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The article emphasizes that the declining price is due mostly to peripherals & installation rather than any scientific breakthroughs of the solar panels themsel

by jasode 10y ago

The article emphasizes that the declining price is due mostly to peripherals & installation rather than any scientific breakthroughs of the solar panels themselves. The following quote is key: >"This means that the decline in installed cost observed since 2012 was largely caused by a decline in the cost of the inverters that convert the DC power produced by solar panels to AC power for the grid and other “soft” costs such as customer acquisition, system design, installation, and permitting." On another note, calculating the payback of residential solar panels is tricky because many online calculators don't consider: - inverters failing and needing to be replaced (~10 years?) - bank of backup batteries need to be replaced (~10 years?) - significant increased labor costs of replacing the roof or repair roof leaks (roofers must spend extra time unmounting all panels before replacing shingles or tiles.) - paying a service to clean the panels if the house is in a dusty climate and the homeowner doesn't want to climb on the roof and do it himself One can lump all those negative costs into one bucket called "ongoing maintenance" to simplify things but nevertheless, it doesn't seem like many ROI calculators properly account for them. (That said, some people pay the premium for solar panels to gain power autonomy which overrides any over-optimistic estimates of installation payback.)

crdoconnor 10y ago
>The article emphasizes that the declining price is due mostly to peripherals & installation rather than any efficiency breakthroughs of the solar panels themselves. Over the last few years racks, mounts, wiring, inverters and labor have made up ~60% of the cost. Plus, Obama started slapping ~30% tariffs on the cheapest imported solar panels.
- Godel_unicode 10y ago
  Not sure why you're being downvoted, I assume the ~20℅ anti-subsidy rates plus the individual anti-dumping rate referenced in the below article are what you're referring to? http://www.bloomberg.com/news/articles/2015-07-09/u-s-imposes-dumping-duties-on-imports-of-chinese-solar-goods http://www.bloomberg.com/news/articles/2015-07-09/u-s-impose...
  - crdoconnor 10y ago
    Yep that's the one. I read the state department report too. The 'disguised subsidies' they called China out on included 'advertising' the solar companies' existence on local government websites. Clearly they didn't expect anybody to actually read that.
- jakub_h 10y ago
  In the US, I'd image tariffs on panels having a much lower influence then elsewhere in the world. Even if panels were completely free in the US, a US-based residential solar system is going to be more expensive to install than even European ones (including European panel costs).
pjc50 10y ago
Stick with a grid-tie system for the time being, especially if you can get the right feed-in tariffs. I don't really see the case for domestic storage systems yet.
- RobertoG 10y ago
  I suppose you mean the 'economic case'. Some people is doing it for other reasons, as is frequently the case for early adopters of any technology.
- brightball 10y ago
  The biggest market for domestic storage is people who would want an emergency generator anyway. You get most of the same benefit for a lower cost with a Powerwall (if the expectation is temporary outage tolerance). IMO that's the best comparison for domestic storage though.
  - maxerickson 10y ago
    A Powerwall doesn't store enough energy to be worth much in a real emergency. It's going to be nice to keep your refrigerator running during a short power outage, but it won't provide days or weeks of power the way an inexpensive generator can (for example http://www.homedepot.com/p/Generac-11-000-Watt-Air-Cooled-Automatic-Standby-Generator-with-200-Amp-SE-Rated-Transfer-Switch-6438/204006867 http://www.homedepot.com/p/Generac-11-000-Watt-Air-Cooled-Au... ). Sure, you have to either trust that nat gas is available or deal with fuel, but a propane tank isn't obscenely expensive considering that it bumps your backup from hours to days/weeks.
    - erikpukinskis 10y ago
      I don't understand your argument. A Powerwall, if it can get you through the trough, means in an emergency you have the same amount of power you'd have in a non-emergency.
      - maxerickson 10y ago
Kenji 10y ago
Not only that, but it's not uncommon for panels to crack. Kids throwing stones or balls, weather-related, etc. Replacing the glass is often difficult or expensive. Alternatively, you can fix it but that will often reduce the clarity and thus the generated electricity.
- toomuchtodo 10y ago
  Panels are sturdy enough to withstand 4 inch hail and hurricane winds if properly mounted to a roof or concrete ground support.
sandworm101 10y ago
You have a good point re roof penetrations. There are too many cowboy solar installers casually drilling holes thinking a blob of silicon is enough to seal out the rain. Also, when you eventually want to replace the roof handling and reinstalling the panel probably doubles the labour costs.
- jandrese 10y ago
  My thought is that you would install the solar panels when you're replacing the roof. Put 30 year panels on a 30 year roof. 30 years later you get to do it all over again, but at least you're not removing and reinstalling the panels when you replace the roof.
  - sandworm101 10y ago
    Even without solar, few last 30 years without major repairs where I am (pacific northwest). There are lots of things to consider. Some/most solar installs don't take debris into account, creating dams that can send water places it shouldn't be, like up and under shingles. Not an issue in the desert but in rain forest it is a big deal. And the number of penetrations ... I've seen people put dozens of screws through what used to be a good roof. They cannot all be perfect.
    - ashark 10y ago
      Around here (midwest) hail or wind usually knocks out composite roofing in 10-15 years—much less if you're unlucky. There's little point in springing for the "50 year" composites and similar. I guess the solar panels would protect the roof a bit, but I'd expect a bad hail storm to be bad news for those, too.
- secabeen 10y ago
  This was a reason I put solar in after installing a standing seam metal roof. The roof will last 50+ years, and the solar just clamps onto the seams. Only penetration is for the cables to the inverter.
tsjackson 10y ago
Inverter failure is real, but the industry standard has risen to 12 years for string inverters, and 20-25 for micros. Even for string inverters, most of the residential/small commercial market has moved to using optimizers for voltage regulation, which means the inverter itself is a lot lighter weight/cheaper. Backup batteries are still relatively rare, as they should be - they are fairly expensive as backup power. Most systems remain grid tied. Smaller systems don't require retail net metering for a solid payback, since almost all of the energy is used as it is produced. Roof repair is again, real, but not as likely as you might think. Asphalt shingles under an array are protected from wind, and even more importantly, heat. They degrade at half the rate of the rest of the roof. Assuming 12-15 years for roof replacement, you will hit the module warrantied life of ~25 years before you need to replace the roof underneath the array. Cleaning the panels really only comes into play when the pitch of the roof is relatively shallow (3 on 12 or shallower). Otherwise rain will clean them fairly well. A lot of people won't have any trouble walking such a shallow pitched roof, and will simply hose the panels off once in a while. Also, in general, the price of modules per watt is about half of what it was 5 years ago. Peripherals are a major component of the improved economics, but module prices themselves have mattered just as much.
ChuckMcM 10y ago
> On another note, calculating the payback of > residential solar panels is tricky because many > online calculators don't consider (stuff...) Sometimes they do, we installed Solar in 2003, we replaced a failed inverter in 2016. At the time we installed the system we got a new roof with asphalt shingles (50 year roof) which both helped the roof load (they were lighter than the previous wood shake) and was a time period longer than the payback period for our panels.

