The Greg's Grid Tie Solar Project

[Gregski]

Hope to share my experiences with solar powerism from the total newbs perspective Greg style. The goal being alleviate all the intimidation and hubub dealing with solar system installations. There will be no talk of ROI or ROwe on this thread, this is going to be as simple and as inexpensive as it gets, we will take baby steps, and hopefully we can learn together. Please read most of the words before commenting as some pictures may not tell the whole story.

Background: I hail from California the land of regulations, ha ha my day job is a computer geek but I know which end of a screw driver to hold and I aint skierd to try new things, I also love learning and enjoy making things myself (some say I don't like money)

QUESTIONS:
(this section will expand as we go along)

• What the hell is a grid tie system?
  • one that requires no batteries

• Well, how much you gonna spend?
  • hopefully less than $1,000

• Do you need a license / permit for that?
  • Hell no, well (maybe)

• Is it safe?
  • Yes, the system shuts down when you shut down the mains in your electrical panel for service.

• Is it legal?
  • Check your local ordinances I guess

red tape.jpg (18.19 KiB) Viewed 22546 times

• How does it store energy?
  • It doesn't

• Does it work at night?
  • No

• Can you use it as a backup system when your grid power goes out?
  • No, it shuts off for safety when the house looses it's normal power from the utility company

• Can you use more than one of these inverters?
  • Yes absolutely, of course: Shane Mason's Grid tie inverter update

• Does the inverter come with any management software?
  • Not this one but the micro inverters do, however we have a solution for that, please start by looking at the Kill A Watt meter

• Does the inverter have WiFi?
  • Not this one but the micro inverters do, however we have a solution for that

• Does the inverter have Bluetooth?
  • No, but we have a solution for that

• What power levels do these inverters come in?
  • 300, 500, 600, 1000, 1300, and 1400 watts

RULES:

1. Don't get dead!

2. When in doubt, refer to Rule #1.



THE PLAN:

buy one solar panel a month (on a two kids in college man's budget) until the inverter can take no more, or the patio cover collapses


this is just a guy who took the plunge before I did:

[Gregski]

so it all started with a solar panel, yes ONE

I literally went out on AMAZON and bought the cheapest 100 watt solar panel I could find [May 2020 BC (Before C0v1d) $77 bucks), it just happened to be from a company I guess you can call them that, that calls itself WindyNation

My requirements: buy a 100 watt solar panel so I could do the math easily as I add them up, 100 watts, 200 watts, 300 watts you get the idea

again I knew nothing at this time

[Gregski]

LESSONS LEARNED:

Lesson #1. there are two types of solar panels (probably more but at least two) later on we will learn more about this but for now we have:

1. Polycrystalline (we'll just call it Poly)

• it tends to look blueish

• has white grid lines on it

• old tech

2. Monocrystalline (we'll just call it Mono)

• it tends to look blackish

• has white grid lines and little diamonds on it

• new tech

there, how's that for Science for ya?

[Gregski]

... and now some Solar Panel Math (SPM)

One solar panel = $79.99

but wait, if you act now, and buy two of them, it's only ten bucks more than if you bought them individually = $169.99

do you see the service I provide here?

[arber333]

OK that is .... strange?
Shipping and packing... and repacking from aliexpress maybe?

[muehlpower]

1 kWp should be available for around €500 ($).
I recently bought 46 modules with 375Wp for €179.- each.


How much does electricity cost in sacramento?

[Gregski]

1 kWp should be available for around €500 ($).
I recently bought 46 modules with 375Wp for €179.- each.


How much does electricity cost in sacramento?

thank you and I am glad you asked, we pay an average of $200 per month, and that is a great segue into the section on reading your Electricity Bill, in Sacramento we can get our electricity from one of two companies, mine is called SMUD (pronounced like mud just with an S in front of it) Sacramento Municipal Utility District, and their pricing strategy is what you would get if a Credit Card Company and your Cell Phone Company had a child aka confusing, I happen to have something they call Time-of-Day (5-8 p.m.) Rate which comes in either their Summer or Non Summer flavors:

this is my January 2022 usage calendar that I made based on their utility bill with a daily average for the month of 17 kWh, I said I made this because their billing cycle is deliberately confusing and spans across two partial months type of thing: the big numbers are kWh (we have a larger two story house which faces North)

