Most people have a limited number of panel placement options. Not all have the luxury of picking between roofs facing south, east, and west. And while one can play with placements using software, I highly doubt the software accounts for any local codes that can dictate panel placement, conduits needed to be run to the electrical panel, any electrical panel updates, permitting fees, etc. that can add up. A handful of bids from contractors will be more practical for installation cost estimates. One can then plug the cost into a financial calculator (or use the estimates provided by the contractor) to calculate break even point using various scenarios. By getting multiple bids, one can easily see who could lying. 
Another thing that hasn’t been mentioned. In our state (for a while…not sure if still true), lower income folks could get a huge price break on leasing or owning. We have friends who honestly didn’t pay anything to lease their solar panels because their income was below whatever threshold was in place when they went solar. I’m not sure where that subsidy came from.
Some of you have mentioned $18,000 or so to have panels installed. Our cost this January was quite a bit higher than that…but that doesn’t take into consideration the tax rebate we will get in 2023.
I haven’t read the whole thread, but I expect the cost to be highly dependent on the amount of power to be generated.
Yes, the link in my earlier post lists an average price of $4.6/Watt AC in Santa Clara County, for both big and small residential systems (most other locations show larger difference in $/Watt between large and small). So one might estimate a 3kW AC system as often costing ~$14k prior to tax benefits and other reductions or a 6kW AC system as costing ~$28k prior to deductions.
In my town, there were ~1500 installs over the past year. The median overall install cost was $25,500. The median by system size is listed below. Bigger systems have a higher net cost, but lower cost/watt. A rough estimation is ~ $4.6/watt for small systems or ~$4/watt for big systems
Median Cost of Solar Purchased in Past Year, in My Town
2KW to 3KW – $14k
3KW to 4KW – $16k
4KW to 5KW – $19k
5KW to 6KW – $23k
6KW to 8kW – $28k
8kW to 10kW – $35k
10kW to 15kW – $47k
However, within any of these size groups there is a wide variation of install prices. For example, among the 4KW to 5kW system size group, the distribution was:
4KW to 5KW Systems Purchased in Past Year, in My Town
10th percentile – $13k
25th percentile – $16.5k
Median - $19k
75th percentile – $23k
90th percentile – $30k
The point was there are many factors that influence payback time period. Persons not having to the luxury to choose the optimal solar panel placement, including south/east/west placement or shading issues contributes, as does variable installation costs.
A consumer using tools like the ones that were linked would enter the net installation cost, rather than have the tool try to predict their installation cost. However, the tool gives the option to calculate cost and estimated return for installers, including entering cost for labor, cost for equipment including conduits, cost for permits and environmental studies, etc.
Note that installation costs can vary for reasons other than installers’ prices. For example, if the house needs a main panel upgrade or longer or more complicated wiring runs, that can add to the cost.
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Lol. You overestimate an average consumer. Not everyone is obsessed with squeezing every penny out of the project. An average consumer will not bother with downloading some software and doing calculations. Since one still needs to get several bids, as any prudent homeowner should do, one might as well see what the installers have to say. A more practical solution for many.
It’s not an either or solution. Nobody said you should not get bids from multiple installers or you should ignore what the installer says. However, that does not mean one should take everything the installer says at face value and assume the potential for the installer to make what may be a $20k sale does not lead to any biases or favorable assumptions in their calculations.
The more simple PVWatts tool that was linked in the first post is intended for consumers. If you have the numbers and choose to skip drawing specific panel placement on satellite of roof, it may take under 1 minute to fill out and get results… I found the tool useful, as have some other solar owners I’ve known. If you do not find it useful, feel free to not use it.
It isn’t that it is not useful. In the end, calculations are calculations, and bids are bids. A minimum of three, better 3-5, to weed out those goons who like to overcharge. 
ETA: if the houses are all cookie cutter built at the same time, then an estimator based on what the neighbors did works great! If the houses are like in my neighborhood, where everything is different and built at different times, it unlikely that my neighbors’ estimates will be much helpful.
I was quoted a system price of $5-8/W from a few installers for a large system about 13 years ago. I’m a little surprised that price hasn’t come down as much as I thought it would.
