hydro . Consider mounting panels on a stand rather than on your roof , this is easier for water tight and cleaning and so on. . Inveter samsung fridge freezers are a reasonable price in nz , and energy efficient. so stick to 230 volts ac for your refrigeration. Also i personally would do lighting in 230 volt led as these are getting more efficient and cost effective. You will need to use a registered electrician to set up what you need, they will need suppliers documents for all equipment that is installed . MAKE SURE this can be achieved with the gear you intend to import yourself. Other wize your savings on the stuff you bring in yourself may end up being a cost. All the best with your new adventure .
    2225 wattts pv . Outback 2kw  fxr pure sine inverter . fm80 charge controller . Mate 3. victron battery monitor . 24 volts  in 2 volt Shoto lead carbon extreme batterys. off grid  holiday home 
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Off grid system recommendations

    You might want to talk to user zoneblue http://forum.solar-electric.com/member.php?11848-zoneblue who lives in New Zealand and recently important some stuff as you are thinking of doing: http://forum.solar-electric.com/showthread.php?24118-Importing-inverters

    He could probably help you a lot.
  • mattg
    mattg Registered Users Posts: 17 ✭✭
    Re: Off grid system recommendations

    Hi Cariboocoot, just checked out Zoneblue's site and he looks to be doing very much what we are looking at. THANKS!!!
  • mattg
    mattg Registered Users Posts: 17 ✭✭
    Re: Off grid system recommendations

    Hi petertearai, thanks for the advice! Good call re: off-roof mounting, I think I'll go that route. 230V fridge and lighting would simplify things for sure, will look into that. So the entire system from PV to inverter for a 100% off grid setup just needs to be signed off by an RE, or do they need to install everything? I was hoping that if all the components checked out OK, a pre-wired setup would be OK to use...I'll get in contact with NZ solar installer, thanks for the heads up.
  • AuricTech
    AuricTech Solar Expert Posts: 140 ✭✭
    Re: Off grid system recommendations
    mattg wrote: »
    I’ve just started looking at generators. Seems I can avoid extra components if I use a generator with 2 wire start (can be controlled from the Outbacks). I like the idea of a diesel because I’ll be experimenting with biodiesel for my vehicles (canola oil cut with gasoline), so the fuel could be shared. And I’d want something fairly small and inexpensive, just for kicking in when/if the batteries get discharged more than 30% or something like that. Any suggestions? If the costs of using a small diesel generator started getting to high, I’d be open to gasoline (but not propane). Might be best to pick this up when I’m over there.

    If you expect to go several months at a time without using your generator, it might be worthwhile at least to look into a propane-fueled generator. That way, you wouldn't have to worry about stale fuel or bulk fuel storage issues. OTOH, if you expect to run your generator at least once a month or so, liquid fuels should be fine.
  • zoneblue
    zoneblue Solar Expert Posts: 1,220 ✭✭✭✭
    Re: Off grid system recommendations

    Hi Matt,

    Nelson has a nice sunny climate, and with your creek, you are good to go!. Id focus on the solar and the hydro, in this country they are a match made in heaven (just wish the nz govt could see it that way [1]). Without seeing your numbers i wouldnt be stressing much about generators or wind at all.

    I know the powerspout guy, he lives just up the road, and his and all the systems around here run without generators. He runs his entire powerspout manufacturing business, a backpackers, a cottage, and his family of four house, 100% off small hydro and solar.

    IMO you are right to be wary of spending big on batterys. For one thing with hydro you dont need as much storage, because even though those things dont put out a huge amount of amps, say compared to solar, they do it 24 hours 7 days a week, which supports your overnite and inclement weather loads on the fly. If you are good with excel you can run the numbers to reassure yourself that it will work.

    The point of matching midnite classics to powerspouts is not the diversion per se, its that with a Classic 200, becasue of the high Voc rating, you dont actually need diversion. Not saying diversion is not needed, just that its something you can do later.

    Batterys, to buying now, nah. 6-18 months is a small lifetime in the realm of a battery. Its about quarter the banks calendar life, and the battery market is rapidly evolving (or trying to), and prices and options can only improve in my opinion. Do look into LiFePo4, its the most promising contender for now.

    Certification. What Michael Lawley does with a lot of his installs, is you do as much of the work as you can/want to do, and he has contacts for RE freindly sparkys that will do the rest, and sign off the installation. But be sure to get them involved early so theres no surprises, ie approve the design as well. Hes a colorful character.

    Importing. Yes distributers here markup stuff a horendous amount. You can expect to get USA made stuff about 35% cheaper by importing it yourself, thats including all freight and duty. Im not exactly sure what the rules are on 'personal effects', youll need to check that one.

    Youve got a bit of time, my advice is to invest it in research. Dont make any hasty purchases, regardless of 'deals'. Thats a typical trap for new players. Ill send you my email, give me a holler any time. But i recomend that you use the forum, the embodied knowledge here is vast, and by running each decision by here for peer review can only result in a happy happy install.

