Experience with Solar Panels?

[DLHDesign]

Ah; I see your question.
Yes; that's basically true of solar systems and PG&E - if you hook up a solar inverter to the house line, you don't get a backup against power outages - just a reduction in your energy bill. When I asked about that back when, I was told that it's because grid+solar can overload the system and/or cause issues with the grid during an outage. So it basically gets set up that when the power goes out, the DC inverter looses it's power source and doesn't produce power (even though the panels are collecting/generating DC power, there's nothing to provide the trickle of A/C power needed to turn all that D/C into A/C - or something like that...).

When the Tesla battery was installed, all that changed. The battery can provide that trickle of A/C to the inverter, which allows the D/C that the panels are producing to be turned into yet more A/C. In other words; with the battery installed, the solar panels (and the battery) provide power to the house during an outage. I've had several outages since the battery was installed (not to mention shutting off the grid when we installed it as a test) and every time the system picks up the draw and the house runs without interruption.

And according to some, Fremont, of all places since this is where Tesla is, does not allow install of batteries to your solar setup.

I would be very surprised if this is actually true. Fremont recently passed a resolution that all new construction had to be net-zero (meaning they pretty much have to have solar) and (IIRC) that they be EV ready. It wouldn't make sense to me that a city council passing that type of policy would prevent batteries from being hooked up.

I also have a 20 year old house and may have to fix the roof sooner or later, and having the panels may be a hassle.

Yeah; I wouldn't suggest doing anything until the roof is in good condition. Installing the panels, just to have to take them off and reinstall them would really make it hard to get them in the black. And doing it yourself - which certainly possible (I did ours) - isn't so easy that I'd think anyone would want to do it twice (plus a removal)...

 

[jd371]

Thanks guys. I am still shopping around and haven't made any commitments yet. One company's proposal is looking pretty good with the output from the panels supplying all our power needs (with the trimming or removal of 2 trees) and having it paid off in 12 years. Still want to talk to my accountant about the rebates and run it by the lawyer as well. I'm also just thinking of scrapping this idea for now and just getting energy efficient appliances and LED bulbs throughout the house.

 

[DLHDesign]

I'm also just thinking of scrapping this idea for now and just getting energy efficient appliances and LED bulbs throughout the house.

Your money will go farther with new appliances, bulbs, etc. Insulating walls, ceilings, etc. Most of that has a much faster and higher ROI.

In general, I recommend that you reduce your draw before you look to replace your input. That allows you to reduce the size of a system install as well - which is even more savings. You're unlikely to find that selling energy back to a producer is actually profitable, so having a grossly over-sized system (which you could have if you installed solar first and then reduced your draw) isn't really a good thing in the long run, IMO.

 

[doughboy]

Thanks Dave. very helpful, useful info.
my electricity usage is getting lower. We used to be family of 5. This fall, the youngest will go to college so we will be down to 2.
If I shut down the reef tank, I will be in tier 1 even now with 3 people in the house. And my son has his gaming computer on 24x7.
with low usage and old house, I'll skip getting solar for now.

with low usage though, even if net metering results in negative reading at TrueUp time, the $ amount may not be worth the trouble.

 

[doughboy]

Thanks guys. I am still shopping around and haven't made any commitments yet. One company's proposal is looking pretty good with the output from the panels supplying all our power needs (with the trimming or removal of 2 trees) and having it paid off in 12 years. Still want to talk to my accountant about the rebates and run it by the lawyer as well. I'm also just thinking of scrapping this idea for now and just getting energy efficient appliances and LED bulbs throughout the house.

when I got all new appliances, I was able to negotiate lower than sale price at our local Fry's electronics. The salesperson got a good chunk of commission. I think if you have anything older than 10 years old, then new models will be much more efficient. our appliances were like 18 years old when I replaced them. And yes, LED lighting will save quite a bit, even compared to CFL, and they are cheaper now on Amazon.

 

[jd371]

Your money will go farther with new appliances, bulbs, etc. Insulating walls, ceilings, etc. Most of that has a much faster and higher ROI.

In general, I recommend that you reduce your draw before you look to replace your input. That allows you to reduce the size of a system install as well - which is even more savings. You're unlikely to find that selling energy back to a producer is actually profitable, so having a grossly over-sized system (which you could have if you installed solar first and then reduced your draw) isn't really a good thing in the long run, IMO.

