Interesting. I think most people do micro-inverters (one per panel). I think these SPS devices probably need a string inverter.
Who has solar power at their home? Please chime in....
- Thread starter ozziegn
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nwdiver
Well-Known Member
I'm pretty sure that's a grid-tie inverter since he says in the video about how he didn't want to invest in batteries BUT they are practically identical on the outside.
nwdiver
Well-Known Member
SPS is a function of the string inverter and only that particular SMA inverter. As far as I know only SMA offers this type of function.
Ciaopec
Member
I, too, have the Sunny Boy 6.0 inverters (2) and (1) Sunny Boy 7.0. No batteries though; wish I had batteries as a backup but I can plug into anyone of the inverters during a power outage (as long as there is sunlight) and get power. FPL net metering out on Merritt Island. Power is $0.11 per Kwh and FPL buys excess at $0.02. I have a 20Kw system which powers the house (3 A/C units) and the car and yard tools. This is the start of my second year. The first year excess paid 5 months worth of electricity bills @$9.00/mo (taxes and fees). This year I will produce enough to cover all fees next year.
In addition to Tesla, if you need another number try Brevard Solar ( Solar Panels and Energy in Brevard County FL – Solar Power is finally affordable! ). They install as far west as Tampa. I was quite pleased with their price and service. Vet discount, too ,I believe.
In addition to Tesla, if you need another number try Brevard Solar ( Solar Panels and Energy in Brevard County FL – Solar Power is finally affordable! ). They install as far west as Tampa. I was quite pleased with their price and service. Vet discount, too ,I believe.
nwdiver
Well-Known Member
Ciaopec
Member
Thought I might use it during Hurricane Dorian but that turned out to be a non event here (not so for the poor Bahamians). So, no chance to use it. I really should just test it now rather than wait for the real need.
nwdiver
Well-Known Member
WVJohn
Member
You've already seen good info in the replies. Some other thoughts - - if you have a large lot or acreage, consider a ground mount system. No roof problems and it provides a shed for outdoor storage. If you experience power outages where whole house generators are common in your area, consider a battery array as back-up power instead of a generator. Battery back-up costs roughly $5,000.
Hobari
Member
Here's a report from Colorado, which has mandated net metering. I'm on my third year with solar cells and second year with a Model 3. Bottom line - during the entire time, I've not had one month where I consumed more electricity than we produced. Even with driving the Tesla every day and charging at night. We have been driving on sunlight for a year.
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Solar Edge.jpg
I've posted about my system elsewhere, but since you ask...
My situation is a bit unusual: Here in Kihei, HI, on Maui, we get lots of sun and have very high electric rates. It gets hot, but not Florida hot. Certainly not Arizona hot. The program for net metering is fully subscribed: The utility simply cannot absorb any more daytime consumer-produced power. And there's a minimum fee of $25/month. If you use less than the minimum amount of electricity you pay $25 each month. And they add on $1.17 "Green Infrastructure Fee for a total of $26.17. I don't know of the GIF is an added charge for people who have solar, or if it's a system-wide fee to pay for the wind chargers on West Maui Mountain, which feed into the grid.
Most of my electric use is air conditioning. I don't put a lot of miles on the car (it's a small island) so the car doesn't take a lot.
I have 32 panels on the house and because I don't get net metering, I have two Powerwalls, which keep my house going all night. An hour after sundown I shut off the A/C because the house remains comfortably cool all night until late morning the next day.
The reason for not charging a car from the batteries is that the car's batteries are bigger than the Powerwalls. And there's some efficiency loss. It's more efficient to charge the car when the sun is shining, directly from the panels. However, you certainly can charge the car from the Powerwalls. Just make sure you don't draw the batteries down so far that you don't have enough left to keep the house going until you get sun again the next morning. Charging my car to 200 miles of range, if I go out late in the day, I have plenty of range left when I get home (small island) that I wait until the next day to charge it. I could easily go a week without charging (small island).
If you can get net metering, that's more economical than batteries for nighttime use. But with the high electric rates here, even with the cost of the Powerwalls, my estimated break-even time is around 5 years. And I have power when the grid goes down, though my A/C will not work without the grid. My system can power it, but cannot supply the start-up current. I'm working on getting it converted to soft-start, which would work. If you can live without power during grid outages, and you can get net metering, and cost is an issue, don't bother with batteries. I could afford it, and cannot get net metering, and I like having power when the grid goes down.
