New Solar Panel Design Traps More Light

GoSun wrote in with an article about new solar panels that opens, "Sunlight has never really caught fire as a power source, mostly because generating electricity with solar cells is more expensive and less efficient than some conventional sources. But a new solar panel unveiled this month by the Georgia Tech Research Institute hopes to brighten the future of the energy source." The new panels are able to produce sixty times the current of traditional models.

Comments

Myth. Solar has a VERY good energy payback

[taharvey]

This is one of those grand myths that the public just can't shake. Photovoltaic's have a very good energy return on investment (EROI).

The energy payback peroid for various PV cell types are:
Crystal Silicon: 3.3 years
Multicrystal Si: 0.8 years
CIS: 0.4 years

To put that is perspective of EROI:
Photovoltaics (Si): 60:1 - 10:1 (based on above)
Wind: 60:1
Coal(US average): 9:1
Nuclear (light water): 4:1
Oil (mid-east): 10:1 - 30:1
Oil (US): 3:1 or less

And that is keeping in mind that the lifespan of PV is calculated at 30 years, an arbitrary number picked to equalize it with the life of a coal or nuclear power plant, however are panel warranties are 20-30 years alone. There is no reason to believe that the average lifespan of a PV panel won't be 40-60 years or more.

Re:Myth. Solar has a VERY good energy payback

[taharvey]

Three points:

1. My previous post was about Energy return on Investment. In other words, how much energy must be invested to extract another amount of energy. Not economics. Different issue.

2. The economics of solar however, are based on many issues. One such issue is it is being done on an inefficient small scale, by small time installers. Your Solar system would use around $45,000 in PV panels. Toss in another $7,500 for inverters, racks, etc. So you end up with around $30,000 in labor and profit - rather steep (find another installer). However, PV is currently competitive with some electric rates. On a equipment basis PV can produce power at around 8 cents/kilowatt hour at current prices - the rest is up to labor rates.

3. The solar market is a supply limited market, which is pushing prices up. Right now world-wide demand is outstripping supply by ~30%. It is seriously keeping prices inflated. Blame capitalism. Right now PV manufactures can charge whatever they want. But as the supply catches up, you see things change in the next 5 years.

4. Technology and manufacturing advances are bringing down costs as we speak - the question is when that will reflect in prices.

5. It is also a question of economic externailities. The US invests HUGE resources in securing the middle-east region because it has a critical resource: oil. Some estimates of the Iraq war alone, bring the US cost to $2 trillion. For the same amount we could have replaced 33% of our electric production with solar - proving free electricity in peripituitary.

not quite

[minuszero]

Actually, this approach is a different one to the multi-layered aproach you are probably referring to.

Said multi-layered approaches use multiple pn junctions with differing band-gaps, all on top of one another. This allows them to capture a broader spectrum of incoming light energies, thus increasing efficiency.

The approach referred to in this article is attacking a different problem - using a 3-D 'nano-tower' construction for the pn junctions in order to minimise the reflection of light, thus capturing more of it and therfore being more efficient.

While I'll agree that even this idea for such nano-cells has been around for a little while, it is still in very early stages of development, and has a long way to go. It is encouraging to see apparent evidence that the concept does work, however!