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."

Comments

Solar Cell Technology

[Laebshade]

Solar cell technology seems to be getting more and more advanced. When will the time come when we are able to use it to effectively power a complete house?

Re:Solar Cell Technology

[busterRey]

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.

Re:Solar Cell Technology

[llefler]

If you want to be completely solar, you have to attack the problem on several fronts. You need to find any way that you can to reduce power consumption. Then there are storage and backup power problems to deal with.

Since you didn't post capacity, it's hard to say what the $17k covers. I don't know if the programs are currently active, but in the past California had a tax rebate program that could offset about 1/2 of the cost of installation. I would be surprised if they missed that in the quote, but you might want to check. It would drastically cut payback time. Also remember that part of your payback comes in non-monetary benefits.

The type of system you were looking at is a good one, but probably needs a few adjustments. Being connected to the grid has a lot of advantages. The grid serves as your batteries. If your usage spikes (air conditioning?), the grid will make up the difference. And the grid supplies your power at night and when you can't produce.

When the grid goes down, you don't necessarily have to shut down too. When the grid goes down, you DO have to disconnect your PV units from the grid, regardless of whether they are producing or not. Neither you nor PG&E wants you powering their lines and electrocuting their linemen.

And if you look at it that way, compare the cost of lost revenue from over production to the cost of batteries. If losing the money bothers you that much, slightly undersize your system so you don't produce an excess amount. PG&E will happily cover the difference.

(cant come up with an appropriate topic)

[zaunuz]

Solar panels could really be the next generation power-source, if it can be developed a cheap and efective way of using solar energy. Have you seen that short-film on Discovery Channel about the guy who built a car that runs on solar power alone? You can walk faster than it, but hey, you could walk faster than the first steam-locomotives as well. But i'd still say that hydro-plants are the way to go, if the terrain allows it.

Solar power is nice

[dark404]

...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.

Re:Solar power is nice

[hawkbug]

I suggest you visit:

www.homepower.com

Solar power is very real, and many people already use it. Is it expensive? Yeah, for example a solar system to generate enough power for the average home would cost anywhere from $20k to $30k. Some states have to reimburse you for half your cost though - so immediately, you're down to $10k or $15k. Then, imagine that costing you about what a car payment would be for 5 years. Now imagine having that car payment *instead* of a utility bill. Now even better, imagine being paid off in 5 years - and then the panels and setup usually last 30 years. So, that equals 25 years of FREE energy. Most of these homes are still plugged into the grid so that at night they can either use the grid or batteries, while pumping excess onto the grid during the day to the power company has to buy that from you to power other homes in your area. Solar is great, and with rising natural gas costs, it's going to spread like a wildfire from global warming...

Solar power is going to be big

[ites]

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.

Re:Solar power is nice/false notions

[adzoox]

You have false notions about the feasability of solar. You would be speaking of cheap solar whereas (as it is now) there ISsolar technology that:

A) Doesn't have to cover the entire structure - but really is mute point - if you want solar - why not maximize its production - installation and deployment is 1/4 the cost - once it's being installed, install as much as possible - your goal is to "overproduce" if possible - did you know that your local energy untility has to BUY BACK power that you could place onto the grid if you overproduced?

B) The GM solar race car is a marvel of engineering, is as fast as most street legal cars and it looks cool too!

C) Cloud cover and night are of no consequence. Cloud cover only reduces production - besides power IS STORED in batteries anyway - it doesn't go straight from the sun to your light bulb or TV.

Solar constant

[garglblaster]

OK friends, before we get into some highly speculative terrain here, let's get some facts straight:
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..