Announcement

Collapse
No announcement yet.

need a quick update on whats available

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • need a quick update on whats available

    I looked into this a while back, as I was starting to build a house, but than I dropped it, now I am at a point I could use some power and while utilities are available at least for now I would rather not hook up.

    right now all I need is to run some power tools while I build the house, I came across some Suniva panels locally for a decent price I have a battery supplier that has some deals too, ordered a pwm charge controller the idea is to hook up a 24v system and run some cordless tools off it, but rather chop up an extension cord and run the tools as plugged in to the battery bank.

    so I gone into pvwatts while waiting for my account to be validated and a 2 kw array on a tracking rack makes plenty for my needs 8 months out of the year, I always wanted a couple windmills to go with it, but than I read how for the most part you all disagree with off grid systems where utilities are available.

    I spent some time reading into this but not for the past couple years, can some of you get me up to date as far as what components are to be had these days?

    the current home I live in I have been tracking my consumption over the years, I average about 300 kwh/month, last month was 8.4kwh/day, I've seen upwards of 12 kwh/day, I am hoping to reduce that some more in the new home, I am currently running an old fridge etc.

    so what am I in for besides panels and batteries? have any of you tried running a DC fridge? that is my largest hog? that being said, I am still looking into what voltage system to settle for, I see components up to 48 volts, wonder if any dc appliances are available what are they wired for?

    I was looking into maybe run some of the appliances right off the battery bank, save some wear on an inverter or even use a smaller one, maybe even change my ways and do laundry during peak production hours, run the fridge on a similar manner, save the batteries a few charge discharge cycles, and so on

    any tips much appreciated, I am looking for specifics:
    recommended system voltage,
    recommended inverter ( saw one that was a split phase 240v ac, I believe this is similar to residential power? 2x 110v lines? )
    energy conscious appliances ( fridge, Washer, what else I may need.. )

    Thank you
    Last edited by georgerc; 04-24-2017, 12:13 AM.

  • #2
    for what this may be worth, I understand I may be better off plugging into the grid, or that a pwm controller is inadequate, this is just something I am setting up temporarily to run some power tools.

    I could also use some help with other miscellaneous products, for example I came across some battery terminals with built in fuses, where do you get your hardware connectors and such from?

    Comment


    • #3
      beware plugging cordless tool chargers into ModSine wave inverters, the modsine may fry the charger, keep an eye on the temp of the charger parts and don't use modsine if they start heating up a lot.
      Powerfab top of pole PV mount (2) | 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

      Comment


      • #4
        +1 here.

        I ruined all my Makita cordless batteries using a modified sine wave inverter. They aren't cheap to replace.
        2.2kw Suntech mono, Classic 200, NEW Trace SW4024

        Comment


        • #5
          If you need temporary power for construction you would be better off getting a 2000watt inverter type generator. It will be cheaper then a solar / battery system and provide much more power especially when the sun isn't shining.

          Comment


          • #6
            ok so let me clarify this a bit, the long opening thread may have been confusing,

            I have utilities on site I could just have temporary service, or heck run it right to the house, and install a load center, RE is something I want and I figured this would be a good way to start see how it works out.

            so far I picked up 4 Suniva 235w panels, and a couple batteries, I tried them out today and wired an 18v cordless drill/circular saw, right into the battery bank, no inverter and such, I am running DC tools, straight up.

            that being said it worked but not enough power, the tools are Harbor freight and they were crap right out the box to begin with, so I blame it on them, for the most part, the other issue might be the crappy extension chord I used, some old 16 ga, may not be able to carry enough amps, thing is I looked at the tools and I couldn't figure out what kind of amps they require, I believe the original packs are made up of 2ah Nimh, shoothow much could they pull to begin with a 2C maybe, it was an educated guess .

            so here's where I am at, either stick with the 24v and get some better cordless tools, or go higher

            still haven't heard from you guys some input on what a system voltage I should settle for in the end, so far looking at available gear, looks like 48v is about as high as it is commercially available.

            that being said, looks like todays cordless tools are about 20-24v, except for dewalt flex votl at 60v, so I got to thinking how do I go about this?

            if I step up to a 48v system, it may not run those tools, if I go 72 that may be too much.

            theoretically speaking, I read the main complaint with a pwm controller is the charging voltage is too low for the panels output.

