3 ms·

I believe most solar is sold by the watt, so you aren't gonna get a better deal by getting a more efficient panel, other than saving roof space.

hef19898 5y ago
Solar modules are priced per Watt peak, Wp, which is the nominal max power output. And the Wp prices are dropping every year.
otherme123 5y ago
Lets suposse you need 10kW to fulfill your needs. You can buy 10000/350=29 panels today at $200 each, or 25 400W panels tomorrow for $200 each. Saving $800 and roof space for the same output.
t8e56vd4ih 5y ago
that's exactly what efficiency means for solar panels
cfn 5y ago
Possibly the new 400W panels replaced the 360W for the same unit price. This happens every now and then.
dzhiurgis 5y ago
Labour cost is already on par with panels itself and probably going to be like 10x in 10 years.
- kragen 5y ago
  Maybe for rooftop solar. For utility-scale solar it won't work out like that. Imagine it's 02031 and you're running a utility-scale solar company and you want to put in a bid on Egypt's latest PPE RFQ for a 100-megawatt solar farm. The market price for PV modules is down to US$0.018 as you predict above, but the labor cost to install them is US$0.18, so your construction costs are US$198k + balance of plant. So, to break even, you need to make at least US$0.198/Wp from the PPE, and so do your competitors who are trying to underbid you. In this scenario, if you can find some way to automate 10% of the installation labor, you can save US$18,000 and underbid the competition by 5% (more realistically: 2.5%, because of balance-of-plant costs), guaranteeing you win the PPE. That's an environment that produces extremely strong incentives to invest in automation, and extremely favorable circumstances as well: on site at the solar plant, you control the entire environment except for, like, dust storms. And there's plenty of room for even very large machinery. Think about the scale of the draglines, excavators, and shovels used in open-pit coal mining. Some of these have hundred-meter-long booms; they can reach across an entire city block without walking. (They move by walking because they're too big for wheels or tracks.) Now consider that the available solar energy resource is three orders of magnitude larger than coal ever was, and instead of a mountain-sized coal seam you're mining a country-sized "seam" of sunlight.
  - dzhiurgis 5y ago
    5% more efficient panels also means 5% less panels to install, cutting the labour cost again.
    - kragen 5y ago
      Yup, but there's a limit of about a factor of five or six there, since the panels can't be more than 100% efficient.

hef19898 5y ago

Solar modules are priced per Watt peak, Wp, which is the nominal max power output. And the Wp prices are dropping every year.

otherme123 5y ago

Lets suposse you need 10kW to fulfill your needs. You can buy 10000/350=29 panels today at $200 each, or 25 400W panels tomorrow for $200 each. Saving $800 and roof space for the same output.

t8e56vd4ih 5y ago

that's exactly what efficiency means for solar panels

cfn 5y ago

Possibly the new 400W panels replaced the 360W for the same unit price. This happens every now and then.

dzhiurgis 5y ago

Labour cost is already on par with panels itself and probably going to be like 10x in 10 years.

kragen 5y ago
Maybe for rooftop solar. For utility-scale solar it won't work out like that. Imagine it's 02031 and you're running a utility-scale solar company and you want to put in a bid on Egypt's latest PPE RFQ for a 100-megawatt solar farm. The market price for PV modules is down to US$0.018 as you predict above, but the labor cost to install them is US$0.18, so your construction costs are US$198k + balance of plant. So, to break even, you need to make at least US$0.198/Wp from the PPE, and so do your competitors who are trying to underbid you. In this scenario, if you can find some way to automate 10% of the installation labor, you can save US$18,000 and underbid the competition by 5% (more realistically: 2.5%, because of balance-of-plant costs), guaranteeing you win the PPE. That's an environment that produces extremely strong incentives to invest in automation, and extremely favorable circumstances as well: on site at the solar plant, you control the entire environment except for, like, dust storms. And there's plenty of room for even very large machinery. Think about the scale of the draglines, excavators, and shovels used in open-pit coal mining. Some of these have hundred-meter-long booms; they can reach across an entire city block without walking. (They move by walking because they're too big for wheels or tracks.) Now consider that the available solar energy resource is three orders of magnitude larger than coal ever was, and instead of a mountain-sized coal seam you're mining a country-sized "seam" of sunlight.
- dzhiurgis 5y ago
  5% more efficient panels also means 5% less panels to install, cutting the labour cost again.
  - kragen 5y ago
    Yup, but there's a limit of about a factor of five or six there, since the panels can't be more than 100% efficient.