Mydesign, thanks for that input, I wasn't aware of those hybrid generators. At least in concept, they sound like a good idea. In the Tokelau solution, "hvbrid" refers to a combo of solar panels plus coconut oil-based generators for backup and battery charging.
Ann, in our country there are some hybrid solar generators are available. Hybrid means a combination of both wind and solar. During day time solar energy is using for power generation and during night and dark time, wind mill will work to generate power. But in both cases, availability of sunlight and wind throughout year may be a concern.
Atwell, as of now for household purpose, the ROI from any solar based investment is 7-10 years (from my experience). I had done a comparative study and found that eventhough we are using low quality/cost panels and devices, then also it will take 5-8 years for enough ROI. But if the power tariffs are increasing, then we may able to get a good ROI below 5 year.
The hybrid solar/generator combination the author describes here is what Tokelau is using. That's the 3-island nation that just went 100% sustainable for its electrical need, which we wrote about here http://www.designnews.com/author.asp?section_id=1392&doc_id=254016 I think marrying flex circuit technology with solar cells is a great idea.
The problem I've had with using solar for my lawn mower is that the storage batteries don't last very long. In my application lead acid only lasts about three years. I just repacked with NiMh, hoping to get a little more life, but the cost of NiMh is about 3X of SLA, so it's a hefty pricetag. I realize that solar charging has nothing to do with the short life span of the batteries, but it does make me realize that all alternative energy sources need a better storage medium. Even if a medium drain application had to repack the cells every five years, the cost would be excessive.
Thanks for all the great comments. Solar has most definitely been used in the space industry for years. What Alta Devices is providing, is a similar (and in some cases higher) level of energy conversion efficiency, at price points and scale targeted at "mobile" terrestrial applications. The ability to embed power into every day materials is what sets us apart from the rest of the industry. We are certainly in an exciting phase in the industry.
Thin and flexible solar cells may be one of the solar energy waves of the future. We've reported on a few of these in DN. Here's one: http://www.designnews.com/author.asp?section_id=1392&doc_id=248975 and we'll be publishing a post on another one soon. Mydesign is correct, solar panels are used on spacecraft and satellites.
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