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Comment by bruce511 | Hacker News Reader

As a home owner with residential solar, I don't care about weight.

On the other hand any supplication involving transport does.

Both are very large markets, so weight would be a good point, especially if it was materially different.

So while you are correct, not all applications are weight sensitive, its an important factor. Or, to put it another way, if you discovered the new battery was half the weight of li-ion, how would that affect your opinion?

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Surprisingly when things become heavy enough the ground by itself isn't enough anymore and you start needing supports for heavy things

Interesting thought. If these are super cheap, at some point the foundations or the land they are on becomes a significant cost issue. Say for example if a 12 m long and 2.3 m wide standard 40 ft container weighs 16,000 kg (16 t), how many can you pile on an old parking lot?

I would assume the cost of the batteries (and then after that things like inverters) is still so high everything else is in the noise.

Randomly grabbed some soil strength (it varies alot), but a reasonable number seems 3000 pounds per square foot.

That puts your number at. (3k4010) / (16k*2.2) (estimating width of the 40 foot at 10 feet),

Uhh.. 34 containers. I think that's enough.

In reality you would be able to drive helicoil foundations or any number of things to change the dynamic. I agree the foundations would be secondary to the rest of the system cost in general though

Weight is a big deal for ebikes, especially eMTBs. I wouldn't mind a lighter phone/laptop either.

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