Sound advice, thank you.

 

[Mattrg02]

Buying solar to reduce ones electric bill is, in all cases that I’ve seen, been a bandaid to a problem at home. It’s like trying to get a raise at work, when you really aren’t due for one, in order to pay off debt instead of reducing wasteful spending at home.

One of the reason that utilities mandate that your system shut down in the event of a power outage is because lineman are working on the lines. If your 10kW system is feeding the grid, you’ll put them in a dangerous situation. You may also keep a down line energized which would probably kill someone who gets too close. Another is that your system will essentially try to supply all of your neighbors. This will overload your inverter and likely cause damage.

Whenever someone tries to sell you on something, do the payback math yourself. These “salesmen” are oftentimes “fly by night” dudebros that overestimate and exaggerate the truth. Check your $/kwh, on your bill, before you let someone figure your ROI using 0.35$/kWh :)

-Matt

 

[DLHDesign]

One of the reason that utilities mandate that your system shut down in the event of a power outage is because lineman are working on the lines. If your 10kW system is feeding the grid, you’ll put them in a dangerous situation. You may also keep a down line energized which would probably kill someone who gets too close.

All good (and true) points. Though it really doesn't require that the system shut down - just that it not feed back into the grid. Because of the way that most systems are wired, however, this isn't usually a practical solution - it requires switches and sensors and such which the standard install doesn't include (the inverter wires just plug into the circuit(s) directly). One advantage of the battery system is that they have all those sensors and switches, so you get the "solar power is on even when the utility is down" solution.

Another is that your system will essentially try to supply all of your neighbors. This will overload your inverter and likely cause damage.

This part of your statement is actually not true - the inverters will only provide as much power as they can produce. You can't over-draw them, in other words - even if your solar array is larger than the inverter can handle (which would be a bad install from the start), the inverter would cap the draw to what it can handle.

Just to make sure it's been said; you can install a Tesla Powerwall (and I would assume many other backup systems) even without solar. In the case of the Powerwall, it includes software that allows you to use it as a primary energy source not only during power outages, but also during peak times when power is expensive. Basically gives you a "time of use" toggle that you configure based on your own needs. I've not run the numbers (as it wasn't applicable to me), but I'd suspect that in some situations where a full solar system doesn't compute, just installing a battery backup with that type of feature might. Not to mention; you get uninterrupted power in the case of an outage - to save the fish tank, of course. ;-)

 

[Mattrg02]

All good (and true) points. Though it really doesn't require that the system shut down - just that it not feed back into the grid. Because of the way that most systems are wired, however, this isn't usually a practical solution - it requires switches and sensors and such which the standard install doesn't include (the inverter wires just plug into the circuit(s) directly). One advantage of the battery system is that they have all those sensors and switches, so you get the "solar power is on even when the utility is down" solution.


This part of your statement is actually not true - the inverters will only provide as much power as they can produce. You can't over-draw them, in other words - even if your solar array is larger than the inverter can handle (which would be a bad install from the start), the inverter would cap the draw to what it can handle.

Just to make sure it's been said; you can install a Tesla Powerwall (and I would assume many other backup systems) even without solar. In the case of the Powerwall, it includes software that allows you to use it as a primary energy source not only during power outages, but also during peak times when power is expensive. Basically gives you a "time of use" toggle that you configure based on your own needs. I've not run the numbers (as it wasn't applicable to me), but I'd suspect that in some situations where a full solar system doesn't compute, just installing a battery backup with that type of feature might. Not to mention; you get uninterrupted power in the case of an outage - to save the fish tank, of course. ;-)

Tell that to the installers in my area. They complain to us that our reliability issues cause damage to their clients inverters when our protection devices go through their steps, open/close, before remaining open, thus causing their array to feed into a faulted line.

Ever priced a Tesla battery? I’d much rather have a propane generator for backup power.

 

[DLHDesign]

They complain to us that our reliability issues cause damage to their clients inverters when our protection devices go through their steps, open/close, before remaining open, thus causing their array to feed into a faulted line.

Not really sure specifically what you're referring to here, but it sounds like you have more personal experience than I do at a technical level, so - sure. :)

Ever priced a Tesla battery? I’d much rather have a propane generator for backup power.