    --
    [1] Large hydro as a percentage of total electric product is declining rapidly, gas is growing, and the only expected renewable growth area is geothermal. See www.med.govt.nz/sectors-industries/energy/energy-modelling/publications/energy-in-new-zealand-2013

    With such a large installed hydro base, NZ, like Canada, and Scandavia could achieve 100% renewable energy almost overnite... if we could get out of our own way.
    1.8kWp CSUN, 10kWh AGM, Midnite Classic 150, Outback VFX3024E,
    http://zoneblue.org/cms/page.php?view=off-grid-solar


  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Off grid system recommendations

    I would NOT buy batteries now, and hope to store & maintain for a year. AGM have shorter lives than flooded, and you are looking at consuming 1/5 of your battery life just sitting.

    Additionally, I'd advise against AGM for a first bank, they are un-forgiving if overcharged (possible if you have hydro 24/7 and are tuning your dump loads)

    Also, be sure that the gear your buy stateside, is electrically compatible with the NZ grid. All the appliances there, generators..... need to match. And if your site ever did get grid.....

    20K for the grid vs 22K for RE + new battery bank every 7 years. Grid power with a GT load shaving system is worth consideration.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • stephendv
    stephendv Solar Expert Posts: 1,571 ✭✭
    Re: Off grid system recommendations
    mattg wrote: »
    I have a stream on one boundary, that should give me about 30 feet of head with good enough flow in summer to give me .5 to 1kW (rough estimate).

    This is GOLD. If you've done the calcs right then 500W x 24 hours = 12kWh per day which should be more than enough to run your entire home all on its own (excluding space heating).
  • petertearai
    petertearai Solar Expert Posts: 471 ✭✭✭✭
    Re: Off grid system recommendations

    In newzealand the install is governed by standards newzealand. It is a joint set up with Australia. Requirements for pv arrays is AS/NZS 5033: 2012. Standard for Standalone power systems is AS/4509 . You can buy them on line from standards newzealand. The whole thing needs to be certified by a registered electrician . It will also need to be inspected by a registered inspector. Zone blue is right to advise early involvement of your electrician, his licence is on the line for the install , so while you can do lots of the donky work he has to be involved early. there is a nz forum predominantly used by sparkies called electrical forum , this may be of some use, there are a few threads on pv power. ( be warned it is a bit more robust than wind sun but still there are some very knowledgeable people on it ).
    wind sun is a fantastic site , you will certainly find the people here great . o and another nz site ecobob may be of some help to ask questions, although not a big number of followers there. Dont be too worried about flooded lead acid batts , they are not difficult to maintain , and easier to monitor than sealed batts .Regards Peter
    2225 wattts pv . Outback 2kw  fxr pure sine inverter . fm80 charge controller . Mate 3. victron battery monitor . 24 volts  in 2 volt Shoto lead carbon extreme batterys. off grid  holiday home 
  • zoneblue
    zoneblue Solar Expert Posts: 1,220 ✭✭✭✭
    Re: Off grid system recommendations

    On the customs situation for returning citizens, this appears to the deal:
    Duty-free entry for household items
    
    ​When entering New Zealand either as a returning citizen or resident, or if settling for the first time, your household or other related effects will be admitted free of Customs duty and goods and services tax (GST) for a reasonable time after you arrive, provided you can meet the following requirements:
    
     -   You have arrived in New Zealand and, on the date the effects are imported, hold a document authorising residence in New Zealand.
     -  For the whole of the period of 21 months preceding your arrival, you have lived outside New Zealand (brief holiday or exploratory visits do not exclude a person from qualifying for this concession).
     -  You have owned and used the goods before the date of your arrival in New Zealand.
     -  The goods are for your own personal use and are not intended for any other person or persons, or for gift, sale, or exchange.
    
    Exceptions
    
    The following goods will not qualify for duty-free entry, unless you can establish that they were for your own personal use prior to their arrival in New Zealand:
    
      -  Any goods shipped directly after purchase to avoid local taxes in the country of export.
      -  Replacement electrical equipment operating to New Zealand standards.
      -  Goods of a commercial nature (such as factory plant and office equipment). 
    
    In these cases you may need to pay Customs duty and any other applicable charges.
    

    http://www.customs.govt.nz/features/charges/dutyfree/Pages/default.aspx

    Technically those last clauses target the likes of what you envisage. But i imagine theres a fair bit of wiggle room there. I would be inclined to talk to some people who have actually done it, to find out how they process this in practice.
    1.8kWp CSUN, 10kWh AGM, Midnite Classic 150, Outback VFX3024E,
    http://zoneblue.org/cms/page.php?view=off-grid-solar


  • mattg
    mattg Registered Users Posts: 17 ✭✭
    Re: Off grid system recommendations

    Been away from anywhere with internet access for a couple of weeks, just checked this thread again - thanks everyone for all the advice! I have a whole lot more to think about now...