shouldn't we have more effective ways of harnessing solar energy now? because

dominatrixjane

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shouldn't we have more effective ways of harnessing solar energy now?

because

Approximately 12000 TerraWatts of energy reaches the Earth from the Sun.

That is 1200000000000000 joules per minute.

More energy reaches the Earth from the Sun in one day

than the whole world uses in one year.
 
We have very effective solar systems.

There are three problems in general that impact the adoption of solar.

1. Batteries. Solar is an intermittent source of energy. To be efficient, it has to be gathered during the day and then stored for night time use. Batteries are expensive and toxic and efficient solar energy systems (on a city wide scale) require vast battery farms. Those batteries are dependent on rare earth materials, which are scarce and expensive to mine.

2. Environmental Impact. On a city-wide scale, solar farms require a significant conversion of land to host the solar arrays. Though it's usual glossed over, those solar arrays tend to have a significant environmental impact. In your more dense urban areas it is a question of being able to get sufficient space, since it usually means converting existing space to solar usage - and in most of America, converting property from one use form to another is massively bureaucratic.

3. Cost per megawatt hour. This is the cruelest and simplest of the challenges right now. The current cost per megawatt hour is $63.20 for PV Solar v. $50.10 for Natural Gas Combined Cycle.

Now, solar capacity is continually increasing, which is steadily lowering cost per megawatt hour. But, natural gas CC is also increasing efficiencies, so it's a slow race to lowest cost. Eventually, solar will overtake it, I kind of think that is inevitable, but cost matters. That is why proponents of solar seek out government subsidies to reduce both capital expenditures and operating costs. The political question here in the US is how much of this should be taxpayer subsidized. The challenge is the north tier of the US solar is not efficient due to the length and depth of winter. Solar has made terrific gains across the southern tier, where it doesn't have to battle the depth of winter and doesn't need the significantly larger capacity.

GO SOLAR!
 
Numbers listed here are approximate and good for showing the scale of the issue.

The earth receives approx. 1kwh/m^2per square meter of the Earth's Surface.
Photovoltaics appear to have an average efficiency of 15-18% or so.
In 2016 25,000 TW were produced worldwide.
This breaks down to needing approx 70TW per day to be generated at a minimum. Add in 20% for peak demand needs and we are up to 85TW generation needed.

SO we need to cover an area large enough to generate 85TW, but since the earth Rotates we need to make sure we have that much area continually in Sunlight.

To make it easy, lets use a higher efficiency cell and say 20%.
So we get 200w from a square meter of solar cell. So to get the full 1KW we need 5m^2. There are a billion Kw in a single TW, so we need 5 billion square meters of solar cells to get a single TW of electricity. Multiply that by 85 and you get a need for 425 billion square meters of solar cells.

That is 164,000 square miles. Now to produce this energy for all day you have to ensure this much solar paneling is always in FULL sunlight. Which means building entirely around the world.
Add in that at any point in time 67-70 percent of the surface of the earth is under clouds and production will be lower you need a bigger array to compensate.
So overbuild by 30% to handle cloud cover and you are up to over 213,000 square miles. Create 4 arrays so there is always ample sunlight around the world and you get to 852,000 square miles or 2.2*10^12 m2. 22,000,000,000,000.. 22 trillion square meters of cells needed.
The cost of solar cells is around $75 USD per square meter. SO.. now (not counting land use cost, etc... the cost of the cells alone is 1,650 trillion dollars.

The entire world economy is only worth 80 trillion dollars. So if bit of money on the planet was spent on NOTHING but solar production it would still take over 20 years to pay for it.

Of course this also ignores the fact that we simply do not have the necessary quantities of rare earth metals needed to fabricate that much photovoltaics. It simply does not exist in the quantities needed on earth.
 
shouldn't we have more effective ways of harnessing solar energy now?

because

Approximately 12000 TerraWatts of energy reaches the Earth from the Sun.

That is 1200000000000000 joules per minute.

More energy reaches the Earth from the Sun in one day

than the whole world uses in one year.

Yeah sure part of the problem is that a lot of the Earth is water. Only a few countries have tried to build offshore solar plants.

This is something more countries need to be able to do. Divesting from coal and oil would free up more than enough capital for this.
 
Yes. A definite part is that pesky 70% coverage by water. Add in that salt water is Very hard on electrical and electronics the need to harden any offshore site compounds the expense beyond the already considerable cost of building over open tide-driven water. It is not economically feasible for anything but the richest countries. Typically those who have access to Inexpensive energy in the form of fossil fuels.
I think we would be better off using Next-Gen failsafe Fission until we can get Fusion power to a practical level.
The land-use cost, and environmental cost of photovoltaics is quite high and that is apart from the low efficiencies and simple financial cost.
Sure we get a Lot of Energy from the sun but so far there are very few efficient methods to convert it to easily usable electricity
 
There are far better energy solutions than solar or wind. Granted, solar and wind power on a household level is an outstanding idea. But on any scale much larger than that they both take up too much space and are not completely reliable. A weeks worth of heavy overcast, or lack of wind and you're hurting.

But some of the best alternatives no one, especially the Gov't, wants to talk about.

Take Thorium as an example. A molten salt thorium reactor powerful enough to power Manhattan can be built in the space of your average Dollar General store, is far more efficient then a fission reactor, only radiation of any concern is Gamma and that is harmless to humans except in extreme amounts. Because it self contained and needs no cooling towers it can ALL be built underground. And no danger of a meltdown. To top it off, thorium is a mineral that is unearthed in the mining most metals and thrown away.

But the Gov doesn't want to discuss ANY type of reactor unless there is a weaponizable by-product. Something thorium doesn't have. So the Gov does its best to keep a lid on it.
 
Researchers find solar photovoltaics benefits outweigh costs

http://news.mit.edu/2020/researchers-find-solar-photovoltaics-benefits-outweigh-costs-0623


Global solar capacity addition to more than double over the next decade

https://www.thenational.ae/business...re-than-double-over-the-next-decade-1.1038479


Two-sided solar panels that track the sun produce a third more energy


https://www.newscientist.com/articl...at-track-the-sun-produce-a-third-more-energy/





Wells Fargo will buy 150 megawatts of solar power from Shell Energy

https://flipboard.com/article/https...hell-wells-fargo-solar-deal/?itid=sf_business


Indonesia Recovering Includes Planning $1 Billion Solar Energy Plan

https://www.greenqueen.com.hk/indon...ludes-planning-us1-billion-solar-energy-plan/


Van Aubel has been developing the solar panels for several years. they are created using light-absorbing organic dyes that cover tiny particles

https://www.dezeen.com/2020/06/22/c...n-van-aubel-will-dutch-biotope-expo-pavilion/
 
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