Yes; I have. I have one installed on my current house and have two scheduled to be installed in my new house currently under construction. After rebates, the one I have ended up costing me just under $4k (with no ongoing costs). The payoff on it is within it's warranty period of 10yrs. A comparable propane generator is likely in the $2.5-3k range from what I can tell? Certainly both are viable options in terms of supplying power during an outage; no doubt.

 

[jd371]

Thanks all, we've decided to just replace old appliances and lighting for now and hold off on the solar panels.

 

[Radman73]

We installed 67 300w panels back in February and couldn't be happier. This past bill we finally had to pay for electricity again because of heavier than normal rain in May. We financed our system but are saving anywhere from $75-$150/month over using the power company.

We have a bi-directional meter than spins backwards during the day and forward at night.

We kept looking for the "catch" as it seemed too good to be true. For us, it's delivered on its promise at least to begin with. We purposely went with an oversized system.

 

[DLHDesign]

We kept looking for the "catch" as it seemed too good to be true. For us, it's delivered on its promise at least to begin with. We purposely went with an oversized system.

Sounds like my experience. I think (read: anecdotal opinion) a lot of the negative reviews around solar installs come from those who had one of the "big names" install their system. There is a steep markup and they will generally only install a system that is no more than 15% over your current annual usage (at least, that was the max the three I talked with would do). The +15% doesn't really cover for weather fluctuations and the extra markups really price the system out of profitability. The two factors combine with the turn-key designs meant for quick turnaround to yield a less than ideal install.
That's my fear with my new house... The builder is paying for the 3kWh system, so it's not that it'll be costing me anything. But if it ends up being a hassle to deal with or under-performs because they used some crappy panels, will I have the drive to replace the system with what it should be? Who knows...

 

[Radman73]

Sounds like my experience. I think (read: anecdotal opinion) a lot of the negative reviews around solar installs come from those who had one of the "big names" install their system. There is a steep markup and they will generally only install a system that is no more than 15% over your current annual usage (at least, that was the max the three I talked with would do). The +15% doesn't really cover for weather fluctuations and the extra markups really price the system out of profitability. The two factors combine with the turn-key designs meant for quick turnaround to yield a less than ideal install.
That's my fear with my new house... The builder is paying for the 3kWh system, so it's not that it'll be costing me anything. But if it ends up being a hassle to deal with or under-performs because they used some crappy panels, will I have the drive to replace the system with what it should be? Who knows...

Yeah, have a neighbor that has the exact same size house with the same number of people living in it, but wants to put in a system 25% smaller and expect it to cover 100% of his bill. I've tried explaining a couple of times that his preferred size of system would require near ideal conditions every single day but he just hasn't gotten it yet. On the bright side, he can just add panels once he figures it out lol!

We went with a smaller, more regional installer and we negotiated heavily on the price. In fact, we teamed up with several neighbors to negotiate the price down as a package deal for all of us. At the end of the day, it actually made financial sense to do it. I was surprised it did and wouldn't have installed the system otherwise. The tax credit makes all the difference though it may have been dead even without it.

We only went to 115-120% over our normal usage. I forget exactly how much. We broke 130kwh production a few times back in April though now with our daily afternoon FL thunderstorms we averaged closer to 75-80kwh per day in June which will leave us shy per day by 10-20kwh through July and August if it keeps up at that pace. My hope is with the system fully up and running that Jan-May of next year builds up enough credits to cover the summer months. We didn't start full capacity production until beginning of March this year.

In any case, it's exciting. I might look into a couple of the powerwall's in lieu of a whole home generator. Need to give it another couple of years to see if we lose power again or not. We've only been here two years but Irma passed right over us and we lost power for 5 days. Even if I could run everything but AC, I'd be happy. A genny would cost us close to 15k by the time we buy a decent sized propane tank and bury it. Would rather just get a battery system.

 

[Tiger-Paws]

I use high output Kyocera solar panels exclusively, I have found them to be very reliable and their output is great. Like many here I seriously oversized my systems especially my home on the island of Antigua. Here in Texas I am at 130% of my normal needs, in FL 150% and on the island 200% because of the number of days of cloud cover and thunderstorms.

I do not back feed the grid anywhere so when the grid power goes down my system isolates my homes until the power has been restored for 15 minutes thus eliminating the power surge and initial dirty power from the grid.