SolarCity Isn't Looking So Terrible

[max2k]

My pool is only pulling 300watts/hr and it's a variable pump. 90% of my lights are already LED and we consumed 2400kwh last month(highest ever due to more people in the house so more A/C time), and my lowest was 950kwh the last 12 months. Due to having more people in the house, I actually think we will consume about 30% more this year vs last year. I literally didn't turn on the A/C for 2500 sqft of the house overnight or during the day and now I have to daily because of new people in the house.

All the vendors here are quoting me $$$ over the phone just based on google map and monthly offset(4/5 vendors did this). They provided me with a written proposal with part numbers after they surveyed my roof. SC have not surveyed my roof(requires a 49 dollar refundable deposit) so I'm not seeing them doing out of the ordinary as of yet.

it's your money do as you wish. All we're saying is that with simple education (the book), analysis (PvWatts + your yearly consumption) and some thinking you most likely will be able to save good amount of money. At least several ppl did so.

More ppl in the house would definitely drive electricity consumption up. My pool pump runs at 1200 rpm, consumes something in 100-150W range and it does so only for 10 hrs/day.

One more thing- from this forum I heard FL has one of the lowest electricity rates in the country. Your yearly consumption looks like about 30% more than mine so my oversized system would be oversized for you at about 9 kW. Since you're saying at 11kW it is going to be barely enough it means your location is less optimal. PVWatts can give you an idea what to expect. What I'm saying you need to do cost analysis and see if you ever going to recover money you're about to spend on this project. If electricity is relatively cheap and location is not optimal I'd take a very long and hard look at the whole thing. In my case again with perfect orientation and in the sunny CA and with our high electricity rates and with me doing the installation myself I'm still looking at 5 years ROI. Remove any of the variables and I wouldn't do it. Think about maintenance too- with many years before break even point things will break putting that point even further into the future.

[Singuy]

it's your money do as you wish. All we're saying is that with simple education (the book), analysis (PvWatts + your yearly consumption) and some thinking you most likely will be able to save good amount of money. At least several ppl did so.

More ppl in the house would definitely drive electricity consumption up. My pool pump runs at 1200 rpm, consumes something in 100-150W range and it does so only for 10 hrs/day.

One more thing- from this forum I heard FL has one of the lowest electricity rates in the country. Your yearly consumption looks like about 30% more than mine so my oversized system would be oversized for you at about 9 kW. Since you're saying at 11kW it is going to be barely enough it means your location is less optimal. PVWatts can give you an idea what to expect. What I'm saying you need to do cost analysis and see if you ever going to recover money you're about to spend on this project. If electricity is relatively cheap and location is not optimal I'd take a very long and hard look at the whole thing. In my case again with perfect orientation and in the sunny CA and with our high electricity rates and with me doing the installation myself I'm still looking at 5 years ROI. Remove any of the variables and I wouldn't do it. Think about maintenance too- with many years before break even point things will break putting that point even further into the future.

Good point, my ROI is around 9-10 years. Not extremely optimal vs somewhere like Hawaii or where you live. I wish my ROI is 5 years. I should expect to save $2500-3000/year after spending 22-30k after tax credit. This is no where near 5 years. But it's still a 10% return from 10 years on, or 5% return on my money after 20 years from day one.

In FL, we get rain constantly in the summer while you guys get cool dry sunny days for way more months than FL.

[max2k]

Good point, my ROI is around 9-10 years. Not extremely optimal vs somewhere like Hawaii or where you live. I wish my ROI is 5 years. I should expect to save $2500-3000/year after spending 22-30k after tax credit. This is no where near 5 years. But it's still a 10% return from 10 years on, or 5% return on my money after 20 years from day one.

In FL, we get rain constantly in the summer while you guys get cool dry sunny days for way more months than FL.

I'm not sure you ever going to see that- 20 years is very long time for power electronics and with ever changing solar landscape I wouldn't put too much faith into multi- year warranties companies offer. Most likely you'll be doing repairs at your own expense. If I were you I'd simply put your numbers on paper to see if they work. If you need help you can always ask here but you need to give us some data to work off: your annual electric bill, your yearly consumption in kWh, PVWatts predicted production in kWh based on your location and orientation. Having these numbers you could see if it makes sense for you or not. Basically you need to confirm that $2,500-$3,000 of savings you got there. I have a feeling it's too high as my own savings are around 2k and while I have smaller bill/system my prices are significantly higher.

