Solar? I hardly knew her!


I’m sorry about the title. Kinda.

I’m really worried about our planet.
I’m also onboard with the “The Singularity is near” philosophy.
As a result I try to keep tabs on break throughs and emerging trends that may help us … save the world.

Saving the world is tricky business. It’s not even an easy task to define the problem.
The problems are many.
The problems are complex.
The problems compound each other.
The sum usually ends at “We’re fucked.”

But this is not a “We’re fucked” post. This is an optimistic post.
I write it with full knowledge that no one piece of the puzzle, no one technology based solution, will do the job.
But hey, this is a blog post not a text book – so forgive me zooming in a bit.

Solar Power can, and I’m sure will, play a pivotal role as part of the solution.
The number of “breakthroughs” I see every week in my RSS reader is amazing. I couldn’t possibly list them all.
If we could somehow take the blinders off… get past all the patent, grant, and credit CYA nonsense there’s some really great stuff that may work well together.

Consider a few things… all awesome on their own… but potentially world changing together.
(* I concede that I’m a layperson – perhaps some of these things are mutually exclusive for some engineering/physics reason beyond my knowledge. I welcome any people in the know to weigh in. )

Solar Power Efficiency

There seems to be new ways to make solar panels more efficient, heat resistant, or thinner every week.

For example – a team at Princeton University has discovered that making solar panels LESS smooth can make them MORE efficient. Specifically here they were mimicking the veins and groves of leaves. Their prototype cells were 47% more efficient than similar cells that were smooth.

Granted, they were doing this test with plastic solar cells, which aren’t terribly efficient compared to silicon cells.
Hang on though… what if similar gains COULD be achieved on silicon?
What if a few grooves of silicon (or that magic graphene stuff) could help increase other types of cells, just by mimicking nature?
Shouldn’t someone be trying that?

Similar concepts are being explored at Stanford using teeny tiny mirrors.
That’s awesome, but what if it were more simple?

EVEN IF if it didn’t work out – seeing this type of jump in plastic based cells is super important.
Plastic cells are cheap, strong, and flexible. And this bump in efficiency may actually help make this robust type of cell worth while.

Interestingly the grooves efficiency varies by the wavelength of light. It was most pronounced in the red end of the spectrum.
Wouldn’t it be cool if you could route wavelengths of light to sections of the cell MOST efficient for it’s capture/conversion?
That would be incredibly helpful for ALL types of solar cells.

Well as it turns out The University of Utah has done that.

Keep Em Separated:
The fine folks at the University of Utah have created a thin glass film that breaks light into distinct wavelength (like a prism) which can be used to setup solar cells optimally.
They say it COULD lead to solar cells that are 50% more efficient.
(and that’s not considering any gains made by adding leaf like grooves)

Of course it’s worth noting here that Solar is already pretty darn efficient by most practical measures.

I want a new Duck:
Recently a guy named Dave Olsen gave the geo-thermal energy industry a wake up call.
They had been trying to position geo-thermal as a “baseload” power source but as it turns out… baseload power is actually problematic these days because there’s often too MUCH solar energy during the day. Using more “stable” power sources during those times means “curtailing thousands of megawatts of wind and solar”.

California faces severe midday energy over-generation, as evidenced by the famous “duck curve” chart below. In 2013 alone, California was forced to curtail more than 19 GWh of pre-purchased renewable energy in order to run its inflexible baseload sources, and this number will likely rise in the coming years. Adding more of these resources will only make this situation worse, said Olsen.

This “duck curve” shows the increased overgeneration risk and peak ramping needs (potentially 13 GW within three hours) that occur as more solar is added to the grid. Credit: CAISO

All very interesting and starts to bring up the question of energy storage.
Storage has always been one of the big problems with solar and wind. They are only only producing energy when the sun is shining or the wind is blowing. If these renewable resources are to become more mainstream we need to find a way to store up what is generated so that it can be used at a steady rate 24 hours a day.

This too is being addressed by lots of smart people.

Solar Power Storage

Power to spare:
Recently I saw a bold headline:
Company Claims It Has Solved Solar Energy Storage Problem

It’s really cool.
In a nut shell – mirrors (not solar cells) use the sun to heat a liquid (not water it boils too quick).
That super hotness makes steam that drives a turbine.
This company says they’ve found a material (they’re being pretty careful about giving away too much info) that allows them to store all that super hotness so they can drive those turbines around the clock.

Even more cool…
There are tiny grass roots entrepreneurs doing very similar things.
Terrajoule has a similar setup but uses a different storage method. (I think they use the steam to generate & store pressure which can be used to drive the engine after the sun goes down.)

Here’s a write up:
Terrajoule Unstealths Distributed Power via Solar And Energy-Storage

And if you’re interested here’s a rough video they made:


I mean… why aren’t we covering the desert with these things?!

But wait, there’s more!

Batteries Not Included:
Just today I saw this article about a solar cell that IS IT’S OWN BATTERY.

Some dangerously smart people at Ohio State University created a solar cell that stores the energy it creates… it is it’s own battery.

This is important because transferring energy from a solar cell to a battery is where a lot of loss happens. Not here.
The result is a cheap, highly efficient solar cell that needs no bulky battery.

And then there’s this thing…

Nothing’s Perfect, but this is close:
I don’t even know what to make of this yet within the context of the above… but it’s really exciting none the less.
According to the write up:

MIT researchers say they have developed a material that comes very close to the “ideal” for converting solar energy to heat (for conversion to electricity).

It should absorb virtually all wavelengths of light that reach Earth’s surface from the sun

It’s a little different in that it captures the sun’s energy as heat.
That heat makes things glow hot.
And the light from the glowing can be converted to energy.

Of particular note is that it’s being done with existing manufacturing techniques at a reasonable price.
The MIT team is using a very expensive metal because it stands up really well to heat, but in theory any metal with the right heat tolerance would work. With meta materials advancing as fast as they are I imagine there will be more options soon enough.

One more thing:

Having said all that – what if we used the sun, not to create energy, but to avoid needing it in the first place?
The LightCatcher from EcoNation may do just that.

It collects and widely disperses the light of the sun for indoor lighting. Drastically reducing the need for artificial light. It also blocks heat lowering the need for cooling. EcoNation says it can lower a company’s lighting energy costs by 70% (for big buildings)

Just a great idea.

Hey EcoNation – I hope you’re pitching this to Elon Musk for his new Giga Factory!

So yeah maybe there’s cause for optimism after all.