pv energy payback time / publication of "Compared assessment ofselected environmental indicators of

[Mel]

Just published, the IEA PVPS Task 10 assesment on (roughly speaking)
urban grid connected pv energy payback times.


Downloadable here:
http://www.hespul.org/Vous-cherchez-des-statsitiques-des.html

and here:
http://www.iea-pvps-task10.org/


Regards,

 

[William P.N. Smith]

http://www.hespul.org/Vous-cherchez-des-statsitiques-des.html

/*
each 10 m2 of solar electricity panels installed can avoid up to 40
tons of CO2 emissions.
*/

Nice metric, thanks for the pointer!

 

[[email protected]]

/*
each 10 m2 of solar electricity panels installed can avoid up to 40
tons of CO2 emissions.
*/

Nice metric, thanks for the pointer!

I like the part that says the energy put into the manufacture of the panels
is returned in less than 2 years of operation.

That is an occasional point from some posters, that the energy used to
build the panels is never recouped. I've always thought that was
ludicrous. Energy is money. I have to pay more for the panels than they
cost to produce, so they must produce more energy than they required.
Whether that is valuable to me compared to the grid is a different story.

 

[Anthony Matonak]

I like the part that says the energy put into the manufacture of the panels
is returned in less than 2 years of operation.

That is an occasional point from some posters, that the energy used to
build the panels is never recouped. I've always thought that was
ludicrous. Energy is money. I have to pay more for the panels than they
cost to produce, so they must produce more energy than they required.

Energy is money? Where did you get that idea?
Have you ever tried to buy a burger with a kWh
or BTU?

Anthony

 

[John Beardmore]

/*
each 10 m2 of solar electricity panels installed can avoid up to 40
tons of CO2 emissions.

Over what time scale ?


Cheers, J/.

 

[William P.N. Smith]

Over what time scale ?

I didn't read the entire file in great detail, but AFAICT it's over
the lifespan of the solar array.

 

[[email protected]]

Energy is money? Where did you get that idea?
Have you ever tried to buy a burger with a kWh
or BTU?

No, but the same dollars that could buy some BTU could buy a burger.
If the solar manufacturer wants to be able to buy his own burgers, he is
going to have to charge me more dollars than what the kWH cost him.

 

[daestrom]

No, but the same dollars that could buy some BTU could buy a burger.
If the solar manufacturer wants to be able to buy his own burgers, he is
going to have to charge me more dollars than what the kWH cost him.

Trouble with this 'theory' (I think D Lancaster is behind it), is that not
all BTU are the same. Energy, in all its different forms is not fungible
like currency. That is where this whole 'energy is money' idea breaks down.

For example, would you give me 100 kwh of 600 psi steam in exchange for 100
kwh of luke-warm water?

How about I give you 1 MBTU of low-grade heat and you give me 1 MBTU of
electricity?

Don likes to 'refine' his statements and start talking about 'exergy is
money' in an attempt to correct for this shortcoming in the theory. But
even that is not completely fungible.

daestrom

 

[Anthony Matonak]

No, but the same dollars that could buy some BTU could buy a burger.
If the solar manufacturer wants to be able to buy his own burgers, he is
going to have to charge me more dollars than what the kWH cost him.

This only means that the energy costs (of the manufacturer)
are part of the sale price to a consumer. This applies to
anything, solar PV, bricks, cars, burgers.

How much power is a brick going to generate for you?

Anthony

 

[[email protected]]

Trouble with this 'theory' (I think D Lancaster is behind it), is that not
all BTU are the same. Energy, in all its different forms is not fungible
like currency. That is where this whole 'energy is money' idea breaks down.

Darn. I thought it was my idea.

For example, would you give me 100 kwh of 600 psi steam in exchange for 100
kwh of luke-warm water?

I'm not sure. I might have steam that I have expended some amount of
dollars to produce, and a lot of infrastructure to hold, and the lukewarm
water that you expended 100kwh to produce might be of lesser value, but,
depending on your definition of lukewarm, might be of inordinate value to
me at that moment.

The problem with bartering is determing the equivalent value.

Translating both halves of the barter to the coin of the realm gives a
common exchange element. I don't know what D. Lancaster's claim is, so I
wouldn't know if I agree with his definition or not.

 

[[email protected]]

This only means that the energy costs (of the manufacturer)
are part of the sale price to a consumer. This applies to
anything, solar PV, bricks, cars, burgers.

How much power is a brick going to generate for you?

I don't believe I'll be buying bricks as a part of an energy generation
scheme, although they might offer some side benefit in energy conservation.
They presumably aren't offered to market as energy generator or transport
devices.

I hear that they are also very effective as a wolf deterrent.