There's a cottage behind my house that I rent out. The system I installed for the cottage is 16 panels and just one Powerwall. Because the renter works, and comes home after sundown, the solar powers her A/C during the day and charges the Powerwall, but all her other electric use is in the evening after the sun has gone down, so comes from the single Powerwall. As a result the Powerwall sometimes goes empty and she runs on grid power. Last month she went just a little over the minimum bill, and looks to be on track to run a bit more over the minimum this month. An additional Powerwall would more than take care of that, but would not make financial sense, since I'd be spending $7,000 (the installed cost of the Powerwall) to save probably $5 a month on average. That's a ROI of a tenth of one percent. Tying the two systems together would cost nothing and would save $25 a month (one minimum fee instead of two) but if a future renter were an extreme power hog I could end up paying a lot more. With separate meters and separate bills I can make the renter pay the bill for the cottage.
Basically, if you live in a hot climate with a lot of sun, I think installing solar is a no-brainer. Plus it's a big plus for the environment if your grid is using fossil fuels. (In the Pacific Northwest, where I used to live, it's all hydro. I think Florida is too flat to have any hydro.
ToddRLockwood
Active Member
Does your roof have underlayment (Ice & Water Shield) installed under the shingles? If it does, you're good to go. I had solar installed on my 15-year-old roof with no underlayment (shingles placed directly on top of wood decking), and after only five years I had to have the solar removed so that the roof could be redone—this time with underlayment! The R&R of the solar array cost about $3,500. This wouldn't have happened if the original home developer had used underlayment. It probably saved them all of $500.
Accentcreate
Member
Running AC from the grid is a huge concern vis-a-vis global warming. If you run AC it should be mandatory to only run it from solar or wind powered electricity. Charging the car falls into the same category. I can't comment re USA pricing as we live in Australia and France where we have ample solar systems and no AC. Good insulation and shaded gardens helps a lot.
Great Post Everyone!
Would anyone care to comment on whether it's financially better to buy a system or do the Solar City lease option? I'm sure there is a ton of variation, but just overall curious. Any pro/cons to each that I might not be thinking of? I'm in Southern Arizona, have a M3, and average about $125 per month on electricity.
Thanks!
Would anyone care to comment on whether it's financially better to buy a system or do the Solar City lease option? I'm sure there is a ton of variation, but just overall curious. Any pro/cons to each that I might not be thinking of? I'm in Southern Arizona, have a M3, and average about $125 per month on electricity.
Thanks!
Every calculation I've done or seen has an outright purchase coming out ahead in the long run assuming that you're going to be in the home for a long time.
MorrisonHiker
S 100D 2021.4.12
Exactly. If you can buy it outright and without financing, then there's no interest.
If financing is required, it might be better to "finance" it yourself with a home equity loan instead of financing directly through the solar provider, assuming the interest rate was cheaper.
I installed a 21 panel system after getting 3-4 bids and estimations of how much my roof will generate. With the 30% federal rebate and estimated solar production I estimated it will pay itself off in 8-9 years. With a 20 year lifespan and warranty, this made sense to me and I went with it. Now, about 4.5 years later those assumptions seem about right, looking at about a 9 year payoff, but now that I have a model 3 charging at home, this payoff may be a little sooner than later. I opted to stay on the grid, with no battery. I didn’t want or need that imho.
I went with an installer whose business is also doing roofing work. I liked the idea they’re roofers.
For the first year of the panels, I watched solar production like a hawk and fretted about the payoff timeline and if things were running at peak and all that. Now I’ve relaxed about it. I hose them off from my ladder a few times a year and once a year I get up on the roof with a soapy soft brush and gently clean clean them further. So maintenance is really low overall, a simple hose down should suffice.
We live in SoCal so our summer months see pretty high electricity usage, and so with 21 panels I figure we offset on average about 100-125/ month in electricity.
If it weren’t for the fed and California rebate, system payoff would be more like 13-14 years and perhaps not worth doing so much for the cost savings aspect of it.
If you will need roofing work on your house in the next few years, wait and do it alongside the panels. Or get the work done now alongside panels before the Fed tax rebate goes away (IF it does). If your roof has 5 or more years on it, ask what the installer will charge later on down the road to remove and reinstall your panels while you get roof work done. The place I went with offers it for free if they do the roofing work, or $1k if we hire another roofer when we need to update the roof.
