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Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

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Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#121

Post by DaniFong »

rasmuswissmann wrote: post #114
DaniFong wrote: post #99

Earlier quoted context omitted.

Sorry! This is a very subtle process. If you analyze it superficially, it makes sense, dig deeper and it's confusing, and then dig still deeper and it makes sense again. When you cool the air by mixing it with water spray, a good portion of the energy is now spent producing low temperature water vapour. So... how do you recover that energy? You'd need to condense the water vapour to get at the latent heat. You're rig…

From a technological point of view, is there any reason this is only possible now? Or would it have been possible decades ago, if only there had been enough interest in it or someone had had the idea earlier? This seems like a really smart feat of thermodynamical engineering, but it does not reference explicitly any technology that would not have been available 30 years ago. I could imagine that being hidden in the s…

In my judgement this could have been done in the 1800's.

Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#122

Post by DaniFong »

ck2 wrote: post #109

Why not use excess energy to lift millions of tons of worthless rock off the ground and then when power source fails, use the winding down via gravity to turn generators? Gravity is never going away and never going to run out.

There's a company called Energy Cache attempting that. Major design and construction challenge to achieve low cost. Maybe possible.

Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#123

Post by DaniFong »

jpdoctor wrote: post #117
akiselev wrote: post #107

Earlier quoted context omitted.

If you are a consumer hardware company, yes. If you're on the edges of what we as humans know to be possible, it can take far beyond Series D to get there. If you look at the early telecoms, they were essentially series Z with the government before becoming accessible. If you're talking about anything that has impact on utility scale power or anything else on a massive scale, series D is just the beginning. LightSail…

> If you are a consumer hardware company, yes. No I was referring to enterprise, and when it comes down to it, pretty much all VC funded operations. The nuts and bolts of the way VC funds are structured make it necessary to pretty much have the company investment resolved in about 8 years. (Typical funds are LLCs limited to 10 year frames.) Each round should last 1.5-2 yrs. If you are at D with no product, then your…

Right. Overfitting. Our first investment was 3 years ago.

Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#124

Post by boomzilla »

DaniFong wrote: post #123
jpdoctor wrote: post #117

Earlier quoted context omitted.

> If you are a consumer hardware company, yes. No I was referring to enterprise, and when it comes down to it, pretty much all VC funded operations. The nuts and bolts of the way VC funds are structured make it necessary to pretty much have the company investment resolved in about 8 years. (Typical funds are LLCs limited to 10 year frames.) Each round should last 1.5-2 yrs. If you are at D with no product, then your…

Right. Overfitting. Our first investment was 3 years ago.

Was there a big change in development direction, and a lot more capital is needed?

Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#125

Post by robomartin »

DaniFong wrote: post #100
robomartin wrote: post #95

Earlier quoted context omitted.

> Your calculations appear be within an order of magnitude of correct Being within an order of magnitude is absolutely fantastic for a quick set of calcs with unverified data pulled out of various 'net sites! So, about 6,000psi for 1m^3 ? I was just looking at this: http://www.nuvair.com/storage-storagetank.shtml Their NUVT6000 tanks will do it. Specs: Outside diameter: 9.4in Height: 52in Weight (empty): 195lbs. Air…

We get a higher energy density per m^3 of air at higher pressures. We were aiming at 4500 psi eventually. We aim for it not to be noisy -- any noise from high pressure air rushing out represents wasted energy. Sonic booms from exhaust have this problem in automobile engines, we avoid it. Lithium ion is indeed much more dense :-) Consider that every car has a gasoline tank, many houses have fuel oil, and we undergird…

> Consider that every car has a gasoline tank, many houses have fuel oil

Just guessing that this could be a gating issue once you have something to deploy. People can be irrational, even when faced with facts. I know people that will not go into the water at the beach for fear of being attacked by a shark. Yet, the same people don't think twice about getting into their cars in the morning and driving on Los Angeles freeways.

Here industrial design might be the key. If the unit looks, almost literally, like the typical freezer or refrigerator lots of people have in their garage it might mitigate irrational first impressions.

Good luck! I'll keep an eye on developments.

Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#126

Post by rasmuswissmann »

DaniFong wrote: post #121
rasmuswissmann wrote: post #114

Earlier quoted context omitted.

From a technological point of view, is there any reason this is only possible now? Or would it have been possible decades ago, if only there had been enough interest in it or someone had had the idea earlier? This seems like a really smart feat of thermodynamical engineering, but it does not reference explicitly any technology that would not have been available 30 years ago. I could imagine that being hidden in the s…

In my judgement this could have been done in the 1800's.

:)

Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#127

Post by aswanson »

aswanson wrote: post #93
DaniFong wrote: post #75

Earlier quoted context omitted.

Back at you tptacek!

Doubling down on that sentiment, Dani. Proud to see you making it happen, on something so major. I remember seeing an article in Forbes or Fortune last summer featuring you and a few other up and comers and yelling, "I know her!" in the bookstore. You're the truth, glad to see things happening for your vision.

Here we go:

http://www.forbes.com/special-report/2011/30-under30-12/30-u...

Re: Peter Thiel, Bill Gates, Khosla fund LightSail Energy in $37M Deal

#130

Post by DaniFong »

boomzilla wrote: post #124
DaniFong wrote: post #123

Earlier quoted context omitted.

Right. Overfitting. Our first investment was 3 years ago.

Was there a big change in development direction, and a lot more capital is needed?

No huge change. We decided to aim at a higher quality, product with more vertical integration/custom engineering which is somewhat more expensive from a development cost perspective but less from a unit cost perspective. When you can raise money from amazing investors like this, take a little extra. We were oversubscribed.
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