Thought process getting here was, we are kind of interested in a nat gas generator for the whole house. Well, that should be around 10k. Solar, after the Al Gore incentives, should be somewhere around 25k, with a break even time around 10-15 years. If I factor in the ten grand for an emergency generator, that makes my break even time around 7-8 years, which seems like a pretty good deal.

Problem I just discovered is that when the power goes out, your solar stops. This is to stop back feeding the grid and frying the Wichita lineman. I get that, but that totally negates my reason for solar. Is there no kind of transfer switch? I see there are big ass battery banks, but they are expensive, I haven't seen a life expectancy on them and they only last half a day. Any way to bypass this cut off feature, providing you have a switch in place to the grid open. Would something like that void the warranty? Seems very short sighted not allowing for a solution.

Have you factored in the overcast skies we had for days during the winter storm? I don't think your solar would be doing much during that time. I'd go nat gas for emergency backup.

Project we recently had wanted solar and generac battery backups. They had to have a separate solar circuit to feed the battery backups that had the auto transfer in it.

It seemed odd to me that they are not the same circuit that back feeds the entire building.

Solar without storage really isn't practical on a small scale. It's not stable, every time a cloud passes by you would lose a chunk or all of your power, that's hard on electronics.

If you are looking for any kind of power security, you need the batteries.

This is my understanding. If your main goal is backup power supply, a natural gas generator is your best option. As you noted, much cheaper. If you are mainly interested in reducing long term energy cost then solar is good where you can feed the grid.

You would need probably 2 or more batteries like a Tesla power wall which makes the $$$ even higher. Great if you want to but if you're looking purely at $ and practicality then you're looking at nat gas all the way.

Several houses in our neighborhood put in solar after the great freeze. No storage.

I laughed myself silly when we had a power outage in March and they discovered their solar didn't work at all when commercial power was out. Greatest neighborhood Facebook post of the year. Which was even better after they bragged on the neighborhood Facebook page how smart they were for getting solar.

For whatever reason, Solar and roofing seems to be going together these days. I don't do it and I don't recommend it. Seems like solar is the biggest scam going these days. So many people spend a crap ton of money or finance out of decades, yes decades, only to find out they'll never make their money back, it won't work when it needs to, and it's generally a waste of time and money.

If you need emergency backup, buy a generator. They work. All the time. And they don't cost an arm and a leg by comparison.

If you do get solar, and you need a roof, call me, I LOVE doing roofs with solar, especially if it's an insurance deal, it's a huge money maker. O&P, disconnects, dismount, remount, cha ching!

A strictly Grid-Tied system system is only operational when the grid is up, but you get to sell your surplus electrons back to the power company.

A separate system, [think remote, no power available] requires batteries, and often a generator for sufficient power [Amp Hours].

The best of both is a hybrid system, but requires a utility approved inverter, which of course is mucho expensive.

Would probably require close to 6 figures to get a large enough capacity system to run AC during the year.

So, there are no options for a system with a mid sized battery that would still use the grid, but when the grid fails, the solar would still work to feed the batteries, essentially running the house, and some sort of switch to keep power from feeding back into the down grid? It sure doesn't sound like that is an option now.

I believe a Tesla power wall fits your bill for that but I would think to run your whole house for any extent of time you would need multiple

Buy a natural gas fueled generator if you want whole house backup 7/24 for multipledays in overcast weather.

The new Tesla power wall is rated for about 13 kilowatt hours.
I don't own one and had to look it up, I couldn't find actual amp- hours and discharge rate limits.

4 ton A/C requires about 4 kWh.

So ideally , a fully charged powerwall could run JUST your AC for 3 continuous hours.

I don't know how much the Lithium batteries derate with heat & time.

There are other considerations, the powerwall inverter would have to be rated to handle starting Amps which are usually 3x running current.

Milwaukees Best Light said:

---

So, there are no options for a system with a mid sized battery that would still use the grid, but when the grid fails, the solar would still work to feed the batteries, essentially running the house, and some sort of switch to keep power from feeding back into the down grid? It sure doesn't sound like that is an option now.

---

Yes those options exist.


There is a large subculture of people using large scale PV & batteries that also feed into the grid.
You would need to spend $$$$$ on batteries and inverters.
Plus have the room for the equipment
Also would be wise to educate yourself on DIY inverter maintenance

Jason_InfinityRoofer said:

---

For whatever reason, Solar and roofing seems to be going together these days. I don't do it and I don't recommend it. Seems like solar is the biggest scam going these days. So many people spend a crap ton of money or finance out of decades, yes decades, only to find out they'll never make their money back, it won't work when it needs to, and it's generally a waste of time and money.

