Not talking here about alternatives to solar energy, just alternatives to the panel form-factor that is basically the standard solution for residential or commercial solar installations right now. In the past few months three very different alternatives to those panels have come to my attention.
Tesla Solar Roof
The first, and the only one that os already available as a product, is the Tesla solar roof. Rather than attaching panels on top of the roof tiles, this turns the tiles on the roof into solar cells (at least some of them – they have matching non-solar tiles that can be used for the remainder allowing a consistent roof with just the amount of power generation you need). Four different styles to choose from (eventually) mean these should be a viable replacement for any existing tile roof.
A great option for those who need to replace their roof anyway, but more expensive than solar panels. If you are one of those people who simply doesn’t like the look of conventional panels, then these might be a great alternative.
We’ve all seen the conventional solar panels, as well as the smaller solar cells on things like path lighting, road signs and even garbage cans. They are black/brown/bluish, and definitely not transparent. Fine if you are mounting them on a roof, but not, say, for replacing all the windows in a skyscraper, or the glass in the skylights of a factory or warehouse.
Scientists at Michigan State University have been developing their transparent organic solar concentrator. Unlike those conventional cells, these are truly transparent. They work by harvesting energy from light in the UV and IR parts of the spectrum, but allowing the visible portion of the spectrum to pass through.
That means these could be used to replace glass in many applications, whether it is the windows in those high rise buildings or the glass on the screen of a mobile phone. Currently, at just 5% efficient it doesn’t match conventional cells in efficiency (the ones I’ve been looking at for my home are around 18%-22% efficient), but unlike conventional solar that is limited to the roof space, it could be applied to every window in a building. And modern office buildings are essentially all windows. The efficiency will almost certainly improve too.
Flexible Solar Material
Finally, I had lunch with a friend last week and she let me know about a company working on a flexible, low cost solar material. The company, Energy Everywhere, seems to have something that could make installing solar much simpler. Quoting from their website:
Our game-changing solar cells are manufactured on roll-to-roll printing presses, similar to the traditional way printing is done. Starting with a thin plastic base film, specialized solar inks containing all the critical cell materials, are printed layer by layer.
That printing is also something they can set up locally, allowing the material to be printed near where it is needed. No mention of the relative efficiency of their solution compared to conventional panels, but it does claim to operate well in high temperature, high humidity and even low light conditions.