by jasode 10y ago

crdoconnor 10y ago

>The article emphasizes that the declining price is due mostly to peripherals & installation rather than any efficiency breakthroughs of the solar panels themselves. Over the last few years racks, mounts, wiring, inverters and labor have made up ~60% of the cost. Plus, Obama started slapping ~30% tariffs on the cheapest imported solar panels.

Godel_unicode 10y ago
Not sure why you're being downvoted, I assume the ~20℅ anti-subsidy rates plus the individual anti-dumping rate referenced in the below article are what you're referring to? http://www.bloomberg.com/news/articles/2015-07-09/u-s-imposes-dumping-duties-on-imports-of-chinese-solar-goods http://www.bloomberg.com/news/articles/2015-07-09/u-s-impose...
- crdoconnor 10y ago
  Yep that's the one. I read the state department report too. The 'disguised subsidies' they called China out on included 'advertising' the solar companies' existence on local government websites. Clearly they didn't expect anybody to actually read that.
jakub_h 10y ago
In the US, I'd image tariffs on panels having a much lower influence then elsewhere in the world. Even if panels were completely free in the US, a US-based residential solar system is going to be more expensive to install than even European ones (including European panel costs).

pjc50 10y ago

Stick with a grid-tie system for the time being, especially if you can get the right feed-in tariffs. I don't really see the case for domestic storage systems yet.