[Singuy]

I'm not sure you ever going to see that- 20 years is very long time for power electronics and with ever changing solar landscape I wouldn't put too much faith into multi- year warranties companies offer. Most likely you'll be doing repairs at your own expense. If I were you I'd simply put your numbers on paper to see if they work. If you need help you can always ask here but you need to give us some data to work off: your annual electric bill, your yearly consumption in kWh, PVWatts predicted production in kWh based on your location and orientation. Having these numbers you could see if it makes sense for you or not. Basically you need to confirm that $2,500-$3,000 of savings you got there. I have a feeling it's too high as my own savings are around 2k and while I have smaller bill/system my prices are significantly higher.

PVWatts is telling me a savings of 2118/year using premium panels with default loss. Definitely makes the mono panels a harder buy.

[J.P.M.]

PVWatts is telling me a savings of 2118/year using premium panels with default loss. Definitely makes the mono panels a harder buy.

PVWatts does a fair job of long term estimates of system output. I've found its accuracy when estimating annual savings is not that good based on where it gets its utility rates and the required user input as to where those rates come from. Best to educate yourself on what and how your POCO charges you. Part of the required education if you want to do it right.

Also, PVWatts uses a system loss parameter of 14%. Many users have found that produces a somewhat consistent underestimate of long term average system output compared to what other models (NREL's SAM for example) show. Using 10% in PVWatts rather than the default 14 % commonly gets closer to the SAM long term average estimate. If I use ~ 7 %, I get close to the number SAM comes up with for annual output.

[J.P.M.]

I'm not sure you ever going to see that- 20 years is very long time for power electronics and with ever changing solar landscape I wouldn't put too much faith into multi- year warranties companies offer. Most likely you'll be doing repairs at your own expense. If I were you I'd simply put your numbers on paper to see if they work. If you need help you can always ask here but you need to give us some data to work off: your annual electric bill, your yearly consumption in kWh, PVWatts predicted production in kWh based on your location and orientation. Having these numbers you could see if it makes sense for you or not. Basically you need to confirm that $2,500-$3,000 of savings you got there. I have a feeling it's too high as my own savings are around 2k and while I have smaller bill/system my prices are significantly higher.

The OP may have a lower average per kWh rate than you, but a lot higher usage. Still, as you write, it's all a guess and an exercise in futility without numbers.

One other thing: The idea of alternate investment vehicles is often looked at, but more often overlooked. Say you've got $30K in hand to invest. You can either buy $30K/.7 = 42.9K worth of PV equipment or buy, say, a mutual bond fund that pays a long term ave. of, again, say, 5%. Using reasonable but eyes wide open assumptions about the future, at the end of 20 years, which alternative will be farther ahead ? Other alternate investments can be looked at the same way, Corp. Bonds. REITS, property, precious metals, stocks, start a business. The list goes on.

[max2k]

The OP may have a lower average per kWh rate than you, but a lot higher usage. Still, as you write, it's all a guess and an exercise in futility without numbers.

One other thing: The idea of alternate investment vehicles is often looked at, but more often overlooked. Say you've got $30K in hand to invest. You can either buy $30K/.7 = 42.9K worth of PV equipment or buy, say, a mutual bond fund that pays a long term ave. of, again, say, 5%. Using reasonable but eyes wide open assumptions about the future, at the end of 20 years, which alternative will be farther ahead ? Other alternate investments can be looked at the same way, Corp. Bonds. REITS, property, precious metals, stocks, start a business. The list goes on.

That crossed my mind and think even 5 year break even point is barely passable. If I'm not mistaken 5 years is standard accounting amortization period so whatever I'll have left from my system after 5 years will be pretty much scrap. When considering using installer's services it was more like 8-9 years even though I'm perfectly capable of fixing it myself so there was no need for extended warranties or maintenance expenses. At 8-9 years I was not going to do it. In comparison my pool pump paid for itself within 8 months IIRC and LEDs- in 3 or 4 months due to deep sales Home Depot was having on Cree brand.