Regardless it was a huge stress at first, since I bought them outright, but I’m very happy to have done it and after a few more years I’ll be in the black with it, and will have offset a fair amount of carbon too. Every sunny state should require new buildings have panels, imho. California is doing that to some extent now. Not sure about others.
If you’re interested in who did my solar, let me know, I have to dig up my referral code. They were on the lower side of all the bids with solar city (now Tesla) having been one of the highest bids.
Lastly, I looked into purchasing outright or leasing and hands down, if you have the cash flow, it makes the most sense to purchase. This installer offered a 18 month same as cash financing, and I paid it off in month 17 so 0% interest and it helped my cash flow. Leasing basically just replaces your electricity utility with a solar utility basically, and you pay them for your wattage received. If you purchase with a loan, don’t forget to factor in the loan/interest costs for me it would’ve extended payoff by about 1.5-2 years with a long term loan.
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For what its worth, I can relay my experience, as an Electrical Contractor (now retired) in Alberta Canada.
Solar
I have 81 panels on my residence, capable of producing a bit over 18 kWs. I installed these in 2012, over two stages, first 45 panels on my garage roof, then 36 on my house roof. This is an Enphase microinverter system, that based on my observation of performance (I monitor production real time through a PLC and Touchscreen setup in my home), and if I had to do it again, I would stay with the microinverter approach with certainty.
- It is safer (240 VAC on the roof max, versus up to 600 VDC for string inverter setups;
- Shut down occurs at the solar panel, where the microinverter is located, on loss of grid power - this is of extreme importance and interest to fire fighters;
- Production is superior in that each panel produces to its greatest ability - shade on one panel affects only that panel, versus string inverter systems where shade on one panel brings down production for the entire string;
Don't interpret this information as marketing or lobbying for Enphase; I am offering it for general knowledge that my microinverter system far out performs string inverter systems for production. This claim is based on comparison with a similar sized string inverter system installed on a local commercial building I'm aware of.
Consumption
Alberta has a terrible electricity marketplace for microgenerators. The system here is 'net billing' versus 'net metering'. With respect to cost of energy, two of the multiple line items on a typical Electricity bill relate to energy consumed from the grid, and energy delivered to the grid. There are a myriad of 'parasitical' costs stacked on to the consumption component, which effectively doubles the cost of the electricity commodity item itself. No parasitical credits apply to energy delivered to the grid. In effect this means, for example, that you pay $.16 per kWh to buy energy (the cost of the commodity plus parasitical charges), and get credited $.08 per kWh for energy delivered to the grid.
If there's one single thing that Governments should do related to renewable resources, it's to make the playing field level between all energy producers. In Alberta, as in some U.S. States, the electricity monopolies play a game of taking generators off line to cause the price of electricity to spike, thereby lining their pockets. There have been court cases about this behavior in California, and Alberta, that I'm aware of. Utilities, is some jurisdictions, perhaps most, are paid on a time-of-use basis, so the generator off line practice is tempting for them.
To be fair to all microgenerators, time of use bi directional meters should be mandatory, with compensation paid to microgenerators based on this.
I submit that the uptake for solar installations would increase markedly, and the 'pay back' time decrease substantially.
I drive a Tesla Model S, and with the size of my system, during the summer months this car is literally powered by the sun. I installed a 70 amp branch circuit, and use a Tesla High Powered Wall Connector for charging the car. I have learned over time, and have implemented through the cars touch screen, a limit of 30 amps to charge the car, so that I don't overwhelm my solar production with other electricity load demands from my house, to prevent from drawing from the grid when charging the car.
I have also installed a number of charging solutions for customers around the city, and have found that a 30 amp, and even a 20 amp 240 volt branch circuit is adequate for over night charging for typical driving needs.
Storage
When the PowerWalls were first introduced, I obtained certified installer status from the Canadian distributor, and secured the two version 1 PowerWalls for installation in my residence. I knew enough then that two would not be enough, and when the remaining four from the number provided for the Canadian marketplace became available, I purchased them. With the six PowerWalls, on a sunny day, they are fully charged by around 2pm (….. could use more PowerWalls……. from purely an ability to charge them up perspective).
