Page 2 of 2 [ 20 posts ]  Go to page Previous  1, 2

QuantumChemist
Veteran
Veteran

User avatar

Joined: 18 Oct 2014
Gender: Male
Posts: 1,346
Location: Midwest

02 Apr 2021, 12:41 pm

A few things I wanted to point out about using solar in space:

1.) Solar cell technology is not 100% efficient. The band of energy that it can convert is extremely small when compared to the electromagnetic spectrum as a whole. There are ways to convert some of the other energy bands into the useable part, but it is not cheap to do.

2.) Solar cells wear out over time and must be replaced. Some of the materials to make them are quite toxic to handle. Higher end gammas can cook unprotected equipment, so it must be shielded from that portion.

3.) To send things into space requires huge amounts of energy. The process to get that energy creates pollution overall here on Earth.

Not to play devils advocate too hard, but there is a way to recycle oil from waste plastics. It can even be formed from carbon dioxide gas using very special catalysts based upon known research. The catch is that it is not easy nor cheap to do yet. Jet fuel is already being commercially made from wood pulp using genetically modified enzymes.

I think a combination of energy sources is needed, not just one over another. We are not at that level of technology to be able to make that goal of being green work without issues.



Fenn
Veteran
Veteran

User avatar

Joined: 1 Sep 2014
Gender: Male
Posts: 695
Location: Pennsylvania

02 Apr 2021, 3:33 pm

QuantumChemist
PV has the limits you described - but solar thermal does not - better efficiency and last longer - materials can be very simple:

https://en.wikipedia.org/wiki/List_of_s ... r_stations

https://en.wikipedia.org/wiki/Solar_the ... sh_designs

More development to be done - no engineering solution ever has no tradeoffs but space-based solar has a lot going for it.

Jet fuel made from wood pulp is taking energy from wood - which takes its energy from the sun.

Making chemical processes go up hill can be done - if you have the energy to do it. You can split water into hydrogen and oxygen too and hydrogen makes a great fuel - only water vapor as a by-product. But it helps to have the energy first.

On a brighter note here are ideas on how to do "carbon negative"
https://en.wikipedia.org/wiki/Climate_change_mitigation


_________________
ADHD-I(diagnosed) ASD-HF(undiagnosed - maybe)
RDOS scores - Aspie score 131/200 - neurotypical score 69/200 - very likely Aspie


PhosphorusDecree
Veteran
Veteran

User avatar

Joined: 3 May 2016
Age: 40
Gender: Male
Posts: 1,994
Location: Yorkshire, UK

04 Apr 2021, 11:59 am

Even though CO2 is produced during the manafacture of "green" power generators and batteries, it's still greener than fossil fuels, where CO2 is produced during the manufacture, during ongoing fossil fuel extraction, AND continually during operation. Lithium mining is the main problem, to my mind. The green energy revolution urgently needs to move away from lithium ion batteries.

There are some ideas for improving power storage in the works. Pumped hydro is one for national grids, though that takes up a lot of space. At least one company is working on portable kinetic-energy batteries based on flywheels- that's an old established technology, just needs to be made more user-friendly. A number of companies are working on batteries made from other alkali metals that are less rare or polluting to mine than lithium. Sodium ion batteries are an established technology- again, it's a matter of getting size down and efficiency up. Sodium is absolutely bloody everywhere. And recently-invented potassium ion batteries are potential even more energy dense than lithium ones.

Upgrading the power network is another thing that needs doing urgently. Over a large enough area, there's always going to be enough wind, solar or hydro energy available- the problem is getting it where it needs to be through antiquated power lines that stop at national or state borders. Twenty years ago there was talk of creating a super-grid connecting Europe and north Africa. This would benefit from sunlight in Algeria and wind in the North Sea as available, and all parts in between. That's one good argument for peace between nations, and once such a grid was in place, it would make it harder for nations that share it to go to war.

(Source: dozens of New Scientist and Scientific American articles over the years.... I don't still have them all, unfortunately. I'm too much of a hoarder as it is.)


_________________
Time flies like an arrow. Fruit flies like a banana.


RetroGamer87
Veteran
Veteran

User avatar

Joined: 30 Jul 2013
Age: 33
Gender: Male
Posts: 9,675
Location: Adelaide, Australia

04 May 2021, 5:06 am

Yes and no. I can't believe someone saying electric cars and solar panels are bad because it takes some energy to manufacture them without seeing a comparison of how much energy is used in their manufacture and how much energy they're likely to save.

I feel like the real threats from green technology comes from corporate greenwashing. I can't stand how they try to repackage environmentalism for their own purposes.


_________________
The days are long, but the years are short