[Singuy]

The OP may have a lower average per kWh rate than you, but a lot higher usage. Still, as you write, it's all a guess and an exercise in futility without numbers.

One other thing: The idea of alternate investment vehicles is often looked at, but more often overlooked. Say you've got $30K in hand to invest. You can either buy $30K/.7 = 42.9K worth of PV equipment or buy, say, a mutual bond fund that pays a long term ave. of, again, say, 5%. Using reasonable but eyes wide open assumptions about the future, at the end of 20 years, which alternative will be farther ahead ? Other alternate investments can be looked at the same way, Corp. Bonds. REITS, property, precious metals, stocks, start a business. The list goes on.

This is how I am looking at it atm, solar panels as an alternative investment. The payout is post tax money saved on mandatory spending such as electric bill. If I can get a 5% from CDs(which I can't right now), I will only end up with a 3% return after taxes. Same with dividends paid out via bonds/reits, in which I only get to keep 1/3 of the return due to taxes. The return from solar is actually post tax savings..meaning I have to make 3k just to pay 2k/year on electricity.

Another way to think of this is, the electric company is charging me a 8-9% interest since I refuse to pay off 30k..and will continue to charge me 8-9%% until I die, or until that 30k is paid off.

At the end of the day, as long as I get a problem free system for 20 years, then this investment is still worth it.

[max2k]

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At the end of the day, as long as I get a problem free system for 20 years, then this investment is still worth it.

please be realistic- 7 may be 10 years tops then you'd either need to learn how to fix simple problems yourself or you'll be paying someone every 2-3 years after. These things don't last forever. I recently replaced much simpler device- AC breaker in my service panel. Think about it- what possibly could go wrong with a breaker? Well, bad contact to the main bus bar, thing got hot and literally melted its contact with the bar. Why it decided to die this year after probably 15 years in service is anyone guess. For the record, I haven't touched the thing as I'm using existing subpanel to backfeed solar.

BTW, do you know your service panel rating? Mine is 200A and backfeeding it with 32A AC current is at the max end of the range of doing it. 11kW system will produce 46A current which would require 60A breakers. So you're probably going to have 'line side connection'.

[Singuy]

please be realistic- 7 may be 10 years tops then you'd either need to learn how to fix simple problems yourself or you'll be paying someone every 2-3 years after. These things don't last forever. I recently replaced much simpler device- AC breaker in my service panel. Think about it- what possibly could go wrong with a breaker? Well, bad contact to the main bus bar, thing got hot and literally melted its contact with the bar. Why it decided to die this year after probably 15 years in service is anyone guess. For the record, I haven't touched the thing as I'm using existing subpanel to backfeed solar.

BTW, do you know your service panel rating? Mine is 200A and backfeeding it with 32A AC current is at the max end of the range of doing it. 11kW system will produce 46A current which would require 60A breakers. So you're probably going to have 'line side connection'.

Almost seems like you don't recommend solar at least for me. I am not interested in fixing any electrical issues myself in the future. So if you are saying that these systems crap out in 7-10 years and require repairs every 2-3 years afterwards, then it's probably not worth getting unless I'm interested in an electrical engineering degree.

[J.P.M.]

This is how I am looking at it atm, solar panels as an alternative investment. The payout is post tax money saved on mandatory spending such as electric bill. If I can get a 5% from CDs(which I can't right now), I will only end up with a 3% return after taxes. Same with dividends paid out via bonds/reits, in which I only get to keep 1/3 of the return due to taxes. The return from solar is actually post tax savings..meaning I have to make 3k just to pay 2k/year on electricity.

Another way to think of this is, the electric company is charging me a 8-9% interest since I refuse to pay off 30k..and will continue to charge me 8-9%% until I die, or until that 30k is paid off.

At the end of the day, as long as I get a problem free system for 20 years, then this investment is still worth it.