While there is variability of costs in different homes for a variety of reasons, the DOE/NREL estimates that installation itself typically only accounts for ~7% of the total cost for typical installs (in 2021). Being such a small fraction of the total net cost for solar typically leads to other factors having a much larger influence in variation in total net cost than differences in housing style among neighbors (not counting needing to replace roof as part of install). For example, one should not expect huge differences on overall cost because one house is 2 stories and other is 1 stories, or one house has a different gable style roof and the other hip style roof. These house style differences can and often do have an influence on install cost, but other factors usually dominate the overall net cost. The specific breakdown in the DOE/NREL report was:
35% – Panels, Inverter, and other Hardware
21% – Overhead and Profit
18% – Customer Acquisition
9% – Supply Chain
8% – Permits and Inspection
7% – Installation
Of course the specific breakdown varies wildly among different specific companies, locations, and installs Some types of solar panels, inverters, and other hardware cost far more than others. Some customers choose extras like a battery. Some companies have a far higher profit margin than others. Some companies spend far more on customer acquisition than others…
It’s certainly not mandatory to look up cost of solar installs in your area in the database, but I personally like having that option available to me and found it useful. I’d make a similar comment for buying a car, house, or nearly any 5+ figure material purchase. In addition to getting a sense of what prices to expect and which installers tend to have higher/lower prices, I used the referenced CA solar install cost database to negotiate prices. I was able to show what the solar installer who quoted me had charged for similarly sized other installs in my town. The installer I selected responded by sharing the guidelines their company uses to price projects and how much flexibility they have in setting prices for particular install (it’s a lot, and he described my area as a “cash cow”).
Their pricing guidelines were primarily based on number of panels and specific type of panel, likely for simplicity. They also had some thresholds with sharp changes in prices that I found surprising. For example, there was relatively little $/watt difference when increasing from 8 to 9 panels or 9 to 10 panels, but increasing from 10 to 11 panels led to a sharp step decrease in $/watt. Perhaps this relates to incentives from the panel manufacturer to sell their (at the time) newer panels. After seeing the thresholds, I added an extra panel, so I crossed a threshold.
The attached graphs show the average $/W for solar installs in CA over time. There was a sharp decrease for many years, then prices started to level out around 2018, and more recently costs have increased. Part of this change in trend may relate to the 2018 changes in international trade policies/tariffs, and part may relate to COVID supply chain disruptions. Note that the discontinuity in 2015 relates to different sample groups – pre-NEM installs and post-NEM installs.
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I was shocked by the quick payback times for a solar installation that were quoted here. Then I looked up the Bay Area electric rates — 31 cents per kWh? Wow.
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I was shocked by the quick payback times for a solar installation that were quoted here. Then I looked up the Bay Area electric rates — 31 cents per kWh? Wow.
There are many contributing factors for the lower payback period in CA compared to other areas. One is tha CA NEM 2.0 is very favorable for solar customers. One independent review found that solar customers in my area only pay the power company 9% of how much it costs for the power company to serve the solar customers, with paying retail rates for solar electric generation, letting the solar credits rollover from one month to the next and having little remaining fees/costs.
With the power company losing so much on solar customers, they need to increase rates for non-solar customers. This leads to further increasing rates and further customers choosing to switch to solar, sort of like a death spiral. NEM 3.0 goes in to effect on April 14th (for new solar customers), which provides a more sustainable model that is not as friendly to persons with solar panels. Some estimates suggest NEM 3.0 will nearly double payback period over NEM 2.0.
Electric rates are also high due the moderate climate with less A/C and heating/cooling usage per line cost, a statewide emphasis on clean power, wildfire mitigation, a high rate of underground cables, generally having higher fees/costs than other areas, etc. The end result is summer electric rates like below.
Plan 1: $0.80 → $0.80/kWh peak $0.47 → $0.47/kWH off-peak, $0.36 → $0.36 /kWh so-peak
Plan 2: $0.72 → $0.84/kWh peak, $0.40 → $0.52/kWH off-peak, $0.26 → $0.37/kWh so-peak
Plan 3: $0.56 → $0.67/kWh peak, $0.45 → $0.57/kWH off-peak, $0.35 → $0.46/kWh so-peak
Another factor is the weather. My area only averages ~10 inches of rain per year and gets no snow. Number of sunny days is also well above average – triple the sunny days of various northeast cities, like NYC. This is a great climate for solar generation.