            mine today were putting out 34v oc, 2 in series would be 68v, normally you would hook this up to a 4s battery bank for a 48v system, so.... suppose I hooked them up to a 5s battery bank for a 60v total? could this work, the bank would be closer to the panels OV, possibly more efficient charging, and I could get some 60v flex dewalt tools and run them as chorded tools plugged into the 5s- 60v bank

            again just speculating, I'm sure the 60v charge controller would be a challenge and so on, but what is your input?

            the other thing the 4panels x 24v comes up to 96v, most 110v ac corded tools use universal motors, pretty sure they would run just fine on 96v DC, id need 8 batteries and it be interesting how to go about a charge controller but just another thought


            that being said, aside from the current project, ultimately I'd like to get a small powerplant going, considering I plan on wind and solar combo, I seem to have read at some point of 144v setups, my panels advertise a 600v max system, but I am not familiar with what's available these days, what is a good setup to look into, 48v?, are there components available for higher voltage setups? it gets expensive?

            I tried looking into it briefly and the selection is overwhelming, if you guys are partial to a certain system voltage I'd like to know what is it and why you chose it and what componnents would you use ( ex charge controller, inverter etc

            keep in mind I use about say 10kwh/day on average,

            thank you

            Comment


            • #7
              Now I am confused. Are you building a solar / battery system for your home or to run your power tools?

              As far as I understand you will need 115V AC power to run the chargers that work with your power tools so what does the battery voltage have to do with your tools?

              For a large battery system it would be best to go with a 48volt system. But if you have grid power then why are you even thinking about batteries. You will never get your money back using a battery to generate power.

              If you want to go with solar then install a grid tie system with high wattage panels and a legal grid tie inverter.

              Comment


              • #8
                No, no, no... your panel is actually to low in voltage to use in two in series on a 48 V bank. I'm guessing yours is really closer to 37 Voc, typical ratings are below. You need to operate at Vmp to get maximum power out of the panel.

                12 V panel = 22.5 Voc, 17.8 Vmp
                20 V panel = 37.5 Voc, 30.5 Vmp
                24 V panel = 45.5 Voc, 37.0 Vmp

                The problem is that a 24 V bank needs to be charged up to about 28.8 V, or a 48 V bank needs to be charged up to 57.6 V (higher if you want to run Eq cycles). Two 20 V panels in series appears to give 61 Vmp, but once you account for temperature, the voltage could drop 10% and be lower than where the battery needs to be and you can't fully charge.

                If you use a 150 V mppt controller, you can put all four 20 V panels in series and have efficient charging for a 48 V bank.

                If you use a PWM controller, the panel operating voltage is determined by the battery (not the panel's maximum operating point), which costs you efficiency.
                CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

                Comment


                • #9
                  If you have utilities on site then considering a stand-alone type PV system (as if you were off grid) is wasting both your time and money. Build your house and play with RE later after you understand what you need and what it costs to maintain.
                  Dave W. Gilbert AZ
                  6.63kW grid-tie owner

                  Comment


                  • #10
                    Call the POCO and get a Construction Power Pole Installed. Much less expensive and actually works day and night.. .
                    MSEE, PE

                    Comment


                    • #11
                      OK so let's clarify this a bit
                      First off I am not hooking up a stand alone system to run an inverter to charge my power tool batteries, instead I ran a chord from the 2s battery bank, 24v straight into the power tool, where it's battery would normally plug in

                      Second I have 4 pannels and I can get more so I can configure them in n several ways just trying to decide which, as it sits right now o have 24 v panels in parallel to a 2s battery, I was exploring the idea of rewiring them for 48 v but there are no power tools running at that voltages

                      Third I am well aware I can get temporary service from the poco, a generator or at some point grid tie them, I have not explored the grid tie setups and yet,

                      This is something I want to mess with because I can, I understand a grid tie would be more cost effective, I'll look into that after the house is built, I have plenty of other permits and inspections to deal with till than

                      thx to senij, I thought those were 24v pannels, they are suniva 135 w , I believe 60 cells? For whatever reason I thought a 12 v panel is 18 voc therefore these may be 24voc

                      Tell me more about that charge controller a quick Google search yealded up to 48 v have yet to come across a 150 v controller, my 4 panels would add up to 80 v guess anything below 150 would work? I can get a few more pannels if that's the case just as I mentioned I am not ffamiliar with what's out there, so far were talking system voltage and charge controllers

                      Comment


                      • #12
                        Originally posted by georgerc View Post

                        thx to senij, I thought those were 24v pannels, they are suniva 135 w , I believe 60 cells? For whatever reason I thought a 12 v panel is 18 voc therefore these may be 24voc

