New connection between stacked solar cells can handle energy of 70,000 suns

http://phys.org/news/2013-09-stacked-solar-cells-energy-suns.html

by pyre • 13 years ago

44 13 13 years ago

LAMike• 13 years ago

How far does battery tech have to go until it's feasible for lower-middle income families have a solar panel on their roof in LA/San Fransisco?

10%? 50%?

deletes• 13 years ago

http://en.wikipedia.org/wiki/Photovoltaic_system#Insolation_...

I'm taking the lowest value of 0.75 kWh per day. A quick look with google shows average yearly consumption per home is ~10000 kWh or 27.3kWh per day. So you would need about 36.5 m^2 for a home. That is about 6x6 meters and would fit nicely on a typical house, but probably not on a apartment building and much less on a skyscraper.

I assert that the problem is in the cost of the cells, cost and storage problem of batteries(no power at night and not relying on other sources) and unawareness of the general population.

I am not an expert on the this field and would gladly be corrected.

grannyg00se2• 13 years ago

It's not feasible for lower-middle income families until it is as cheap or cheaper than the alternatives.

But there are many factors complicating this kind of cost comparison. For one, pv solar pays off over years, while others are paid per as pennies per kWh used. Another complicating factor is the environmental impact of oil and coal. Do you include that? If you do, how do you quantify it?

This looks like a decent article http://greenecon.net/understanding-the-cost-of-solar-energy/...

In short, solar has a long way to go. Twenty or thirty times more expensive than the traditional sources of energy. It looks like a huge breakthrough and alternative method is needed rather than incremental improvements in current methods.

What this article is about is reducing cost by using a type of solar cell that can handle incredibly dense concentrations of sunlight. So you can use a cheap lens to take say 30 square feet of sunshine and focus it on one square foot of solar cell. Once square foot of solar cell is much cheaper than 5 square metres of solar cell. But the article doesn't go into detail about how much these high capacity solar cells would actually cost at mass consumption levels.

ams6110• 13 years ago

Concentrating sunlight like that also creates potentially dangerous high heat. As a kid I had a 24" fresnel lens that would almost instantly ignite anything I focused it on. Having an array of those on a residential rooftop would require some good safety engineering and insulation, which will add to the cost. It may still be a net win, but this might be something that's going to be more suitable for stand-alone, "solar farm" type installations.

6d0debc071• 13 years ago

This looks like a decent article

Their stats don't line up with the final cost to the consumer. Going by average LA energy costs

http://www.bls.gov/ro9/cpilosa_energy.htm

'Los Angeles area households paid an average of 20.3 cents per kilowatt hour (kWh) of electricity in July 2013, up from 19.3 cents per kWh in July 2012.'

Whereas, according to the linked article,

1 ton of coal costs $36 = $0.006 per KWH | 1 barrel of oil costs $70 = $0.05 per KWH | 1 cubic foot of gas $0.008 = $0.03 per KWH

Which may well be true, to the people with the powerplants, - but consumers can take advantage of the price of solar much more directly.

Assuming that we buy into their stats about the price of solar, (which I'm now a bit reluctant to do,) things look a bit happier; more like 1.7 times the price rather than twenty or thirty times.

Retric• 13 years ago

Those numbers are way off base. They assume 100% energy conversion when calculating costs which is a clear sign they have no clue what there talking about.

They also completely ignore the cost to build and maintain a coal power plant as well as transportation costs for coal. Consider the lack of west coast coal mines has a significant impact on the west coasts electricity costs.

Worse they use a reduculus 45,000 for 2kw system which is ~3 times the going rate. Solar is far from cost effective in Alaska but there are places in the US where solar + grid is cheaper than grid power.

PS: Off grid solar is not worth it, but neither is off grid coal so it's a pointless comparison.

ChuckMcM• 13 years ago

And be off-grid? Or just be energy-cost neutral? If you want the latter any number of folks can get 'zero cost' panels put on their roof by agreeing to buy their power from the panel installer instead of PG&E.

Off-grid is harder since there is a ton of maintenance that goes on with battery systems. That said, for a single family detached home, we're getting close to the point where there would be enough volume in the foundation / floor for charge storage in "super" caps. When we were installing the 5.2kV system on our house we looked at Maxell supercaps and it would have added another $122,000 to the install but you could have nominally fit them under the house (about 1800 sq ft of crawlspace). The reason I think such things would be better off being built into the foundation is that you really really don't want a rat to urinate on your system and cause a (brief) short. A lot of energy that can come out way to fast to be safe.

jotm• 13 years ago

It's already feasible if you've got the time and expertise (or will to learn) to build your own panels (from scratch, soldering solar cells and all) and do the installation yourself. Batteries are the cheapest part of a PV solar installation.

eksith• 13 years ago

I'm curious what this will mean for ROHS compliance. Gallium Arsenide isn't a terribly friendly substance and, depending on the concentrations, it could pose a safety issue during installation and/or recycling. https://en.wikipedia.org/wiki/Gallium_arsenide

aristidb• 13 years ago

If you concentrate the sun to "4000 suns", you also need _far_ fewer panels, so I think this fear might be overdone.

yason• 13 years ago

I wonder if there are constructions that also utilize the absorbed heat, i.e. energy that isn't caught by the solar cells. You could at least heat up the household water with that energy, or possibly use it to generate additional electricity on a parallel track or in combination with the solar cells.

bigd• 13 years ago

Not sure about this as is inorganic, but I am afraid all the Organic Photovoltaic business will be only another speculative bubble. It's been >10years now, millions have been spent, Konarka has failed, and investments are still raising when the scientific community only aims to an extra .1% to publish.

New connection between stacked solar cells can handle energy of 70,000 suns

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