Because of the microinverter solar system, the PowerWalls, connected in groups of two to three SolarEdge inverters, are 'AC Coupled'. One SolarEdge inverter is a Master communicating with two slaves over an RS485 loop.
This storage handles my house loads overnight, and when not using A/C 40% capacity is normal after overnight loads, and when A/C is used, 20% capacity is typically left over when the sun comes up again.
This information is provided to offer a perspective, and in my case, I avoid charging my car overnight, to leave the battery storage to handle other typical house loads. Both the Tesla and my hot tub are managed through time programming to allow for solar production to meet those demands. I find this a little more efficient for my purposes.
My view is that good technological advance should not require one to diminish their lifestyle - i.e. throw out the hair dryer and microwave because of inadequate solar production. The paradigm shift for me has been the desire to consider the 'timing' of things. When best to charge the car, when best to heat the hot tub, that kind of thing. The remaining piece to be solved is smart communication between all of these components so production and load matching is done seamlessly, i.e. "if excess solar production - then charge car; if not - don't" that kind of thing. I believe this evolution is coming.
So, in the name of answering several questions that weren't asked (always dangerous), I trust this perspective is of use to the OP and others.
Forgive the lack of icon/name associated with this post. This may in fact be my first one.
Solar
I have 81 panels on my residence, capable of producing a bit over 18 kWs. I installed these in 2012, over two stages, first 45 panels on my garage roof, then 36 on my house roof. This is an Enphase microinverter system, that based on my observation of performance (I monitor production real time through a PLC and Touchscreen setup in my home), and if I had to do it again, I would stay with the microinverter approach with certainty.
- It is safer (240 VAC on the roof max, versus up to 600 VDC for string inverter setups;
- Shut down occurs at the solar panel, where the microinverter is located, on loss of grid power - this is of extreme importance and interest to fire fighters;
- Production is superior in that each panel produces to its greatest ability - shade on one panel affects only that panel, versus string inverter systems where shade on one panel brings down production for the entire string;
Don't interpret this information as marketing or lobbying for Enphase; I am offering it for general knowledge that my microinverter system far out performs string inverter systems for production. This claim is based on comparison with a similar sized string inverter system installed on a local commercial building I'm aware of.
Consumption
Alberta has a terrible electricity marketplace for microgenerators. The system here is 'net billing' versus 'net metering'. With respect to cost of energy, two of the multiple line items on a typical Electricity bill relate to energy consumed from the grid, and energy delivered to the grid. There are a myriad of 'parasitical' costs stacked on to the consumption component, which effectively doubles the cost of the electricity commodity item itself. No parasitical credits apply to energy delivered to the grid. In effect this means, for example, that you pay $.16 per kWh to buy energy (the cost of the commodity plus parasitical charges), and get credited $.08 per kWh for energy delivered to the grid.
If there's one single thing that Governments should do related to renewable resources, it's to make the playing field level between all energy producers. In Alberta, as in some U.S. States, the electricity monopolies play a game of taking generators off line to cause the price of electricity to spike, thereby lining their pockets. There have been court cases about this behavior in California, and Alberta, that I'm aware of. Utilities, is some jurisdictions, perhaps most, are paid on a time-of-use basis, so the generator off line practice is tempting for them.
To be fair to all microgenerators, time of use bi directional meters should be mandatory, with compensation paid to microgenerators based on this.
I submit that the uptake for solar installations would increase markedly, and the 'pay back' time decrease substantially.
I drive a Tesla Model S, and with the size of my system, during the summer months this car is literally powered by the sun. I installed a 70 amp branch circuit, and use a Tesla High Powered Wall Connector for charging the car. I have learned over time, and have implemented through the cars touch screen, a limit of 30 amps to charge the car, so that I don't overwhelm my solar production with other electricity load demands from my house, to prevent from drawing from the grid when charging the car.
I have also installed a number of charging solutions for customers around the city, and have found that a 30 amp, and even a 20 amp 240 volt branch circuit is adequate for over night charging for typical driving needs.
Storage
When the PowerWalls were first introduced, I obtained certified installer status from the Canadian distributor, and secured the two version 1 PowerWalls for installation in my residence. I knew enough then that two would not be enough, and when the remaining four from the number provided for the Canadian marketplace became available, I purchased them. With the six PowerWalls, on a sunny day, they are fully charged by around 2pm (….. could use more PowerWalls……. from purely an ability to charge them up perspective).