If you need emergency backup, buy a generator. They work. All the time. And they don't cost an arm and a leg by comparison.

If you do get solar, and you need a roof, call me, I LOVE doing roofs with solar, especially if it's an insurance deal, it's a huge money maker. O&P, disconnects, dismount, remount, cha ching!

---

During the 2021 freeze our natural gas fire place cut in and out because of low gas company local distribution system pressure (my wife works in mapping for the local gas distribution side of things). Could barely warm a living room, nevermind run a whole house. No system is perfect in perpetuity.

Were you hauling a ridiculous wake board boat down the PGBT earlier today in the F-250 with "ROOF4R" plates?

Negative. I'm work mostly San Antonio and Austin. I live in San Antonio. . Plus, At 5 bucks a gallon, my superduty doesn't leave my house without a genuine need for it. Brodozing a boat is absolutely not in the "do I need my diesel today" category. Im a low profile small town kinda dude. My money goes to horses, kids, and tractors. I do know that truck, but not who drives it.

As for the generator, I'm frustrated to hear that didn't work out. I know a handful of customers that got all these solar things because a sales guy sold it to them and they find out stuff like they can't sell it back to the grid, or it doesn't produce what it should…and the companies are ghosting them. It's pretty much the hack roofer gig for electricity.

Generator
Propane Tank
Wood Burning Stove

These three things should keep you going for power failures.
When I build my "forever home" I'm going to include those plus really work on the design of the home to be appropriate for Central Texas. (High ceilings, porches, rainwater capture, designed to funnel winds, good thermal mass & insulation to require less heating/cooling)

I know people are dumb. So not necessarily doubting that people got duped in the selling power back vs. not having storage to switch to when the power goes out.

But....I feel like that is common knowledge. Especially post freeze, several posts were trending on social media regarding it.

Solar is super pricey; however, if things in our beloved country continue down the crazy train...it might be your only option. Interesting concepts out there today with prtable solar generators (3kw inverters) = see Ecoflow, Bluetti and Point Zero. These syatems minus the extra batteries that can be purchased are around $3k+. Usually you can figure $1/watt.

Then there are the all-in-one solar inverters/mpp systems. These have more power, but not portable. Siganture Solar in Sulphur Springs, Texas sells some of the best (I am not related in any manner to these folks, nor do I know anyone there). I did buy some used panels from them last year though...$35/each.

The Signature systems will run you:

1. All in one inverter = $1,200 for 6,500 watts (48 volt)
2. Battery = $1,500 for 5.1kwh (48 volt). These are Lithium Iron Phosphate which in my study is the only chemistry you should consider (currently). Typically has design life around 10 years or 5,000 or so cycles = marketing.
3. Solar Panels...so many to choose from but in the 400 watt range these days per panel and run a few hundred bucks each.
4. Wire = Cu is expensive
5. Electrician for transfer switches and what not


Note: I would choose to have a system separate from Grid. These grid folks getting mad at lost revenue from solar and I have read stories they will shut your access off if they know you have solar. Not sure of true, but as wild decisions are made constantly in this world, it would not surprise me.
Lastly, if you want grid tied system you should look at SolArk which is very pricey.

normaleagle05 said:

---

Jason_InfinityRoofer said:

---

For whatever reason, Solar and roofing seems to be going together these days. I don't do it and I don't recommend it. Seems like solar is the biggest scam going these days. So many people spend a crap ton of money or finance out of decades, yes decades, only to find out they'll never make their money back, it won't work when it needs to, and it's generally a waste of time and money.

If you need emergency backup, buy a generator. They work. All the time. And they don't cost an arm and a leg by comparison.

If you do get solar, and you need a roof, call me, I LOVE doing roofs with solar, especially if it's an insurance deal, it's a huge money maker. O&P, disconnects, dismount, remount, cha ching!

---

During the 2021 freeze our natural gas fire place cut in and out because of low gas company local distribution system pressure (my wife works in mapping for the local gas distribution side of things). Could barely warm a living room, nevermind run a whole house. No system is perfect in perpetuity.

Were you hauling a ridiculous wake board boat down the PGBT earlier today in the F-250 with "ROOF4R" plates?

---

Haven't heard many people talk about this, but I've wondered about the natural gas supply/pressure because of things I heard during the freeze. Probably a lot of this was dependent on your location. It's still the best option for most people in a city. As you said though nothing is perfect.