Good comment. My answer ...
According to , a publication with a growing reputation, the energy payback for a rooftop PV panel that works for 30 years is from 1 to 4 years. Thus for rooftop solar PV, EROEI is from 30/4=7.5 to 30/1=30.
(By the way, the 7.5 figure for EROEI is similar to the 7-8 range you cited later in your comment.)
Assume a PV panel lasts 30 years (some last much longer). Then, even if we take the pessimistic 7.5 EROEI as definitive -- and ignore the more optimistic figure of 30 -- we would spend the first four years of operation recovering our energy investment, get 22 years of essentially free energy, and still have four years left over to collect the energy needed to make replacement panels. This is obviously sustainable.
And as I noted previously, there is a lot of solar energy available -- thousands of times more energy than the world is using right now -- thousands of times more than coal, oil, hydro, nuclear, and so on combined. This is why I refuted @9dashline's doom and gloom on EROEI (Energy Return on Energy Invested).
So the plan is clear: use some of the energy we have now to make and install the solar panels. Then, in 30 years or so, use the energy collected by the panels to make replacement panels. We can keep this going indefinitely, as long as the sun shines (billions of years).
Okay, thanks for replying. Now I invite @9dashlline to justify his doom and gloom on EROEI.
Yes, that is true: we need to spend some energy to gather solar energy. But the payback is more than worth it, so much that we can get our energy investment back, have many years of essentially "free" energy, and then have a lot of energy left over to make more solar panels. This is obviously very sustainable.
According to , a publication with a growing reputation, the energy payback for a rooftop PV panel that works for 30 years is from 1 to 4 years. Thus for rooftop solar PV, EROEI is from 30/4=7.5 to 30/1=30.
(By the way, the 7.5 figure for EROEI is similar to the 7-8 range you cited later in your comment.)
Assume a PV panel lasts 30 years (some last much longer). Then, even if we take the pessimistic 7.5 EROEI as definitive -- and ignore the more optimistic figure of 30 -- we would spend the first four years of operation recovering our energy investment, get 22 years of essentially free energy, and still have four years left over to collect the energy needed to make replacement panels. This is obviously sustainable.
And as I noted previously, there is a lot of solar energy available -- thousands of times more energy than the world is using right now -- thousands of times more than coal, oil, hydro, nuclear, and so on combined. This is why I refuted @9dashline's doom and gloom on EROEI (Energy Return on Energy Invested).
So the plan is clear: use some of the energy we have now to make and install the solar panels. Then, in 30 years or so, use the energy collected by the panels to make replacement panels. We can keep this going indefinitely, as long as the sun shines (billions of years).
Okay, thanks for replying. Now I invite @9dashlline to justify his doom and gloom on EROEI.
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