                        Tell me more about that charge controller a quick Google search yealded up to 48 v have yet to come across a 150 v controller, my 4 panels would add up to 80 v guess anything below 150 would work? I can get a few more pannels if that's the case just as I mentioned I am not ffamiliar with what's out there, so far were talking system voltage and charge controllers
                        Slow down. With an mppt controller, the operating voltage of the array is not the same as the battery voltage. If you have 60 cell panels (these?), they are "20 V" panels, with a Vmp of 30 V. The 150 V limit I was talking about is the Voc limit for some of the better charge controllers, independent of whatever your battery voltage is. You would not be able to put 4 of those panels in series on a standard 150 V controller... the Voc at 25 deg C is already over 148 V, so any colder would exceed the limit. Some Midnight Solar controllers have a "hyper VOC" mode that helps expand the voltage input range.

                        You need the lowest temp-adjusted Vmp that you calculate for your array to exceed the highest charge voltage (equalization voltage, if FLA) that your battery requires.
                        Last edited by sensij; 04-24-2017, 08:13 PM.
                        CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

                        Comment


                        • #13
                          They look a bit different but the specs I pulled up are similar I'll check the tag on them tomorrow, but that be the case these are 20v, i thought they were 24v, vmp is listed at 29.5v i asumed that was plenty to charge 24v

                          so when talking mppt controller you add up voc, guess I have to look at some controllers, I only came across up to 48v guess that was the output, what happens when I want 4 more pannels, don't different string? Bigger controller? What's out there?

                          Comment


                          • #14
                            Originally posted by georgerc View Post
                            OK so let's clarify this a bit
                            First off I am not hooking up a stand alone system to run an inverter to charge my power tool batteries, instead I ran a chord from the 2s battery bank, 24v straight into the power tool, where it's battery would normally plug in

                            Second I have 4 pannels and I can get more so I can configure them in n several ways just trying to decide which, as it sits right now o have 24 v panels in parallel to a 2s battery, I was exploring the idea of rewiring them for 48 v but there are no power tools running at that voltages

                            Third I am well aware I can get temporary service from the poco, a generator or at some point grid tie them, I have not explored the grid tie setups and yet,

                            This is something I want to mess with because I can, I understand a grid tie would be more cost effective, I'll look into that after the house is built, I have plenty of other permits and inspections to deal with till than

                            thx to senij, I thought those were 24v pannels, they are suniva 135 w , I believe 60 cells? For whatever reason I thought a 12 v panel is 18 voc therefore these may be 24voc

                            Tell me more about that charge controller a quick Google search yealded up to 48 v have yet to come across a 150 v controller, my 4 panels would add up to 80 v guess anything below 150 would work? I can get a few more pannels if that's the case just as I mentioned I am not ffamiliar with what's out there, so far were talking system voltage and charge controllers
                            So you want to take the solar panels and charge a 2S battery which you will then wire directly into your power tool. I guess that is something I would have done back in high school when I didn't care about electrical safety or the possibility of destroying my tools.

                            Sounds like you just want to find a use for your solar panels instead of just purchasing a new battery for your power tools.

                            All I can say is don't get hurt or tell anyone else that what you are doing is safe because it is not on so many levels.

                            Comment


                            • #15
                              I'm no stranger to electricity, I've done vorst, for conversation sake let's just assume I've taken the necessary precautions, but 24 v is 24 v doesn't matter if it's lithium or led, if anything I may have some issues with transmission losses. For the record I have bteries for those tools just trying to keep it simple, why go from 24 DC through an inverter , back to 24 DC just to run out of battery a few cuts later, or that's the idea at leas.

                              That being said, now that I realise these are 20v panels and at least in theory that's not enough juice to o charge a 24v bank, what are the odds one or 4 in parallel would overcharge a 24 v bank, I don't have a controller yet, I was going to wire them up tomorrow while I'm on site, if I leave them plugged in for 3 days would they reach some 28+ v and overcharge those batteries? I know it's unsafe just speculating that's all.

                              The other thing is I am not dead set o 4 pannels if a series of 3 would be be bettbe suited for a common controller, or 2 or 3 strings of 3 if I am not exceeding the amps now I'm all ears, as I said I am not familiar with what equipment is available, in hoping for some suggestions save some time lookin at various components and reading all the specs cs and reviews
                              Last edited by georgerc; 04-24-2017, 09:54 PM.

                              Comment

                              Working...
                              X