[Gregski]

OK that is .... strange?
Shipping and packing... and repacking from aliexpress maybe?

actually we learned about this in Marketing class back in college, it's the buy one balloon for $1.50 or three for $5.00 dollars, and people gravitate to buying the bunch of three thinking they are saving money, it's just a trick

[Gregski]

THE BASICS

so there are bazillion of solar system spec combinations, let me give you an example of a few of them and we will start with the most basic one of them all

100 watt 12 volt panels and 12 volt grid tie inverter (we will be using this one)
100 watt 24 volt panels and 24 volt grid tie inverter
200 watt 12 volt panels and 12 volt grid tie inverter
200 watt 24 volt panels and 24 volt grid tie inverter

etc....

Grid Tie simply means No Batteries needed, that's right this system is so basic, so simple, there are absolutely no batteries at all, this is why I was so excited to try it, and share it with you all.

[Gregski]

so all you need for this Grid Tie system to work is two things:

1. Solar Panels
2. a special grid tie Inverter

so I went out and bought this 1000 watt grid tie inverter from a company that called themselves "Vevor" (more on this later but these days I see half a dozen fake name companies selling the exact same box type of thing) again off of AMAZON for only $104 bucks, keep in mind this was before the pan dem ick

once again like a fool I only picked the 1000 watt unit based on it's round number spec and nothing else, I think there may have been a smaller 500 watt one as well that I passed on

[Gregski]

BUDGET CALCULATIONS:
so at the time the idea was

10 panels at $77 bucks each = $770
1 inverter at $104 = $104
subtotal = $874

leaving $126 for cables taxes or doo dads, as we would grow GMUD (Greg M's Utility District)

[Gregski]

so as the months went by, I would get one new panel every month and throw it up on the patio cover, yes flat, totally horizontal, yes I'm a moron

again this is full disclosure and we learn from our mistakes, at least my back yard faces South, that in the Northern Hemisphere turns out to be desirable (more on this later)

the patio cover is big, so I thought I would cover it all with $100 dollar 100 watt solar panels, and start selling electricity back to our utility company, and make millions !!!

[muehlpower]

How about a real system. 12 modules with 375W each, an inverter with battery charger and backup power function and an 11kw battery. The sun always shines in California, I heard. That should make you independent of electricity and costs around $10,000. You save at least 20kWh x 365 days x $0.15 = $1100. The system is amortized after 9 years.

In Germany, electricity (still) costs €0.30 per kWh, so you get the money back even faster! But the sun shines less

[Gregski]

How about a real system. 12 modules with 375W each, an inverter with battery charger and backup power function and an 11kw battery. The sun always shines in California, I heard. That should make you independent of electricity and costs around $10,000. You save at least 20kWh x 365 days x $0.15 = $1100. The system is amortized after 9 years.

In Germany, electricity (still) costs €0.30 per kWh, so you get the money back even faster! But the sun shines less

I appreciate that and just being honest with you I have no idea what a "real system" costs, I do know however that with two kids in college this house is way too big for us, and we will be retired in less than 5 years, so will never see the break even in this house. Also not trying to argue but I doubt the $10,000 incudes all the permits and HOA (Home Owners Association BS) we would have to deal with, maybe even requiring a professional installation so at least double that cost. I may get some quotes just for funsies.

[zippy500]

So the question is:

Is it better to grid tie or use battery storage and use in the stored energy in the evenings ?

[arber333]

So the question is:

Is it better to grid tie or use battery storage and use in the stored energy in the evenings ?

Well...

1. Grid tied systems are usually quite large and (at least in EU) 3phase. You have your 30ish 350W panels, 16kW inverter and no battery! Sorry i have no knowledge of hybrid systems... But that means a lot of energy goes with the sun. Downside is that you have your solar grid dependant, since if your network goes, solar will shutdown, protection for maintenance and safety... there is the price too...

2. Island type battery powered solars are a lot smaller. Usually 12 panels and 2x 5kW inverters in parallel + 20kWh Lifepo battery.
Usually complete solar power is therefore some 8kW and in the real more like 6kW... But system works off the battery and in case of power outage you have your UPS! Also with a bit of clever switching you can provide generator power and slowly charge your battery in case of winter snow etc...
But this includdes the price of battery not just the system...