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We use Enphase also. So…we have been checking it for the last two days. It’s actually fun to see how much we have generated, and how much we actually have been using. We are surprised to see how little power we actually use.
Of course, this will change in the summer when we have AC running on hot days.
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Frustrating experience getting solar installed. We’d actually signed an agreement two years ago with Tesla and they just kind of stopped.
We recently signed with another company. I interviewed two local companies that have good reputations and have recently done work for people I know. One was a lot less expensive than the other – the more expensive one was surprised at the price. In the two or three weeks since signing, I find I have to prod them at each step. Currently working on getting their electrical folks to come over and do whatever the next steps are.
^^That’s frustrating. We gave up on Tesla shakes right away when the roofer who is Tesla roof certified told us that the code will not let us get what we needed because the code requires the “active” shingles to be placed so far away from any ridges and skylights that 90% of our roof would be dummy shakes. No thanks. We heard horror stories about their panel guys so got bids elsewhere. The company we used was excellent. Anyone in the greatest Seattle area looking for solar installer, please feel free to PM me.
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Having a quality solar installer is critically important. The biggest risk in a solar installation is that the roof develops leaks years later, because solar panels have to be bolted to the roof (and those bolts have to penetrate the roof). It’s very rare, though (I have had solar for about 13 years and never had a problem).
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We are happy with the company we used as well. It did take some shopping around. We did not go with the company lots of others used that advertised “no cost” solar panels, because that is BS. You either lease or buy…and there is a cost to both but they don’t really tell you that until they are in your house.
So far 
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Yes, the installer is important, and there is a wide variation of qualities. Based on Nextdoor comments, one of the most popular installers in my area seems to be Sunrun. I guess people trust them because they go through Costco or trust the many sales agents making posts on Nextdoor. Their ratings on review sites are abysmal, often with >80% giving the minimum score. There are reviews that mention spending >$50k due to damaged roof, leaving panels in driveway for months with no installation, being locked in to losing money contract due to cost (per month lease) being more than saving from solar generation. near zero post-install support, etc. It sounds like an awful company, yet the still get plenty of business and some people seem happy to refer them. One should also keep in mind that it’s common for installers to give $1000+ for referrals that lead to a purchase, This leads to more conflicting motivations for giving referrals than with most other services.
I expect one contributing factor to this negative Sunrun outcome result is they subcontract out installation at a low cost to persons who are sometimes not high quality and spend relatively little money on support beyond this. However, even installers that do not subcontract out, have great reputations, great reviews, and a history of high quality installations with good support may not be a safe bet because a large portion of installers are going to close prior to the what may be 20 year lifetime. This happened to one of the of the 2 most frequently recommend installers on my Nextdoor, at the time I got solar. It was a family owned company whose license was suspended after the founder failed to pay a civil judgement, relating to a domestic issue from years earlier. Other installers have stepped in and offered support, but often at a high fee for service issues and with limitations on what parts/issues they are capable of fixing.
I’m satisfied with the company I used overall. The installation was extremely fast and seemingly high quality. I did find one issue years after install. My overall solar generation was well above contract specifications and met my original expectations when purchasing solar. However, it was consistently 5-10% less than previous years, on clear sky days at similar point in year. My installer worked with the manufacturer and resolved the issue quickly by updating FW, at no charge. After the fix, solar generation returned back to previous year levels. I am not as satisfied with the monitoring software. At the time of my install, the monitoring software was outstanding – extraordinarily detailed information on each specific panel, with dozens of possible graphs over time. Now they only offer the detailed monitoring for installers/support, and dumbed down the consumer monitoring to only show combined production from all panels and not much else. I suppose this helps with getting fewer support requests when nothing is wrong, but I’d at least like to be able to monitor the output of specific panels.
We get exactly $0 for referrals. Making that clear because the poster above implies that referrals are oftentimes bought with incentives. I wouldn’t work with or buy any products from a company that buys referrals. Period. No matter how great the work might be.
Re: roofs. If you are considering solar and need a new roof, investigate standing seam metal roofing. These are often called “solar ready.” Solar panels clip onto the ribs of these roofs using a system of rails. Not a single hole goes through the roof, and no one needs to have access to attic space. Another advantage: birds will not try to make nests under the panels because the metal is too slippery to keep the nests on it.
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