Where to begin: PV Direct or a bigger build

Silva99
Silva99 Registered Users Posts: 2
First, let me say how impressed I am that the folks here take the time to help people get started. Very heartening.
I did not see this topic, though my search skills could probably be improved.

I am interested in advice on whether to get started small, with PV Direct to a few key appliances to put a big dent in electrical bill or make a bigger build.  I have electrical experience but no solar; anything I say below will be me faking it. ;)  I have the financial means for a bigger build, but don't like to throw-away money and plan to do mostly DIY.  

So, key info: Central Virginia location.  8 acre south facing home site but mostly trees may require some clearing if ground mount.  4000sq foot house. 15KW south facing roof (passive solar house has mostly north facing roof), but metal roof tiles.   Seems like a difficult roof install if you ask this noob.  And south facing 400sq foot greenhouse solarium.  

Older water tank.  3 air conditioner / heat pumps.  One we never use because I have installed a fan in the solarium that pumps excess heat into basement.

My thoughts were to 'just get started' installing a dual mini-split in bedroom and next door office and possibly running that PV direct with about 8 panels going through inverters.  Would warm up the office in the morning in the winter, and cool both rooms during the day in the summer.  No batteries means it's not working at night or tail ends of the day.  I have no idea if this might make a substantial dent in my power usage.  Obvious upgrade is to connect a battery to same system.

Also looking to generate hot water from solar with direct PV.  Either A) replace water tank with a dual element tank and run inverter from panels to tank.  Connect to grid with other element set at different temp.  Or B) consider the sunamp heat battery.

Finally, also playing with the idea of a larger dual sunamp heat batter to then run 2nd circuit to water/heat exchanger(s) and run heat pump in fan mode.  

VS a much larger system with battery backup running through SolarArks.  Will take a lot longer.  More expensive startup.  Permitting hassles. et.al.

OK, burst my bubble.  Seriously, you will save me time and energy by disrupting my thought process on this if it totally doesn't make sense.

And, you're welcome if you got a good laugh.

cheers


Comments

  • Silva99
    Silva99 Registered Users Posts: 2
    I forgot to add, also considering PV Direct to chest refrigerator and small battery/generator for kitchen fridge backup  Current older chest refrigerator pulls 275 watts and runs a lot.  Considering replacing it.
  • Photowhit
    Photowhit Solar Expert Posts: 6,006 ✭✭✭✭✭
    Trying to do PV without batteries is really not possible. Generally they would require special appliances to run directly off DC electric. Inverters would not deal with running through an inverter without some means of constant current to deal with fluctuations. The grid tied micro inverters only work when they can see and match the sine wave of the grid. Enphase has a new system that may work but they are only installing it with a battery bank in the US, last I heard.

    Sounds like you want to save money, it's rare to do this without a grid tied system. Off grid systems tend to cost more for the electric they produce. This, in part, is because they must be designed to provide more electric than can be stored.

    If your goal is to save money, it's almost always best to consult your power company and have an energy audit done. Then spend your money in reducing your energy use, More insulation, better sealing, replacing old appliances. Geothermal heat pump...
    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.
  • NANOcontrol
    NANOcontrol Registered Users Posts: 273 ✭✭✭
    This is a specialized field for those who really know electronics.  I run a chest freezer only in the day with just a small battery only for surge current and only when the battery is full.  A large washer off an array with no battery and all my hot water is from PV no inverter or battery and only when there is excess power not needed.  The washer has its own 40 gallon tank and all cycles are done with hot water. Cloths come out steaming from the spin cycle. MY dishwasher heater element runs off PV voltage so I have heated dry. A friend in FL runs his dryer heater element off solar.  It is neat to do, but you just can't run off to amazon to do it