Our solar system

[Mike J]

We have been planning on installing a solar system and finally took the plunge.  The system is 5KW, 10 550watt panels, 5.5 kw inverter, and 200 amp/hour battery at 51 volts.  You can review what is happening using an app on your phone.  Less than two weeks since the install but it appears we are using solar energy for 85 percent of our electric usage.  The vendor has remote WIFI access to the unit in case of issues or required adjustments.  Working with the vendor to increase the amps pulled from the battery after dark.  I think we can get to 90-95 percent solar.  Installed price was 335K peso.  Kind of anxious to see how it performs in the next brownout. 

 

[Tommy T.]

Looks good Mike. I have a few questions:

Do you have and use air/con? If so, how often do you use it? How many do you have and about how many square feet are you cooling on a regular basis?

This includes powering fridge and freezer?

TV, computers, modem also use a fair amount of power. How much of this sort of thing do you have?

Are you feeding back to the grid or is your system separate from it?

Thanks!

[Old55]

Nicely done Mike! Curious to learn more.

[Mike J]

7 minutes ago, Tommy T. said:

Looks good Mike. I have a few questions:

Do you have and use air/con? If so, how often do you use it? How many do you have and about how many square feet are you cooling on a regular basis?

This includes powering fridge and freezer?

TV, computers, modem also use a fair amount of power. How much of this sort of thing do you have?

Are you feeding back to the grid or is your system separate from it?

Thanks!

We have not used AC since it was installed due to cool rainy weather.  Even during full cloudy weather the panels have provided 100% power during the day.  Load during the past 10 days is 2 refrigerators, multiple lights, two ceiling fans all day, 1.5 KW pool pump for 2-3 hours each day, 2 lap top computers, water dispenser (hot/cold).  I plan on turning on our air conditioners and pool pump at the same time.  We have three AC, 1 large one in the master bedroom, and two small ones in the guest rooms.  Our plan in to now install a split 1.5 AC in the large living room.  I will post the results of the testing as I proceed.  It is interesting to see the phone app as the load changes.  Because we do not feed back to the grid, our inverter provides/records the power required for the load and any charge to the battery.  For that reason is is hard to say how much power is actually being produced as we are measuring what is being consumed.

[Tommy T.]

Just so you know, Mike, I did a listing out of all our daily electrical usage in our rather small home. It came to 14,500 watts! And that included only one air/con unit our of four that we have, but the only one we use every night. I had forgotten about rice cooker, air pot, shower water heaters, washing machine, which are big users.

Edited July 15 by Tommy T.
Added in "daily"

[Tommy T.]

Does your system automatically switch from grid to battery in brown or blackout?

To me, it sounds like you may need to add another battery and panels once you include the new air/con.

But I could be wrong...looking at what you posted, I think we use more power than you and maybe that's the difference?

[BrettGC]

4 minutes ago, Tommy T. said:

To me, it sounds like you may need to add another battery and panels once you include the new air/con.

My thought exactly.  Mike I'm wondering if your batteries are charging to 100% during the day?  And if not the pretty much constant overcast weather recently may be impacting it.  

I know my parents can get about 36 hours out of the batteries in a similar climate to here, but just a little chillier in the "winter" months.  They're feeding power back into the grid.  2 TVs, 2 fridges, 1 AC, and all the other normal stuff in most 3 bedroom homes as well as a pool.  Having said all that, they covered their roof entirely with panels and the battery setup takes up a lot more space than yours does.  They've only had to use mains power twice in the last 5 years and that was due to extended periods of rain and flooding.  I'm pretty sure it's a 15kWh battery rather than 5 like yours.  

[Mike J]

Finished test at 10:00 am.  Seeing what our max use would be.  Turned on everything in the house.  Three aircons (1 large, 2 small), 1.5 horse pool pump, six over head fans, two refrigerators, 2 laptops, every light in the house (1200 square feet).   Sky is cloudy maybe 70-80 percent clouds.  With "everything on" we are using 4.5KW, generating 2.2KW from the panels, and 2,4 from the battery, and 28 watts from the grid.  During the day, even when cloudy, the battery typically goes to 100% and stays there.  This is the first time I have seen power come from the grid during the day.  I think on a sunny day we would pull close to the 5KW from the panels.  I have not seen the battery go below 70% which seems odd to me.  I was think with a lithium battery you could pull down to 20%.  

Edit - Test finished, turned off the three AC, everything else still on.  Using 1.2KW, solar producing 2.9 KW, battery is charging at 96%, nothing from the grid.

Edited July 15 by Mike J

[Tommy T.]

19 minutes ago, BrettGC said:

My thought exactly.  Mike I'm wondering if your batteries are charging to 100% during the day?  And if not the pretty much constant overcast weather recently may be impacting it.  

I know my parents can get about 36 hours out of the batteries in a similar climate to here, but just a little chillier in the "winter" months.  They're feeding power back into the grid.  2 TVs, 2 fridges, 1 AC, and all the other normal stuff in most 3 bedroom homes as well as a pool.  Having said all that, they covered their roof entirely with panels and the battery setup takes up a lot more space than yours does.  They've only had to use mains power twice in the last 5 years and that was due to extended periods of rain and flooding.  I'm pretty sure it's a 15kWh battery rather than 5 like yours.  

I will add a bit more to what Brett posted, Mike.

I am fairly familiar with solar since I built my own, maintained and controlled it for my yacht. Admittedly, it was using a tiny load, even compared to yours. However something I learned is love and care for your batteries. They should not be drained past 50% capacity often. Doing so will dramatically shorten the life of it (them). Are they lead-acid or solid or gel? As I posted some time ago, I swear by - not at - the gel batteries I used. They are abuser friendly although perhaps the most expensive out there? I don't even know if they are available here.

[Tommy T.]

2 minutes ago, Mike J said:

I was think with a lithium battery you could pull down to 20%.  

That's another story. I have no knowledge about lithium batteries other than the ones in all our gadgets and computers. I would be cautious with them in a big use like home solar system.