Because of the microinverter solar system, the PowerWalls, connected in groups of two to three SolarEdge inverters, are 'AC Coupled'. One SolarEdge inverter is a Master communicating with two slaves over an RS485 loop.
This storage handles my house loads overnight, and when not using A/C 40% capacity is normal after overnight loads, and when A/C is used, 20% capacity is typically left over when the sun comes up again.
This information is provided to offer a perspective, and in my case, I avoid charging my car overnight, to leave the battery storage to handle other typical house loads. Both the Tesla and my hot tub are managed through time programming to allow for solar production to meet those demands. I find this a little more efficient for my purposes.
My view is that good technological advance should not require one to diminish their lifestyle - i.e. throw out the hair dryer and microwave because of inadequate solar production. The paradigm shift for me has been the desire to consider the 'timing' of things. When best to charge the car, when best to heat the hot tub, that kind of thing. The remaining piece to be solved is smart communication between all of these components so production and load matching is done seamlessly, i.e. "if excess solar production - then charge car; if not - don't" that kind of thing. I believe this evolution is coming.
So, in the name of answering several questions that weren't asked (always dangerous), I trust this perspective is of use to the OP and others.
Forgive the lack of icon/name associated with this post. This may in fact be my first one.
Alto Nimbus
Member
I live in S FL and have 33 solar panels for almost 2 years and just added 4 Powerwalls.
My utility is FPL, looks like Orlando uses OUC. Contact your electric company and see what the rules are. What FPL does is not necessarily what OUC will do.
FPL net metering. Good deal, they want to stop it. Tried a big misleading political campaign called Proposition One a few years ago.
FPL Generate over 12 kw, you got to insure FPL for a million bucks
FPL Generate much more then you use they won’t approve your installation
FPL Generate more then you use, FPL will settle up at the end of the year, but only pays the wholesale rate for electricity, much less then you pay.
FPL still have to stay connected to the grid and pay utility fees and franchise charges, about $140 per year.
Installers, they can mess up your roof.
Powerwalls for power outages. Still evaluating, still have bugs in my installation that haven’t worked out, but it’s only a couple of weeks old.
Powerwalls make power at 65 Hz when batteries are full. Won’t run my microwave wave and UPS boxes stay on battery, as if the electricity is out.
LED lights seem to surge, even when Powerwalls not providing power. I’m not sure the cause, may not be Powerwalls but as of now I think it could be.
Change over from grid to batteries not instantaneous. Slight lag causes smart home lights to all turn on.
My utility is FPL, looks like Orlando uses OUC. Contact your electric company and see what the rules are. What FPL does is not necessarily what OUC will do.
FPL net metering. Good deal, they want to stop it. Tried a big misleading political campaign called Proposition One a few years ago.
FPL Generate over 12 kw, you got to insure FPL for a million bucks
FPL Generate much more then you use they won’t approve your installation
FPL Generate more then you use, FPL will settle up at the end of the year, but only pays the wholesale rate for electricity, much less then you pay.
FPL still have to stay connected to the grid and pay utility fees and franchise charges, about $140 per year.
Installers, they can mess up your roof.
Powerwalls for power outages. Still evaluating, still have bugs in my installation that haven’t worked out, but it’s only a couple of weeks old.
Powerwalls make power at 65 Hz when batteries are full. Won’t run my microwave wave and UPS boxes stay on battery, as if the electricity is out.
LED lights seem to surge, even when Powerwalls not providing power. I’m not sure the cause, may not be Powerwalls but as of now I think it could be.
Change over from grid to batteries not instantaneous. Slight lag causes smart home lights to all turn on.
By the way, this is something for people to be aware of. It may not be a good to so overbuild your solar array, depending on how your state or your utility does net metering. In my state (Idaho), there is never a time they will just write you a check for excess you have produced. They just keep track of a number of kWh credits you have stored on your account with Idaho Power, but there is not a way to get paid out in actual money for that. So it is sometimes not advantageous to go over 100% of what you consume. Shooting for 90-some % of your annual consumption cycle is usually good.
My friend overbuilt his system at 125% of their consumption, planning for getting an electric car, and he did, but they don't drive a lot of miles, so he's fretting with what to do as his kWh credits just keep accumulating, and he can't do anything with it.
