CO2 savings via a PV solar system

As of yesterday, my year to date total value, since going on line Aug/04, with my 7.5 kW system I have generated 58,783 kWh of Solar Power!

Iguess that means 999311 CO2 savings!!!

GO SOLAR!!!

PAT KK6PD

 

It all depends on the source of your power and efficiency of the plant.

If my calculations are correct you should multiply 0.698043165 by the number of kWh to get the total kg of carbon saved from coal power. That is an avg value as coal from different locations burned in different plants produce different amounts of power. This value comes pretty close to the SMA value my Solar system gives me. I am not sure what the conversion is for kW vs kWh. So I am not sure how they get 1.7.

 

0.698 kg = 1.54 lbs Not quite 1.7, but not far off. 1.54 seems to be the number Energy Star uses for their CFL program calculations. Below is an example from Aspen where two power companies come in at 1.265 and 1.795. Here in AZ we run about 1 lb/kWh due to large nuclear contribution, & some hydro.

http://aspenglobalwarming.com/pdf/01Elec&Notes.pdf

So, as you said it does vary quite a bit depending on sources. You'd really want to at least get your state average, if not a number from your actual power company.

Rob

 

Ok you math wizards, anyone know how much energy is needed to manufacture a 100 watt solar panel?(in other words, the energy to dig up the silicon, to refine it to polysilicon, process the panel, etc...)

 

oops did did not notice you were working in imperial measurements. So I guess the 1.7 is not too far off. Maybe they estimate the worse case scenario power plant. Also they are a German company so many that is the avg for power plants in Europe.

Again, not all manufacturers are created equal. Each has a different process and uses different material. I do recall reading a study that came to the conclusion that over the 25-yr life span of a panel, it does create more energy than it takes to make the panel. For some reason the figure of $4.5 to $5 a watt come to mind for the cost to make the panels. My house system costs $6.75 a watt including installation. This is without any rebates. I am not sure if the gov't provides any subsidies prior to the sale.

 

Amortized for over the live of the panel vs the life of a coal or gas fired plant,,,,way less. Silicon, while not cheap to refine is abundant. Panels have a life span warranted for ~20 have a life expectancy of 40+ years.

Icarus

PS I don't know the detailed answer to your question however.

 

It really depends on the the panel. The recent panels are using less and less silicon because of the supply constraints. So compared to older panels the EROI is probably considerably better. Also, mono vs polycrystalline vs amorphous/thin film way be important in the calculation.

 

I remember hearing once that the EROI is around 2 years. I can't verify that or remember the source (mighta been darrel). Again, could be considerably less now given panel mfg methods.

 

Wow. I went on line 11/04 with my 3.3 KW system. To date I'm at 16,300 kWh.

 

I don't have any specific numbers, but its low. This was a real concern back in the '50s-60s when the technology was very new and efficiencies were very low. My understanding is that currently the entire energy cost of raw materials, manufacturing, transport & installation is now covered in less than 1 year on an average system.

Rob