But at the end of the same day, the assumption on a lot of the alternative investments is that all of the original principal will be returned to you. I'm not willing to make that same assumption about a PV system, or that it's trouble free or completely maintenance free. I don't need to house down a corporate bond for one, small example. No one knows what a PV system on a roof will be worth in, say, 20 years, but if all the derelict solar water heaters I see are any indication, I'd guess not much, and maybe even adding negative equity to a property as a nuisance in 20 years, but certainly not worth 100 % of the original input value as a corporate bond @ 5 % will probably be.

Unless someone is a serious high roller, and given the tax structure we have in the U.S., I kind of doubt most are paying 30% of their income in taxes. If so, they'd be in tax free MUNI's etc., and probably have bean counters with enough brains to lower their tax bill.

To play the alternate investment game, and do it with some reasonable hope of meaningful, results requires some knowledge of the time value of money and a small bit of financial savvy (but not much) beyond the simplistic payback method. There are too many variables that may/may not apply to be able to justify the moron method.

But the same can be said of any long term investment that requires tying up considerable assets for a long time. I'd respectfully suggest no one with any assets would seriously consider CD's as a viable alternate investment for a large sum. A good way to minimize or have negative return on investment maybe. But not my money/life/whatever.

Seems to me most folks find it easier to bitch and moan and then throw less than cost effective PV at self inflicted high electric bills rather than taking a few hours and finding what is cost effective and then spending a few more hours understanding the basics of financial analysis. But, again, not by business/money/life/whatever.

[max2k]

Almost seems like you don't recommend solar at least for me. I am not interested in fixing any electrical issues myself in the future. So if you are saying that these systems crap out in 7-10 years and require repairs every 2-3 years afterwards, then it's probably not worth getting unless I'm interested in an electrical engineering degree.

this forum is known for its 'anti- solar' attitude . In reality you might find the information given here is not 'for' nor 'against' solar in general it is more sobering so to speak. Any complex thing breaks- try to find 20 year old TV and check what works and what not. Some make it but majority- don't. Panels themselves seem to be the longest lasting component so far but the rest- just normal residential electric equipment life expectation, you just need account for that.

It would help to make this thread more concrete if you could share your yearly consumption in kWh and the output in kWh PVWatts produced for your location/orientation. May be there's not much savings there to begin with.

[Singuy]

The assumption is not what the panels will be worth in 20 years, but I should have offset enough electric cost that should double what the original panel have cost. If in 20 years, I can save 40k in electricity from a 20k panel, then I could care less how much residual value the panels have.

But yeah I already have Muni bonds and plenty of index funds...but the market isn't exactly under valued and interest rate can only climb which makes even bonds risky.

So are there a lot of people who have gone solar beyond 10 years having a lot of electrical problems with them? Let me know because I'm just assuming I should have a problem free experience besides needing to change the inverter in 10-15 years.

[max2k]

The assumption is not what the panels will be worth in 20 years, but I should have offset enough electric cost that should double what the original panel have cost. If in 20 years, I can save 40k in electricity from a 20k panel, then I could care less how much residual value the panels have.

But yeah I already have Muni bonds and plenty of index funds...but the market isn't exactly under valued and interest rate can only climb which makes even bonds risky.

So are there a lot of people who have gone solar beyond 10 years having a lot of electrical problems with them? Let me know because I'm just assuming I should have a problem free experience besides needing to change the inverter in 10-15 years.

OK, IMO only good quality string inverter should last 10 years. If you replace it with brand new one at that point you'd 'reset' the timer back to 0. Of course panels will still be 10 yo but they don't look like limiting factor here. String inverters require no shading or at least shading you can live with.

Besides string inverters there are 2 other popular setups:

- optimizers + inverter (Solar Edge). This is good if you have shade 'walking' across your array through a day. Reliability wise I have no idea but my gut feeling says it is 8-10 years and then even if you replace inverter optimizers would still remain on the roof.

- microinverters. I think they will require regular trips to the roof / replacement after the first 5 years or even sooner. Again no stats to back this up.

[Singuy]

Hmmm..why would the timer set back to zero when replacing an inverter is a fraction of the cost of a freshly installed solar system?

i barely have any shading besides perhaps pes and vents that may cast a shadow some point in the day.

Right now I am really considering polys just based on the cost alone. Since you guys are saying my Roi expectations are too high.