Lot of options for island type and really only one option for the grid tied...

[muehlpower]

There are now hybrid inverters that combine both. The solax x3 hybrid devices I use have DC connections for the battery and PV generator. One AC connection for the grid and one for important electrical equipment. The battery is charged by solar power without DC-AC-DC conversion. In the event of a power failure, the important devices remain live. In this case, the solar energy is also used for charging or for direct consumption. An island operation is created. A self-consumption-optimized operation can be set, which means that the PV and battery are used first and the rest is drawn from the grid. PV surplus is fed into the grid, if you want.

I don't know if that's profitable in America, since the electricity costs less than half and I don't know whether grid operators pay for the electricity fed into the grid. In Germany we get up to 14 cents per kWh.

I use two of the 15 kWp versions together with a 17.4 kWh battery and 33kWp PV modules.

[Gregski]

[Gregski]

for funnsies here is a little HISOTRY or Chronology of these grid tie inverters, I have tracked them back to 2014 let me know if they go further back

I honestly just recently saw these SUN units (funny how YouTube works, you can't find what you need when you search for it, then it magically appears a few days later in your recommends)

Model: Sun-500

presented by Jeff from Missouri Wind and Solar back in Apr 9, 2014 Sun Grid Tie Inverter Plug and Play Install | Missouri Wind and Solar






Model: Sun-600G on eBay

Model: Sun-1000G on eBay

[Gregski]

oh the joys of trying to contact Technical Support, here I am attempting to chat with a Southern California company which calls itself NewPowa, by the way I live in the same state, and it was after 8:00 am:

THEM: Hi there If you need any assistance, I'm always here... please introduce yourself:

ME: I am looking for a Grid Tie inverter, one that I can use without batteries

THEM: Sorry, we’re currently unavailable. Please contact us at 702-628-7600 (9.00 am - 5.30 pm, PST).

[Gregski]

THE MINIMUM $200 DOLLAR SETUP

man learning about this is so much fun, so today I decided to see how much sun could a Greg catch if a Greg could catch some sun with just one panel, a blue Polycrystalline mind you (pronounced: "older less efficient supposedly technology")

Full Disclosure: yes I made a part time job of it, as I kept moving it manually to ensure full sun catchability, but that was not the point, the goal was to see how wide I could cast this single 100 watt 12 volt panel net and how much sun I could capture

this took place in Norther California in August 2022

• so in the morning we started around 7 am and the panel was pointed East

• around 11ish we pointed it South

• and maybe at 4ish we pointed it West

no I am not going to rotate all 10 or so of my panels eventually manually, this was just a fun little test

[Gregski]

THE MINIMUM $200 DOLLAR SETUP

so one panel/inverter combo pulled, produced 672 Wh of energy in one day, my inverter cost $104 and that panel cost $92 this means that for $1,000 dollars I can get one inverter and 9 panels so this $1000 dollar system has a potential of generating 672 x 9 = 6,048 Wh or 6 kWh for short in one day that's amazeballz

of course this $1,000 limit is just some arbitrary number I came up with so my next goal is to keep adding panels to this 1000 watt inverter to see what's the most watts it can invert, knowing a 1500 watt house circuit is my limit (120 volts x 15 amps circuit x .80 safety margin = 1,440)

[Scrappyjoe]

I bet you 20 imaginary bucks you pop your inverter with 9 panels. I mean I hope I’m wrong but it seems too good to be true given the insane quotes I’ve received for an installed 5kw solar system.

[Scrappyjoe]

Surely you mean you captured .672kWh with your single panel? Aka 672Wh?

[Gregski]

I bet you 20 imaginary bucks you pop your inverter with 9 panels. I mean I hope I’m wrong but it seems too good to be true given the insane quotes I’ve received for an installed 5kw solar system.

that's exactly why I am doing this to prove that you don't need to spend booku bucks on this, you're on, challenge accepted, and nothing says you can't use multiple inverters, so even if you run 5 of these that's only $600 bucks

I bet I will be able to connect as many as a dozen to this beauty, keep in mind these 100 watt panels pull at 70% efficiency at best so 70 watts each if that, I had 6 connected already and plan on reconnecting 6 today I took things apart to add these meters on the DC side