RobertoG 10y ago
I suppose you mean the 'economic case'. Some people is doing it for other reasons, as is frequently the case for early adopters of any technology.
brightball 10y ago
The biggest market for domestic storage is people who would want an emergency generator anyway. You get most of the same benefit for a lower cost with a Powerwall (if the expectation is temporary outage tolerance). IMO that's the best comparison for domestic storage though.
- maxerickson 10y ago
  A Powerwall doesn't store enough energy to be worth much in a real emergency. It's going to be nice to keep your refrigerator running during a short power outage, but it won't provide days or weeks of power the way an inexpensive generator can (for example http://www.homedepot.com/p/Generac-11-000-Watt-Air-Cooled-Automatic-Standby-Generator-with-200-Amp-SE-Rated-Transfer-Switch-6438/204006867 http://www.homedepot.com/p/Generac-11-000-Watt-Air-Cooled-Au... ). Sure, you have to either trust that nat gas is available or deal with fuel, but a propane tank isn't obscenely expensive considering that it bumps your backup from hours to days/weeks.
  - erikpukinskis 10y ago
    I don't understand your argument. A Powerwall, if it can get you through the trough, means in an emergency you have the same amount of power you'd have in a non-emergency.
    - maxerickson 10y ago

Kenji 10y ago

Not only that, but it's not uncommon for panels to crack. Kids throwing stones or balls, weather-related, etc. Replacing the glass is often difficult or expensive. Alternatively, you can fix it but that will often reduce the clarity and thus the generated electricity.

toomuchtodo 10y ago
Panels are sturdy enough to withstand 4 inch hail and hurricane winds if properly mounted to a roof or concrete ground support.

sandworm101 10y ago

You have a good point re roof penetrations. There are too many cowboy solar installers casually drilling holes thinking a blob of silicon is enough to seal out the rain. Also, when you eventually want to replace the roof handling and reinstalling the panel probably doubles the labour costs.

jandrese 10y ago
My thought is that you would install the solar panels when you're replacing the roof. Put 30 year panels on a 30 year roof. 30 years later you get to do it all over again, but at least you're not removing and reinstalling the panels when you replace the roof.
- sandworm101 10y ago
  Even without solar, few last 30 years without major repairs where I am (pacific northwest). There are lots of things to consider. Some/most solar installs don't take debris into account, creating dams that can send water places it shouldn't be, like up and under shingles. Not an issue in the desert but in rain forest it is a big deal. And the number of penetrations ... I've seen people put dozens of screws through what used to be a good roof. They cannot all be perfect.
  - ashark 10y ago
    Around here (midwest) hail or wind usually knocks out composite roofing in 10-15 years—much less if you're unlucky. There's little point in springing for the "50 year" composites and similar. I guess the solar panels would protect the roof a bit, but I'd expect a bad hail storm to be bad news for those, too.
secabeen 10y ago
This was a reason I put solar in after installing a standing seam metal roof. The roof will last 50+ years, and the solar just clamps onto the seams. Only penetration is for the cables to the inverter.

tsjackson 10y ago

Inverter failure is real, but the industry standard has risen to 12 years for string inverters, and 20-25 for micros. Even for string inverters, most of the residential/small commercial market has moved to using optimizers for voltage regulation, which means the inverter itself is a lot lighter weight/cheaper. Backup batteries are still relatively rare, as they should be - they are fairly expensive as backup power. Most systems remain grid tied. Smaller systems don't require retail net metering for a solid payback, since almost all of the energy is used as it is produced. Roof repair is again, real, but not as likely as you might think. Asphalt shingles under an array are protected from wind, and even more importantly, heat. They degrade at half the rate of the rest of the roof. Assuming 12-15 years for roof replacement, you will hit the module warrantied life of ~25 years before you need to replace the roof underneath the array. Cleaning the panels really only comes into play when the pitch of the roof is relatively shallow (3 on 12 or shallower). Otherwise rain will clean them fairly well. A lot of people won't have any trouble walking such a shallow pitched roof, and will simply hose the panels off once in a while. Also, in general, the price of modules per watt is about half of what it was 5 years ago. Peripherals are a major component of the improved economics, but module prices themselves have mattered just as much.

ChuckMcM 10y ago

> On another note, calculating the payback of > residential solar panels is tricky because many > online calculators don't consider (stuff...) Sometimes they do, we installed Solar in 2003, we replaced a failed inverter in 2016. At the time we installed the system we got a new roof with asphalt shingles (50 year roof) which both helped the roof load (they were lighter than the previous wood shake) and was a time period longer than the payback period for our panels.