Slashdot Mirror
New Material for More Efficient Solar Cells
PunkerTFC writes "Space.com has an article on a new material that could create relatively cheap solar cells which are up to 50% efficient. This is much better than the 25% efficient silicon solar cells (most common) or the 36% efficient multi-junction solar cells (very expensive). The material was created by "forcing oxygen into a zinc-manganese-tellurium crystal" creating more band gaps, which allow the cell to create electrical energy with three seperate frequencies of light. This could lead to cheap, high-output solar cells in the future, but it will take at least 3 years to assess the feasibility of the new technology, according to the researchers."
It exists already.
This has been released very recently - it's based on PbSe crystals instead - at Los Alamos but also through University of California.
...but until it progresses to the point where we don't need a surface of cells an order of magnitude larger than the structure they will power to use them, they're still impracticle for primary energy needs.
I don't think we'll ever see solar cells as primary terestrial energy sources though. Cloud cover and night ruins their feasibility, but I'd wager money on them being used to augment other alternative energy sources in the future. Maybe power will go the way of Intel's new chips, multiple sources at lower power instead of one giant one at greater.
Oil reserves appear to be running out (looking at the recent problems Shell had with its overstated reserves, and seeing how some of the other large oil companies make even larger estimates than Shell's old ones). The future of energy production is going to be nuclear, wind, and solar. So it's very timely news.
Personally I think the collapse of the oil supply within the next 15-20 years will be the most traumatic event in recent human history.
Solar cells will help a lot in some ways but they won't be enough to stitch together a modern society built on the motor car and cheap fuel.
Sig for sale or rent. One previous user. Inquire within.
This was already covered by /. a few weeks ago, but this new space.com article does seems tohave more details.
The solar constant (see for example here is about 1.somethin kW per Square meter.
That simply means you need quite some substantial area irradiated by bright sunlight to obtain a given amount of energy.
I think this is a limiting factor for many interesting ideas out there..
perl -e 'printf("%x!\n",49153)'
Solar sales are up 30-40% every year, and have been growing at such a steady pace for a long time.
Naturally, this is a positive feedback loop. Lower prices mean it's affordable for more niches, which means more people buy, which in turn scales larger. At this point, it's pretty much unstoppable. It is useful in too many niches, especially where customers aren't connected to a power grid.
There are now many countries that have more cell-phones than landline phones. It's likely that in 10 years, some countries will have more customers getting electricity from solar than from a central grid. Naysayers will say it's not ready... but then again, 15 years ago cell phones weren't either. What matters is not the absolute numbers, but the growth rate of the industry and the evolution of the technology.
Of course, as the market matures, more people are doing R&D to find cheaper ways to build PV systems, which is only going to accelerate this momentum.
Information: "I want to be anthropomorphized"
I looked in to doing a PV installation on my house about two years ago. I live in California in the Santa Clara county and for most of the year there is plenty of sun. The cost of putting up enough panels to power the whole house was around 17K. At the time I figured the system would pay for itself in about 15 years. The problem for me was that the basic system most solar companies sell is still connected to the power grid and your payback is based on selling your excess back to the power company. During the day you supply the grid and you use the power grid as your night time battery. I wanted to be totally off the power grid because frankly I don't trust PG&E to pay me for my electricity (some folks in my area with these system have had that problem) and I don't want to be subject to their power problems. With system I was looking at if the PG&E power goes out your system goes dark too to protect itself. When I asked about at total off grid solution, the company I was talking with kind of choked a little and said they could set up a battery system for me and added about 10K to the price for the batteries and the extra gear needed to manage the batteries - and asked which part of the garage I was going to give up to house all of it. The other problem is that the batteries had a much shorter life span (5-10 years as I recall) and would have to be replaced much more often than the solar panels on the roof. I was told that the panels have a 25 year life span. Very quickly the economics didn't work out as I would end up paying more for solar power then I would buying from the power company. I still may do a solar installation at some point but I have decided to wait another year or so to see if the technology improves. I am not sure about the environmental impact of disposing of batteries. I guess they could be recycled to some extent but it would be problem. The bigger question is which is worse for the environment - dealing with the dead batteries my installation would generate or burning the fossil fuel to generate the power for my house. I just don't know. I would really like to see more efficient solar cells but we also need better storage systems. I was kind of hoping that fuel cell technology might help out there but don't know enough about it to say.
The moon may be smaller than the earth, but is it futher away - buster